linux/net/rxrpc/input.c

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/* RxRPC packet reception
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/errqueue.h>
#include <linux/udp.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/icmp.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/gfp.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <net/ip.h>
#include <net/udp.h>
#include <net/net_namespace.h>
#include "ar-internal.h"
/*
* queue a packet for recvmsg to pass to userspace
* - the caller must hold a lock on call->lock
* - must not be called with interrupts disabled (sk_filter() disables BH's)
* - eats the packet whether successful or not
* - there must be just one reference to the packet, which the caller passes to
* this function
*/
int rxrpc_queue_rcv_skb(struct rxrpc_call *call, struct sk_buff *skb,
bool force, bool terminal)
{
struct rxrpc_skb_priv *sp;
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
struct rxrpc_sock *rx = call->socket;
struct sock *sk;
int ret;
_enter(",,%d,%d", force, terminal);
ASSERT(!irqs_disabled());
sp = rxrpc_skb(skb);
ASSERTCMP(sp->call, ==, call);
/* if we've already posted the terminal message for a call, then we
* don't post any more */
if (test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags)) {
_debug("already terminated");
ASSERTCMP(call->state, >=, RXRPC_CALL_COMPLETE);
rxrpc_free_skb(skb);
return 0;
}
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
sk = &rx->sk;
if (!force) {
/* cast skb->rcvbuf to unsigned... It's pointless, but
* reduces number of warnings when compiling with -W
* --ANK */
// ret = -ENOBUFS;
// if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
// (unsigned int) sk->sk_rcvbuf)
// goto out;
ret = sk_filter(sk, skb);
if (ret < 0)
goto out;
}
spin_lock_bh(&sk->sk_receive_queue.lock);
if (!test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags) &&
!test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
call->socket->sk.sk_state != RXRPC_CLOSE) {
skb->destructor = rxrpc_packet_destructor;
skb->dev = NULL;
skb->sk = sk;
atomic_add(skb->truesize, &sk->sk_rmem_alloc);
if (terminal) {
_debug("<<<< TERMINAL MESSAGE >>>>");
set_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags);
}
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
/* allow interception by a kernel service */
if (rx->interceptor) {
rx->interceptor(sk, call->user_call_ID, skb);
spin_unlock_bh(&sk->sk_receive_queue.lock);
} else {
_net("post skb %p", skb);
__skb_queue_tail(&sk->sk_receive_queue, skb);
spin_unlock_bh(&sk->sk_receive_queue.lock);
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_data_ready(sk);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
}
skb = NULL;
} else {
spin_unlock_bh(&sk->sk_receive_queue.lock);
}
ret = 0;
out:
rxrpc: Fix races between skb free, ACK generation and replying Inside the kafs filesystem it is possible to occasionally have a call processed and terminated before we've had a chance to check whether we need to clean up the rx queue for that call because afs_send_simple_reply() ends the call when it is done, but this is done in a workqueue item that might happen to run to completion before afs_deliver_to_call() completes. Further, it is possible for rxrpc_kernel_send_data() to be called to send a reply before the last request-phase data skb is released. The rxrpc skb destructor is where the ACK processing is done and the call state is advanced upon release of the last skb. ACK generation is also deferred to a work item because it's possible that the skb destructor is not called in a context where kernel_sendmsg() can be invoked. To this end, the following changes are made: (1) kernel_rxrpc_data_consumed() is added. This should be called whenever an skb is emptied so as to crank the ACK and call states. This does not release the skb, however. kernel_rxrpc_free_skb() must now be called to achieve that. These together replace rxrpc_kernel_data_delivered(). (2) kernel_rxrpc_data_consumed() is wrapped by afs_data_consumed(). This makes afs_deliver_to_call() easier to work as the skb can simply be discarded unconditionally here without trying to work out what the return value of the ->deliver() function means. The ->deliver() functions can, via afs_data_complete(), afs_transfer_reply() and afs_extract_data() mark that an skb has been consumed (thereby cranking the state) without the need to conditionally free the skb to make sure the state is correct on an incoming call for when the call processor tries to send the reply. (3) rxrpc_recvmsg() now has to call kernel_rxrpc_data_consumed() when it has finished with a packet and MSG_PEEK isn't set. (4) rxrpc_packet_destructor() no longer calls rxrpc_hard_ACK_data(). Because of this, we no longer need to clear the destructor and put the call before we free the skb in cases where we don't want the ACK/call state to be cranked. (5) The ->deliver() call-type callbacks are made to return -EAGAIN rather than 0 if they expect more data (afs_extract_data() returns -EAGAIN to the delivery function already), and the caller is now responsible for producing an abort if that was the last packet. (6) There are many bits of unmarshalling code where: ret = afs_extract_data(call, skb, last, ...); switch (ret) { case 0: break; case -EAGAIN: return 0; default: return ret; } is to be found. As -EAGAIN can now be passed back to the caller, we now just return if ret < 0: ret = afs_extract_data(call, skb, last, ...); if (ret < 0) return ret; (7) Checks for trailing data and empty final data packets has been consolidated as afs_data_complete(). So: if (skb->len > 0) return -EBADMSG; if (!last) return 0; becomes: ret = afs_data_complete(call, skb, last); if (ret < 0) return ret; (8) afs_transfer_reply() now checks the amount of data it has against the amount of data desired and the amount of data in the skb and returns an error to induce an abort if we don't get exactly what we want. Without these changes, the following oops can occasionally be observed, particularly if some printks are inserted into the delivery path: general protection fault: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 0 PID: 1305 Comm: kworker/u8:3 Tainted: G E 4.7.0-fsdevel+ #1303 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 Workqueue: kafsd afs_async_workfn [kafs] task: ffff88040be041c0 ti: ffff88040c070000 task.ti: ffff88040c070000 RIP: 0010:[<ffffffff8108fd3c>] [<ffffffff8108fd3c>] __lock_acquire+0xcf/0x15a1 RSP: 0018:ffff88040c073bc0 EFLAGS: 00010002 RAX: 6b6b6b6b6b6b6b6b RBX: 0000000000000000 RCX: ffff88040d29a710 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88040d29a710 RBP: ffff88040c073c70 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88040be041c0 R15: ffffffff814c928f FS: 0000000000000000(0000) GS:ffff88041fa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa4595f4750 CR3: 0000000001c14000 CR4: 00000000001406f0 Stack: 0000000000000006 000000000be04930 0000000000000000 ffff880400000000 ffff880400000000 ffffffff8108f847 ffff88040be041c0 ffffffff81050446 ffff8803fc08a920 ffff8803fc08a958 ffff88040be041c0 ffff88040c073c38 Call Trace: [<ffffffff8108f847>] ? mark_held_locks+0x5e/0x74 [<ffffffff81050446>] ? __local_bh_enable_ip+0x9b/0xa1 [<ffffffff8108f9ca>] ? trace_hardirqs_on_caller+0x16d/0x189 [<ffffffff810915f4>] lock_acquire+0x122/0x1b6 [<ffffffff810915f4>] ? lock_acquire+0x122/0x1b6 [<ffffffff814c928f>] ? skb_dequeue+0x18/0x61 [<ffffffff81609dbf>] _raw_spin_lock_irqsave+0x35/0x49 [<ffffffff814c928f>] ? skb_dequeue+0x18/0x61 [<ffffffff814c928f>] skb_dequeue+0x18/0x61 [<ffffffffa009aa92>] afs_deliver_to_call+0x344/0x39d [kafs] [<ffffffffa009ab37>] afs_process_async_call+0x4c/0xd5 [kafs] [<ffffffffa0099e9c>] afs_async_workfn+0xe/0x10 [kafs] [<ffffffff81063a3a>] process_one_work+0x29d/0x57c [<ffffffff81064ac2>] worker_thread+0x24a/0x385 [<ffffffff81064878>] ? rescuer_thread+0x2d0/0x2d0 [<ffffffff810696f5>] kthread+0xf3/0xfb [<ffffffff8160a6ff>] ret_from_fork+0x1f/0x40 [<ffffffff81069602>] ? kthread_create_on_node+0x1cf/0x1cf Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-03 13:11:40 +00:00
rxrpc_free_skb(skb);
_leave(" = %d", ret);
return ret;
}
/*
* process a DATA packet, posting the packet to the appropriate queue
* - eats the packet if successful
*/
static int rxrpc_fast_process_data(struct rxrpc_call *call,
struct sk_buff *skb, u32 seq)
{
struct rxrpc_skb_priv *sp;
bool terminal;
int ret, ackbit, ack;
rxrpc: Fix a use-after-push in data_ready handler Fix a use of a packet after it has been enqueued onto the packet processing queue in the data_ready handler. Once on a call's Rx queue, we mustn't touch it any more as it may be dequeued and freed by the call processor running on a work queue. Save the values we need before enqueuing. Without this, we can get an oops like the following: BUG: unable to handle kernel NULL pointer dereference at 000000000000009c IP: [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] PGD 0 Oops: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G E 4.7.0-fsdevel+ #1336 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 task: ffff88040d6863c0 task.stack: ffff88040d68c000 RIP: 0010:[<ffffffffa01854e8>] [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] RSP: 0018:ffff88041fb03a78 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff8803ff195b00 RCX: 0000000000000001 RDX: ffffffffa01854d1 RSI: 0000000000000008 RDI: ffff8803ff195b00 RBP: ffff88041fb03ab0 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88041fb038c8 R11: 0000000000000000 R12: ffff880406874800 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88041fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000009c CR3: 0000000001c14000 CR4: 00000000001406e0 Stack: ffff8803ff195ea0 ffff880408348800 ffff880406874800 ffff8803ff195b00 ffff880408348800 ffff8803ff195ed8 0000000000000000 ffff88041fb03af0 ffffffffa0186072 0000000000000000 ffff8804054da000 0000000000000000 Call Trace: <IRQ> [<ffffffffa0186072>] rxrpc_data_ready+0x89d/0xbae [af_rxrpc] [<ffffffff814c94d7>] __sock_queue_rcv_skb+0x24c/0x2b2 [<ffffffff8155c59a>] __udp_queue_rcv_skb+0x4b/0x1bd [<ffffffff8155e048>] udp_queue_rcv_skb+0x281/0x4db [<ffffffff8155ea8f>] __udp4_lib_rcv+0x7ed/0x963 [<ffffffff8155ef9a>] udp_rcv+0x15/0x17 [<ffffffff81531d86>] ip_local_deliver_finish+0x1c3/0x318 [<ffffffff81532544>] ip_local_deliver+0xbb/0xc4 [<ffffffff81531bc3>] ? inet_del_offload+0x40/0x40 [<ffffffff815322a9>] ip_rcv_finish+0x3ce/0x42c [<ffffffff81532851>] ip_rcv+0x304/0x33d [<ffffffff81531edb>] ? ip_local_deliver_finish+0x318/0x318 [<ffffffff814dff9d>] __netif_receive_skb_core+0x601/0x6e8 [<ffffffff814e072e>] __netif_receive_skb+0x13/0x54 [<ffffffff814e082a>] netif_receive_skb_internal+0xbb/0x17c [<ffffffff814e1838>] napi_gro_receive+0xf9/0x1bd [<ffffffff8144eb9f>] rtl8169_poll+0x32b/0x4a8 [<ffffffff814e1c7b>] net_rx_action+0xe8/0x357 [<ffffffff81051074>] __do_softirq+0x1aa/0x414 [<ffffffff810514ab>] irq_exit+0x3d/0xb0 [<ffffffff810184a2>] do_IRQ+0xe4/0xfc [<ffffffff81612053>] common_interrupt+0x93/0x93 <EOI> [<ffffffff814af837>] ? cpuidle_enter_state+0x1ad/0x2be [<ffffffff814af832>] ? cpuidle_enter_state+0x1a8/0x2be [<ffffffff814af96a>] cpuidle_enter+0x12/0x14 [<ffffffff8108956f>] call_cpuidle+0x39/0x3b [<ffffffff81089855>] cpu_startup_entry+0x230/0x35d [<ffffffff810312ea>] start_secondary+0xf4/0xf7 Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-09 10:30:43 +00:00
u32 serial;
u8 flags;
_enter("{%u,%u},,{%u}", call->rx_data_post, call->rx_first_oos, seq);
sp = rxrpc_skb(skb);
ASSERTCMP(sp->call, ==, NULL);
rxrpc: Fix a use-after-push in data_ready handler Fix a use of a packet after it has been enqueued onto the packet processing queue in the data_ready handler. Once on a call's Rx queue, we mustn't touch it any more as it may be dequeued and freed by the call processor running on a work queue. Save the values we need before enqueuing. Without this, we can get an oops like the following: BUG: unable to handle kernel NULL pointer dereference at 000000000000009c IP: [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] PGD 0 Oops: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G E 4.7.0-fsdevel+ #1336 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 task: ffff88040d6863c0 task.stack: ffff88040d68c000 RIP: 0010:[<ffffffffa01854e8>] [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] RSP: 0018:ffff88041fb03a78 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff8803ff195b00 RCX: 0000000000000001 RDX: ffffffffa01854d1 RSI: 0000000000000008 RDI: ffff8803ff195b00 RBP: ffff88041fb03ab0 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88041fb038c8 R11: 0000000000000000 R12: ffff880406874800 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88041fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000009c CR3: 0000000001c14000 CR4: 00000000001406e0 Stack: ffff8803ff195ea0 ffff880408348800 ffff880406874800 ffff8803ff195b00 ffff880408348800 ffff8803ff195ed8 0000000000000000 ffff88041fb03af0 ffffffffa0186072 0000000000000000 ffff8804054da000 0000000000000000 Call Trace: <IRQ> [<ffffffffa0186072>] rxrpc_data_ready+0x89d/0xbae [af_rxrpc] [<ffffffff814c94d7>] __sock_queue_rcv_skb+0x24c/0x2b2 [<ffffffff8155c59a>] __udp_queue_rcv_skb+0x4b/0x1bd [<ffffffff8155e048>] udp_queue_rcv_skb+0x281/0x4db [<ffffffff8155ea8f>] __udp4_lib_rcv+0x7ed/0x963 [<ffffffff8155ef9a>] udp_rcv+0x15/0x17 [<ffffffff81531d86>] ip_local_deliver_finish+0x1c3/0x318 [<ffffffff81532544>] ip_local_deliver+0xbb/0xc4 [<ffffffff81531bc3>] ? inet_del_offload+0x40/0x40 [<ffffffff815322a9>] ip_rcv_finish+0x3ce/0x42c [<ffffffff81532851>] ip_rcv+0x304/0x33d [<ffffffff81531edb>] ? ip_local_deliver_finish+0x318/0x318 [<ffffffff814dff9d>] __netif_receive_skb_core+0x601/0x6e8 [<ffffffff814e072e>] __netif_receive_skb+0x13/0x54 [<ffffffff814e082a>] netif_receive_skb_internal+0xbb/0x17c [<ffffffff814e1838>] napi_gro_receive+0xf9/0x1bd [<ffffffff8144eb9f>] rtl8169_poll+0x32b/0x4a8 [<ffffffff814e1c7b>] net_rx_action+0xe8/0x357 [<ffffffff81051074>] __do_softirq+0x1aa/0x414 [<ffffffff810514ab>] irq_exit+0x3d/0xb0 [<ffffffff810184a2>] do_IRQ+0xe4/0xfc [<ffffffff81612053>] common_interrupt+0x93/0x93 <EOI> [<ffffffff814af837>] ? cpuidle_enter_state+0x1ad/0x2be [<ffffffff814af832>] ? cpuidle_enter_state+0x1a8/0x2be [<ffffffff814af96a>] cpuidle_enter+0x12/0x14 [<ffffffff8108956f>] call_cpuidle+0x39/0x3b [<ffffffff81089855>] cpu_startup_entry+0x230/0x35d [<ffffffff810312ea>] start_secondary+0xf4/0xf7 Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-09 10:30:43 +00:00
flags = sp->hdr.flags;
serial = sp->hdr.serial;
spin_lock(&call->lock);
if (call->state > RXRPC_CALL_COMPLETE)
goto discard;
ASSERTCMP(call->rx_data_expect, >=, call->rx_data_post);
ASSERTCMP(call->rx_data_post, >=, call->rx_data_recv);
ASSERTCMP(call->rx_data_recv, >=, call->rx_data_eaten);
if (seq < call->rx_data_post) {
_debug("dup #%u [-%u]", seq, call->rx_data_post);
ack = RXRPC_ACK_DUPLICATE;
ret = -ENOBUFS;
goto discard_and_ack;
}
/* we may already have the packet in the out of sequence queue */
ackbit = seq - (call->rx_data_eaten + 1);
ASSERTCMP(ackbit, >=, 0);
if (__test_and_set_bit(ackbit, call->ackr_window)) {
_debug("dup oos #%u [%u,%u]",
seq, call->rx_data_eaten, call->rx_data_post);
ack = RXRPC_ACK_DUPLICATE;
goto discard_and_ack;
}
if (seq >= call->ackr_win_top) {
_debug("exceed #%u [%u]", seq, call->ackr_win_top);
__clear_bit(ackbit, call->ackr_window);
ack = RXRPC_ACK_EXCEEDS_WINDOW;
goto discard_and_ack;
}
if (seq == call->rx_data_expect) {
clear_bit(RXRPC_CALL_EXPECT_OOS, &call->flags);
call->rx_data_expect++;
} else if (seq > call->rx_data_expect) {
_debug("oos #%u [%u]", seq, call->rx_data_expect);
call->rx_data_expect = seq + 1;
if (test_and_set_bit(RXRPC_CALL_EXPECT_OOS, &call->flags)) {
ack = RXRPC_ACK_OUT_OF_SEQUENCE;
goto enqueue_and_ack;
}
goto enqueue_packet;
}
if (seq != call->rx_data_post) {
_debug("ahead #%u [%u]", seq, call->rx_data_post);
goto enqueue_packet;
}
if (test_bit(RXRPC_CALL_RCVD_LAST, &call->flags))
goto protocol_error;
/* if the packet need security things doing to it, then it goes down
* the slow path */
if (call->conn->security_ix)
goto enqueue_packet;
sp->call = call;
rxrpc_get_call(call);
rxrpc: Fix races between skb free, ACK generation and replying Inside the kafs filesystem it is possible to occasionally have a call processed and terminated before we've had a chance to check whether we need to clean up the rx queue for that call because afs_send_simple_reply() ends the call when it is done, but this is done in a workqueue item that might happen to run to completion before afs_deliver_to_call() completes. Further, it is possible for rxrpc_kernel_send_data() to be called to send a reply before the last request-phase data skb is released. The rxrpc skb destructor is where the ACK processing is done and the call state is advanced upon release of the last skb. ACK generation is also deferred to a work item because it's possible that the skb destructor is not called in a context where kernel_sendmsg() can be invoked. To this end, the following changes are made: (1) kernel_rxrpc_data_consumed() is added. This should be called whenever an skb is emptied so as to crank the ACK and call states. This does not release the skb, however. kernel_rxrpc_free_skb() must now be called to achieve that. These together replace rxrpc_kernel_data_delivered(). (2) kernel_rxrpc_data_consumed() is wrapped by afs_data_consumed(). This makes afs_deliver_to_call() easier to work as the skb can simply be discarded unconditionally here without trying to work out what the return value of the ->deliver() function means. The ->deliver() functions can, via afs_data_complete(), afs_transfer_reply() and afs_extract_data() mark that an skb has been consumed (thereby cranking the state) without the need to conditionally free the skb to make sure the state is correct on an incoming call for when the call processor tries to send the reply. (3) rxrpc_recvmsg() now has to call kernel_rxrpc_data_consumed() when it has finished with a packet and MSG_PEEK isn't set. (4) rxrpc_packet_destructor() no longer calls rxrpc_hard_ACK_data(). Because of this, we no longer need to clear the destructor and put the call before we free the skb in cases where we don't want the ACK/call state to be cranked. (5) The ->deliver() call-type callbacks are made to return -EAGAIN rather than 0 if they expect more data (afs_extract_data() returns -EAGAIN to the delivery function already), and the caller is now responsible for producing an abort if that was the last packet. (6) There are many bits of unmarshalling code where: ret = afs_extract_data(call, skb, last, ...); switch (ret) { case 0: break; case -EAGAIN: return 0; default: return ret; } is to be found. As -EAGAIN can now be passed back to the caller, we now just return if ret < 0: ret = afs_extract_data(call, skb, last, ...); if (ret < 0) return ret; (7) Checks for trailing data and empty final data packets has been consolidated as afs_data_complete(). So: if (skb->len > 0) return -EBADMSG; if (!last) return 0; becomes: ret = afs_data_complete(call, skb, last); if (ret < 0) return ret; (8) afs_transfer_reply() now checks the amount of data it has against the amount of data desired and the amount of data in the skb and returns an error to induce an abort if we don't get exactly what we want. Without these changes, the following oops can occasionally be observed, particularly if some printks are inserted into the delivery path: general protection fault: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 0 PID: 1305 Comm: kworker/u8:3 Tainted: G E 4.7.0-fsdevel+ #1303 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 Workqueue: kafsd afs_async_workfn [kafs] task: ffff88040be041c0 ti: ffff88040c070000 task.ti: ffff88040c070000 RIP: 0010:[<ffffffff8108fd3c>] [<ffffffff8108fd3c>] __lock_acquire+0xcf/0x15a1 RSP: 0018:ffff88040c073bc0 EFLAGS: 00010002 RAX: 6b6b6b6b6b6b6b6b RBX: 0000000000000000 RCX: ffff88040d29a710 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88040d29a710 RBP: ffff88040c073c70 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88040be041c0 R15: ffffffff814c928f FS: 0000000000000000(0000) GS:ffff88041fa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa4595f4750 CR3: 0000000001c14000 CR4: 00000000001406f0 Stack: 0000000000000006 000000000be04930 0000000000000000 ffff880400000000 ffff880400000000 ffffffff8108f847 ffff88040be041c0 ffffffff81050446 ffff8803fc08a920 ffff8803fc08a958 ffff88040be041c0 ffff88040c073c38 Call Trace: [<ffffffff8108f847>] ? mark_held_locks+0x5e/0x74 [<ffffffff81050446>] ? __local_bh_enable_ip+0x9b/0xa1 [<ffffffff8108f9ca>] ? trace_hardirqs_on_caller+0x16d/0x189 [<ffffffff810915f4>] lock_acquire+0x122/0x1b6 [<ffffffff810915f4>] ? lock_acquire+0x122/0x1b6 [<ffffffff814c928f>] ? skb_dequeue+0x18/0x61 [<ffffffff81609dbf>] _raw_spin_lock_irqsave+0x35/0x49 [<ffffffff814c928f>] ? skb_dequeue+0x18/0x61 [<ffffffff814c928f>] skb_dequeue+0x18/0x61 [<ffffffffa009aa92>] afs_deliver_to_call+0x344/0x39d [kafs] [<ffffffffa009ab37>] afs_process_async_call+0x4c/0xd5 [kafs] [<ffffffffa0099e9c>] afs_async_workfn+0xe/0x10 [kafs] [<ffffffff81063a3a>] process_one_work+0x29d/0x57c [<ffffffff81064ac2>] worker_thread+0x24a/0x385 [<ffffffff81064878>] ? rescuer_thread+0x2d0/0x2d0 [<ffffffff810696f5>] kthread+0xf3/0xfb [<ffffffff8160a6ff>] ret_from_fork+0x1f/0x40 [<ffffffff81069602>] ? kthread_create_on_node+0x1cf/0x1cf Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-03 13:11:40 +00:00
atomic_inc(&call->skb_count);
rxrpc: Fix a use-after-push in data_ready handler Fix a use of a packet after it has been enqueued onto the packet processing queue in the data_ready handler. Once on a call's Rx queue, we mustn't touch it any more as it may be dequeued and freed by the call processor running on a work queue. Save the values we need before enqueuing. Without this, we can get an oops like the following: BUG: unable to handle kernel NULL pointer dereference at 000000000000009c IP: [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] PGD 0 Oops: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G E 4.7.0-fsdevel+ #1336 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 task: ffff88040d6863c0 task.stack: ffff88040d68c000 RIP: 0010:[<ffffffffa01854e8>] [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] RSP: 0018:ffff88041fb03a78 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff8803ff195b00 RCX: 0000000000000001 RDX: ffffffffa01854d1 RSI: 0000000000000008 RDI: ffff8803ff195b00 RBP: ffff88041fb03ab0 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88041fb038c8 R11: 0000000000000000 R12: ffff880406874800 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88041fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000009c CR3: 0000000001c14000 CR4: 00000000001406e0 Stack: ffff8803ff195ea0 ffff880408348800 ffff880406874800 ffff8803ff195b00 ffff880408348800 ffff8803ff195ed8 0000000000000000 ffff88041fb03af0 ffffffffa0186072 0000000000000000 ffff8804054da000 0000000000000000 Call Trace: <IRQ> [<ffffffffa0186072>] rxrpc_data_ready+0x89d/0xbae [af_rxrpc] [<ffffffff814c94d7>] __sock_queue_rcv_skb+0x24c/0x2b2 [<ffffffff8155c59a>] __udp_queue_rcv_skb+0x4b/0x1bd [<ffffffff8155e048>] udp_queue_rcv_skb+0x281/0x4db [<ffffffff8155ea8f>] __udp4_lib_rcv+0x7ed/0x963 [<ffffffff8155ef9a>] udp_rcv+0x15/0x17 [<ffffffff81531d86>] ip_local_deliver_finish+0x1c3/0x318 [<ffffffff81532544>] ip_local_deliver+0xbb/0xc4 [<ffffffff81531bc3>] ? inet_del_offload+0x40/0x40 [<ffffffff815322a9>] ip_rcv_finish+0x3ce/0x42c [<ffffffff81532851>] ip_rcv+0x304/0x33d [<ffffffff81531edb>] ? ip_local_deliver_finish+0x318/0x318 [<ffffffff814dff9d>] __netif_receive_skb_core+0x601/0x6e8 [<ffffffff814e072e>] __netif_receive_skb+0x13/0x54 [<ffffffff814e082a>] netif_receive_skb_internal+0xbb/0x17c [<ffffffff814e1838>] napi_gro_receive+0xf9/0x1bd [<ffffffff8144eb9f>] rtl8169_poll+0x32b/0x4a8 [<ffffffff814e1c7b>] net_rx_action+0xe8/0x357 [<ffffffff81051074>] __do_softirq+0x1aa/0x414 [<ffffffff810514ab>] irq_exit+0x3d/0xb0 [<ffffffff810184a2>] do_IRQ+0xe4/0xfc [<ffffffff81612053>] common_interrupt+0x93/0x93 <EOI> [<ffffffff814af837>] ? cpuidle_enter_state+0x1ad/0x2be [<ffffffff814af832>] ? cpuidle_enter_state+0x1a8/0x2be [<ffffffff814af96a>] cpuidle_enter+0x12/0x14 [<ffffffff8108956f>] call_cpuidle+0x39/0x3b [<ffffffff81089855>] cpu_startup_entry+0x230/0x35d [<ffffffff810312ea>] start_secondary+0xf4/0xf7 Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-09 10:30:43 +00:00
terminal = ((flags & RXRPC_LAST_PACKET) &&
!(flags & RXRPC_CLIENT_INITIATED));
ret = rxrpc_queue_rcv_skb(call, skb, false, terminal);
if (ret < 0) {
if (ret == -ENOMEM || ret == -ENOBUFS) {
__clear_bit(ackbit, call->ackr_window);
ack = RXRPC_ACK_NOSPACE;
goto discard_and_ack;
}
goto out;
}
skb = NULL;
rxrpc: Fix a use-after-push in data_ready handler Fix a use of a packet after it has been enqueued onto the packet processing queue in the data_ready handler. Once on a call's Rx queue, we mustn't touch it any more as it may be dequeued and freed by the call processor running on a work queue. Save the values we need before enqueuing. Without this, we can get an oops like the following: BUG: unable to handle kernel NULL pointer dereference at 000000000000009c IP: [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] PGD 0 Oops: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G E 4.7.0-fsdevel+ #1336 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 task: ffff88040d6863c0 task.stack: ffff88040d68c000 RIP: 0010:[<ffffffffa01854e8>] [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] RSP: 0018:ffff88041fb03a78 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff8803ff195b00 RCX: 0000000000000001 RDX: ffffffffa01854d1 RSI: 0000000000000008 RDI: ffff8803ff195b00 RBP: ffff88041fb03ab0 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88041fb038c8 R11: 0000000000000000 R12: ffff880406874800 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88041fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000009c CR3: 0000000001c14000 CR4: 00000000001406e0 Stack: ffff8803ff195ea0 ffff880408348800 ffff880406874800 ffff8803ff195b00 ffff880408348800 ffff8803ff195ed8 0000000000000000 ffff88041fb03af0 ffffffffa0186072 0000000000000000 ffff8804054da000 0000000000000000 Call Trace: <IRQ> [<ffffffffa0186072>] rxrpc_data_ready+0x89d/0xbae [af_rxrpc] [<ffffffff814c94d7>] __sock_queue_rcv_skb+0x24c/0x2b2 [<ffffffff8155c59a>] __udp_queue_rcv_skb+0x4b/0x1bd [<ffffffff8155e048>] udp_queue_rcv_skb+0x281/0x4db [<ffffffff8155ea8f>] __udp4_lib_rcv+0x7ed/0x963 [<ffffffff8155ef9a>] udp_rcv+0x15/0x17 [<ffffffff81531d86>] ip_local_deliver_finish+0x1c3/0x318 [<ffffffff81532544>] ip_local_deliver+0xbb/0xc4 [<ffffffff81531bc3>] ? inet_del_offload+0x40/0x40 [<ffffffff815322a9>] ip_rcv_finish+0x3ce/0x42c [<ffffffff81532851>] ip_rcv+0x304/0x33d [<ffffffff81531edb>] ? ip_local_deliver_finish+0x318/0x318 [<ffffffff814dff9d>] __netif_receive_skb_core+0x601/0x6e8 [<ffffffff814e072e>] __netif_receive_skb+0x13/0x54 [<ffffffff814e082a>] netif_receive_skb_internal+0xbb/0x17c [<ffffffff814e1838>] napi_gro_receive+0xf9/0x1bd [<ffffffff8144eb9f>] rtl8169_poll+0x32b/0x4a8 [<ffffffff814e1c7b>] net_rx_action+0xe8/0x357 [<ffffffff81051074>] __do_softirq+0x1aa/0x414 [<ffffffff810514ab>] irq_exit+0x3d/0xb0 [<ffffffff810184a2>] do_IRQ+0xe4/0xfc [<ffffffff81612053>] common_interrupt+0x93/0x93 <EOI> [<ffffffff814af837>] ? cpuidle_enter_state+0x1ad/0x2be [<ffffffff814af832>] ? cpuidle_enter_state+0x1a8/0x2be [<ffffffff814af96a>] cpuidle_enter+0x12/0x14 [<ffffffff8108956f>] call_cpuidle+0x39/0x3b [<ffffffff81089855>] cpu_startup_entry+0x230/0x35d [<ffffffff810312ea>] start_secondary+0xf4/0xf7 Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-09 10:30:43 +00:00
sp = NULL;
_debug("post #%u", seq);
ASSERTCMP(call->rx_data_post, ==, seq);
call->rx_data_post++;
rxrpc: Fix a use-after-push in data_ready handler Fix a use of a packet after it has been enqueued onto the packet processing queue in the data_ready handler. Once on a call's Rx queue, we mustn't touch it any more as it may be dequeued and freed by the call processor running on a work queue. Save the values we need before enqueuing. Without this, we can get an oops like the following: BUG: unable to handle kernel NULL pointer dereference at 000000000000009c IP: [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] PGD 0 Oops: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G E 4.7.0-fsdevel+ #1336 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 task: ffff88040d6863c0 task.stack: ffff88040d68c000 RIP: 0010:[<ffffffffa01854e8>] [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] RSP: 0018:ffff88041fb03a78 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff8803ff195b00 RCX: 0000000000000001 RDX: ffffffffa01854d1 RSI: 0000000000000008 RDI: ffff8803ff195b00 RBP: ffff88041fb03ab0 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88041fb038c8 R11: 0000000000000000 R12: ffff880406874800 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88041fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000009c CR3: 0000000001c14000 CR4: 00000000001406e0 Stack: ffff8803ff195ea0 ffff880408348800 ffff880406874800 ffff8803ff195b00 ffff880408348800 ffff8803ff195ed8 0000000000000000 ffff88041fb03af0 ffffffffa0186072 0000000000000000 ffff8804054da000 0000000000000000 Call Trace: <IRQ> [<ffffffffa0186072>] rxrpc_data_ready+0x89d/0xbae [af_rxrpc] [<ffffffff814c94d7>] __sock_queue_rcv_skb+0x24c/0x2b2 [<ffffffff8155c59a>] __udp_queue_rcv_skb+0x4b/0x1bd [<ffffffff8155e048>] udp_queue_rcv_skb+0x281/0x4db [<ffffffff8155ea8f>] __udp4_lib_rcv+0x7ed/0x963 [<ffffffff8155ef9a>] udp_rcv+0x15/0x17 [<ffffffff81531d86>] ip_local_deliver_finish+0x1c3/0x318 [<ffffffff81532544>] ip_local_deliver+0xbb/0xc4 [<ffffffff81531bc3>] ? inet_del_offload+0x40/0x40 [<ffffffff815322a9>] ip_rcv_finish+0x3ce/0x42c [<ffffffff81532851>] ip_rcv+0x304/0x33d [<ffffffff81531edb>] ? ip_local_deliver_finish+0x318/0x318 [<ffffffff814dff9d>] __netif_receive_skb_core+0x601/0x6e8 [<ffffffff814e072e>] __netif_receive_skb+0x13/0x54 [<ffffffff814e082a>] netif_receive_skb_internal+0xbb/0x17c [<ffffffff814e1838>] napi_gro_receive+0xf9/0x1bd [<ffffffff8144eb9f>] rtl8169_poll+0x32b/0x4a8 [<ffffffff814e1c7b>] net_rx_action+0xe8/0x357 [<ffffffff81051074>] __do_softirq+0x1aa/0x414 [<ffffffff810514ab>] irq_exit+0x3d/0xb0 [<ffffffff810184a2>] do_IRQ+0xe4/0xfc [<ffffffff81612053>] common_interrupt+0x93/0x93 <EOI> [<ffffffff814af837>] ? cpuidle_enter_state+0x1ad/0x2be [<ffffffff814af832>] ? cpuidle_enter_state+0x1a8/0x2be [<ffffffff814af96a>] cpuidle_enter+0x12/0x14 [<ffffffff8108956f>] call_cpuidle+0x39/0x3b [<ffffffff81089855>] cpu_startup_entry+0x230/0x35d [<ffffffff810312ea>] start_secondary+0xf4/0xf7 Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-09 10:30:43 +00:00
if (flags & RXRPC_LAST_PACKET)
set_bit(RXRPC_CALL_RCVD_LAST, &call->flags);
/* if we've reached an out of sequence packet then we need to drain
* that queue into the socket Rx queue now */
if (call->rx_data_post == call->rx_first_oos) {
_debug("drain rx oos now");
read_lock(&call->state_lock);
if (call->state < RXRPC_CALL_COMPLETE &&
!test_and_set_bit(RXRPC_CALL_EV_DRAIN_RX_OOS, &call->events))
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
rxrpc_queue_call(call);
read_unlock(&call->state_lock);
}
spin_unlock(&call->lock);
atomic_inc(&call->ackr_not_idle);
rxrpc: Fix a use-after-push in data_ready handler Fix a use of a packet after it has been enqueued onto the packet processing queue in the data_ready handler. Once on a call's Rx queue, we mustn't touch it any more as it may be dequeued and freed by the call processor running on a work queue. Save the values we need before enqueuing. Without this, we can get an oops like the following: BUG: unable to handle kernel NULL pointer dereference at 000000000000009c IP: [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] PGD 0 Oops: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G E 4.7.0-fsdevel+ #1336 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 task: ffff88040d6863c0 task.stack: ffff88040d68c000 RIP: 0010:[<ffffffffa01854e8>] [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] RSP: 0018:ffff88041fb03a78 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff8803ff195b00 RCX: 0000000000000001 RDX: ffffffffa01854d1 RSI: 0000000000000008 RDI: ffff8803ff195b00 RBP: ffff88041fb03ab0 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88041fb038c8 R11: 0000000000000000 R12: ffff880406874800 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88041fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000009c CR3: 0000000001c14000 CR4: 00000000001406e0 Stack: ffff8803ff195ea0 ffff880408348800 ffff880406874800 ffff8803ff195b00 ffff880408348800 ffff8803ff195ed8 0000000000000000 ffff88041fb03af0 ffffffffa0186072 0000000000000000 ffff8804054da000 0000000000000000 Call Trace: <IRQ> [<ffffffffa0186072>] rxrpc_data_ready+0x89d/0xbae [af_rxrpc] [<ffffffff814c94d7>] __sock_queue_rcv_skb+0x24c/0x2b2 [<ffffffff8155c59a>] __udp_queue_rcv_skb+0x4b/0x1bd [<ffffffff8155e048>] udp_queue_rcv_skb+0x281/0x4db [<ffffffff8155ea8f>] __udp4_lib_rcv+0x7ed/0x963 [<ffffffff8155ef9a>] udp_rcv+0x15/0x17 [<ffffffff81531d86>] ip_local_deliver_finish+0x1c3/0x318 [<ffffffff81532544>] ip_local_deliver+0xbb/0xc4 [<ffffffff81531bc3>] ? inet_del_offload+0x40/0x40 [<ffffffff815322a9>] ip_rcv_finish+0x3ce/0x42c [<ffffffff81532851>] ip_rcv+0x304/0x33d [<ffffffff81531edb>] ? ip_local_deliver_finish+0x318/0x318 [<ffffffff814dff9d>] __netif_receive_skb_core+0x601/0x6e8 [<ffffffff814e072e>] __netif_receive_skb+0x13/0x54 [<ffffffff814e082a>] netif_receive_skb_internal+0xbb/0x17c [<ffffffff814e1838>] napi_gro_receive+0xf9/0x1bd [<ffffffff8144eb9f>] rtl8169_poll+0x32b/0x4a8 [<ffffffff814e1c7b>] net_rx_action+0xe8/0x357 [<ffffffff81051074>] __do_softirq+0x1aa/0x414 [<ffffffff810514ab>] irq_exit+0x3d/0xb0 [<ffffffff810184a2>] do_IRQ+0xe4/0xfc [<ffffffff81612053>] common_interrupt+0x93/0x93 <EOI> [<ffffffff814af837>] ? cpuidle_enter_state+0x1ad/0x2be [<ffffffff814af832>] ? cpuidle_enter_state+0x1a8/0x2be [<ffffffff814af96a>] cpuidle_enter+0x12/0x14 [<ffffffff8108956f>] call_cpuidle+0x39/0x3b [<ffffffff81089855>] cpu_startup_entry+0x230/0x35d [<ffffffff810312ea>] start_secondary+0xf4/0xf7 Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-09 10:30:43 +00:00
rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, serial, false);
_leave(" = 0 [posted]");
return 0;
protocol_error:
ret = -EBADMSG;
out:
spin_unlock(&call->lock);
_leave(" = %d", ret);
return ret;
discard_and_ack:
_debug("discard and ACK packet %p", skb);
rxrpc: Fix a use-after-push in data_ready handler Fix a use of a packet after it has been enqueued onto the packet processing queue in the data_ready handler. Once on a call's Rx queue, we mustn't touch it any more as it may be dequeued and freed by the call processor running on a work queue. Save the values we need before enqueuing. Without this, we can get an oops like the following: BUG: unable to handle kernel NULL pointer dereference at 000000000000009c IP: [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] PGD 0 Oops: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G E 4.7.0-fsdevel+ #1336 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 task: ffff88040d6863c0 task.stack: ffff88040d68c000 RIP: 0010:[<ffffffffa01854e8>] [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] RSP: 0018:ffff88041fb03a78 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff8803ff195b00 RCX: 0000000000000001 RDX: ffffffffa01854d1 RSI: 0000000000000008 RDI: ffff8803ff195b00 RBP: ffff88041fb03ab0 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88041fb038c8 R11: 0000000000000000 R12: ffff880406874800 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88041fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000009c CR3: 0000000001c14000 CR4: 00000000001406e0 Stack: ffff8803ff195ea0 ffff880408348800 ffff880406874800 ffff8803ff195b00 ffff880408348800 ffff8803ff195ed8 0000000000000000 ffff88041fb03af0 ffffffffa0186072 0000000000000000 ffff8804054da000 0000000000000000 Call Trace: <IRQ> [<ffffffffa0186072>] rxrpc_data_ready+0x89d/0xbae [af_rxrpc] [<ffffffff814c94d7>] __sock_queue_rcv_skb+0x24c/0x2b2 [<ffffffff8155c59a>] __udp_queue_rcv_skb+0x4b/0x1bd [<ffffffff8155e048>] udp_queue_rcv_skb+0x281/0x4db [<ffffffff8155ea8f>] __udp4_lib_rcv+0x7ed/0x963 [<ffffffff8155ef9a>] udp_rcv+0x15/0x17 [<ffffffff81531d86>] ip_local_deliver_finish+0x1c3/0x318 [<ffffffff81532544>] ip_local_deliver+0xbb/0xc4 [<ffffffff81531bc3>] ? inet_del_offload+0x40/0x40 [<ffffffff815322a9>] ip_rcv_finish+0x3ce/0x42c [<ffffffff81532851>] ip_rcv+0x304/0x33d [<ffffffff81531edb>] ? ip_local_deliver_finish+0x318/0x318 [<ffffffff814dff9d>] __netif_receive_skb_core+0x601/0x6e8 [<ffffffff814e072e>] __netif_receive_skb+0x13/0x54 [<ffffffff814e082a>] netif_receive_skb_internal+0xbb/0x17c [<ffffffff814e1838>] napi_gro_receive+0xf9/0x1bd [<ffffffff8144eb9f>] rtl8169_poll+0x32b/0x4a8 [<ffffffff814e1c7b>] net_rx_action+0xe8/0x357 [<ffffffff81051074>] __do_softirq+0x1aa/0x414 [<ffffffff810514ab>] irq_exit+0x3d/0xb0 [<ffffffff810184a2>] do_IRQ+0xe4/0xfc [<ffffffff81612053>] common_interrupt+0x93/0x93 <EOI> [<ffffffff814af837>] ? cpuidle_enter_state+0x1ad/0x2be [<ffffffff814af832>] ? cpuidle_enter_state+0x1a8/0x2be [<ffffffff814af96a>] cpuidle_enter+0x12/0x14 [<ffffffff8108956f>] call_cpuidle+0x39/0x3b [<ffffffff81089855>] cpu_startup_entry+0x230/0x35d [<ffffffff810312ea>] start_secondary+0xf4/0xf7 Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-09 10:30:43 +00:00
__rxrpc_propose_ACK(call, ack, serial, true);
discard:
spin_unlock(&call->lock);
rxrpc_free_skb(skb);
_leave(" = 0 [discarded]");
return 0;
enqueue_and_ack:
rxrpc: Fix a use-after-push in data_ready handler Fix a use of a packet after it has been enqueued onto the packet processing queue in the data_ready handler. Once on a call's Rx queue, we mustn't touch it any more as it may be dequeued and freed by the call processor running on a work queue. Save the values we need before enqueuing. Without this, we can get an oops like the following: BUG: unable to handle kernel NULL pointer dereference at 000000000000009c IP: [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] PGD 0 Oops: 0000 [#1] SMP Modules linked in: kafs(E) af_rxrpc(E) [last unloaded: af_rxrpc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G E 4.7.0-fsdevel+ #1336 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 task: ffff88040d6863c0 task.stack: ffff88040d68c000 RIP: 0010:[<ffffffffa01854e8>] [<ffffffffa01854e8>] rxrpc_fast_process_packet+0x724/0xa11 [af_rxrpc] RSP: 0018:ffff88041fb03a78 EFLAGS: 00010246 RAX: ffffffffffffffff RBX: ffff8803ff195b00 RCX: 0000000000000001 RDX: ffffffffa01854d1 RSI: 0000000000000008 RDI: ffff8803ff195b00 RBP: ffff88041fb03ab0 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88041fb038c8 R11: 0000000000000000 R12: ffff880406874800 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88041fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000009c CR3: 0000000001c14000 CR4: 00000000001406e0 Stack: ffff8803ff195ea0 ffff880408348800 ffff880406874800 ffff8803ff195b00 ffff880408348800 ffff8803ff195ed8 0000000000000000 ffff88041fb03af0 ffffffffa0186072 0000000000000000 ffff8804054da000 0000000000000000 Call Trace: <IRQ> [<ffffffffa0186072>] rxrpc_data_ready+0x89d/0xbae [af_rxrpc] [<ffffffff814c94d7>] __sock_queue_rcv_skb+0x24c/0x2b2 [<ffffffff8155c59a>] __udp_queue_rcv_skb+0x4b/0x1bd [<ffffffff8155e048>] udp_queue_rcv_skb+0x281/0x4db [<ffffffff8155ea8f>] __udp4_lib_rcv+0x7ed/0x963 [<ffffffff8155ef9a>] udp_rcv+0x15/0x17 [<ffffffff81531d86>] ip_local_deliver_finish+0x1c3/0x318 [<ffffffff81532544>] ip_local_deliver+0xbb/0xc4 [<ffffffff81531bc3>] ? inet_del_offload+0x40/0x40 [<ffffffff815322a9>] ip_rcv_finish+0x3ce/0x42c [<ffffffff81532851>] ip_rcv+0x304/0x33d [<ffffffff81531edb>] ? ip_local_deliver_finish+0x318/0x318 [<ffffffff814dff9d>] __netif_receive_skb_core+0x601/0x6e8 [<ffffffff814e072e>] __netif_receive_skb+0x13/0x54 [<ffffffff814e082a>] netif_receive_skb_internal+0xbb/0x17c [<ffffffff814e1838>] napi_gro_receive+0xf9/0x1bd [<ffffffff8144eb9f>] rtl8169_poll+0x32b/0x4a8 [<ffffffff814e1c7b>] net_rx_action+0xe8/0x357 [<ffffffff81051074>] __do_softirq+0x1aa/0x414 [<ffffffff810514ab>] irq_exit+0x3d/0xb0 [<ffffffff810184a2>] do_IRQ+0xe4/0xfc [<ffffffff81612053>] common_interrupt+0x93/0x93 <EOI> [<ffffffff814af837>] ? cpuidle_enter_state+0x1ad/0x2be [<ffffffff814af832>] ? cpuidle_enter_state+0x1a8/0x2be [<ffffffff814af96a>] cpuidle_enter+0x12/0x14 [<ffffffff8108956f>] call_cpuidle+0x39/0x3b [<ffffffff81089855>] cpu_startup_entry+0x230/0x35d [<ffffffff810312ea>] start_secondary+0xf4/0xf7 Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-09 10:30:43 +00:00
__rxrpc_propose_ACK(call, ack, serial, true);
enqueue_packet:
_net("defer skb %p", skb);
spin_unlock(&call->lock);
skb_queue_tail(&call->rx_queue, skb);
atomic_inc(&call->ackr_not_idle);
read_lock(&call->state_lock);
if (call->state < RXRPC_CALL_DEAD)
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
rxrpc_queue_call(call);
read_unlock(&call->state_lock);
_leave(" = 0 [queued]");
return 0;
}
/*
* assume an implicit ACKALL of the transmission phase of a client socket upon
* reception of the first reply packet
*/
static void rxrpc_assume_implicit_ackall(struct rxrpc_call *call, u32 serial)
{
write_lock_bh(&call->state_lock);
switch (call->state) {
case RXRPC_CALL_CLIENT_AWAIT_REPLY:
call->state = RXRPC_CALL_CLIENT_RECV_REPLY;
call->acks_latest = serial;
_debug("implicit ACKALL %%%u", call->acks_latest);
set_bit(RXRPC_CALL_EV_RCVD_ACKALL, &call->events);
write_unlock_bh(&call->state_lock);
if (try_to_del_timer_sync(&call->resend_timer) >= 0) {
clear_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events);
clear_bit(RXRPC_CALL_EV_RESEND, &call->events);
clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
}
break;
default:
write_unlock_bh(&call->state_lock);
break;
}
}
/*
* post an incoming packet to the nominated call to deal with
* - must get rid of the sk_buff, either by freeing it or by queuing it
*/
void rxrpc_fast_process_packet(struct rxrpc_call *call, struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
__be32 wtmp;
u32 hi_serial, abort_code;
_enter("%p,%p", call, skb);
ASSERT(!irqs_disabled());
#if 0 // INJECT RX ERROR
if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA) {
static int skip = 0;
if (++skip == 3) {
printk("DROPPED 3RD PACKET!!!!!!!!!!!!!\n");
skip = 0;
goto free_packet;
}
}
#endif
/* track the latest serial number on this connection for ACK packet
* information */
hi_serial = atomic_read(&call->conn->hi_serial);
while (sp->hdr.serial > hi_serial)
hi_serial = atomic_cmpxchg(&call->conn->hi_serial, hi_serial,
sp->hdr.serial);
/* request ACK generation for any ACK or DATA packet that requests
* it */
if (sp->hdr.flags & RXRPC_REQUEST_ACK) {
_proto("ACK Requested on %%%u", sp->hdr.serial);
rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED, sp->hdr.serial, false);
}
switch (sp->hdr.type) {
case RXRPC_PACKET_TYPE_ABORT:
_debug("abort");
if (skb_copy_bits(skb, 0, &wtmp, sizeof(wtmp)) < 0)
goto protocol_error;
abort_code = ntohl(wtmp);
_proto("Rx ABORT %%%u { %x }", sp->hdr.serial, abort_code);
write_lock_bh(&call->state_lock);
if (call->state < RXRPC_CALL_COMPLETE) {
call->state = RXRPC_CALL_REMOTELY_ABORTED;
call->remote_abort = abort_code;
set_bit(RXRPC_CALL_EV_RCVD_ABORT, &call->events);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
rxrpc_queue_call(call);
}
goto free_packet_unlock;
case RXRPC_PACKET_TYPE_BUSY:
_proto("Rx BUSY %%%u", sp->hdr.serial);
if (rxrpc_conn_is_service(call->conn))
goto protocol_error;
write_lock_bh(&call->state_lock);
switch (call->state) {
case RXRPC_CALL_CLIENT_SEND_REQUEST:
call->state = RXRPC_CALL_SERVER_BUSY;
set_bit(RXRPC_CALL_EV_RCVD_BUSY, &call->events);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
rxrpc_queue_call(call);
case RXRPC_CALL_SERVER_BUSY:
goto free_packet_unlock;
default:
goto protocol_error_locked;
}
default:
_proto("Rx %s %%%u", rxrpc_pkts[sp->hdr.type], sp->hdr.serial);
goto protocol_error;
case RXRPC_PACKET_TYPE_DATA:
_proto("Rx DATA %%%u { #%u }", sp->hdr.serial, sp->hdr.seq);
if (sp->hdr.seq == 0)
goto protocol_error;
call->ackr_prev_seq = sp->hdr.seq;
/* received data implicitly ACKs all of the request packets we
* sent when we're acting as a client */
if (call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY)
rxrpc_assume_implicit_ackall(call, sp->hdr.serial);
switch (rxrpc_fast_process_data(call, skb, sp->hdr.seq)) {
case 0:
skb = NULL;
goto done;
default:
BUG();
/* data packet received beyond the last packet */
case -EBADMSG:
goto protocol_error;
}
case RXRPC_PACKET_TYPE_ACKALL:
case RXRPC_PACKET_TYPE_ACK:
/* ACK processing is done in process context */
read_lock_bh(&call->state_lock);
if (call->state < RXRPC_CALL_DEAD) {
skb_queue_tail(&call->rx_queue, skb);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
rxrpc_queue_call(call);
skb = NULL;
}
read_unlock_bh(&call->state_lock);
goto free_packet;
}
protocol_error:
_debug("protocol error");
write_lock_bh(&call->state_lock);
protocol_error_locked:
if (call->state <= RXRPC_CALL_COMPLETE) {
call->state = RXRPC_CALL_LOCALLY_ABORTED;
call->local_abort = RX_PROTOCOL_ERROR;
set_bit(RXRPC_CALL_EV_ABORT, &call->events);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
rxrpc_queue_call(call);
}
free_packet_unlock:
write_unlock_bh(&call->state_lock);
free_packet:
rxrpc_free_skb(skb);
done:
_leave("");
}
/*
* split up a jumbo data packet
*/
static void rxrpc_process_jumbo_packet(struct rxrpc_call *call,
struct sk_buff *jumbo)
{
struct rxrpc_jumbo_header jhdr;
struct rxrpc_skb_priv *sp;
struct sk_buff *part;
_enter(",{%u,%u}", jumbo->data_len, jumbo->len);
sp = rxrpc_skb(jumbo);
do {
sp->hdr.flags &= ~RXRPC_JUMBO_PACKET;
/* make a clone to represent the first subpacket in what's left
* of the jumbo packet */
part = skb_clone(jumbo, GFP_ATOMIC);
if (!part) {
/* simply ditch the tail in the event of ENOMEM */
pskb_trim(jumbo, RXRPC_JUMBO_DATALEN);
break;
}
rxrpc_new_skb(part);
pskb_trim(part, RXRPC_JUMBO_DATALEN);
if (!pskb_pull(jumbo, RXRPC_JUMBO_DATALEN))
goto protocol_error;
if (skb_copy_bits(jumbo, 0, &jhdr, sizeof(jhdr)) < 0)
goto protocol_error;
if (!pskb_pull(jumbo, sizeof(jhdr)))
BUG();
sp->hdr.seq += 1;
sp->hdr.serial += 1;
sp->hdr.flags = jhdr.flags;
sp->hdr._rsvd = ntohs(jhdr._rsvd);
_proto("Rx DATA Jumbo %%%u", sp->hdr.serial - 1);
rxrpc_fast_process_packet(call, part);
part = NULL;
} while (sp->hdr.flags & RXRPC_JUMBO_PACKET);
rxrpc_fast_process_packet(call, jumbo);
_leave("");
return;
protocol_error:
_debug("protocol error");
rxrpc_free_skb(part);
rxrpc_free_skb(jumbo);
write_lock_bh(&call->state_lock);
if (call->state <= RXRPC_CALL_COMPLETE) {
call->state = RXRPC_CALL_LOCALLY_ABORTED;
call->local_abort = RX_PROTOCOL_ERROR;
set_bit(RXRPC_CALL_EV_ABORT, &call->events);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
rxrpc_queue_call(call);
}
write_unlock_bh(&call->state_lock);
_leave("");
}
/*
* post an incoming packet to the appropriate call/socket to deal with
* - must get rid of the sk_buff, either by freeing it or by queuing it
*/
static void rxrpc_post_packet_to_call(struct rxrpc_call *call,
struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp;
_enter("%p,%p", call, skb);
sp = rxrpc_skb(skb);
_debug("extant call [%d]", call->state);
read_lock(&call->state_lock);
switch (call->state) {
case RXRPC_CALL_LOCALLY_ABORTED:
if (!test_and_set_bit(RXRPC_CALL_EV_ABORT, &call->events)) {
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26 22:50:17 +00:00
rxrpc_queue_call(call);
goto free_unlock;
}
case RXRPC_CALL_REMOTELY_ABORTED:
case RXRPC_CALL_NETWORK_ERROR:
case RXRPC_CALL_DEAD:
goto dead_call;
case RXRPC_CALL_COMPLETE:
case RXRPC_CALL_CLIENT_FINAL_ACK:
/* complete server call */
if (rxrpc_conn_is_service(call->conn))
goto dead_call;
/* resend last packet of a completed call */
_debug("final ack again");
rxrpc_get_call(call);
set_bit(RXRPC_CALL_EV_ACK_FINAL, &call->events);
rxrpc_queue_call(call);
goto free_unlock;
default:
break;
}
read_unlock(&call->state_lock);
rxrpc_get_call(call);
if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
sp->hdr.flags & RXRPC_JUMBO_PACKET)
rxrpc_process_jumbo_packet(call, skb);
else
rxrpc_fast_process_packet(call, skb);
rxrpc_put_call(call);
goto done;
dead_call:
if (sp->hdr.type != RXRPC_PACKET_TYPE_ABORT) {
skb->priority = RX_CALL_DEAD;
rxrpc_reject_packet(call->conn->params.local, skb);
goto unlock;
}
free_unlock:
rxrpc_free_skb(skb);
unlock:
read_unlock(&call->state_lock);
done:
_leave("");
}
/*
* post connection-level events to the connection
* - this includes challenges, responses and some aborts
*/
static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
struct sk_buff *skb)
{
_enter("%p,%p", conn, skb);
skb_queue_tail(&conn->rx_queue, skb);
rxrpc_queue_conn(conn);
}
/*
* post endpoint-level events to the local endpoint
* - this includes debug and version messages
*/
static void rxrpc_post_packet_to_local(struct rxrpc_local *local,
struct sk_buff *skb)
{
_enter("%p,%p", local, skb);
skb_queue_tail(&local->event_queue, skb);
rxrpc_queue_local(local);
}
/*
* Extract the wire header from a packet and translate the byte order.
*/
static noinline
int rxrpc_extract_header(struct rxrpc_skb_priv *sp, struct sk_buff *skb)
{
struct rxrpc_wire_header whdr;
/* dig out the RxRPC connection details */
if (skb_copy_bits(skb, 0, &whdr, sizeof(whdr)) < 0)
return -EBADMSG;
if (!pskb_pull(skb, sizeof(whdr)))
BUG();
memset(sp, 0, sizeof(*sp));
sp->hdr.epoch = ntohl(whdr.epoch);
sp->hdr.cid = ntohl(whdr.cid);
sp->hdr.callNumber = ntohl(whdr.callNumber);
sp->hdr.seq = ntohl(whdr.seq);
sp->hdr.serial = ntohl(whdr.serial);
sp->hdr.flags = whdr.flags;
sp->hdr.type = whdr.type;
sp->hdr.userStatus = whdr.userStatus;
sp->hdr.securityIndex = whdr.securityIndex;
sp->hdr._rsvd = ntohs(whdr._rsvd);
sp->hdr.serviceId = ntohs(whdr.serviceId);
return 0;
}
/*
* handle data received on the local endpoint
* - may be called in interrupt context
rxrpc: Rework local endpoint management Rework the local RxRPC endpoint management. Local endpoint objects are maintained in a flat list as before. This should be okay as there shouldn't be more than one per open AF_RXRPC socket (there can be fewer as local endpoints can be shared if their local service ID is 0 and they share the same local transport parameters). Changes: (1) Local endpoints may now only be shared if they have local service ID 0 (ie. they're not being used for listening). This prevents a scenario where process A is listening of the Cache Manager port and process B contacts a fileserver - which may then attempt to send CM requests back to B. But if A and B are sharing a local endpoint, A will get the CM requests meant for B. (2) We use a mutex to handle lookups and don't provide RCU-only lookups since we only expect to access the list when opening a socket or destroying an endpoint. The local endpoint object is pointed to by the transport socket's sk_user_data for the life of the transport socket - allowing us to refer to it directly from the sk_data_ready and sk_error_report callbacks. (3) atomic_inc_not_zero() now exists and can be used to only share a local endpoint if the last reference hasn't yet gone. (4) We can remove rxrpc_local_lock - a spinlock that had to be taken with BH processing disabled given that we assume sk_user_data won't change under us. (5) The transport socket is shut down before we clear the sk_user_data pointer so that we can be sure that the transport socket's callbacks won't be invoked once the RCU destruction is scheduled. (6) Local endpoints have a work item that handles both destruction and event processing. The means that destruction doesn't then need to wait for event processing. The event queues can then be cleared after the transport socket is shut down. (7) Local endpoints are no longer available for resurrection beyond the life of the sockets that had them open. As soon as their last ref goes, they are scheduled for destruction and may not have their usage count moved from 0. Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-04 13:00:35 +00:00
*
* The socket is locked by the caller and this prevents the socket from being
* shut down and the local endpoint from going away, thus sk_user_data will not
* be cleared until this function returns.
*/
void rxrpc_data_ready(struct sock *sk)
{
struct rxrpc_connection *conn;
struct rxrpc_skb_priv *sp;
rxrpc: Rework local endpoint management Rework the local RxRPC endpoint management. Local endpoint objects are maintained in a flat list as before. This should be okay as there shouldn't be more than one per open AF_RXRPC socket (there can be fewer as local endpoints can be shared if their local service ID is 0 and they share the same local transport parameters). Changes: (1) Local endpoints may now only be shared if they have local service ID 0 (ie. they're not being used for listening). This prevents a scenario where process A is listening of the Cache Manager port and process B contacts a fileserver - which may then attempt to send CM requests back to B. But if A and B are sharing a local endpoint, A will get the CM requests meant for B. (2) We use a mutex to handle lookups and don't provide RCU-only lookups since we only expect to access the list when opening a socket or destroying an endpoint. The local endpoint object is pointed to by the transport socket's sk_user_data for the life of the transport socket - allowing us to refer to it directly from the sk_data_ready and sk_error_report callbacks. (3) atomic_inc_not_zero() now exists and can be used to only share a local endpoint if the last reference hasn't yet gone. (4) We can remove rxrpc_local_lock - a spinlock that had to be taken with BH processing disabled given that we assume sk_user_data won't change under us. (5) The transport socket is shut down before we clear the sk_user_data pointer so that we can be sure that the transport socket's callbacks won't be invoked once the RCU destruction is scheduled. (6) Local endpoints have a work item that handles both destruction and event processing. The means that destruction doesn't then need to wait for event processing. The event queues can then be cleared after the transport socket is shut down. (7) Local endpoints are no longer available for resurrection beyond the life of the sockets that had them open. As soon as their last ref goes, they are scheduled for destruction and may not have their usage count moved from 0. Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-04 13:00:35 +00:00
struct rxrpc_local *local = sk->sk_user_data;
struct sk_buff *skb;
int ret;
_enter("%p", sk);
ASSERT(!irqs_disabled());
skb = skb_recv_datagram(sk, 0, 1, &ret);
if (!skb) {
if (ret == -EAGAIN)
return;
_debug("UDP socket error %d", ret);
return;
}
rxrpc_new_skb(skb);
_net("recv skb %p", skb);
/* we'll probably need to checksum it (didn't call sock_recvmsg) */
if (skb_checksum_complete(skb)) {
rxrpc_free_skb(skb);
__UDP_INC_STATS(&init_net, UDP_MIB_INERRORS, 0);
_leave(" [CSUM failed]");
return;
}
__UDP_INC_STATS(&init_net, UDP_MIB_INDATAGRAMS, 0);
/* The socket buffer we have is owned by UDP, with UDP's data all over
* it, but we really want our own data there.
*/
skb_orphan(skb);
sp = rxrpc_skb(skb);
_net("Rx UDP packet from %08x:%04hu",
ntohl(ip_hdr(skb)->saddr), ntohs(udp_hdr(skb)->source));
/* dig out the RxRPC connection details */
if (rxrpc_extract_header(sp, skb) < 0)
goto bad_message;
_net("Rx RxRPC %s ep=%x call=%x:%x",
sp->hdr.flags & RXRPC_CLIENT_INITIATED ? "ToServer" : "ToClient",
sp->hdr.epoch, sp->hdr.cid, sp->hdr.callNumber);
if (sp->hdr.type >= RXRPC_N_PACKET_TYPES ||
!((RXRPC_SUPPORTED_PACKET_TYPES >> sp->hdr.type) & 1)) {
_proto("Rx Bad Packet Type %u", sp->hdr.type);
goto bad_message;
}
if (sp->hdr.type == RXRPC_PACKET_TYPE_VERSION) {
rxrpc_post_packet_to_local(local, skb);
goto out;
}
if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
(sp->hdr.callNumber == 0 || sp->hdr.seq == 0))
goto bad_message;
rcu_read_lock();
conn = rxrpc_find_connection_rcu(local, skb);
if (!conn)
goto cant_route_call;
if (sp->hdr.callNumber == 0) {
/* Connection-level packet */
_debug("CONN %p {%d}", conn, conn->debug_id);
rxrpc_post_packet_to_conn(conn, skb);
} else {
/* Call-bound packets are routed by connection channel. */
unsigned int channel = sp->hdr.cid & RXRPC_CHANNELMASK;
struct rxrpc_channel *chan = &conn->channels[channel];
struct rxrpc_call *call = rcu_dereference(chan->call);
if (!call || atomic_read(&call->usage) == 0)
goto cant_route_call;
rxrpc_post_packet_to_call(call, skb);
}
rcu_read_unlock();
out:
return;
cant_route_call:
rcu_read_unlock();
_debug("can't route call");
if (sp->hdr.flags & RXRPC_CLIENT_INITIATED &&
sp->hdr.type == RXRPC_PACKET_TYPE_DATA) {
if (sp->hdr.seq == 1) {
_debug("first packet");
skb_queue_tail(&local->accept_queue, skb);
rxrpc: Rework local endpoint management Rework the local RxRPC endpoint management. Local endpoint objects are maintained in a flat list as before. This should be okay as there shouldn't be more than one per open AF_RXRPC socket (there can be fewer as local endpoints can be shared if their local service ID is 0 and they share the same local transport parameters). Changes: (1) Local endpoints may now only be shared if they have local service ID 0 (ie. they're not being used for listening). This prevents a scenario where process A is listening of the Cache Manager port and process B contacts a fileserver - which may then attempt to send CM requests back to B. But if A and B are sharing a local endpoint, A will get the CM requests meant for B. (2) We use a mutex to handle lookups and don't provide RCU-only lookups since we only expect to access the list when opening a socket or destroying an endpoint. The local endpoint object is pointed to by the transport socket's sk_user_data for the life of the transport socket - allowing us to refer to it directly from the sk_data_ready and sk_error_report callbacks. (3) atomic_inc_not_zero() now exists and can be used to only share a local endpoint if the last reference hasn't yet gone. (4) We can remove rxrpc_local_lock - a spinlock that had to be taken with BH processing disabled given that we assume sk_user_data won't change under us. (5) The transport socket is shut down before we clear the sk_user_data pointer so that we can be sure that the transport socket's callbacks won't be invoked once the RCU destruction is scheduled. (6) Local endpoints have a work item that handles both destruction and event processing. The means that destruction doesn't then need to wait for event processing. The event queues can then be cleared after the transport socket is shut down. (7) Local endpoints are no longer available for resurrection beyond the life of the sockets that had them open. As soon as their last ref goes, they are scheduled for destruction and may not have their usage count moved from 0. Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-04 13:00:35 +00:00
rxrpc_queue_work(&local->processor);
_leave(" [incoming]");
return;
}
skb->priority = RX_INVALID_OPERATION;
} else {
skb->priority = RX_CALL_DEAD;
}
if (sp->hdr.type != RXRPC_PACKET_TYPE_ABORT) {
_debug("reject type %d",sp->hdr.type);
rxrpc_reject_packet(local, skb);
} else {
rxrpc_free_skb(skb);
}
_leave(" [no call]");
return;
bad_message:
skb->priority = RX_PROTOCOL_ERROR;
rxrpc_reject_packet(local, skb);
_leave(" [badmsg]");
}