linux/include/net/net_namespace.h

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Operations on the network namespace
*/
#ifndef __NET_NET_NAMESPACE_H
#define __NET_NET_NAMESPACE_H
#include <linux/atomic.h>
#include <linux/refcount.h>
#include <linux/workqueue.h>
#include <linux/list.h>
#include <linux/sysctl.h>
#include <linux/uidgid.h>
#include <net/flow.h>
#include <net/netns/core.h>
#include <net/netns/mib.h>
#include <net/netns/unix.h>
#include <net/netns/packet.h>
#include <net/netns/ipv4.h>
#include <net/netns/ipv6.h>
#include <net/netns/nexthop.h>
#include <net/netns/ieee802154_6lowpan.h>
#include <net/netns/sctp.h>
#include <net/netns/dccp.h>
#include <net/netns/netfilter.h>
#include <net/netns/x_tables.h>
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
#include <net/netns/conntrack.h>
#endif
#include <net/netns/nftables.h>
#include <net/netns/xfrm.h>
mpls: Basic routing support This change adds a new Kconfig option MPLS_ROUTING. The core of this change is the code to look at an mpls packet received from another machine. Look that packet up in a routing table and forward the packet on. Support of MPLS over ATM is not considered or attempted here. This implemntation follows RFC3032 and implements the MPLS shim header that can pass over essentially any network. What RFC3021 refers to as the as the Incoming Label Map (ILM) I call net->mpls.platform_label[]. What RFC3031 refers to as the Next Label Hop Forwarding Entry (NHLFE) I call mpls_route. Though calling it the label fordwarding information base (lfib) might also be valid. Further the implemntation forwards packets as described in RFC3032. There is no need and given the original motivation for MPLS a strong discincentive to have a flexible label forwarding path. In essence the logic is the topmost label is read, looked up, removed, and replaced by 0 or more new lables and the sent out the specified interface to it's next hop. Quite a few optional features are not implemented here. Among them are generation of ICMP errors when the TTL is exceeded or the packet is larger than the next hop MTU (those conditions are detected and the packets are dropped instead of generating an icmp error). The traffic class field is always set to 0. The implementation focuses on IP over MPLS and does not handle egress of other kinds of protocols. Instead of implementing coordination with the neighbour table and sorting out how to input next hops in a different address family (for which there is value). I was lazy and implemented a next hop mac address instead. The code is simpler and there are flavor of MPLS such as MPLS-TP where neither an IPv4 nor an IPv6 next hop is appropriate so a next hop by mac address would need to be implemented at some point. Two new definitions AF_MPLS and PF_MPLS are exposed to userspace. Decoding the mpls header must be done by first byeswapping a 32bit bit endian word into the local cpu endian and then bit shifting to extract the pieces. There is no C bit-field that can represent a wire format mpls header on a little endian machine as the low bits of the 20bit label wind up in the wrong half of third byte. Therefore internally everything is deal with in cpu native byte order except when writing to and reading from a packet. For management simplicity if a label is configured to forward out an interface that is down the packet is dropped early. Similarly if an network interface is removed rt_dev is updated to NULL (so no reference is preserved) and any packets for that label are dropped. Keeping the label entries in the kernel allows the kernel label table to function as the definitive source of which labels are allocated and which are not. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04 01:10:47 +00:00
#include <net/netns/mpls.h>
#include <net/netns/can.h>
#include <net/netns/xdp.h>
#include <net/netns/bpf.h>
#include <linux/ns_common.h>
#include <linux/idr.h>
#include <linux/skbuff.h>
#include <linux/notifier.h>
struct user_namespace;
struct proc_dir_entry;
struct net_device;
struct sock;
struct ctl_table_header;
struct net_generic;
struct uevent_sock;
struct netns_ipvs;
struct bpf_prog;
#define NETDEV_HASHBITS 8
#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
struct net {
/* First cache line can be often dirtied.
* Do not place here read-mostly fields.
*/
refcount_t passive; /* To decide when the network
* namespace should be freed.
*/
spinlock_t rules_mod_lock;
unsigned int dev_unreg_count;
unsigned int dev_base_seq; /* protected by rtnl_mutex */
int ifindex;
spinlock_t nsid_lock;
atomic_t fnhe_genid;
struct list_head list; /* list of network namespaces */
struct list_head exit_list; /* To linked to call pernet exit
* methods on dead net (
* pernet_ops_rwsem read locked),
* or to unregister pernet ops
* (pernet_ops_rwsem write locked).
*/
struct llist_node cleanup_list; /* namespaces on death row */
#ifdef CONFIG_KEYS
struct key_tag *key_domain; /* Key domain of operation tag */
#endif
struct user_namespace *user_ns; /* Owning user namespace */
struct ucounts *ucounts;
struct idr netns_ids;
struct ns_common ns;
struct list_head dev_base_head;
struct proc_dir_entry *proc_net;
struct proc_dir_entry *proc_net_stat;
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 18:56:21 +00:00
#ifdef CONFIG_SYSCTL
struct ctl_table_set sysctls;
#endif
struct sock *rtnl; /* rtnetlink socket */
struct sock *genl_sock;
struct uevent_sock *uevent_sock; /* uevent socket */
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 18:56:21 +00:00
struct hlist_head *dev_name_head;
struct hlist_head *dev_index_head;
struct raw_notifier_head netdev_chain;
/* Note that @hash_mix can be read millions times per second,
* it is critical that it is on a read_mostly cache line.
*/
u32 hash_mix;
struct net_device *loopback_dev; /* The loopback */
/* core fib_rules */
struct list_head rules_ops;
struct netns_core core;
struct netns_mib mib;
struct netns_packet packet;
struct netns_unix unx;
struct netns_nexthop nexthop;
struct netns_ipv4 ipv4;
#if IS_ENABLED(CONFIG_IPV6)
struct netns_ipv6 ipv6;
#endif
#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
struct netns_ieee802154_lowpan ieee802154_lowpan;
#endif
#if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
struct netns_sctp sctp;
#endif
#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
struct netns_dccp dccp;
#endif
#ifdef CONFIG_NETFILTER
struct netns_nf nf;
struct netns_xt xt;
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
struct netns_ct ct;
#endif
#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
struct netns_nftables nft;
#endif
#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
struct netns_nf_frag nf_frag;
struct ctl_table_header *nf_frag_frags_hdr;
#endif
struct sock *nfnl;
struct sock *nfnl_stash;
#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
struct list_head nfct_timeout_list;
#endif
#endif
#ifdef CONFIG_WEXT_CORE
struct sk_buff_head wext_nlevents;
#endif
struct net_generic __rcu *gen;
/* Used to store attached BPF programs */
struct netns_bpf bpf;
/* Note : following structs are cache line aligned */
#ifdef CONFIG_XFRM
struct netns_xfrm xfrm;
#endif
bpf: Add netns cookie and enable it for bpf cgroup hooks In Cilium we're mainly using BPF cgroup hooks today in order to implement kube-proxy free Kubernetes service translation for ClusterIP, NodePort (*), ExternalIP, and LoadBalancer as well as HostPort mapping [0] for all traffic between Cilium managed nodes. While this works in its current shape and avoids packet-level NAT for inter Cilium managed node traffic, there is one major limitation we're facing today, that is, lack of netns awareness. In Kubernetes, the concept of Pods (which hold one or multiple containers) has been built around network namespaces, so while we can use the global scope of attaching to root BPF cgroup hooks also to our advantage (e.g. for exposing NodePort ports on loopback addresses), we also have the need to differentiate between initial network namespaces and non-initial one. For example, ExternalIP services mandate that non-local service IPs are not to be translated from the host (initial) network namespace as one example. Right now, we have an ugly work-around in place where non-local service IPs for ExternalIP services are not xlated from connect() and friends BPF hooks but instead via less efficient packet-level NAT on the veth tc ingress hook for Pod traffic. On top of determining whether we're in initial or non-initial network namespace we also have a need for a socket-cookie like mechanism for network namespaces scope. Socket cookies have the nice property that they can be combined as part of the key structure e.g. for BPF LRU maps without having to worry that the cookie could be recycled. We are planning to use this for our sessionAffinity implementation for services. Therefore, add a new bpf_get_netns_cookie() helper which would resolve both use cases at once: bpf_get_netns_cookie(NULL) would provide the cookie for the initial network namespace while passing the context instead of NULL would provide the cookie from the application's network namespace. We're using a hole, so no size increase; the assignment happens only once. Therefore this allows for a comparison on initial namespace as well as regular cookie usage as we have today with socket cookies. We could later on enable this helper for other program types as well as we would see need. (*) Both externalTrafficPolicy={Local|Cluster} types [0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.c Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/c47d2346982693a9cf9da0e12690453aded4c788.1585323121.git.daniel@iogearbox.net
2020-03-27 15:58:52 +00:00
u64 net_cookie; /* written once */
bpf: Add netns cookie and enable it for bpf cgroup hooks In Cilium we're mainly using BPF cgroup hooks today in order to implement kube-proxy free Kubernetes service translation for ClusterIP, NodePort (*), ExternalIP, and LoadBalancer as well as HostPort mapping [0] for all traffic between Cilium managed nodes. While this works in its current shape and avoids packet-level NAT for inter Cilium managed node traffic, there is one major limitation we're facing today, that is, lack of netns awareness. In Kubernetes, the concept of Pods (which hold one or multiple containers) has been built around network namespaces, so while we can use the global scope of attaching to root BPF cgroup hooks also to our advantage (e.g. for exposing NodePort ports on loopback addresses), we also have the need to differentiate between initial network namespaces and non-initial one. For example, ExternalIP services mandate that non-local service IPs are not to be translated from the host (initial) network namespace as one example. Right now, we have an ugly work-around in place where non-local service IPs for ExternalIP services are not xlated from connect() and friends BPF hooks but instead via less efficient packet-level NAT on the veth tc ingress hook for Pod traffic. On top of determining whether we're in initial or non-initial network namespace we also have a need for a socket-cookie like mechanism for network namespaces scope. Socket cookies have the nice property that they can be combined as part of the key structure e.g. for BPF LRU maps without having to worry that the cookie could be recycled. We are planning to use this for our sessionAffinity implementation for services. Therefore, add a new bpf_get_netns_cookie() helper which would resolve both use cases at once: bpf_get_netns_cookie(NULL) would provide the cookie for the initial network namespace while passing the context instead of NULL would provide the cookie from the application's network namespace. We're using a hole, so no size increase; the assignment happens only once. Therefore this allows for a comparison on initial namespace as well as regular cookie usage as we have today with socket cookies. We could later on enable this helper for other program types as well as we would see need. (*) Both externalTrafficPolicy={Local|Cluster} types [0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.c Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/c47d2346982693a9cf9da0e12690453aded4c788.1585323121.git.daniel@iogearbox.net
2020-03-27 15:58:52 +00:00
#if IS_ENABLED(CONFIG_IP_VS)
struct netns_ipvs *ipvs;
mpls: Basic routing support This change adds a new Kconfig option MPLS_ROUTING. The core of this change is the code to look at an mpls packet received from another machine. Look that packet up in a routing table and forward the packet on. Support of MPLS over ATM is not considered or attempted here. This implemntation follows RFC3032 and implements the MPLS shim header that can pass over essentially any network. What RFC3021 refers to as the as the Incoming Label Map (ILM) I call net->mpls.platform_label[]. What RFC3031 refers to as the Next Label Hop Forwarding Entry (NHLFE) I call mpls_route. Though calling it the label fordwarding information base (lfib) might also be valid. Further the implemntation forwards packets as described in RFC3032. There is no need and given the original motivation for MPLS a strong discincentive to have a flexible label forwarding path. In essence the logic is the topmost label is read, looked up, removed, and replaced by 0 or more new lables and the sent out the specified interface to it's next hop. Quite a few optional features are not implemented here. Among them are generation of ICMP errors when the TTL is exceeded or the packet is larger than the next hop MTU (those conditions are detected and the packets are dropped instead of generating an icmp error). The traffic class field is always set to 0. The implementation focuses on IP over MPLS and does not handle egress of other kinds of protocols. Instead of implementing coordination with the neighbour table and sorting out how to input next hops in a different address family (for which there is value). I was lazy and implemented a next hop mac address instead. The code is simpler and there are flavor of MPLS such as MPLS-TP where neither an IPv4 nor an IPv6 next hop is appropriate so a next hop by mac address would need to be implemented at some point. Two new definitions AF_MPLS and PF_MPLS are exposed to userspace. Decoding the mpls header must be done by first byeswapping a 32bit bit endian word into the local cpu endian and then bit shifting to extract the pieces. There is no C bit-field that can represent a wire format mpls header on a little endian machine as the low bits of the 20bit label wind up in the wrong half of third byte. Therefore internally everything is deal with in cpu native byte order except when writing to and reading from a packet. For management simplicity if a label is configured to forward out an interface that is down the packet is dropped early. Similarly if an network interface is removed rt_dev is updated to NULL (so no reference is preserved) and any packets for that label are dropped. Keeping the label entries in the kernel allows the kernel label table to function as the definitive source of which labels are allocated and which are not. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04 01:10:47 +00:00
#endif
#if IS_ENABLED(CONFIG_MPLS)
struct netns_mpls mpls;
#endif
#if IS_ENABLED(CONFIG_CAN)
struct netns_can can;
#endif
#ifdef CONFIG_XDP_SOCKETS
struct netns_xdp xdp;
#endif
#if IS_ENABLED(CONFIG_CRYPTO_USER)
struct sock *crypto_nlsk;
#endif
struct sock *diag_nlsk;
} __randomize_layout;
#include <linux/seq_file_net.h>
/* Init's network namespace */
extern struct net init_net;
#ifdef CONFIG_NET_NS
struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
struct net *old_net);
void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
void net_ns_barrier(void);
#else /* CONFIG_NET_NS */
#include <linux/sched.h>
#include <linux/nsproxy.h>
static inline struct net *copy_net_ns(unsigned long flags,
struct user_namespace *user_ns, struct net *old_net)
{
if (flags & CLONE_NEWNET)
return ERR_PTR(-EINVAL);
return old_net;
}
static inline void net_ns_get_ownership(const struct net *net,
kuid_t *uid, kgid_t *gid)
{
*uid = GLOBAL_ROOT_UID;
*gid = GLOBAL_ROOT_GID;
}
static inline void net_ns_barrier(void) {}
#endif /* CONFIG_NET_NS */
extern struct list_head net_namespace_list;
struct net *get_net_ns_by_pid(pid_t pid);
struct net *get_net_ns_by_fd(int fd);
#ifdef CONFIG_SYSCTL
void ipx_register_sysctl(void);
void ipx_unregister_sysctl(void);
#else
#define ipx_register_sysctl()
#define ipx_unregister_sysctl()
#endif
#ifdef CONFIG_NET_NS
void __put_net(struct net *net);
static inline struct net *get_net(struct net *net)
{
net: Use generic ns_common::count Switch over network namespaces to use the newly introduced common lifetime counter. Network namespaces have an additional counter named "passive". This counter does not guarantee that the network namespace is not already de-initialized and so isn't concerned with the actual lifetime of the network namespace; only the "count" counter is. So the latter is moved into struct ns_common. Currently every namespace type has its own lifetime counter which is stored in the specific namespace struct. The lifetime counters are used identically for all namespaces types. Namespaces may of course have additional unrelated counters and these are not altered. This introduces a common lifetime counter into struct ns_common. The ns_common struct encompasses information that all namespaces share. That should include the lifetime counter since its common for all of them. It also allows us to unify the type of the counters across all namespaces. Most of them use refcount_t but one uses atomic_t and at least one uses kref. Especially the last one doesn't make much sense since it's just a wrapper around refcount_t since 2016 and actually complicates cleanup operations by having to use container_of() to cast the correct namespace struct out of struct ns_common. Having the lifetime counter for the namespaces in one place reduces maintenance cost. Not just because after switching all namespaces over we will have removed more code than we added but also because the logic is more easily understandable and we indicate to the user that the basic lifetime requirements for all namespaces are currently identical. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> [christian.brauner@ubuntu.com: rewrite commit] Link: https://lore.kernel.org/r/159644977635.604812.1319877322927063560.stgit@localhost.localdomain Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-08-19 12:06:36 +00:00
refcount_inc(&net->ns.count);
return net;
}
static inline struct net *maybe_get_net(struct net *net)
{
/* Used when we know struct net exists but we
* aren't guaranteed a previous reference count
* exists. If the reference count is zero this
* function fails and returns NULL.
*/
net: Use generic ns_common::count Switch over network namespaces to use the newly introduced common lifetime counter. Network namespaces have an additional counter named "passive". This counter does not guarantee that the network namespace is not already de-initialized and so isn't concerned with the actual lifetime of the network namespace; only the "count" counter is. So the latter is moved into struct ns_common. Currently every namespace type has its own lifetime counter which is stored in the specific namespace struct. The lifetime counters are used identically for all namespaces types. Namespaces may of course have additional unrelated counters and these are not altered. This introduces a common lifetime counter into struct ns_common. The ns_common struct encompasses information that all namespaces share. That should include the lifetime counter since its common for all of them. It also allows us to unify the type of the counters across all namespaces. Most of them use refcount_t but one uses atomic_t and at least one uses kref. Especially the last one doesn't make much sense since it's just a wrapper around refcount_t since 2016 and actually complicates cleanup operations by having to use container_of() to cast the correct namespace struct out of struct ns_common. Having the lifetime counter for the namespaces in one place reduces maintenance cost. Not just because after switching all namespaces over we will have removed more code than we added but also because the logic is more easily understandable and we indicate to the user that the basic lifetime requirements for all namespaces are currently identical. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> [christian.brauner@ubuntu.com: rewrite commit] Link: https://lore.kernel.org/r/159644977635.604812.1319877322927063560.stgit@localhost.localdomain Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-08-19 12:06:36 +00:00
if (!refcount_inc_not_zero(&net->ns.count))
net = NULL;
return net;
}
static inline void put_net(struct net *net)
{
net: Use generic ns_common::count Switch over network namespaces to use the newly introduced common lifetime counter. Network namespaces have an additional counter named "passive". This counter does not guarantee that the network namespace is not already de-initialized and so isn't concerned with the actual lifetime of the network namespace; only the "count" counter is. So the latter is moved into struct ns_common. Currently every namespace type has its own lifetime counter which is stored in the specific namespace struct. The lifetime counters are used identically for all namespaces types. Namespaces may of course have additional unrelated counters and these are not altered. This introduces a common lifetime counter into struct ns_common. The ns_common struct encompasses information that all namespaces share. That should include the lifetime counter since its common for all of them. It also allows us to unify the type of the counters across all namespaces. Most of them use refcount_t but one uses atomic_t and at least one uses kref. Especially the last one doesn't make much sense since it's just a wrapper around refcount_t since 2016 and actually complicates cleanup operations by having to use container_of() to cast the correct namespace struct out of struct ns_common. Having the lifetime counter for the namespaces in one place reduces maintenance cost. Not just because after switching all namespaces over we will have removed more code than we added but also because the logic is more easily understandable and we indicate to the user that the basic lifetime requirements for all namespaces are currently identical. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> [christian.brauner@ubuntu.com: rewrite commit] Link: https://lore.kernel.org/r/159644977635.604812.1319877322927063560.stgit@localhost.localdomain Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-08-19 12:06:36 +00:00
if (refcount_dec_and_test(&net->ns.count))
__put_net(net);
}
static inline
int net_eq(const struct net *net1, const struct net *net2)
{
return net1 == net2;
}
net: tcp: close sock if net namespace is exiting When a tcp socket is closed, if it detects that its net namespace is exiting, close immediately and do not wait for FIN sequence. For normal sockets, a reference is taken to their net namespace, so it will never exit while the socket is open. However, kernel sockets do not take a reference to their net namespace, so it may begin exiting while the kernel socket is still open. In this case if the kernel socket is a tcp socket, it will stay open trying to complete its close sequence. The sock's dst(s) hold a reference to their interface, which are all transferred to the namespace's loopback interface when the real interfaces are taken down. When the namespace tries to take down its loopback interface, it hangs waiting for all references to the loopback interface to release, which results in messages like: unregister_netdevice: waiting for lo to become free. Usage count = 1 These messages continue until the socket finally times out and closes. Since the net namespace cleanup holds the net_mutex while calling its registered pernet callbacks, any new net namespace initialization is blocked until the current net namespace finishes exiting. After this change, the tcp socket notices the exiting net namespace, and closes immediately, releasing its dst(s) and their reference to the loopback interface, which lets the net namespace continue exiting. Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=97811 Signed-off-by: Dan Streetman <ddstreet@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-18 21:14:26 +00:00
static inline int check_net(const struct net *net)
{
net: Use generic ns_common::count Switch over network namespaces to use the newly introduced common lifetime counter. Network namespaces have an additional counter named "passive". This counter does not guarantee that the network namespace is not already de-initialized and so isn't concerned with the actual lifetime of the network namespace; only the "count" counter is. So the latter is moved into struct ns_common. Currently every namespace type has its own lifetime counter which is stored in the specific namespace struct. The lifetime counters are used identically for all namespaces types. Namespaces may of course have additional unrelated counters and these are not altered. This introduces a common lifetime counter into struct ns_common. The ns_common struct encompasses information that all namespaces share. That should include the lifetime counter since its common for all of them. It also allows us to unify the type of the counters across all namespaces. Most of them use refcount_t but one uses atomic_t and at least one uses kref. Especially the last one doesn't make much sense since it's just a wrapper around refcount_t since 2016 and actually complicates cleanup operations by having to use container_of() to cast the correct namespace struct out of struct ns_common. Having the lifetime counter for the namespaces in one place reduces maintenance cost. Not just because after switching all namespaces over we will have removed more code than we added but also because the logic is more easily understandable and we indicate to the user that the basic lifetime requirements for all namespaces are currently identical. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> [christian.brauner@ubuntu.com: rewrite commit] Link: https://lore.kernel.org/r/159644977635.604812.1319877322927063560.stgit@localhost.localdomain Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-08-19 12:06:36 +00:00
return refcount_read(&net->ns.count) != 0;
net: tcp: close sock if net namespace is exiting When a tcp socket is closed, if it detects that its net namespace is exiting, close immediately and do not wait for FIN sequence. For normal sockets, a reference is taken to their net namespace, so it will never exit while the socket is open. However, kernel sockets do not take a reference to their net namespace, so it may begin exiting while the kernel socket is still open. In this case if the kernel socket is a tcp socket, it will stay open trying to complete its close sequence. The sock's dst(s) hold a reference to their interface, which are all transferred to the namespace's loopback interface when the real interfaces are taken down. When the namespace tries to take down its loopback interface, it hangs waiting for all references to the loopback interface to release, which results in messages like: unregister_netdevice: waiting for lo to become free. Usage count = 1 These messages continue until the socket finally times out and closes. Since the net namespace cleanup holds the net_mutex while calling its registered pernet callbacks, any new net namespace initialization is blocked until the current net namespace finishes exiting. After this change, the tcp socket notices the exiting net namespace, and closes immediately, releasing its dst(s) and their reference to the loopback interface, which lets the net namespace continue exiting. Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=97811 Signed-off-by: Dan Streetman <ddstreet@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-18 21:14:26 +00:00
}
void net_drop_ns(void *);
#else
netns: Don't receive new packets in a dead network namespace. Alexey Dobriyan <adobriyan@gmail.com> writes: > Subject: ICMP sockets destruction vs ICMP packets oops > After icmp_sk_exit() nuked ICMP sockets, we get an interrupt. > icmp_reply() wants ICMP socket. > > Steps to reproduce: > > launch shell in new netns > move real NIC to netns > setup routing > ping -i 0 > exit from shell > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 > IP: [<ffffffff803fce17>] icmp_sk+0x17/0x30 > PGD 17f3cd067 PUD 17f3ce067 PMD 0 > Oops: 0000 [1] PREEMPT SMP DEBUG_PAGEALLOC > CPU 0 > Modules linked in: usblp usbcore > Pid: 0, comm: swapper Not tainted 2.6.26-rc6-netns-ct #4 > RIP: 0010:[<ffffffff803fce17>] [<ffffffff803fce17>] icmp_sk+0x17/0x30 > RSP: 0018:ffffffff8057fc30 EFLAGS: 00010286 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff81017c7db900 > RDX: 0000000000000034 RSI: ffff81017c7db900 RDI: ffff81017dc41800 > RBP: ffffffff8057fc40 R08: 0000000000000001 R09: 000000000000a815 > R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff8057fd28 > R13: ffffffff8057fd00 R14: ffff81017c7db938 R15: ffff81017dc41800 > FS: 0000000000000000(0000) GS:ffffffff80525000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b > CR2: 0000000000000000 CR3: 000000017fcda000 CR4: 00000000000006e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > Process swapper (pid: 0, threadinfo ffffffff8053a000, task ffffffff804fa4a0) > Stack: 0000000000000000 ffff81017c7db900 ffffffff8057fcf0 ffffffff803fcfe4 > ffffffff804faa38 0000000000000246 0000000000005a40 0000000000000246 > 000000000001ffff ffff81017dd68dc0 0000000000005a40 0000000055342436 > Call Trace: > <IRQ> [<ffffffff803fcfe4>] icmp_reply+0x44/0x1e0 > [<ffffffff803d3a0a>] ? ip_route_input+0x23a/0x1360 > [<ffffffff803fd645>] icmp_echo+0x65/0x70 > [<ffffffff803fd300>] icmp_rcv+0x180/0x1b0 > [<ffffffff803d6d84>] ip_local_deliver+0xf4/0x1f0 > [<ffffffff803d71bb>] ip_rcv+0x33b/0x650 > [<ffffffff803bb16a>] netif_receive_skb+0x27a/0x340 > [<ffffffff803be57d>] process_backlog+0x9d/0x100 > [<ffffffff803bdd4d>] net_rx_action+0x18d/0x250 > [<ffffffff80237be5>] __do_softirq+0x75/0x100 > [<ffffffff8020c97c>] call_softirq+0x1c/0x30 > [<ffffffff8020f085>] do_softirq+0x65/0xa0 > [<ffffffff80237af7>] irq_exit+0x97/0xa0 > [<ffffffff8020f198>] do_IRQ+0xa8/0x130 > [<ffffffff80212ee0>] ? mwait_idle+0x0/0x60 > [<ffffffff8020bc46>] ret_from_intr+0x0/0xf > <EOI> [<ffffffff80212f2c>] ? mwait_idle+0x4c/0x60 > [<ffffffff80212f23>] ? mwait_idle+0x43/0x60 > [<ffffffff8020a217>] ? cpu_idle+0x57/0xa0 > [<ffffffff8040f380>] ? rest_init+0x70/0x80 > Code: 10 5b 41 5c 41 5d 41 5e c9 c3 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 53 > 48 83 ec 08 48 8b 9f 78 01 00 00 e8 2b c7 f1 ff 89 c0 <48> 8b 04 c3 48 83 c4 08 > 5b c9 c3 66 66 66 66 66 2e 0f 1f 84 00 > RIP [<ffffffff803fce17>] icmp_sk+0x17/0x30 > RSP <ffffffff8057fc30> > CR2: 0000000000000000 > ---[ end trace ea161157b76b33e8 ]--- > Kernel panic - not syncing: Aiee, killing interrupt handler! Receiving packets while we are cleaning up a network namespace is a racy proposition. It is possible when the packet arrives that we have removed some but not all of the state we need to fully process it. We have the choice of either playing wack-a-mole with the cleanup routines or simply dropping packets when we don't have a network namespace to handle them. Since the check looks inexpensive in netif_receive_skb let's just drop the incoming packets. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-21 05:16:51 +00:00
static inline struct net *get_net(struct net *net)
{
return net;
}
static inline void put_net(struct net *net)
{
}
static inline struct net *maybe_get_net(struct net *net)
{
return net;
}
static inline
int net_eq(const struct net *net1, const struct net *net2)
{
return 1;
}
net: tcp: close sock if net namespace is exiting When a tcp socket is closed, if it detects that its net namespace is exiting, close immediately and do not wait for FIN sequence. For normal sockets, a reference is taken to their net namespace, so it will never exit while the socket is open. However, kernel sockets do not take a reference to their net namespace, so it may begin exiting while the kernel socket is still open. In this case if the kernel socket is a tcp socket, it will stay open trying to complete its close sequence. The sock's dst(s) hold a reference to their interface, which are all transferred to the namespace's loopback interface when the real interfaces are taken down. When the namespace tries to take down its loopback interface, it hangs waiting for all references to the loopback interface to release, which results in messages like: unregister_netdevice: waiting for lo to become free. Usage count = 1 These messages continue until the socket finally times out and closes. Since the net namespace cleanup holds the net_mutex while calling its registered pernet callbacks, any new net namespace initialization is blocked until the current net namespace finishes exiting. After this change, the tcp socket notices the exiting net namespace, and closes immediately, releasing its dst(s) and their reference to the loopback interface, which lets the net namespace continue exiting. Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=97811 Signed-off-by: Dan Streetman <ddstreet@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-18 21:14:26 +00:00
static inline int check_net(const struct net *net)
{
return 1;
}
#define net_drop_ns NULL
#endif
typedef struct {
#ifdef CONFIG_NET_NS
struct net *net;
#endif
} possible_net_t;
static inline void write_pnet(possible_net_t *pnet, struct net *net)
{
#ifdef CONFIG_NET_NS
pnet->net = net;
#endif
}
static inline struct net *read_pnet(const possible_net_t *pnet)
{
#ifdef CONFIG_NET_NS
return pnet->net;
#else
return &init_net;
#endif
}
/* Protected by net_rwsem */
#define for_each_net(VAR) \
list_for_each_entry(VAR, &net_namespace_list, list)
#define for_each_net_continue_reverse(VAR) \
list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list)
#define for_each_net_rcu(VAR) \
list_for_each_entry_rcu(VAR, &net_namespace_list, list)
#ifdef CONFIG_NET_NS
#define __net_init
#define __net_exit
#define __net_initdata
#define __net_initconst
#else
#define __net_init __init
#define __net_exit __ref
#define __net_initdata __initdata
#define __net_initconst __initconst
#endif
int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
int peernet2id(const struct net *net, struct net *peer);
bool peernet_has_id(const struct net *net, struct net *peer);
struct net *get_net_ns_by_id(const struct net *net, int id);
struct pernet_operations {
struct list_head list;
/*
* Below methods are called without any exclusive locks.
* More than one net may be constructed and destructed
* in parallel on several cpus. Every pernet_operations
* have to keep in mind all other pernet_operations and
* to introduce a locking, if they share common resources.
*
* The only time they are called with exclusive lock is
* from register_pernet_subsys(), unregister_pernet_subsys()
* register_pernet_device() and unregister_pernet_device().
*
* Exit methods using blocking RCU primitives, such as
* synchronize_rcu(), should be implemented via exit_batch.
* Then, destruction of a group of net requires single
* synchronize_rcu() related to these pernet_operations,
* instead of separate synchronize_rcu() for every net.
* Please, avoid synchronize_rcu() at all, where it's possible.
*
* Note that a combination of pre_exit() and exit() can
* be used, since a synchronize_rcu() is guaranteed between
* the calls.
*/
int (*init)(struct net *net);
void (*pre_exit)(struct net *net);
void (*exit)(struct net *net);
void (*exit_batch)(struct list_head *net_exit_list);
netns: make struct pernet_operations::id unsigned int Make struct pernet_operations::id unsigned. There are 2 reasons to do so: 1) This field is really an index into an zero based array and thus is unsigned entity. Using negative value is out-of-bound access by definition. 2) On x86_64 unsigned 32-bit data which are mixed with pointers via array indexing or offsets added or subtracted to pointers are preffered to signed 32-bit data. "int" being used as an array index needs to be sign-extended to 64-bit before being used. void f(long *p, int i) { g(p[i]); } roughly translates to movsx rsi, esi mov rdi, [rsi+...] call g MOVSX is 3 byte instruction which isn't necessary if the variable is unsigned because x86_64 is zero extending by default. Now, there is net_generic() function which, you guessed it right, uses "int" as an array index: static inline void *net_generic(const struct net *net, int id) { ... ptr = ng->ptr[id - 1]; ... } And this function is used a lot, so those sign extensions add up. Patch snipes ~1730 bytes on allyesconfig kernel (without all junk messing with code generation): add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) Unfortunately some functions actually grow bigger. This is a semmingly random artefact of code generation with register allocator being used differently. gcc decides that some variable needs to live in new r8+ registers and every access now requires REX prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be used which is longer than [r8] However, overall balance is in negative direction: add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) function old new delta nfsd4_lock 3886 3959 +73 tipc_link_build_proto_msg 1096 1140 +44 mac80211_hwsim_new_radio 2776 2808 +32 tipc_mon_rcv 1032 1058 +26 svcauth_gss_legacy_init 1413 1429 +16 tipc_bcbase_select_primary 379 392 +13 nfsd4_exchange_id 1247 1260 +13 nfsd4_setclientid_confirm 782 793 +11 ... put_client_renew_locked 494 480 -14 ip_set_sockfn_get 730 716 -14 geneve_sock_add 829 813 -16 nfsd4_sequence_done 721 703 -18 nlmclnt_lookup_host 708 686 -22 nfsd4_lockt 1085 1063 -22 nfs_get_client 1077 1050 -27 tcf_bpf_init 1106 1076 -30 nfsd4_encode_fattr 5997 5930 -67 Total: Before=154856051, After=154854321, chg -0.00% Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-17 01:58:21 +00:00
unsigned int *id;
size_t size;
};
/*
* Use these carefully. If you implement a network device and it
* needs per network namespace operations use device pernet operations,
* otherwise use pernet subsys operations.
*
* Network interfaces need to be removed from a dying netns _before_
* subsys notifiers can be called, as most of the network code cleanup
* (which is done from subsys notifiers) runs with the assumption that
* dev_remove_pack has been called so no new packets will arrive during
* and after the cleanup functions have been called. dev_remove_pack
* is not per namespace so instead the guarantee of no more packets
* arriving in a network namespace is provided by ensuring that all
* network devices and all sockets have left the network namespace
* before the cleanup methods are called.
*
* For the longest time the ipv4 icmp code was registered as a pernet
* device which caused kernel oops, and panics during network
* namespace cleanup. So please don't get this wrong.
*/
int register_pernet_subsys(struct pernet_operations *);
void unregister_pernet_subsys(struct pernet_operations *);
int register_pernet_device(struct pernet_operations *);
void unregister_pernet_device(struct pernet_operations *);
struct ctl_table;
struct ctl_table_header;
#ifdef CONFIG_SYSCTL
int net_sysctl_init(void);
struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
struct ctl_table *table);
void unregister_net_sysctl_table(struct ctl_table_header *header);
#else
static inline int net_sysctl_init(void) { return 0; }
static inline struct ctl_table_header *register_net_sysctl(struct net *net,
const char *path, struct ctl_table *table)
{
return NULL;
}
static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
{
}
#endif
static inline int rt_genid_ipv4(const struct net *net)
{
return atomic_read(&net->ipv4.rt_genid);
}
ipv6: Use global sernum for dst validation with nexthop objects Nik reported a bug with pcpu dst cache when nexthop objects are used illustrated by the following: $ ip netns add foo $ ip -netns foo li set lo up $ ip -netns foo addr add 2001:db8:11::1/128 dev lo $ ip netns exec foo sysctl net.ipv6.conf.all.forwarding=1 $ ip li add veth1 type veth peer name veth2 $ ip li set veth1 up $ ip addr add 2001:db8:10::1/64 dev veth1 $ ip li set dev veth2 netns foo $ ip -netns foo li set veth2 up $ ip -netns foo addr add 2001:db8:10::2/64 dev veth2 $ ip -6 nexthop add id 100 via 2001:db8:10::2 dev veth1 $ ip -6 route add 2001:db8:11::1/128 nhid 100 Create a pcpu entry on cpu 0: $ taskset -a -c 0 ip -6 route get 2001:db8:11::1 Re-add the route entry: $ ip -6 ro del 2001:db8:11::1 $ ip -6 route add 2001:db8:11::1/128 nhid 100 Route get on cpu 0 returns the stale pcpu: $ taskset -a -c 0 ip -6 route get 2001:db8:11::1 RTNETLINK answers: Network is unreachable While cpu 1 works: $ taskset -a -c 1 ip -6 route get 2001:db8:11::1 2001:db8:11::1 from :: via 2001:db8:10::2 dev veth1 src 2001:db8:10::1 metric 1024 pref medium Conversion of FIB entries to work with external nexthop objects missed an important difference between IPv4 and IPv6 - how dst entries are invalidated when the FIB changes. IPv4 has a per-network namespace generation id (rt_genid) that is bumped on changes to the FIB. Checking if a dst_entry is still valid means comparing rt_genid in the rtable to the current value of rt_genid for the namespace. IPv6 also has a per network namespace counter, fib6_sernum, but the count is saved per fib6_node. With the per-node counter only dst_entries based on fib entries under the node are invalidated when changes are made to the routes - limiting the scope of invalidations. IPv6 uses a reference in the rt6_info, 'from', to track the corresponding fib entry used to create the dst_entry. When validating a dst_entry, the 'from' is used to backtrack to the fib6_node and check the sernum of it to the cookie passed to the dst_check operation. With the inline format (nexthop definition inline with the fib6_info), dst_entries cached in the fib6_nh have a 1:1 correlation between fib entries, nexthop data and dst_entries. With external nexthops, IPv6 looks more like IPv4 which means multiple fib entries across disparate fib6_nodes can all reference the same fib6_nh. That means validation of dst_entries based on external nexthops needs to use the IPv4 format - the per-network namespace counter. Add sernum to rt6_info and set it when creating a pcpu dst entry. Update rt6_get_cookie to return sernum if it is set and update dst_check for IPv6 to look for sernum set and based the check on it if so. Finally, rt6_get_pcpu_route needs to validate the cached entry before returning a pcpu entry (similar to the rt_cache_valid calls in __mkroute_input and __mkroute_output for IPv4). This problem only affects routes using the new, external nexthops. Thanks to the kbuild test robot for catching the IS_ENABLED needed around rt_genid_ipv6 before I sent this out. Fixes: 5b98324ebe29 ("ipv6: Allow routes to use nexthop objects") Reported-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David Ahern <dsahern@kernel.org> Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Tested-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-01 14:53:08 +00:00
#if IS_ENABLED(CONFIG_IPV6)
static inline int rt_genid_ipv6(const struct net *net)
{
return atomic_read(&net->ipv6.fib6_sernum);
}
#endif
static inline void rt_genid_bump_ipv4(struct net *net)
{
atomic_inc(&net->ipv4.rt_genid);
}
extern void (*__fib6_flush_trees)(struct net *net);
static inline void rt_genid_bump_ipv6(struct net *net)
{
if (__fib6_flush_trees)
__fib6_flush_trees(net);
}
#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
static inline struct netns_ieee802154_lowpan *
net_ieee802154_lowpan(struct net *net)
{
return &net->ieee802154_lowpan;
}
#endif
/* For callers who don't really care about whether it's IPv4 or IPv6 */
static inline void rt_genid_bump_all(struct net *net)
{
rt_genid_bump_ipv4(net);
rt_genid_bump_ipv6(net);
}
static inline int fnhe_genid(const struct net *net)
{
return atomic_read(&net->fnhe_genid);
}
static inline void fnhe_genid_bump(struct net *net)
{
atomic_inc(&net->fnhe_genid);
}
#endif /* __NET_NET_NAMESPACE_H */