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d41a69f1d3
linux/net/core/sock.c
Eric Dumazet d41a69f1d3 tcp: make tcp_sendmsg() aware of socket backlog 
Large sendmsg()/write() hold socket lock for the duration of the call,
unless sk->sk_sndbuf limit is hit. This is bad because incoming packets
are parked into socket backlog for a long time.
Critical decisions like fast retransmit might be delayed.
Receivers have to maintain a big out of order queue with additional cpu
overhead, and also possible stalls in TX once windows are full.

Bidirectional flows are particularly hurt since the backlog can become
quite big if the copy from user space triggers IO (page faults)

Some applications learnt to use sendmsg() (or sendmmsg()) with small
chunks to avoid this issue.

Kernel should know better, right ?

Add a generic sk_flush_backlog() helper and use it right
before a new skb is allocated. Typically we put 64KB of payload
per skb (unless MSG_EOR is requested) and checking socket backlog
every 64KB gives good results.

As a matter of fact, tests with TSO/GSO disabled give very nice
results, as we manage to keep a small write queue and smaller
perceived rtt.

Note that sk_flush_backlog() maintains socket ownership,
so is not equivalent to a {release_sock(sk); lock_sock(sk);},
to ensure implicit atomicity rules that sendmsg() was
giving to (possibly buggy) applications.

In this simple implementation, I chose to not call tcp_release_cb(),
but we might consider this later.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-02 17:02:26 -04:00

3078 lines
75 KiB
C
Raw Blame History

/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* Generic socket support routines. Memory allocators, socket lock/release
* handler for protocols to use and generic option handler.
*
*
* Authors: Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Florian La Roche, <flla@stud.uni-sb.de>
* Alan Cox, <A.Cox@swansea.ac.uk>
*
* Fixes:
* Alan Cox : Numerous verify_area() problems
* Alan Cox : Connecting on a connecting socket
* now returns an error for tcp.
* Alan Cox : sock->protocol is set correctly.
* and is not sometimes left as 0.
* Alan Cox : connect handles icmp errors on a
* connect properly. Unfortunately there
* is a restart syscall nasty there. I
* can't match BSD without hacking the C
* library. Ideas urgently sought!
* Alan Cox : Disallow bind() to addresses that are
* not ours - especially broadcast ones!!
* Alan Cox : Socket 1024 _IS_ ok for users. (fencepost)
* Alan Cox : sock_wfree/sock_rfree don't destroy sockets,
* instead they leave that for the DESTROY timer.
* Alan Cox : Clean up error flag in accept
* Alan Cox : TCP ack handling is buggy, the DESTROY timer
* was buggy. Put a remove_sock() in the handler
* for memory when we hit 0. Also altered the timer
* code. The ACK stuff can wait and needs major
* TCP layer surgery.
* Alan Cox : Fixed TCP ack bug, removed remove sock
* and fixed timer/inet_bh race.
* Alan Cox : Added zapped flag for TCP
* Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code
* Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
* Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources
* Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing.
* Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
* Rick Sladkey : Relaxed UDP rules for matching packets.
* C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support
* Pauline Middelink : identd support
* Alan Cox : Fixed connect() taking signals I think.
* Alan Cox : SO_LINGER supported
* Alan Cox : Error reporting fixes
* Anonymous : inet_create tidied up (sk->reuse setting)
* Alan Cox : inet sockets don't set sk->type!
* Alan Cox : Split socket option code
* Alan Cox : Callbacks
* Alan Cox : Nagle flag for Charles & Johannes stuff
* Alex : Removed restriction on inet fioctl
* Alan Cox : Splitting INET from NET core
* Alan Cox : Fixed bogus SO_TYPE handling in getsockopt()
* Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code
* Alan Cox : Split IP from generic code
* Alan Cox : New kfree_skbmem()
* Alan Cox : Make SO_DEBUG superuser only.
* Alan Cox : Allow anyone to clear SO_DEBUG
* (compatibility fix)
* Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput.
* Alan Cox : Allocator for a socket is settable.
* Alan Cox : SO_ERROR includes soft errors.
* Alan Cox : Allow NULL arguments on some SO_ opts
* Alan Cox : Generic socket allocation to make hooks
* easier (suggested by Craig Metz).
* Michael Pall : SO_ERROR returns positive errno again
* Steve Whitehouse: Added default destructor to free
* protocol private data.
* Steve Whitehouse: Added various other default routines
* common to several socket families.
* Chris Evans : Call suser() check last on F_SETOWN
* Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
* Andi Kleen : Add sock_kmalloc()/sock_kfree_s()
* Andi Kleen : Fix write_space callback
* Chris Evans : Security fixes - signedness again
* Arnaldo C. Melo : cleanups, use skb_queue_purge
*
* To Fix:
*
*
* 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/capability.h>
#include <linux/errno.h>
#include <linux/errqueue.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/poll.h>
#include <linux/tcp.h>
#include <linux/init.h>
#include <linux/highmem.h>
#include <linux/user_namespace.h>
#include <linux/static_key.h>
#include <linux/memcontrol.h>
#include <linux/prefetch.h>
#include <asm/uaccess.h>
#include <linux/netdevice.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/net_namespace.h>
#include <net/request_sock.h>
#include <net/sock.h>
#include <linux/net_tstamp.h>
#include <net/xfrm.h>
#include <linux/ipsec.h>
#include <net/cls_cgroup.h>
#include <net/netprio_cgroup.h>
#include <linux/sock_diag.h>
#include <linux/filter.h>
#include <net/sock_reuseport.h>
#include <trace/events/sock.h>
#ifdef CONFIG_INET
#include <net/tcp.h>
#endif
#include <net/busy_poll.h>
static DEFINE_MUTEX(proto_list_mutex);
static LIST_HEAD(proto_list);
/**
* sk_ns_capable - General socket capability test
* @sk: Socket to use a capability on or through
* @user_ns: The user namespace of the capability to use
* @cap: The capability to use
*
* Test to see if the opener of the socket had when the socket was
* created and the current process has the capability @cap in the user
* namespace @user_ns.
*/
bool sk_ns_capable(const struct sock *sk,
struct user_namespace *user_ns, int cap)
{
return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
ns_capable(user_ns, cap);
}
EXPORT_SYMBOL(sk_ns_capable);
/**
* sk_capable - Socket global capability test
* @sk: Socket to use a capability on or through
* @cap: The global capability to use
*
* Test to see if the opener of the socket had when the socket was
* created and the current process has the capability @cap in all user
* namespaces.
*/
bool sk_capable(const struct sock *sk, int cap)
{
return sk_ns_capable(sk, &init_user_ns, cap);
}
EXPORT_SYMBOL(sk_capable);
/**
* sk_net_capable - Network namespace socket capability test
* @sk: Socket to use a capability on or through
* @cap: The capability to use
*
* Test to see if the opener of the socket had when the socket was created
* and the current process has the capability @cap over the network namespace
* the socket is a member of.
*/
bool sk_net_capable(const struct sock *sk, int cap)
{
return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
}
EXPORT_SYMBOL(sk_net_capable);
/*
* Each address family might have different locking rules, so we have
* one slock key per address family:
*/
static struct lock_class_key af_family_keys[AF_MAX];
static struct lock_class_key af_family_slock_keys[AF_MAX];
/*
* Make lock validator output more readable. (we pre-construct these
* strings build-time, so that runtime initialization of socket
* locks is fast):
*/
static const char *const af_family_key_strings[AF_MAX+1] = {
"sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" ,
"sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK",
"sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" ,
"sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" ,
"sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" ,
"sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" ,
"sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" ,
"sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" ,
"sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" ,
"sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" ,
"sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
"sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
"sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
"sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_KCM" ,
"sk_lock-AF_MAX"
};
static const char *const af_family_slock_key_strings[AF_MAX+1] = {
"slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
"slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK",
"slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" ,
"slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" ,
"slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" ,
"slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" ,
"slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" ,
"slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" ,
"slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" ,
"slock-27" , "slock-28" , "slock-AF_CAN" ,
"slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
"slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
"slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
"slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_KCM" ,
"slock-AF_MAX"
};
static const char *const af_family_clock_key_strings[AF_MAX+1] = {
"clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
"clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK",
"clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" ,
"clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" ,
"clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" ,
"clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" ,
"clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" ,
"clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" ,
"clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" ,
"clock-27" , "clock-28" , "clock-AF_CAN" ,
"clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
"clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
"clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
"clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_KCM" ,
"clock-AF_MAX"
};
/*
* sk_callback_lock locking rules are per-address-family,
* so split the lock classes by using a per-AF key:
*/
static struct lock_class_key af_callback_keys[AF_MAX];
/* Take into consideration the size of the struct sk_buff overhead in the
* determination of these values, since that is non-constant across
* platforms. This makes socket queueing behavior and performance
* not depend upon such differences.
*/
#define _SK_MEM_PACKETS 256
#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
/* Run time adjustable parameters. */
__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
EXPORT_SYMBOL(sysctl_wmem_max);
__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
EXPORT_SYMBOL(sysctl_rmem_max);
__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
/* Maximal space eaten by iovec or ancillary data plus some space */
int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
EXPORT_SYMBOL(sysctl_optmem_max);
int sysctl_tstamp_allow_data __read_mostly = 1;
struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
EXPORT_SYMBOL_GPL(memalloc_socks);
/**
* sk_set_memalloc - sets %SOCK_MEMALLOC
* @sk: socket to set it on
*
* Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
* It's the responsibility of the admin to adjust min_free_kbytes
* to meet the requirements
*/
void sk_set_memalloc(struct sock *sk)
{
sock_set_flag(sk, SOCK_MEMALLOC);
sk->sk_allocation |= __GFP_MEMALLOC;
static_key_slow_inc(&memalloc_socks);
}
EXPORT_SYMBOL_GPL(sk_set_memalloc);
void sk_clear_memalloc(struct sock *sk)
{
sock_reset_flag(sk, SOCK_MEMALLOC);
sk->sk_allocation &= ~__GFP_MEMALLOC;
static_key_slow_dec(&memalloc_socks);
/*
* SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
* progress of swapping. SOCK_MEMALLOC may be cleared while
* it has rmem allocations due to the last swapfile being deactivated
* but there is a risk that the socket is unusable due to exceeding
* the rmem limits. Reclaim the reserves and obey rmem limits again.
*/
sk_mem_reclaim(sk);
}
EXPORT_SYMBOL_GPL(sk_clear_memalloc);
int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
{
int ret;
unsigned long pflags = current->flags;
/* these should have been dropped before queueing */
BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
current->flags |= PF_MEMALLOC;
ret = sk->sk_backlog_rcv(sk, skb);
tsk_restore_flags(current, pflags, PF_MEMALLOC);
return ret;
}
EXPORT_SYMBOL(__sk_backlog_rcv);
static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
{
struct timeval tv;
if (optlen < sizeof(tv))
return -EINVAL;
if (copy_from_user(&tv, optval, sizeof(tv)))
return -EFAULT;
if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
return -EDOM;
if (tv.tv_sec < 0) {
static int warned __read_mostly;
*timeo_p = 0;
if (warned < 10 && net_ratelimit()) {
warned++;
pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
__func__, current->comm, task_pid_nr(current));
}
return 0;
}
*timeo_p = MAX_SCHEDULE_TIMEOUT;
if (tv.tv_sec == 0 && tv.tv_usec == 0)
return 0;
if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
return 0;
}
static void sock_warn_obsolete_bsdism(const char *name)
{
static int warned;
static char warncomm[TASK_COMM_LEN];
if (strcmp(warncomm, current->comm) && warned < 5) {
strcpy(warncomm, current->comm);
pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
warncomm, name);
warned++;
}
}
static bool sock_needs_netstamp(const struct sock *sk)
{
switch (sk->sk_family) {
case AF_UNSPEC:
case AF_UNIX:
return false;
default:
return true;
}
}
static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
{
if (sk->sk_flags & flags) {
sk->sk_flags &= ~flags;
if (sock_needs_netstamp(sk) &&
!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
net_disable_timestamp();
}
}
int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
unsigned long flags;
struct sk_buff_head *list = &sk->sk_receive_queue;
if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
atomic_inc(&sk->sk_drops);
trace_sock_rcvqueue_full(sk, skb);
return -ENOMEM;
}
if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
atomic_inc(&sk->sk_drops);
return -ENOBUFS;
}
skb->dev = NULL;
skb_set_owner_r(skb, sk);
/* we escape from rcu protected region, make sure we dont leak
* a norefcounted dst
*/
skb_dst_force(skb);
spin_lock_irqsave(&list->lock, flags);
sock_skb_set_dropcount(sk, skb);
__skb_queue_tail(list, skb);
spin_unlock_irqrestore(&list->lock, flags);
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_data_ready(sk);
return 0;
}
EXPORT_SYMBOL(__sock_queue_rcv_skb);
int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
int err;
err = sk_filter(sk, skb);
if (err)
return err;
return __sock_queue_rcv_skb(sk, skb);
}
EXPORT_SYMBOL(sock_queue_rcv_skb);
int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
{
int rc = NET_RX_SUCCESS;
if (sk_filter(sk, skb))
goto discard_and_relse;
skb->dev = NULL;
if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
atomic_inc(&sk->sk_drops);
goto discard_and_relse;
}
if (nested)
bh_lock_sock_nested(sk);
else
bh_lock_sock(sk);
if (!sock_owned_by_user(sk)) {
/*
* trylock + unlock semantics:
*/
mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
rc = sk_backlog_rcv(sk, skb);
mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
bh_unlock_sock(sk);
atomic_inc(&sk->sk_drops);
goto discard_and_relse;
}
bh_unlock_sock(sk);
out:
sock_put(sk);
return rc;
discard_and_relse:
kfree_skb(skb);
goto out;
}
EXPORT_SYMBOL(sk_receive_skb);
struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
{
struct dst_entry *dst = __sk_dst_get(sk);
if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
sk_tx_queue_clear(sk);
RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
dst_release(dst);
return NULL;
}
return dst;
}
EXPORT_SYMBOL(__sk_dst_check);
struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
{
struct dst_entry *dst = sk_dst_get(sk);
if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
sk_dst_reset(sk);
dst_release(dst);
return NULL;
}
return dst;
}
EXPORT_SYMBOL(sk_dst_check);
static int sock_setbindtodevice(struct sock *sk, char __user *optval,
int optlen)
{
int ret = -ENOPROTOOPT;
#ifdef CONFIG_NETDEVICES
struct net *net = sock_net(sk);
char devname[IFNAMSIZ];
int index;
/* Sorry... */
ret = -EPERM;
if (!ns_capable(net->user_ns, CAP_NET_RAW))
goto out;
ret = -EINVAL;
if (optlen < 0)
goto out;
/* Bind this socket to a particular device like "eth0",
* as specified in the passed interface name. If the
* name is "" or the option length is zero the socket
* is not bound.
*/
if (optlen > IFNAMSIZ - 1)
optlen = IFNAMSIZ - 1;
memset(devname, 0, sizeof(devname));
ret = -EFAULT;
if (copy_from_user(devname, optval, optlen))
goto out;
index = 0;
if (devname[0] != '\0') {
struct net_device *dev;
rcu_read_lock();
dev = dev_get_by_name_rcu(net, devname);
if (dev)
index = dev->ifindex;
rcu_read_unlock();
ret = -ENODEV;
if (!dev)
goto out;
}
lock_sock(sk);
sk->sk_bound_dev_if = index;
sk_dst_reset(sk);
release_sock(sk);
ret = 0;
out:
#endif
return ret;
}
static int sock_getbindtodevice(struct sock *sk, char __user *optval,
int __user *optlen, int len)
{
int ret = -ENOPROTOOPT;
#ifdef CONFIG_NETDEVICES
struct net *net = sock_net(sk);
char devname[IFNAMSIZ];
if (sk->sk_bound_dev_if == 0) {
len = 0;
goto zero;
}
ret = -EINVAL;
if (len < IFNAMSIZ)
goto out;
ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
if (ret)
goto out;
len = strlen(devname) + 1;
ret = -EFAULT;
if (copy_to_user(optval, devname, len))
goto out;
zero:
ret = -EFAULT;
if (put_user(len, optlen))
goto out;
ret = 0;
out:
#endif
return ret;
}
static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
{
if (valbool)
sock_set_flag(sk, bit);
else
sock_reset_flag(sk, bit);
}
bool sk_mc_loop(struct sock *sk)
{
if (dev_recursion_level())
return false;
if (!sk)
return true;
switch (sk->sk_family) {
case AF_INET:
return inet_sk(sk)->mc_loop;
#if IS_ENABLED(CONFIG_IPV6)
case AF_INET6:
return inet6_sk(sk)->mc_loop;
#endif
}
WARN_ON(1);
return true;
}
EXPORT_SYMBOL(sk_mc_loop);
/*
* This is meant for all protocols to use and covers goings on
* at the socket level. Everything here is generic.
*/
int sock_setsockopt(struct socket *sock, int level, int optname,
char __user *optval, unsigned int optlen)
{
struct sock *sk = sock->sk;
int val;
int valbool;
struct linger ling;
int ret = 0;
/*
* Options without arguments
*/
if (optname == SO_BINDTODEVICE)
return sock_setbindtodevice(sk, optval, optlen);
if (optlen < sizeof(int))
return -EINVAL;
if (get_user(val, (int __user *)optval))
return -EFAULT;
valbool = val ? 1 : 0;
lock_sock(sk);
switch (optname) {
case SO_DEBUG:
if (val && !capable(CAP_NET_ADMIN))
ret = -EACCES;
else
sock_valbool_flag(sk, SOCK_DBG, valbool);
break;
case SO_REUSEADDR:
sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
break;
case SO_REUSEPORT:
sk->sk_reuseport = valbool;
break;
case SO_TYPE:
case SO_PROTOCOL:
case SO_DOMAIN:
case SO_ERROR:
ret = -ENOPROTOOPT;
break;
case SO_DONTROUTE:
sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
break;
case SO_BROADCAST:
sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
break;
case SO_SNDBUF:
/* Don't error on this BSD doesn't and if you think
* about it this is right. Otherwise apps have to
* play 'guess the biggest size' games. RCVBUF/SNDBUF
* are treated in BSD as hints
*/
val = min_t(u32, val, sysctl_wmem_max);
set_sndbuf:
sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
/* Wake up sending tasks if we upped the value. */
sk->sk_write_space(sk);
break;
case SO_SNDBUFFORCE:
if (!capable(CAP_NET_ADMIN)) {
ret = -EPERM;
break;
}
goto set_sndbuf;
case SO_RCVBUF:
/* Don't error on this BSD doesn't and if you think
* about it this is right. Otherwise apps have to
* play 'guess the biggest size' games. RCVBUF/SNDBUF
* are treated in BSD as hints
*/
val = min_t(u32, val, sysctl_rmem_max);
set_rcvbuf:
sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
/*
* We double it on the way in to account for
* "struct sk_buff" etc. overhead. Applications
* assume that the SO_RCVBUF setting they make will
* allow that much actual data to be received on that
* socket.
*
* Applications are unaware that "struct sk_buff" and
* other overheads allocate from the receive buffer
* during socket buffer allocation.
*
* And after considering the possible alternatives,
* returning the value we actually used in getsockopt
* is the most desirable behavior.
*/
sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
break;
case SO_RCVBUFFORCE:
if (!capable(CAP_NET_ADMIN)) {
ret = -EPERM;
break;
}
goto set_rcvbuf;
case SO_KEEPALIVE:
#ifdef CONFIG_INET
if (sk->sk_protocol == IPPROTO_TCP &&
sk->sk_type == SOCK_STREAM)
tcp_set_keepalive(sk, valbool);
#endif
sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
break;
case SO_OOBINLINE:
sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
break;
case SO_NO_CHECK:
sk->sk_no_check_tx = valbool;
break;
case SO_PRIORITY:
if ((val >= 0 && val <= 6) ||
ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
sk->sk_priority = val;
else
ret = -EPERM;
break;
case SO_LINGER:
if (optlen < sizeof(ling)) {
ret = -EINVAL; /* 1003.1g */
break;
}
if (copy_from_user(&ling, optval, sizeof(ling))) {
ret = -EFAULT;
break;
}
if (!ling.l_onoff)
sock_reset_flag(sk, SOCK_LINGER);
else {
#if (BITS_PER_LONG == 32)
if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
else
#endif
sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
sock_set_flag(sk, SOCK_LINGER);
}
break;
case SO_BSDCOMPAT:
sock_warn_obsolete_bsdism("setsockopt");
break;
case SO_PASSCRED:
if (valbool)
set_bit(SOCK_PASSCRED, &sock->flags);
else
clear_bit(SOCK_PASSCRED, &sock->flags);
break;
case SO_TIMESTAMP:
case SO_TIMESTAMPNS:
if (valbool) {
if (optname == SO_TIMESTAMP)
sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
else
sock_set_flag(sk, SOCK_RCVTSTAMPNS);
sock_set_flag(sk, SOCK_RCVTSTAMP);
sock_enable_timestamp(sk, SOCK_TIMESTAMP);
} else {
sock_reset_flag(sk, SOCK_RCVTSTAMP);
sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
}
break;
case SO_TIMESTAMPING:
if (val & ~SOF_TIMESTAMPING_MASK) {
ret = -EINVAL;
break;
}
if (val & SOF_TIMESTAMPING_OPT_ID &&
!(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
if (sk->sk_protocol == IPPROTO_TCP &&
sk->sk_type == SOCK_STREAM) {
if ((1 << sk->sk_state) &
(TCPF_CLOSE | TCPF_LISTEN)) {
ret = -EINVAL;
break;
}
sk->sk_tskey = tcp_sk(sk)->snd_una;
} else {
sk->sk_tskey = 0;
}
}
sk->sk_tsflags = val;
if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
sock_enable_timestamp(sk,
SOCK_TIMESTAMPING_RX_SOFTWARE);
else
sock_disable_timestamp(sk,
(1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
break;
case SO_RCVLOWAT:
if (val < 0)
val = INT_MAX;
sk->sk_rcvlowat = val ? : 1;
break;
case SO_RCVTIMEO:
ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
break;
case SO_SNDTIMEO:
ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
break;
case SO_ATTACH_FILTER:
ret = -EINVAL;
if (optlen == sizeof(struct sock_fprog)) {
struct sock_fprog fprog;
ret = -EFAULT;
if (copy_from_user(&fprog, optval, sizeof(fprog)))
break;
ret = sk_attach_filter(&fprog, sk);
}
break;
case SO_ATTACH_BPF:
ret = -EINVAL;
if (optlen == sizeof(u32)) {
u32 ufd;
ret = -EFAULT;
if (copy_from_user(&ufd, optval, sizeof(ufd)))
break;
ret = sk_attach_bpf(ufd, sk);
}
break;
case SO_ATTACH_REUSEPORT_CBPF:
ret = -EINVAL;
if (optlen == sizeof(struct sock_fprog)) {
struct sock_fprog fprog;
ret = -EFAULT;
if (copy_from_user(&fprog, optval, sizeof(fprog)))
break;
ret = sk_reuseport_attach_filter(&fprog, sk);
}
break;
case SO_ATTACH_REUSEPORT_EBPF:
ret = -EINVAL;
if (optlen == sizeof(u32)) {
u32 ufd;
ret = -EFAULT;
if (copy_from_user(&ufd, optval, sizeof(ufd)))
break;
ret = sk_reuseport_attach_bpf(ufd, sk);
}
break;
case SO_DETACH_FILTER:
ret = sk_detach_filter(sk);
break;
case SO_LOCK_FILTER:
if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
ret = -EPERM;
else
sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
break;
case SO_PASSSEC:
if (valbool)
set_bit(SOCK_PASSSEC, &sock->flags);
else
clear_bit(SOCK_PASSSEC, &sock->flags);
break;
case SO_MARK:
if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
ret = -EPERM;
else
sk->sk_mark = val;
break;
case SO_RXQ_OVFL:
sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
break;
case SO_WIFI_STATUS:
sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
break;
case SO_PEEK_OFF:
if (sock->ops->set_peek_off)
ret = sock->ops->set_peek_off(sk, val);
else
ret = -EOPNOTSUPP;
break;
case SO_NOFCS:
sock_valbool_flag(sk, SOCK_NOFCS, valbool);
break;
case SO_SELECT_ERR_QUEUE:
sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
break;
#ifdef CONFIG_NET_RX_BUSY_POLL
case SO_BUSY_POLL:
/* allow unprivileged users to decrease the value */
if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
ret = -EPERM;
else {
if (val < 0)
ret = -EINVAL;
else
sk->sk_ll_usec = val;
}
break;
#endif
case SO_MAX_PACING_RATE:
sk->sk_max_pacing_rate = val;
sk->sk_pacing_rate = min(sk->sk_pacing_rate,
sk->sk_max_pacing_rate);
break;
case SO_INCOMING_CPU:
sk->sk_incoming_cpu = val;
break;
case SO_CNX_ADVICE:
if (val == 1)
dst_negative_advice(sk);
break;
default:
ret = -ENOPROTOOPT;
break;
}
release_sock(sk);
return ret;
}
EXPORT_SYMBOL(sock_setsockopt);
static void cred_to_ucred(struct pid *pid, const struct cred *cred,
struct ucred *ucred)
{
ucred->pid = pid_vnr(pid);
ucred->uid = ucred->gid = -1;
if (cred) {
struct user_namespace *current_ns = current_user_ns();
ucred->uid = from_kuid_munged(current_ns, cred->euid);
ucred->gid = from_kgid_munged(current_ns, cred->egid);
}
}
int sock_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
struct sock *sk = sock->sk;
union {
int val;
struct linger ling;
struct timeval tm;
} v;
int lv = sizeof(int);
int len;
if (get_user(len, optlen))
return -EFAULT;
if (len < 0)
return -EINVAL;
memset(&v, 0, sizeof(v));
switch (optname) {
case SO_DEBUG:
v.val = sock_flag(sk, SOCK_DBG);
break;
case SO_DONTROUTE:
v.val = sock_flag(sk, SOCK_LOCALROUTE);
break;
case SO_BROADCAST:
v.val = sock_flag(sk, SOCK_BROADCAST);
break;
case SO_SNDBUF:
v.val = sk->sk_sndbuf;
break;
case SO_RCVBUF:
v.val = sk->sk_rcvbuf;
break;
case SO_REUSEADDR:
v.val = sk->sk_reuse;
break;
case SO_REUSEPORT:
v.val = sk->sk_reuseport;
break;
case SO_KEEPALIVE:
v.val = sock_flag(sk, SOCK_KEEPOPEN);
break;
case SO_TYPE:
v.val = sk->sk_type;
break;
case SO_PROTOCOL:
v.val = sk->sk_protocol;
break;
case SO_DOMAIN:
v.val = sk->sk_family;
break;
case SO_ERROR:
v.val = -sock_error(sk);
if (v.val == 0)
v.val = xchg(&sk->sk_err_soft, 0);
break;
case SO_OOBINLINE:
v.val = sock_flag(sk, SOCK_URGINLINE);
break;
case SO_NO_CHECK:
v.val = sk->sk_no_check_tx;
break;
case SO_PRIORITY:
v.val = sk->sk_priority;
break;
case SO_LINGER:
lv = sizeof(v.ling);
v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
v.ling.l_linger = sk->sk_lingertime / HZ;
break;
case SO_BSDCOMPAT:
sock_warn_obsolete_bsdism("getsockopt");
break;
case SO_TIMESTAMP:
v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
!sock_flag(sk, SOCK_RCVTSTAMPNS);
break;
case SO_TIMESTAMPNS:
v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
break;
case SO_TIMESTAMPING:
v.val = sk->sk_tsflags;
break;
case SO_RCVTIMEO:
lv = sizeof(struct timeval);
if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
v.tm.tv_sec = 0;
v.tm.tv_usec = 0;
} else {
v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
}
break;
case SO_SNDTIMEO:
lv = sizeof(struct timeval);
if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
v.tm.tv_sec = 0;
v.tm.tv_usec = 0;
} else {
v.tm.tv_sec = sk->sk_sndtimeo / HZ;
v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
}
break;
case SO_RCVLOWAT:
v.val = sk->sk_rcvlowat;
break;
case SO_SNDLOWAT:
v.val = 1;
break;
case SO_PASSCRED:
v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
break;
case SO_PEERCRED:
{
struct ucred peercred;
if (len > sizeof(peercred))
len = sizeof(peercred);
cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
if (copy_to_user(optval, &peercred, len))
return -EFAULT;
goto lenout;
}
case SO_PEERNAME:
{
char address[128];
if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
return -ENOTCONN;
if (lv < len)
return -EINVAL;
if (copy_to_user(optval, address, len))
return -EFAULT;
goto lenout;
}
/* Dubious BSD thing... Probably nobody even uses it, but
* the UNIX standard wants it for whatever reason... -DaveM
*/
case SO_ACCEPTCONN:
v.val = sk->sk_state == TCP_LISTEN;
break;
case SO_PASSSEC:
v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
break;
case SO_PEERSEC:
return security_socket_getpeersec_stream(sock, optval, optlen, len);
case SO_MARK:
v.val = sk->sk_mark;
break;
case SO_RXQ_OVFL:
v.val = sock_flag(sk, SOCK_RXQ_OVFL);
break;
case SO_WIFI_STATUS:
v.val = sock_flag(sk, SOCK_WIFI_STATUS);
break;
case SO_PEEK_OFF:
if (!sock->ops->set_peek_off)
return -EOPNOTSUPP;
v.val = sk->sk_peek_off;
break;
case SO_NOFCS:
v.val = sock_flag(sk, SOCK_NOFCS);
break;
case SO_BINDTODEVICE:
return sock_getbindtodevice(sk, optval, optlen, len);
case SO_GET_FILTER:
len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
if (len < 0)
return len;
goto lenout;
case SO_LOCK_FILTER:
v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
break;
case SO_BPF_EXTENSIONS:
v.val = bpf_tell_extensions();
break;
case SO_SELECT_ERR_QUEUE:
v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
break;
#ifdef CONFIG_NET_RX_BUSY_POLL
case SO_BUSY_POLL:
v.val = sk->sk_ll_usec;
break;
#endif
case SO_MAX_PACING_RATE:
v.val = sk->sk_max_pacing_rate;
break;
case SO_INCOMING_CPU:
v.val = sk->sk_incoming_cpu;
break;
default:
/* We implement the SO_SNDLOWAT etc to not be settable
* (1003.1g 7).
*/
return -ENOPROTOOPT;
}
if (len > lv)
len = lv;
if (copy_to_user(optval, &v, len))
return -EFAULT;
lenout:
if (put_user(len, optlen))
return -EFAULT;
return 0;
}
/*
* Initialize an sk_lock.
*
* (We also register the sk_lock with the lock validator.)
*/
static inline void sock_lock_init(struct sock *sk)
{
sock_lock_init_class_and_name(sk,
af_family_slock_key_strings[sk->sk_family],
af_family_slock_keys + sk->sk_family,
af_family_key_strings[sk->sk_family],
af_family_keys + sk->sk_family);
}
/*
* Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
* even temporarly, because of RCU lookups. sk_node should also be left as is.
* We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
*/
static void sock_copy(struct sock *nsk, const struct sock *osk)
{
#ifdef CONFIG_SECURITY_NETWORK
void *sptr = nsk->sk_security;
#endif
memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
#ifdef CONFIG_SECURITY_NETWORK
nsk->sk_security = sptr;
security_sk_clone(osk, nsk);
#endif
}
void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
{
unsigned long nulls1, nulls2;
nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
if (nulls1 > nulls2)
swap(nulls1, nulls2);
if (nulls1 != 0)
memset((char *)sk, 0, nulls1);
memset((char *)sk + nulls1 + sizeof(void *), 0,
nulls2 - nulls1 - sizeof(void *));
memset((char *)sk + nulls2 + sizeof(void *), 0,
size - nulls2 - sizeof(void *));
}
EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
int family)
{
struct sock *sk;
struct kmem_cache *slab;
slab = prot->slab;
if (slab != NULL) {
sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
if (!sk)
return sk;
if (priority & __GFP_ZERO) {
if (prot->clear_sk)
prot->clear_sk(sk, prot->obj_size);
else
sk_prot_clear_nulls(sk, prot->obj_size);
}
} else
sk = kmalloc(prot->obj_size, priority);
if (sk != NULL) {
kmemcheck_annotate_bitfield(sk, flags);
if (security_sk_alloc(sk, family, priority))
goto out_free;
if (!try_module_get(prot->owner))
goto out_free_sec;
sk_tx_queue_clear(sk);
cgroup_sk_alloc(&sk->sk_cgrp_data);
}
return sk;
out_free_sec:
security_sk_free(sk);
out_free:
if (slab != NULL)
kmem_cache_free(slab, sk);
else
kfree(sk);
return NULL;
}
static void sk_prot_free(struct proto *prot, struct sock *sk)
{
struct kmem_cache *slab;
struct module *owner;
owner = prot->owner;
slab = prot->slab;
cgroup_sk_free(&sk->sk_cgrp_data);
security_sk_free(sk);
if (slab != NULL)
kmem_cache_free(slab, sk);
else
kfree(sk);
module_put(owner);
}
/**
* sk_alloc - All socket objects are allocated here
* @net: the applicable net namespace
* @family: protocol family
* @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
* @prot: struct proto associated with this new sock instance
* @kern: is this to be a kernel socket?
*/
struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
struct proto *prot, int kern)
{
struct sock *sk;
sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
if (sk) {
sk->sk_family = family;
/*
* See comment in struct sock definition to understand
* why we need sk_prot_creator -acme
*/
sk->sk_prot = sk->sk_prot_creator = prot;
sock_lock_init(sk);
sk->sk_net_refcnt = kern ? 0 : 1;
if (likely(sk->sk_net_refcnt))
get_net(net);
sock_net_set(sk, net);
atomic_set(&sk->sk_wmem_alloc, 1);
sock_update_classid(&sk->sk_cgrp_data);
sock_update_netprioidx(&sk->sk_cgrp_data);
}
return sk;
}
EXPORT_SYMBOL(sk_alloc);
/* Sockets having SOCK_RCU_FREE will call this function after one RCU
* grace period. This is the case for UDP sockets and TCP listeners.
*/
static void __sk_destruct(struct rcu_head *head)
{
struct sock *sk = container_of(head, struct sock, sk_rcu);
struct sk_filter *filter;
if (sk->sk_destruct)
sk->sk_destruct(sk);
filter = rcu_dereference_check(sk->sk_filter,
atomic_read(&sk->sk_wmem_alloc) == 0);
if (filter) {
sk_filter_uncharge(sk, filter);
RCU_INIT_POINTER(sk->sk_filter, NULL);
}
if (rcu_access_pointer(sk->sk_reuseport_cb))
reuseport_detach_sock(sk);
sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
if (atomic_read(&sk->sk_omem_alloc))
pr_debug("%s: optmem leakage (%d bytes) detected\n",
__func__, atomic_read(&sk->sk_omem_alloc));
if (sk->sk_peer_cred)
put_cred(sk->sk_peer_cred);
put_pid(sk->sk_peer_pid);
if (likely(sk->sk_net_refcnt))
put_net(sock_net(sk));
sk_prot_free(sk->sk_prot_creator, sk);
}
void sk_destruct(struct sock *sk)
{
if (sock_flag(sk, SOCK_RCU_FREE))
call_rcu(&sk->sk_rcu, __sk_destruct);
else
__sk_destruct(&sk->sk_rcu);
}
static void __sk_free(struct sock *sk)
{
if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
sock_diag_broadcast_destroy(sk);
else
sk_destruct(sk);
}
void sk_free(struct sock *sk)
{
/*
* We subtract one from sk_wmem_alloc and can know if
* some packets are still in some tx queue.
* If not null, sock_wfree() will call __sk_free(sk) later
*/
if (atomic_dec_and_test(&sk->sk_wmem_alloc))
__sk_free(sk);
}
EXPORT_SYMBOL(sk_free);
/**
* sk_clone_lock - clone a socket, and lock its clone
* @sk: the socket to clone
* @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
*
* Caller must unlock socket even in error path (bh_unlock_sock(newsk))
*/
struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
{
struct sock *newsk;
bool is_charged = true;
newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
if (newsk != NULL) {
struct sk_filter *filter;
sock_copy(newsk, sk);
/* SANITY */
if (likely(newsk->sk_net_refcnt))
get_net(sock_net(newsk));
sk_node_init(&newsk->sk_node);
sock_lock_init(newsk);
bh_lock_sock(newsk);
newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
newsk->sk_backlog.len = 0;
atomic_set(&newsk->sk_rmem_alloc, 0);
/*
* sk_wmem_alloc set to one (see sk_free() and sock_wfree())
*/
atomic_set(&newsk->sk_wmem_alloc, 1);
atomic_set(&newsk->sk_omem_alloc, 0);
skb_queue_head_init(&newsk->sk_receive_queue);
skb_queue_head_init(&newsk->sk_write_queue);
rwlock_init(&newsk->sk_callback_lock);
lockdep_set_class_and_name(&newsk->sk_callback_lock,
af_callback_keys + newsk->sk_family,
af_family_clock_key_strings[newsk->sk_family]);
newsk->sk_dst_cache = NULL;
newsk->sk_wmem_queued = 0;
newsk->sk_forward_alloc = 0;
atomic_set(&newsk->sk_drops, 0);
newsk->sk_send_head = NULL;
newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
sock_reset_flag(newsk, SOCK_DONE);
skb_queue_head_init(&newsk->sk_error_queue);
filter = rcu_dereference_protected(newsk->sk_filter, 1);
if (filter != NULL)
/* though it's an empty new sock, the charging may fail
* if sysctl_optmem_max was changed between creation of
* original socket and cloning
*/
is_charged = sk_filter_charge(newsk, filter);
if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
/* It is still raw copy of parent, so invalidate
* destructor and make plain sk_free() */
newsk->sk_destruct = NULL;
bh_unlock_sock(newsk);
sk_free(newsk);
newsk = NULL;
goto out;
}
RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
newsk->sk_err = 0;
newsk->sk_priority = 0;
newsk->sk_incoming_cpu = raw_smp_processor_id();
atomic64_set(&newsk->sk_cookie, 0);
/*
* Before updating sk_refcnt, we must commit prior changes to memory
* (Documentation/RCU/rculist_nulls.txt for details)
*/
smp_wmb();
atomic_set(&newsk->sk_refcnt, 2);
/*
* Increment the counter in the same struct proto as the master
* sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
* is the same as sk->sk_prot->socks, as this field was copied
* with memcpy).
*
* This _changes_ the previous behaviour, where
* tcp_create_openreq_child always was incrementing the
* equivalent to tcp_prot->socks (inet_sock_nr), so this have
* to be taken into account in all callers. -acme
*/
sk_refcnt_debug_inc(newsk);
sk_set_socket(newsk, NULL);
newsk->sk_wq = NULL;
if (mem_cgroup_sockets_enabled && sk->sk_memcg)
sock_update_memcg(newsk);
if (newsk->sk_prot->sockets_allocated)
sk_sockets_allocated_inc(newsk);
if (sock_needs_netstamp(sk) &&
newsk->sk_flags & SK_FLAGS_TIMESTAMP)
net_enable_timestamp();
}
out:
return newsk;
}
EXPORT_SYMBOL_GPL(sk_clone_lock);
void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
{
u32 max_segs = 1;
sk_dst_set(sk, dst);
sk->sk_route_caps = dst->dev->features;
if (sk->sk_route_caps & NETIF_F_GSO)
sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
sk->sk_route_caps &= ~sk->sk_route_nocaps;
if (sk_can_gso(sk)) {
if (dst->header_len) {
sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
} else {
sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
sk->sk_gso_max_size = dst->dev->gso_max_size;
max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
}
}
sk->sk_gso_max_segs = max_segs;
}
EXPORT_SYMBOL_GPL(sk_setup_caps);
/*
* Simple resource managers for sockets.
*/
/*
* Write buffer destructor automatically called from kfree_skb.
*/
void sock_wfree(struct sk_buff *skb)
{
struct sock *sk = skb->sk;
unsigned int len = skb->truesize;
if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
/*
* Keep a reference on sk_wmem_alloc, this will be released
* after sk_write_space() call
*/
atomic_sub(len - 1, &sk->sk_wmem_alloc);
sk->sk_write_space(sk);
len = 1;
}
/*
* if sk_wmem_alloc reaches 0, we must finish what sk_free()
* could not do because of in-flight packets
*/
if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
__sk_free(sk);
}
EXPORT_SYMBOL(sock_wfree);
void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
{
skb_orphan(skb);
skb->sk = sk;
#ifdef CONFIG_INET
if (unlikely(!sk_fullsock(sk))) {
skb->destructor = sock_edemux;
sock_hold(sk);
return;
}
#endif
skb->destructor = sock_wfree;
skb_set_hash_from_sk(skb, sk);
/*
* We used to take a refcount on sk, but following operation
* is enough to guarantee sk_free() wont free this sock until
* all in-flight packets are completed
*/
atomic_add(skb->truesize, &sk->sk_wmem_alloc);
}
EXPORT_SYMBOL(skb_set_owner_w);
void skb_orphan_partial(struct sk_buff *skb)
{
/* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
* so we do not completely orphan skb, but transfert all
* accounted bytes but one, to avoid unexpected reorders.
*/
if (skb->destructor == sock_wfree
#ifdef CONFIG_INET
|| skb->destructor == tcp_wfree
#endif
) {
atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
skb->truesize = 1;
} else {
skb_orphan(skb);
}
}
EXPORT_SYMBOL(skb_orphan_partial);
/*
* Read buffer destructor automatically called from kfree_skb.
*/
void sock_rfree(struct sk_buff *skb)
{
struct sock *sk = skb->sk;
unsigned int len = skb->truesize;
atomic_sub(len, &sk->sk_rmem_alloc);
sk_mem_uncharge(sk, len);
}
EXPORT_SYMBOL(sock_rfree);
/*
* Buffer destructor for skbs that are not used directly in read or write
* path, e.g. for error handler skbs. Automatically called from kfree_skb.
*/
void sock_efree(struct sk_buff *skb)
{
sock_put(skb->sk);
}
EXPORT_SYMBOL(sock_efree);
kuid_t sock_i_uid(struct sock *sk)
{
kuid_t uid;
read_lock_bh(&sk->sk_callback_lock);
uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
read_unlock_bh(&sk->sk_callback_lock);
return uid;
}
EXPORT_SYMBOL(sock_i_uid);
unsigned long sock_i_ino(struct sock *sk)
{
unsigned long ino;
read_lock_bh(&sk->sk_callback_lock);
ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
read_unlock_bh(&sk->sk_callback_lock);
return ino;
}
EXPORT_SYMBOL(sock_i_ino);
/*
* Allocate a skb from the socket's send buffer.
*/
struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
gfp_t priority)
{
if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
struct sk_buff *skb = alloc_skb(size, priority);
if (skb) {
skb_set_owner_w(skb, sk);
return skb;
}
}
return NULL;
}
EXPORT_SYMBOL(sock_wmalloc);
/*
* Allocate a memory block from the socket's option memory buffer.
*/
void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
{
if ((unsigned int)size <= sysctl_optmem_max &&
atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
void *mem;
/* First do the add, to avoid the race if kmalloc
* might sleep.
*/
atomic_add(size, &sk->sk_omem_alloc);
mem = kmalloc(size, priority);
if (mem)
return mem;
atomic_sub(size, &sk->sk_omem_alloc);
}
return NULL;
}
EXPORT_SYMBOL(sock_kmalloc);
/* Free an option memory block. Note, we actually want the inline
* here as this allows gcc to detect the nullify and fold away the
* condition entirely.
*/
static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
const bool nullify)
{
if (WARN_ON_ONCE(!mem))
return;
if (nullify)
kzfree(mem);
else
kfree(mem);
atomic_sub(size, &sk->sk_omem_alloc);
}
void sock_kfree_s(struct sock *sk, void *mem, int size)
{
__sock_kfree_s(sk, mem, size, false);
}
EXPORT_SYMBOL(sock_kfree_s);
void sock_kzfree_s(struct sock *sk, void *mem, int size)
{
__sock_kfree_s(sk, mem, size, true);
}
EXPORT_SYMBOL(sock_kzfree_s);
/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
I think, these locks should be removed for datagram sockets.
*/
static long sock_wait_for_wmem(struct sock *sk, long timeo)
{
DEFINE_WAIT(wait);
sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
for (;;) {
if (!timeo)
break;
if (signal_pending(current))
break;
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
break;
if (sk->sk_shutdown & SEND_SHUTDOWN)
break;
if (sk->sk_err)
break;
timeo = schedule_timeout(timeo);
}
finish_wait(sk_sleep(sk), &wait);
return timeo;
}
/*
* Generic send/receive buffer handlers
*/
struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
unsigned long data_len, int noblock,
int *errcode, int max_page_order)
{
struct sk_buff *skb;
long timeo;
int err;
timeo = sock_sndtimeo(sk, noblock);
for (;;) {
err = sock_error(sk);
if (err != 0)
goto failure;
err = -EPIPE;
if (sk->sk_shutdown & SEND_SHUTDOWN)
goto failure;
if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
break;
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
err = -EAGAIN;
if (!timeo)
goto failure;
if (signal_pending(current))
goto interrupted;
timeo = sock_wait_for_wmem(sk, timeo);
}
skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
errcode, sk->sk_allocation);
if (skb)
skb_set_owner_w(skb, sk);
return skb;
interrupted:
err = sock_intr_errno(timeo);
failure:
*errcode = err;
return NULL;
}
EXPORT_SYMBOL(sock_alloc_send_pskb);
struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
int noblock, int *errcode)
{
return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
}
EXPORT_SYMBOL(sock_alloc_send_skb);
int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
struct sockcm_cookie *sockc)
{
u32 tsflags;
switch (cmsg->cmsg_type) {
case SO_MARK:
if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
return -EPERM;
if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
return -EINVAL;
sockc->mark = *(u32 *)CMSG_DATA(cmsg);
break;
case SO_TIMESTAMPING:
if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
return -EINVAL;
tsflags = *(u32 *)CMSG_DATA(cmsg);
if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
return -EINVAL;
sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
sockc->tsflags |= tsflags;
break;
default:
return -EINVAL;
}
return 0;
}
EXPORT_SYMBOL(__sock_cmsg_send);
int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
struct sockcm_cookie *sockc)
{
struct cmsghdr *cmsg;
int ret;
for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
if (cmsg->cmsg_level != SOL_SOCKET)
continue;
ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
if (ret)
return ret;
}
return 0;
}
EXPORT_SYMBOL(sock_cmsg_send);
/* On 32bit arches, an skb frag is limited to 2^15 */
#define SKB_FRAG_PAGE_ORDER get_order(32768)
/**
* skb_page_frag_refill - check that a page_frag contains enough room
* @sz: minimum size of the fragment we want to get
* @pfrag: pointer to page_frag
* @gfp: priority for memory allocation
*
* Note: While this allocator tries to use high order pages, there is
* no guarantee that allocations succeed. Therefore, @sz MUST be
* less or equal than PAGE_SIZE.
*/
bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
{
if (pfrag->page) {
if (page_ref_count(pfrag->page) == 1) {
pfrag->offset = 0;
return true;
}
if (pfrag->offset + sz <= pfrag->size)
return true;
put_page(pfrag->page);
}
pfrag->offset = 0;
if (SKB_FRAG_PAGE_ORDER) {
/* Avoid direct reclaim but allow kswapd to wake */
pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
__GFP_COMP | __GFP_NOWARN |
__GFP_NORETRY,
SKB_FRAG_PAGE_ORDER);
if (likely(pfrag->page)) {
pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
return true;
}
}
pfrag->page = alloc_page(gfp);
if (likely(pfrag->page)) {
pfrag->size = PAGE_SIZE;
return true;
}
return false;
}
EXPORT_SYMBOL(skb_page_frag_refill);
bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
{
if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
return true;
sk_enter_memory_pressure(sk);
sk_stream_moderate_sndbuf(sk);
return false;
}
EXPORT_SYMBOL(sk_page_frag_refill);
static void __lock_sock(struct sock *sk)
__releases(&sk->sk_lock.slock)
__acquires(&sk->sk_lock.slock)
{
DEFINE_WAIT(wait);
for (;;) {
prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
TASK_UNINTERRUPTIBLE);
spin_unlock_bh(&sk->sk_lock.slock);
schedule();
spin_lock_bh(&sk->sk_lock.slock);
if (!sock_owned_by_user(sk))
break;
}
finish_wait(&sk->sk_lock.wq, &wait);
}
static void __release_sock(struct sock *sk)
__releases(&sk->sk_lock.slock)
__acquires(&sk->sk_lock.slock)
{
struct sk_buff *skb, *next;
while ((skb = sk->sk_backlog.head) != NULL) {
sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
spin_unlock_bh(&sk->sk_lock.slock);
do {
next = skb->next;
prefetch(next);
WARN_ON_ONCE(skb_dst_is_noref(skb));
skb->next = NULL;
sk_backlog_rcv(sk, skb);
cond_resched();
skb = next;
} while (skb != NULL);
spin_lock_bh(&sk->sk_lock.slock);
}
/*
* Doing the zeroing here guarantee we can not loop forever
* while a wild producer attempts to flood us.
*/
sk->sk_backlog.len = 0;
}
void __sk_flush_backlog(struct sock *sk)
{
spin_lock_bh(&sk->sk_lock.slock);
__release_sock(sk);
spin_unlock_bh(&sk->sk_lock.slock);
}
/**
* sk_wait_data - wait for data to arrive at sk_receive_queue
* @sk: sock to wait on
* @timeo: for how long
* @skb: last skb seen on sk_receive_queue
*
* Now socket state including sk->sk_err is changed only under lock,
* hence we may omit checks after joining wait queue.
* We check receive queue before schedule() only as optimization;
* it is very likely that release_sock() added new data.
*/
int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
{
int rc;
DEFINE_WAIT(wait);
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb);
sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
finish_wait(sk_sleep(sk), &wait);
return rc;
}
EXPORT_SYMBOL(sk_wait_data);
/**
* __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
* @sk: socket
* @size: memory size to allocate
* @kind: allocation type
*
* If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
* rmem allocation. This function assumes that protocols which have
* memory_pressure use sk_wmem_queued as write buffer accounting.
*/
int __sk_mem_schedule(struct sock *sk, int size, int kind)
{
struct proto *prot = sk->sk_prot;
int amt = sk_mem_pages(size);
long allocated;
sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
allocated = sk_memory_allocated_add(sk, amt);
if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
!mem_cgroup_charge_skmem(sk->sk_memcg, amt))
goto suppress_allocation;
/* Under limit. */
if (allocated <= sk_prot_mem_limits(sk, 0)) {
sk_leave_memory_pressure(sk);
return 1;
}
/* Under pressure. */
if (allocated > sk_prot_mem_limits(sk, 1))
sk_enter_memory_pressure(sk);
/* Over hard limit. */
if (allocated > sk_prot_mem_limits(sk, 2))
goto suppress_allocation;
/* guarantee minimum buffer size under pressure */
if (kind == SK_MEM_RECV) {
if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
return 1;
} else { /* SK_MEM_SEND */
if (sk->sk_type == SOCK_STREAM) {
if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
return 1;
} else if (atomic_read(&sk->sk_wmem_alloc) <
prot->sysctl_wmem[0])
return 1;
}
if (sk_has_memory_pressure(sk)) {
int alloc;
if (!sk_under_memory_pressure(sk))
return 1;
alloc = sk_sockets_allocated_read_positive(sk);
if (sk_prot_mem_limits(sk, 2) > alloc *
sk_mem_pages(sk->sk_wmem_queued +
atomic_read(&sk->sk_rmem_alloc) +
sk->sk_forward_alloc))
return 1;
}
suppress_allocation:
if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
sk_stream_moderate_sndbuf(sk);
/* Fail only if socket is _under_ its sndbuf.
* In this case we cannot block, so that we have to fail.
*/
if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
return 1;
}
trace_sock_exceed_buf_limit(sk, prot, allocated);
/* Alas. Undo changes. */
sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
sk_memory_allocated_sub(sk, amt);
if (mem_cgroup_sockets_enabled && sk->sk_memcg)
mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
return 0;
}
EXPORT_SYMBOL(__sk_mem_schedule);
/**
* __sk_mem_reclaim - reclaim memory_allocated
* @sk: socket
* @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
*/
void __sk_mem_reclaim(struct sock *sk, int amount)
{
amount >>= SK_MEM_QUANTUM_SHIFT;
sk_memory_allocated_sub(sk, amount);
sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
if (mem_cgroup_sockets_enabled && sk->sk_memcg)
mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
if (sk_under_memory_pressure(sk) &&
(sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
sk_leave_memory_pressure(sk);
}
EXPORT_SYMBOL(__sk_mem_reclaim);
int sk_set_peek_off(struct sock *sk, int val)
{
if (val < 0)
return -EINVAL;
sk->sk_peek_off = val;
return 0;
}
EXPORT_SYMBOL_GPL(sk_set_peek_off);
/*
* Set of default routines for initialising struct proto_ops when
* the protocol does not support a particular function. In certain
* cases where it makes no sense for a protocol to have a "do nothing"
* function, some default processing is provided.
*/
int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_bind);
int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
int len, int flags)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_connect);
int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_socketpair);
int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_accept);
int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
int *len, int peer)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_getname);
unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
{
return 0;
}
EXPORT_SYMBOL(sock_no_poll);
int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_ioctl);
int sock_no_listen(struct socket *sock, int backlog)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_listen);
int sock_no_shutdown(struct socket *sock, int how)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_shutdown);
int sock_no_setsockopt(struct socket *sock, int level, int optname,
char __user *optval, unsigned int optlen)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_setsockopt);
int sock_no_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_getsockopt);
int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_sendmsg);
int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
int flags)
{
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(sock_no_recvmsg);
int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
{
/* Mirror missing mmap method error code */
return -ENODEV;
}
EXPORT_SYMBOL(sock_no_mmap);
ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
{
ssize_t res;
struct msghdr msg = {.msg_flags = flags};
struct kvec iov;
char *kaddr = kmap(page);
iov.iov_base = kaddr + offset;
iov.iov_len = size;
res = kernel_sendmsg(sock, &msg, &iov, 1, size);
kunmap(page);
return res;
}
EXPORT_SYMBOL(sock_no_sendpage);
/*
* Default Socket Callbacks
*/
static void sock_def_wakeup(struct sock *sk)
{
struct socket_wq *wq;
rcu_read_lock();
wq = rcu_dereference(sk->sk_wq);
if (skwq_has_sleeper(wq))
wake_up_interruptible_all(&wq->wait);
rcu_read_unlock();
}
static void sock_def_error_report(struct sock *sk)
{
struct socket_wq *wq;
rcu_read_lock();
wq = rcu_dereference(sk->sk_wq);
if (skwq_has_sleeper(wq))
wake_up_interruptible_poll(&wq->wait, POLLERR);
sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
rcu_read_unlock();
}
static void sock_def_readable(struct sock *sk)
{
struct socket_wq *wq;
rcu_read_lock();
wq = rcu_dereference(sk->sk_wq);
if (skwq_has_sleeper(wq))
wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
POLLRDNORM | POLLRDBAND);
sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
rcu_read_unlock();
}
static void sock_def_write_space(struct sock *sk)
{
struct socket_wq *wq;
rcu_read_lock();
/* Do not wake up a writer until he can make "significant"
* progress. --DaveM
*/
if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
wq = rcu_dereference(sk->sk_wq);
if (skwq_has_sleeper(wq))
wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
POLLWRNORM | POLLWRBAND);
/* Should agree with poll, otherwise some programs break */
if (sock_writeable(sk))
sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
}
rcu_read_unlock();
}
static void sock_def_destruct(struct sock *sk)
{
}
void sk_send_sigurg(struct sock *sk)
{
if (sk->sk_socket && sk->sk_socket->file)
if (send_sigurg(&sk->sk_socket->file->f_owner))
sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
}
EXPORT_SYMBOL(sk_send_sigurg);
void sk_reset_timer(struct sock *sk, struct timer_list* timer,
unsigned long expires)
{
if (!mod_timer(timer, expires))
sock_hold(sk);
}
EXPORT_SYMBOL(sk_reset_timer);
void sk_stop_timer(struct sock *sk, struct timer_list* timer)
{
if (del_timer(timer))
__sock_put(sk);
}
EXPORT_SYMBOL(sk_stop_timer);
void sock_init_data(struct socket *sock, struct sock *sk)
{
skb_queue_head_init(&sk->sk_receive_queue);
skb_queue_head_init(&sk->sk_write_queue);
skb_queue_head_init(&sk->sk_error_queue);
sk->sk_send_head = NULL;
init_timer(&sk->sk_timer);
sk->sk_allocation = GFP_KERNEL;
sk->sk_rcvbuf = sysctl_rmem_default;
sk->sk_sndbuf = sysctl_wmem_default;
sk->sk_state = TCP_CLOSE;
sk_set_socket(sk, sock);
sock_set_flag(sk, SOCK_ZAPPED);
if (sock) {
sk->sk_type = sock->type;
sk->sk_wq = sock->wq;
sock->sk = sk;
} else
sk->sk_wq = NULL;
rwlock_init(&sk->sk_callback_lock);
lockdep_set_class_and_name(&sk->sk_callback_lock,
af_callback_keys + sk->sk_family,
af_family_clock_key_strings[sk->sk_family]);
sk->sk_state_change = sock_def_wakeup;
sk->sk_data_ready = sock_def_readable;
sk->sk_write_space = sock_def_write_space;
sk->sk_error_report = sock_def_error_report;
sk->sk_destruct = sock_def_destruct;
sk->sk_frag.page = NULL;
sk->sk_frag.offset = 0;
sk->sk_peek_off = -1;
sk->sk_peer_pid = NULL;
sk->sk_peer_cred = NULL;
sk->sk_write_pending = 0;
sk->sk_rcvlowat = 1;
sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
sk->sk_stamp = ktime_set(-1L, 0);
#ifdef CONFIG_NET_RX_BUSY_POLL
sk->sk_napi_id = 0;
sk->sk_ll_usec = sysctl_net_busy_read;
#endif
sk->sk_max_pacing_rate = ~0U;
sk->sk_pacing_rate = ~0U;
sk->sk_incoming_cpu = -1;
/*
* Before updating sk_refcnt, we must commit prior changes to memory
* (Documentation/RCU/rculist_nulls.txt for details)
*/
smp_wmb();
atomic_set(&sk->sk_refcnt, 1);
atomic_set(&sk->sk_drops, 0);
}
EXPORT_SYMBOL(sock_init_data);
void lock_sock_nested(struct sock *sk, int subclass)
{
might_sleep();
spin_lock_bh(&sk->sk_lock.slock);
if (sk->sk_lock.owned)
__lock_sock(sk);
sk->sk_lock.owned = 1;
spin_unlock(&sk->sk_lock.slock);
/*
* The sk_lock has mutex_lock() semantics here:
*/
mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
local_bh_enable();
}
EXPORT_SYMBOL(lock_sock_nested);
void release_sock(struct sock *sk)
{
spin_lock_bh(&sk->sk_lock.slock);
if (sk->sk_backlog.tail)
__release_sock(sk);
/* Warning : release_cb() might need to release sk ownership,
* ie call sock_release_ownership(sk) before us.
*/
if (sk->sk_prot->release_cb)
sk->sk_prot->release_cb(sk);
sock_release_ownership(sk);
if (waitqueue_active(&sk->sk_lock.wq))
wake_up(&sk->sk_lock.wq);
spin_unlock_bh(&sk->sk_lock.slock);
}
EXPORT_SYMBOL(release_sock);
/**
* lock_sock_fast - fast version of lock_sock
* @sk: socket
*
* This version should be used for very small section, where process wont block
* return false if fast path is taken
* sk_lock.slock locked, owned = 0, BH disabled
* return true if slow path is taken
* sk_lock.slock unlocked, owned = 1, BH enabled
*/
bool lock_sock_fast(struct sock *sk)
{
might_sleep();
spin_lock_bh(&sk->sk_lock.slock);
if (!sk->sk_lock.owned)
/*
* Note : We must disable BH
*/
return false;
__lock_sock(sk);
sk->sk_lock.owned = 1;
spin_unlock(&sk->sk_lock.slock);
/*
* The sk_lock has mutex_lock() semantics here:
*/
mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
local_bh_enable();
return true;
}
EXPORT_SYMBOL(lock_sock_fast);
int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
{
struct timeval tv;
if (!sock_flag(sk, SOCK_TIMESTAMP))
sock_enable_timestamp(sk, SOCK_TIMESTAMP);
tv = ktime_to_timeval(sk->sk_stamp);
if (tv.tv_sec == -1)
return -ENOENT;
if (tv.tv_sec == 0) {
sk->sk_stamp = ktime_get_real();
tv = ktime_to_timeval(sk->sk_stamp);
}
return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
}
EXPORT_SYMBOL(sock_get_timestamp);
int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
{
struct timespec ts;
if (!sock_flag(sk, SOCK_TIMESTAMP))
sock_enable_timestamp(sk, SOCK_TIMESTAMP);
ts = ktime_to_timespec(sk->sk_stamp);
if (ts.tv_sec == -1)
return -ENOENT;
if (ts.tv_sec == 0) {
sk->sk_stamp = ktime_get_real();
ts = ktime_to_timespec(sk->sk_stamp);
}
return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
}
EXPORT_SYMBOL(sock_get_timestampns);
void sock_enable_timestamp(struct sock *sk, int flag)
{
if (!sock_flag(sk, flag)) {
unsigned long previous_flags = sk->sk_flags;
sock_set_flag(sk, flag);
/*
* we just set one of the two flags which require net
* time stamping, but time stamping might have been on
* already because of the other one
*/
if (sock_needs_netstamp(sk) &&
!(previous_flags & SK_FLAGS_TIMESTAMP))
net_enable_timestamp();
}
}
int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
int level, int type)
{
struct sock_exterr_skb *serr;
struct sk_buff *skb;
int copied, err;
err = -EAGAIN;
skb = sock_dequeue_err_skb(sk);
if (skb == NULL)
goto out;
copied = skb->len;
if (copied > len) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
err = skb_copy_datagram_msg(skb, 0, msg, copied);
if (err)
goto out_free_skb;
sock_recv_timestamp(msg, sk, skb);
serr = SKB_EXT_ERR(skb);
put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
out_free_skb:
kfree_skb(skb);
out:
return err;
}
EXPORT_SYMBOL(sock_recv_errqueue);
/*
* Get a socket option on an socket.
*
* FIX: POSIX 1003.1g is very ambiguous here. It states that
* asynchronous errors should be reported by getsockopt. We assume
* this means if you specify SO_ERROR (otherwise whats the point of it).
*/
int sock_common_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
struct sock *sk = sock->sk;
return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
}
EXPORT_SYMBOL(sock_common_getsockopt);
#ifdef CONFIG_COMPAT
int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
struct sock *sk = sock->sk;
if (sk->sk_prot->compat_getsockopt != NULL)
return sk->sk_prot->compat_getsockopt(sk, level, optname,
optval, optlen);
return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
}
EXPORT_SYMBOL(compat_sock_common_getsockopt);
#endif
int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
int flags)
{
struct sock *sk = sock->sk;
int addr_len = 0;
int err;
err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
flags & ~MSG_DONTWAIT, &addr_len);
if (err >= 0)
msg->msg_namelen = addr_len;
return err;
}
EXPORT_SYMBOL(sock_common_recvmsg);
/*
* Set socket options on an inet socket.
*/
int sock_common_setsockopt(struct socket *sock, int level, int optname,
char __user *optval, unsigned int optlen)
{
struct sock *sk = sock->sk;
return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
}
EXPORT_SYMBOL(sock_common_setsockopt);
#ifdef CONFIG_COMPAT
int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
char __user *optval, unsigned int optlen)
{
struct sock *sk = sock->sk;
if (sk->sk_prot->compat_setsockopt != NULL)
return sk->sk_prot->compat_setsockopt(sk, level, optname,
optval, optlen);
return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
}
EXPORT_SYMBOL(compat_sock_common_setsockopt);
#endif
void sk_common_release(struct sock *sk)
{
if (sk->sk_prot->destroy)
sk->sk_prot->destroy(sk);
/*
* Observation: when sock_common_release is called, processes have
* no access to socket. But net still has.
* Step one, detach it from networking:
*
* A. Remove from hash tables.
*/
sk->sk_prot->unhash(sk);
/*
* In this point socket cannot receive new packets, but it is possible
* that some packets are in flight because some CPU runs receiver and
* did hash table lookup before we unhashed socket. They will achieve
* receive queue and will be purged by socket destructor.
*
* Also we still have packets pending on receive queue and probably,
* our own packets waiting in device queues. sock_destroy will drain
* receive queue, but transmitted packets will delay socket destruction
* until the last reference will be released.
*/
sock_orphan(sk);
xfrm_sk_free_policy(sk);
sk_refcnt_debug_release(sk);
if (sk->sk_frag.page) {
put_page(sk->sk_frag.page);
sk->sk_frag.page = NULL;
}
sock_put(sk);
}
EXPORT_SYMBOL(sk_common_release);
#ifdef CONFIG_PROC_FS
#define PROTO_INUSE_NR 64 /* should be enough for the first time */
struct prot_inuse {
int val[PROTO_INUSE_NR];
};
static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
#ifdef CONFIG_NET_NS
void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
{
__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
}
EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
int sock_prot_inuse_get(struct net *net, struct proto *prot)
{
int cpu, idx = prot->inuse_idx;
int res = 0;
for_each_possible_cpu(cpu)
res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
return res >= 0 ? res : 0;
}
EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
static int __net_init sock_inuse_init_net(struct net *net)
{
net->core.inuse = alloc_percpu(struct prot_inuse);
return net->core.inuse ? 0 : -ENOMEM;
}
static void __net_exit sock_inuse_exit_net(struct net *net)
{
free_percpu(net->core.inuse);
}
static struct pernet_operations net_inuse_ops = {
.init = sock_inuse_init_net,
.exit = sock_inuse_exit_net,
};
static __init int net_inuse_init(void)
{
if (register_pernet_subsys(&net_inuse_ops))
panic("Cannot initialize net inuse counters");
return 0;
}
core_initcall(net_inuse_init);
#else
static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
{
__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
}
EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
int sock_prot_inuse_get(struct net *net, struct proto *prot)
{
int cpu, idx = prot->inuse_idx;
int res = 0;
for_each_possible_cpu(cpu)
res += per_cpu(prot_inuse, cpu).val[idx];
return res >= 0 ? res : 0;
}
EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
#endif
static void assign_proto_idx(struct proto *prot)
{
prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
pr_err("PROTO_INUSE_NR exhausted\n");
return;
}
set_bit(prot->inuse_idx, proto_inuse_idx);
}
static void release_proto_idx(struct proto *prot)
{
if (prot->inuse_idx != PROTO_INUSE_NR - 1)
clear_bit(prot->inuse_idx, proto_inuse_idx);
}
#else
static inline void assign_proto_idx(struct proto *prot)
{
}
static inline void release_proto_idx(struct proto *prot)
{
}
#endif
static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
{
if (!rsk_prot)
return;
kfree(rsk_prot->slab_name);
rsk_prot->slab_name = NULL;
kmem_cache_destroy(rsk_prot->slab);
rsk_prot->slab = NULL;
}
static int req_prot_init(const struct proto *prot)
{
struct request_sock_ops *rsk_prot = prot->rsk_prot;
if (!rsk_prot)
return 0;
rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
prot->name);
if (!rsk_prot->slab_name)
return -ENOMEM;
rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
rsk_prot->obj_size, 0,
prot->slab_flags, NULL);
if (!rsk_prot->slab) {
pr_crit("%s: Can't create request sock SLAB cache!\n",
prot->name);
return -ENOMEM;
}
return 0;
}
int proto_register(struct proto *prot, int alloc_slab)
{
if (alloc_slab) {
prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
SLAB_HWCACHE_ALIGN | prot->slab_flags,
NULL);
if (prot->slab == NULL) {
pr_crit("%s: Can't create sock SLAB cache!\n",
prot->name);
goto out;
}
if (req_prot_init(prot))
goto out_free_request_sock_slab;
if (prot->twsk_prot != NULL) {
prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
if (prot->twsk_prot->twsk_slab_name == NULL)
goto out_free_request_sock_slab;
prot->twsk_prot->twsk_slab =
kmem_cache_create(prot->twsk_prot->twsk_slab_name,
prot->twsk_prot->twsk_obj_size,
0,
prot->slab_flags,
NULL);
if (prot->twsk_prot->twsk_slab == NULL)
goto out_free_timewait_sock_slab_name;
}
}
mutex_lock(&proto_list_mutex);
list_add(&prot->node, &proto_list);
assign_proto_idx(prot);
mutex_unlock(&proto_list_mutex);
return 0;
out_free_timewait_sock_slab_name:
kfree(prot->twsk_prot->twsk_slab_name);
out_free_request_sock_slab:
req_prot_cleanup(prot->rsk_prot);
kmem_cache_destroy(prot->slab);
prot->slab = NULL;
out:
return -ENOBUFS;
}
EXPORT_SYMBOL(proto_register);
void proto_unregister(struct proto *prot)
{
mutex_lock(&proto_list_mutex);
release_proto_idx(prot);
list_del(&prot->node);
mutex_unlock(&proto_list_mutex);
kmem_cache_destroy(prot->slab);
prot->slab = NULL;
req_prot_cleanup(prot->rsk_prot);
if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
kmem_cache_destroy(prot->twsk_prot->twsk_slab);
kfree(prot->twsk_prot->twsk_slab_name);
prot->twsk_prot->twsk_slab = NULL;
}
}
EXPORT_SYMBOL(proto_unregister);
#ifdef CONFIG_PROC_FS
static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
__acquires(proto_list_mutex)
{
mutex_lock(&proto_list_mutex);
return seq_list_start_head(&proto_list, *pos);
}
static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
return seq_list_next(v, &proto_list, pos);
}
static void proto_seq_stop(struct seq_file *seq, void *v)
__releases(proto_list_mutex)
{
mutex_unlock(&proto_list_mutex);
}
static char proto_method_implemented(const void *method)
{
return method == NULL ? 'n' : 'y';
}
static long sock_prot_memory_allocated(struct proto *proto)
{
return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
}
static char *sock_prot_memory_pressure(struct proto *proto)
{
return proto->memory_pressure != NULL ?
proto_memory_pressure(proto) ? "yes" : "no" : "NI";
}
static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
{
seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
proto->name,
proto->obj_size,
sock_prot_inuse_get(seq_file_net(seq), proto),
sock_prot_memory_allocated(proto),
sock_prot_memory_pressure(proto),
proto->max_header,
proto->slab == NULL ? "no" : "yes",
module_name(proto->owner),
proto_method_implemented(proto->close),
proto_method_implemented(proto->connect),
proto_method_implemented(proto->disconnect),
proto_method_implemented(proto->accept),
proto_method_implemented(proto->ioctl),
proto_method_implemented(proto->init),
proto_method_implemented(proto->destroy),
proto_method_implemented(proto->shutdown),
proto_method_implemented(proto->setsockopt),
proto_method_implemented(proto->getsockopt),
proto_method_implemented(proto->sendmsg),
proto_method_implemented(proto->recvmsg),
proto_method_implemented(proto->sendpage),
proto_method_implemented(proto->bind),
proto_method_implemented(proto->backlog_rcv),
proto_method_implemented(proto->hash),
proto_method_implemented(proto->unhash),
proto_method_implemented(proto->get_port),
proto_method_implemented(proto->enter_memory_pressure));
}
static int proto_seq_show(struct seq_file *seq, void *v)
{
if (v == &proto_list)
seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
"protocol",
"size",
"sockets",
"memory",
"press",
"maxhdr",
"slab",
"module",
"cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
else
proto_seq_printf(seq, list_entry(v, struct proto, node));
return 0;
}
static const struct seq_operations proto_seq_ops = {
.start = proto_seq_start,
.next = proto_seq_next,
.stop = proto_seq_stop,
.show = proto_seq_show,
};
static int proto_seq_open(struct inode *inode, struct file *file)
{
return seq_open_net(inode, file, &proto_seq_ops,
sizeof(struct seq_net_private));
}
static const struct file_operations proto_seq_fops = {
.owner = THIS_MODULE,
.open = proto_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_net,
};
static __net_init int proto_init_net(struct net *net)
{
if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
return -ENOMEM;
return 0;
}
static __net_exit void proto_exit_net(struct net *net)
{
remove_proc_entry("protocols", net->proc_net);
}
static __net_initdata struct pernet_operations proto_net_ops = {
.init = proto_init_net,
.exit = proto_exit_net,
};
static int __init proto_init(void)
{
return register_pernet_subsys(&proto_net_ops);
}
subsys_initcall(proto_init);
#endif /* PROC_FS */
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