kernel.git/net/core/sock.c, branch linux-6.15.y

net: dst: add four helpers to annotate data-races around dst->dev

2025-08-15T10:16:27Z

[ Upstream commit 88fe14253e181878c2ddb51a298ae8c468a63010 ] dst->dev is read locklessly in many contexts, and written in dst_dev_put(). Fixing all the races is going to need many changes. We probably will have to add full RCU protection. Add three helpers to ease this painful process. static inline struct net_device *dst_dev(const struct dst_entry *dst) { return READ_ONCE(dst->dev); } static inline struct net_device *skb_dst_dev(const struct sk_buff *skb) { return dst_dev(skb_dst(skb)); } static inline struct net *skb_dst_dev_net(const struct sk_buff *skb) { return dev_net(skb_dst_dev(skb)); } static inline struct net *skb_dst_dev_net_rcu(const struct sk_buff *skb) { return dev_net_rcu(skb_dst_dev(skb)); } Fixes: 4a6ce2b6f2ec ("net: introduce a new function dst_dev_put()") Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250630121934.3399505-7-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

sock: Correct error checking condition for (assign|release)_proto_idx()

2025-06-27T10:13:28Z

[ Upstream commit faeefc173be40512341b102cf1568aa0b6571acd ] (assign|release)_proto_idx() wrongly check find_first_zero_bit() failure by condition '(prot->inuse_idx == PROTO_INUSE_NR - 1)' obviously. Fix by correcting the condition to '(prot->inuse_idx == PROTO_INUSE_NR)' Signed-off-by: Zijun Hu Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250410-fix_net-v2-1-d69e7c5739a4@quicinc.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

Fix sock_exceed_buf_limit not being triggered in __sk_mem_raise_allocated

2025-06-19T13:40:35Z

[ Upstream commit 8542d6fac25c03b4bf36b2d762cfe60fda8491bb ] When a process under memory pressure is not part of any cgroup and the charged flag is false, trace_sock_exceed_buf_limit was not called as expected. This regression was introduced by commit 2def8ff3fdb6 ("sock: Code cleanup on __sk_mem_raise_allocated()"). The fix changes the default value of charged to true while preserving existing logic. Fixes: 2def8ff3fdb6 ("sock: Code cleanup on __sk_mem_raise_allocated()") Signed-off-by: Abel Wu Signed-off-by: Tengteng Yang Link: https://patch.msgid.link/20250527030419.67693-1-yangtengteng@bytedance.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

Merge tag 'net-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2025-04-10T15:52:18Z

Pull networking fixes from Paolo Abeni: "Including fixes from netfilter. Current release - regressions: - core: hold instance lock during NETDEV_CHANGE - rtnetlink: fix bad unlock balance in do_setlink() - ipv6: - fix null-ptr-deref in addrconf_add_ifaddr() - align behavior across nexthops during path selection Previous releases - regressions: - sctp: prevent transport UaF in sendmsg - mptcp: only inc MPJoinAckHMacFailure for HMAC failures Previous releases - always broken: - sched: - make ->qlen_notify() idempotent - ensure sufficient space when sending filter netlink notifications - sch_sfq: really don't allow 1 packet limit - netfilter: fix incorrect avx2 match of 5th field octet - tls: explicitly disallow disconnect - eth: octeontx2-pf: fix VF root node parent queue priority" * tag 'net-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (38 commits) ethtool: cmis_cdb: Fix incorrect read / write length extension selftests: netfilter: add test case for recent mismatch bug nft_set_pipapo: fix incorrect avx2 match of 5th field octet net: ppp: Add bound checking for skb data on ppp_sync_txmung net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod. ipv6: Align behavior across nexthops during path selection net: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY net: phy: move phy_link_change() prior to mdio_bus_phy_may_suspend() selftests/tc-testing: sfq: check that a derived limit of 1 is rejected net_sched: sch_sfq: move the limit validation net_sched: sch_sfq: use a temporary work area for validating configuration net: libwx: handle page_pool_dev_alloc_pages error selftests: mptcp: validate MPJoin HMacFailure counters mptcp: only inc MPJoinAckHMacFailure for HMAC failures rtnetlink: Fix bad unlock balance in do_setlink(). net: ethtool: Don't call .cleanup_data when prepare_data fails tc: Ensure we have enough buffer space when sending filter netlink notifications net: libwx: Fix the wrong Rx descriptor field octeontx2-pf: qos: fix VF root node parent queue index selftests: tls: check that disconnect does nothing ...

net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod.

2025-04-10T02:11:55Z

When I ran the repro [0] and waited a few seconds, I observed two LOCKDEP splats: a warning immediately followed by a null-ptr-deref. [1] Reproduction Steps: 1) Mount CIFS 2) Add an iptables rule to drop incoming FIN packets for CIFS 3) Unmount CIFS 4) Unload the CIFS module 5) Remove the iptables rule At step 3), the CIFS module calls sock_release() for the underlying TCP socket, and it returns quickly. However, the socket remains in FIN_WAIT_1 because incoming FIN packets are dropped. At this point, the module's refcnt is 0 while the socket is still alive, so the following rmmod command succeeds. # ss -tan State Recv-Q Send-Q Local Address:Port Peer Address:Port FIN-WAIT-1 0 477 10.0.2.15:51062 10.0.0.137:445 # lsmod | grep cifs cifs 1159168 0 This highlights a discrepancy between the lifetime of the CIFS module and the underlying TCP socket. Even after CIFS calls sock_release() and it returns, the TCP socket does not die immediately in order to close the connection gracefully. While this is generally fine, it causes an issue with LOCKDEP because CIFS assigns a different lock class to the TCP socket's sk->sk_lock using sock_lock_init_class_and_name(). Once an incoming packet is processed for the socket or a timer fires, sk->sk_lock is acquired. Then, LOCKDEP checks the lock context in check_wait_context(), where hlock_class() is called to retrieve the lock class. However, since the module has already been unloaded, hlock_class() logs a warning and returns NULL, triggering the null-ptr-deref. If LOCKDEP is enabled, we must ensure that a module calling sock_lock_init_class_and_name() (CIFS, NFS, etc) cannot be unloaded while such a socket is still alive to prevent this issue. Let's hold the module reference in sock_lock_init_class_and_name() and release it when the socket is freed in sk_prot_free(). Note that sock_lock_init() clears sk->sk_owner for svc_create_socket() that calls sock_lock_init_class_and_name() for a listening socket, which clones a socket by sk_clone_lock() without GFP_ZERO. [0]: CIFS_SERVER="10.0.0.137" CIFS_PATH="//${CIFS_SERVER}/Users/Administrator/Desktop/CIFS_TEST" DEV="enp0s3" CRED="/root/WindowsCredential.txt" MNT=$(mktemp -d /tmp/XXXXXX) mount -t cifs ${CIFS_PATH} ${MNT} -o vers=3.0,credentials=${CRED},cache=none,echo_interval=1 iptables -A INPUT -s ${CIFS_SERVER} -j DROP for i in $(seq 10); do umount ${MNT} rmmod cifs sleep 1 done rm -r ${MNT} iptables -D INPUT -s ${CIFS_SERVER} -j DROP [1]: DEBUG_LOCKS_WARN_ON(1) WARNING: CPU: 10 PID: 0 at kernel/locking/lockdep.c:234 hlock_class (kernel/locking/lockdep.c:234 kernel/locking/lockdep.c:223) Modules linked in: cifs_arc4 nls_ucs2_utils cifs_md4 [last unloaded: cifs] CPU: 10 UID: 0 PID: 0 Comm: swapper/10 Not tainted 6.14.0 #36 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:hlock_class (kernel/locking/lockdep.c:234 kernel/locking/lockdep.c:223) ... Call Trace: __lock_acquire (kernel/locking/lockdep.c:4853 kernel/locking/lockdep.c:5178) lock_acquire (kernel/locking/lockdep.c:469 kernel/locking/lockdep.c:5853 kernel/locking/lockdep.c:5816) _raw_spin_lock_nested (kernel/locking/spinlock.c:379) tcp_v4_rcv (./include/linux/skbuff.h:1678 ./include/net/tcp.h:2547 net/ipv4/tcp_ipv4.c:2350) ... BUG: kernel NULL pointer dereference, address: 00000000000000c4 PF: supervisor read access in kernel mode PF: error_code(0x0000) - not-present page PGD 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 10 UID: 0 PID: 0 Comm: swapper/10 Tainted: G W 6.14.0 #36 Tainted: [W]=WARN Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:__lock_acquire (kernel/locking/lockdep.c:4852 kernel/locking/lockdep.c:5178) Code: 15 41 09 c7 41 8b 44 24 20 25 ff 1f 00 00 41 09 c7 8b 84 24 a0 00 00 00 45 89 7c 24 20 41 89 44 24 24 e8 e1 bc ff ff 4c 89 e7 <44> 0f b6 b8 c4 00 00 00 e8 d1 bc ff ff 0f b6 80 c5 00 00 00 88 44 RSP: 0018:ffa0000000468a10 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ff1100010091cc38 RCX: 0000000000000027 RDX: ff1100081f09ca48 RSI: 0000000000000001 RDI: ff1100010091cc88 RBP: ff1100010091c200 R08: ff1100083fe6e228 R09: 00000000ffffbfff R10: ff1100081eca0000 R11: ff1100083fe10dc0 R12: ff1100010091cc88 R13: 0000000000000001 R14: 0000000000000000 R15: 00000000000424b1 FS: 0000000000000000(0000) GS:ff1100081f080000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000c4 CR3: 0000000002c4a003 CR4: 0000000000771ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: lock_acquire (kernel/locking/lockdep.c:469 kernel/locking/lockdep.c:5853 kernel/locking/lockdep.c:5816) _raw_spin_lock_nested (kernel/locking/spinlock.c:379) tcp_v4_rcv (./include/linux/skbuff.h:1678 ./include/net/tcp.h:2547 net/ipv4/tcp_ipv4.c:2350) ip_protocol_deliver_rcu (net/ipv4/ip_input.c:205 (discriminator 1)) ip_local_deliver_finish (./include/linux/rcupdate.h:878 net/ipv4/ip_input.c:234) ip_sublist_rcv_finish (net/ipv4/ip_input.c:576) ip_list_rcv_finish (net/ipv4/ip_input.c:628) ip_list_rcv (net/ipv4/ip_input.c:670) __netif_receive_skb_list_core (net/core/dev.c:5939 net/core/dev.c:5986) netif_receive_skb_list_internal (net/core/dev.c:6040 net/core/dev.c:6129) napi_complete_done (./include/linux/list.h:37 ./include/net/gro.h:519 ./include/net/gro.h:514 net/core/dev.c:6496) e1000_clean (drivers/net/ethernet/intel/e1000/e1000_main.c:3815) __napi_poll.constprop.0 (net/core/dev.c:7191) net_rx_action (net/core/dev.c:7262 net/core/dev.c:7382) handle_softirqs (kernel/softirq.c:561) __irq_exit_rcu (kernel/softirq.c:596 kernel/softirq.c:435 kernel/softirq.c:662) irq_exit_rcu (kernel/softirq.c:680) common_interrupt (arch/x86/kernel/irq.c:280 (discriminator 14)) asm_common_interrupt (./arch/x86/include/asm/idtentry.h:693) RIP: 0010:default_idle (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:92 arch/x86/kernel/process.c:744) Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d c3 2b 15 00 fb f4 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 RSP: 0018:ffa00000000ffee8 EFLAGS: 00000202 RAX: 000000000000640b RBX: ff1100010091c200 RCX: 0000000000061aa4 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff812f30c5 RBP: 000000000000000a R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ? do_idle (kernel/sched/idle.c:186 kernel/sched/idle.c:325) default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) do_idle (kernel/sched/idle.c:186 kernel/sched/idle.c:325) cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:315) common_startup_64 (arch/x86/kernel/head_64.S:421) Modules linked in: cifs_arc4 nls_ucs2_utils cifs_md4 [last unloaded: cifs] CR2: 00000000000000c4 Fixes: ed07536ed673 ("[PATCH] lockdep: annotate nfs/nfsd in-kernel sockets") Signed-off-by: Kuniyuki Iwashima Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250407163313.22682-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12Z

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar

tcp: cache RTAX_QUICKACK metric in a hot cache line

2025-03-18T12:44:59Z

tcp_in_quickack_mode() is called from input path for small packets. It calls __sk_dst_get() which reads sk->sk_dst_cache which has been put in sock_read_tx group (for good reasons). Then dst_metric(dst, RTAX_QUICKACK) also needs extra cache line misses. Cache RTAX_QUICKACK in icsk->icsk_ack.dst_quick_ack to no longer pull these cache lines for the cases a delayed ACK is scheduled. After this patch TCP receive path does not longer access sock_read_tx group. Signed-off-by: Eric Dumazet Reviewed-by: Jason Xing Reviewed-by: Neal Cardwell Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250312083907.1931644-1-edumazet@google.com Signed-off-by: Paolo Abeni

sock: add sock_kmemdup helper

2025-03-04T01:16:34Z

This patch adds the sock version of kmemdup() helper, named sock_kmemdup(), to duplicate the input "src" memory block using the socket's option memory buffer. Signed-off-by: Geliang Tang Reviewed-by: Kuniyuki Iwashima Acked-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/f828077394c7d1f3560123497348b438c875b510.1740735165.git.tanggeliang@kylinos.cn Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2025-02-27T18:20:58Z

Cross-merge networking fixes after downstream PR (net-6.14-rc5). Conflicts: drivers/net/ethernet/cadence/macb_main.c fa52f15c745c ("net: cadence: macb: Synchronize stats calculations") 75696dd0fd72 ("net: cadence: macb: Convert to get_stats64") https://lore.kernel.org/20250224125848.68ee63e5@canb.auug.org.au Adjacent changes: drivers/net/ethernet/intel/ice/ice_sriov.c 79990cf5e7ad ("ice: Fix deinitializing VF in error path") a203163274a4 ("ice: simplify VF MSI-X managing") net/ipv4/tcp.c 18912c520674 ("tcp: devmem: don't write truncated dmabuf CMSGs to userspace") 297d389e9e5b ("net: prefix devmem specific helpers") net/mptcp/subflow.c 8668860b0ad3 ("mptcp: reset when MPTCP opts are dropped after join") c3349a22c200 ("mptcp: consolidate subflow cleanup") Signed-off-by: Jakub Kicinski

net: better track kernel sockets lifetime

2025-02-22T00:00:58Z

While kernel sockets are dismantled during pernet_operations->exit(), their freeing can be delayed by any tx packets still held in qdisc or device queues, due to skb_set_owner_w() prior calls. This then trigger the following warning from ref_tracker_dir_exit() [1] To fix this, make sure that kernel sockets own a reference on net->passive. Add sk_net_refcnt_upgrade() helper, used whenever a kernel socket is converted to a refcounted one. [1] [ 136.263918][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at [ 136.263918][ T35] sk_alloc+0x2b3/0x370 [ 136.263918][ T35] inet6_create+0x6ce/0x10f0 [ 136.263918][ T35] __sock_create+0x4c0/0xa30 [ 136.263918][ T35] inet_ctl_sock_create+0xc2/0x250 [ 136.263918][ T35] igmp6_net_init+0x39/0x390 [ 136.263918][ T35] ops_init+0x31e/0x590 [ 136.263918][ T35] setup_net+0x287/0x9e0 [ 136.263918][ T35] copy_net_ns+0x33f/0x570 [ 136.263918][ T35] create_new_namespaces+0x425/0x7b0 [ 136.263918][ T35] unshare_nsproxy_namespaces+0x124/0x180 [ 136.263918][ T35] ksys_unshare+0x57d/0xa70 [ 136.263918][ T35] __x64_sys_unshare+0x38/0x40 [ 136.263918][ T35] do_syscall_64+0xf3/0x230 [ 136.263918][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 136.263918][ T35] [ 136.343488][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at [ 136.343488][ T35] sk_alloc+0x2b3/0x370 [ 136.343488][ T35] inet6_create+0x6ce/0x10f0 [ 136.343488][ T35] __sock_create+0x4c0/0xa30 [ 136.343488][ T35] inet_ctl_sock_create+0xc2/0x250 [ 136.343488][ T35] ndisc_net_init+0xa7/0x2b0 [ 136.343488][ T35] ops_init+0x31e/0x590 [ 136.343488][ T35] setup_net+0x287/0x9e0 [ 136.343488][ T35] copy_net_ns+0x33f/0x570 [ 136.343488][ T35] create_new_namespaces+0x425/0x7b0 [ 136.343488][ T35] unshare_nsproxy_namespaces+0x124/0x180 [ 136.343488][ T35] ksys_unshare+0x57d/0xa70 [ 136.343488][ T35] __x64_sys_unshare+0x38/0x40 [ 136.343488][ T35] do_syscall_64+0xf3/0x230 [ 136.343488][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: 0cafd77dcd03 ("net: add a refcount tracker for kernel sockets") Reported-by: syzbot+30a19e01a97420719891@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/67b72aeb.050a0220.14d86d.0283.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250220131854.4048077-1-edumazet@google.com Signed-off-by: Jakub Kicinski