linux.git/net/core, branch master Linux kernel source tree Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2026-04-03T01:59:56+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-04-03T01:59:56+00:00 7b9e74c5a49e1331e03c8ae5f981067da4f33328 Pull bpf fixes from Alexei Starovoitov: - Fix register equivalence for pointers to packet (Alexei Starovoitov) - Fix incorrect pruning due to atomic fetch precision tracking (Daniel Borkmann) - Fix grace period wait for bpf_link-ed tracepoints (Kumar Kartikeya Dwivedi) - Fix use-after-free of sockmap's sk->sk_socket (Kuniyuki Iwashima) - Reject direct access to nullable PTR_TO_BUF pointers (Qi Tang) - Reject sleepable kprobe_multi programs at attach time (Varun R Mallya) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: selftests/bpf: Add more precision tracking tests for atomics bpf: Fix incorrect pruning due to atomic fetch precision tracking bpf: Reject sleepable kprobe_multi programs at attach time bpf: reject direct access to nullable PTR_TO_BUF pointers bpf: sockmap: Fix use-after-free of sk->sk_socket in sk_psock_verdict_data_ready(). bpf: Fix grace period wait for tracepoint bpf_link bpf: Fix regsafe() for pointers to packet 
Pull bpf fixes from Alexei Starovoitov:

 - Fix register equivalence for pointers to packet (Alexei Starovoitov)

 - Fix incorrect pruning due to atomic fetch precision tracking (Daniel
   Borkmann)

 - Fix grace period wait for bpf_link-ed tracepoints (Kumar Kartikeya
   Dwivedi)

 - Fix use-after-free of sockmap's sk->sk_socket (Kuniyuki Iwashima)

 - Reject direct access to nullable PTR_TO_BUF pointers (Qi Tang)

 - Reject sleepable kprobe_multi programs at attach time (Varun R
   Mallya)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: Add more precision tracking tests for atomics
  bpf: Fix incorrect pruning due to atomic fetch precision tracking
  bpf: Reject sleepable kprobe_multi programs at attach time
  bpf: reject direct access to nullable PTR_TO_BUF pointers
  bpf: sockmap: Fix use-after-free of sk->sk_socket in sk_psock_verdict_data_ready().
  bpf: Fix grace period wait for tracepoint bpf_link
  bpf: Fix regsafe() for pointers to packet
bpf: sockmap: Fix use-after-free of sk->sk_socket in sk_psock_verdict_data_ready(). 2026-04-02T01:54:04+00:00 Kuniyuki Iwashima kuniyu@google.com 2026-04-01T00:54:15+00:00 ad8391d37f334ee73ba91926f8b4e4cf6d31ea04 syzbot reported use-after-free of AF_UNIX socket's sk->sk_socket in sk_psock_verdict_data_ready(). [0] In unix_stream_sendmsg(), the peer socket's ->sk_data_ready() is called after dropping its unix_state_lock(). Although the sender socket holds the peer's refcount, it does not prevent the peer's sock_orphan(), and the peer's sk_socket might be freed after one RCU grace period. Let's fetch the peer's sk->sk_socket and sk->sk_socket->ops under RCU in sk_psock_verdict_data_ready(). [0]: BUG: KASAN: slab-use-after-free in sk_psock_verdict_data_ready+0xec/0x590 net/core/skmsg.c:1278 Read of size 8 at addr ffff8880594da860 by task syz.4.1842/11013 CPU: 1 UID: 0 PID: 11013 Comm: syz.4.1842 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: <TASK> dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 sk_psock_verdict_data_ready+0xec/0x590 net/core/skmsg.c:1278 unix_stream_sendmsg+0x8a3/0xe80 net/unix/af_unix.c:2482 sock_sendmsg_nosec net/socket.c:721 [inline] __sock_sendmsg net/socket.c:736 [inline] ____sys_sendmsg+0x972/0x9f0 net/socket.c:2585 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2639 __sys_sendmsg net/socket.c:2671 [inline] __do_sys_sendmsg net/socket.c:2676 [inline] __se_sys_sendmsg net/socket.c:2674 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2674 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7facf899c819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007facf9827028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007facf8c15fa0 RCX: 00007facf899c819 RDX: 0000000000000000 RSI: 0000200000000500 RDI: 0000000000000004 RBP: 00007facf8a32c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007facf8c16038 R14: 00007facf8c15fa0 R15: 00007ffd41b01c78 </TASK> Allocated by task 11013: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4538 [inline] slab_alloc_node mm/slub.c:4866 [inline] kmem_cache_alloc_lru_noprof+0x2b8/0x640 mm/slub.c:4885 sock_alloc_inode+0x28/0xc0 net/socket.c:316 alloc_inode+0x6a/0x1b0 fs/inode.c:347 new_inode_pseudo include/linux/fs.h:3003 [inline] sock_alloc net/socket.c:631 [inline] __sock_create+0x12d/0x9d0 net/socket.c:1562 sock_create net/socket.c:1656 [inline] __sys_socketpair+0x1c4/0x560 net/socket.c:1803 __do_sys_socketpair net/socket.c:1856 [inline] __se_sys_socketpair net/socket.c:1853 [inline] __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1853 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 15: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2685 [inline] slab_free mm/slub.c:6165 [inline] kmem_cache_free+0x187/0x630 mm/slub.c:6295 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1063 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Fixes: c63829182c37 ("af_unix: Implement ->psock_update_sk_prot()") Closes: https://lore.kernel.org/bpf/69cc6b9f.a70a0220.128fd0.004b.GAE@google.com/ Reported-by: syzbot+2184232f07e3677fbaef@syzkaller.appspotmail.com Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://patch.msgid.link/20260401005418.2452999-1-kuniyu@google.com 
syzbot reported use-after-free of AF_UNIX socket's sk->sk_socket
in sk_psock_verdict_data_ready(). [0]

In unix_stream_sendmsg(), the peer socket's ->sk_data_ready() is
called after dropping its unix_state_lock().

Although the sender socket holds the peer's refcount, it does not
prevent the peer's sock_orphan(), and the peer's sk_socket might
be freed after one RCU grace period.

Let's fetch the peer's sk->sk_socket and sk->sk_socket->ops under
RCU in sk_psock_verdict_data_ready().

[0]:
BUG: KASAN: slab-use-after-free in sk_psock_verdict_data_ready+0xec/0x590 net/core/skmsg.c:1278
Read of size 8 at addr ffff8880594da860 by task syz.4.1842/11013

CPU: 1 UID: 0 PID: 11013 Comm: syz.4.1842 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xba/0x230 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 sk_psock_verdict_data_ready+0xec/0x590 net/core/skmsg.c:1278
 unix_stream_sendmsg+0x8a3/0xe80 net/unix/af_unix.c:2482
 sock_sendmsg_nosec net/socket.c:721 [inline]
 __sock_sendmsg net/socket.c:736 [inline]
 ____sys_sendmsg+0x972/0x9f0 net/socket.c:2585
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2639
 __sys_sendmsg net/socket.c:2671 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7facf899c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007facf9827028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007facf8c15fa0 RCX: 00007facf899c819
RDX: 0000000000000000 RSI: 0000200000000500 RDI: 0000000000000004
RBP: 00007facf8a32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007facf8c16038 R14: 00007facf8c15fa0 R15: 00007ffd41b01c78
 </TASK>

Allocated by task 11013:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4538 [inline]
 slab_alloc_node mm/slub.c:4866 [inline]
 kmem_cache_alloc_lru_noprof+0x2b8/0x640 mm/slub.c:4885
 sock_alloc_inode+0x28/0xc0 net/socket.c:316
 alloc_inode+0x6a/0x1b0 fs/inode.c:347
 new_inode_pseudo include/linux/fs.h:3003 [inline]
 sock_alloc net/socket.c:631 [inline]
 __sock_create+0x12d/0x9d0 net/socket.c:1562
 sock_create net/socket.c:1656 [inline]
 __sys_socketpair+0x1c4/0x560 net/socket.c:1803
 __do_sys_socketpair net/socket.c:1856 [inline]
 __se_sys_socketpair net/socket.c:1853 [inline]
 __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1853
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 15:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2685 [inline]
 slab_free mm/slub.c:6165 [inline]
 kmem_cache_free+0x187/0x630 mm/slub.c:6295
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869
 handle_softirqs+0x22a/0x870 kernel/softirq.c:622
 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1063
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Fixes: c63829182c37 ("af_unix: Implement ->psock_update_sk_prot()")
Closes: https://lore.kernel.org/bpf/69cc6b9f.a70a0220.128fd0.004b.GAE@google.com/
Reported-by: syzbot+2184232f07e3677fbaef@syzkaller.appspotmail.com
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://patch.msgid.link/20260401005418.2452999-1-kuniyu@google.com
net: use skb_header_pointer() for TCPv4 GSO frag_off check 2026-03-31T00:35:21+00:00 Guoyu Su yss2813483011xxl@gmail.com 2026-03-27T15:35:07+00:00 ddc748a391dd8642ba6b2e4fe22e7f2ddf84b7f0 Syzbot reported a KMSAN uninit-value warning in gso_features_check() called from netif_skb_features() [1]. gso_features_check() reads iph->frag_off to decide whether to clear mangleid_features. Accessing the IPv4 header via ip_hdr()/inner_ip_hdr() can rely on skb header offsets that are not always safe for direct dereference on packets injected from PF_PACKET paths. Use skb_header_pointer() for the TCPv4 frag_off check so the header read is robust whether data is already linear or needs copying. [1] https://syzkaller.appspot.com/bug?extid=1543a7d954d9c6d00407 Link: https://lore.kernel.org/netdev/willemdebruijn.kernel.1a9f35039caab@gmail.com/ Fixes: cbc53e08a793 ("GSO: Add GSO type for fixed IPv4 ID") Reported-by: syzbot+1543a7d954d9c6d00407@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=1543a7d954d9c6d00407 Tested-by: syzbot+1543a7d954d9c6d00407@syzkaller.appspotmail.com Signed-off-by: Guoyu Su <yss2813483011xxl@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260327153507.39742-1-yss2813483011xxl@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Syzbot reported a KMSAN uninit-value warning in gso_features_check()
called from netif_skb_features() [1].

gso_features_check() reads iph->frag_off to decide whether to clear
mangleid_features. Accessing the IPv4 header via ip_hdr()/inner_ip_hdr()
can rely on skb header offsets that are not always safe for direct
dereference on packets injected from PF_PACKET paths.

Use skb_header_pointer() for the TCPv4 frag_off check so the header read
is robust whether data is already linear or needs copying.

[1] https://syzkaller.appspot.com/bug?extid=1543a7d954d9c6d00407

Link: https://lore.kernel.org/netdev/willemdebruijn.kernel.1a9f35039caab@gmail.com/
Fixes: cbc53e08a793 ("GSO: Add GSO type for fixed IPv4 ID")
Reported-by: syzbot+1543a7d954d9c6d00407@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1543a7d954d9c6d00407
Tested-by: syzbot+1543a7d954d9c6d00407@syzkaller.appspotmail.com
Signed-off-by: Guoyu Su <yss2813483011xxl@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260327153507.39742-1-yss2813483011xxl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rtnetlink: fix leak of SRCU struct in rtnl_link_register 2026-03-25T03:56:02+00:00 Sabrina Dubroca sd@queasysnail.net 2026-03-23T15:19:43+00:00 09474055f2619be9445ba4245e4013741ed01a5e Commit 6b57ff21a310 ("rtnetlink: Protect link_ops by mutex.") swapped the EEXIST check with the init_srcu_struct, but didn't add cleanup of the SRCU struct we just allocated in case of error. Fixes: 6b57ff21a310 ("rtnetlink: Protect link_ops by mutex.") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/e77fe499f9a58c547b33b5212b3596dad417cec6.1774025341.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Commit 6b57ff21a310 ("rtnetlink: Protect link_ops by mutex.") swapped
the EEXIST check with the init_srcu_struct, but didn't add cleanup of
the SRCU struct we just allocated in case of error.

Fixes: 6b57ff21a310 ("rtnetlink: Protect link_ops by mutex.")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/e77fe499f9a58c547b33b5212b3596dad417cec6.1774025341.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: correctly handle tunneled traffic on IPV6_CSUM GSO fallback 2026-03-24T11:35:19+00:00 Willem de Bruijn willemb@google.com 2026-03-20T19:01:46+00:00 c4336a07eb6b2526dc2b62928b5104b41a7f81f5 NETIF_F_IPV6_CSUM only advertises support for checksum offload of packets without IPv6 extension headers. Packets with extension headers must fall back onto software checksumming. Since TSO depends on checksum offload, those must revert to GSO. The below commit introduces that fallback. It always checks network header length. For tunneled packets, the inner header length must be checked instead. Extend the check accordingly. A special case is tunneled packets without inner IP protocol. Such as RFC 6951 SCTP in UDP. Those are not standard IPv6 followed by transport header either, so also must revert to the software GSO path. Cc: stable@vger.kernel.org Fixes: 864e3396976e ("net: gso: Forbid IPv6 TSO with extensions on devices with only IPV6_CSUM") Reported-by: Tangxin Xie <xietangxin@yeah.net> Closes: https://lore.kernel.org/netdev/0414e7e2-9a1c-4d7c-a99d-b9039cf68f40@yeah.net/ Suggested-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260320190148.2409107-1-willemdebruijn.kernel@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
NETIF_F_IPV6_CSUM only advertises support for checksum offload of
packets without IPv6 extension headers. Packets with extension
headers must fall back onto software checksumming. Since TSO
depends on checksum offload, those must revert to GSO.

The below commit introduces that fallback. It always checks
network header length. For tunneled packets, the inner header length
must be checked instead. Extend the check accordingly.

A special case is tunneled packets without inner IP protocol. Such as
RFC 6951 SCTP in UDP. Those are not standard IPv6 followed by
transport header either, so also must revert to the software GSO path.

Cc: stable@vger.kernel.org
Fixes: 864e3396976e ("net: gso: Forbid IPv6 TSO with extensions on devices with only IPV6_CSUM")
Reported-by: Tangxin Xie <xietangxin@yeah.net>
Closes: https://lore.kernel.org/netdev/0414e7e2-9a1c-4d7c-a99d-b9039cf68f40@yeah.net/
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260320190148.2409107-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
rtnetlink: count IFLA_INFO_SLAVE_KIND in if_nlmsg_size 2026-03-21T02:05:12+00:00 Sabrina Dubroca sd@queasysnail.net 2026-03-19T23:02:53+00:00 ee00a12593ffb69db4dd1a1c00ecb0253376874a rtnl_link_get_slave_info_data_size counts IFLA_INFO_SLAVE_DATA, but rtnl_link_slave_info_fill adds both IFLA_INFO_SLAVE_DATA and IFLA_INFO_SLAVE_KIND. Fixes: ba7d49b1f0f8 ("rtnetlink: provide api for getting and setting slave info") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Link: https://patch.msgid.link/049843b532e23cde7ddba263c0bbe35ba6f0d26d.1773919462.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
rtnl_link_get_slave_info_data_size counts IFLA_INFO_SLAVE_DATA, but
rtnl_link_slave_info_fill adds both IFLA_INFO_SLAVE_DATA and
IFLA_INFO_SLAVE_KIND.

Fixes: ba7d49b1f0f8 ("rtnetlink: provide api for getting and setting slave info")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/049843b532e23cde7ddba263c0bbe35ba6f0d26d.1773919462.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rtnetlink: count IFLA_PARENT_DEV_{NAME,BUS_NAME} in if_nlmsg_size 2026-03-21T02:05:11+00:00 Sabrina Dubroca sd@queasysnail.net 2026-03-19T23:02:52+00:00 52501989c76206462d9b11a8485beef40ef41821 Commit 00e77ed8e64d ("rtnetlink: add IFLA_PARENT_[DEV|DEV_BUS]_NAME") added those attributes to rtnl_fill_ifinfo, but forgot to extend if_nlmsg_size. Fixes: 00e77ed8e64d ("rtnetlink: add IFLA_PARENT_[DEV|DEV_BUS]_NAME") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Link: https://patch.msgid.link/0b849da95562af45487080528d60f578636aba5c.1773919462.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Commit 00e77ed8e64d ("rtnetlink: add IFLA_PARENT_[DEV|DEV_BUS]_NAME")
added those attributes to rtnl_fill_ifinfo, but forgot to extend
if_nlmsg_size.

Fixes: 00e77ed8e64d ("rtnetlink: add IFLA_PARENT_[DEV|DEV_BUS]_NAME")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/0b849da95562af45487080528d60f578636aba5c.1773919462.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
neighbour: restore protocol != 0 check in pneigh update 2026-03-12T02:04:55+00:00 Sabrina Dubroca sd@queasysnail.net 2026-03-10T21:59:16+00:00 cbada1048847a348797aec63a1d8056621cbe653 Prior to commit dc2a27e524ac ("neighbour: Update pneigh_entry in pneigh_create()."), a pneigh's protocol was updated only when the value of the NDA_PROTOCOL attribute was non-0. While moving the code, that check was removed. This is a small change of user-visible behavior, and inconsistent with the (non-proxy) neighbour behavior. Fixes: dc2a27e524ac ("neighbour: Update pneigh_entry in pneigh_create().") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/38c61de1bb032871a886aff9b9b52fe1cdd4cada.1772894876.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Prior to commit dc2a27e524ac ("neighbour: Update pneigh_entry in
pneigh_create()."), a pneigh's protocol was updated only when the
value of the NDA_PROTOCOL attribute was non-0. While moving the code,
that check was removed. This is a small change of user-visible
behavior, and inconsistent with the (non-proxy) neighbour behavior.

Fixes: dc2a27e524ac ("neighbour: Update pneigh_entry in pneigh_create().")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/38c61de1bb032871a886aff9b9b52fe1cdd4cada.1772894876.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
bpf: bpf_out_neigh_v6: Fix nd_tbl NULL dereference when IPv6 is disabled 2026-03-12T00:53:38+00:00 Ricardo B. Marlière rbm@suse.com 2026-03-07T20:50:56+00:00 d56b5d163458c45ab8fa1f00bd875af01b3ce28c When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never initialized because inet6_init() exits before ndisc_init() is called which initializes it. If bpf_redirect_neigh() is called with explicit AF_INET6 nexthop parameters, __bpf_redirect_neigh_v6() can skip the IPv6 FIB lookup and call bpf_out_neigh_v6() directly. bpf_out_neigh_v6() then calls ip_neigh_gw6(), which uses ipv6_stub->nd_tbl. BUG: kernel NULL pointer dereference, address: 0000000000000248 Oops: Oops: 0000 [#1] SMP NOPTI RIP: 0010:skb_do_redirect+0x44f/0xf40 Call Trace: <TASK> ? srso_alias_return_thunk+0x5/0xfbef5 ? __tcf_classify.constprop.0+0x83/0x160 ? srso_alias_return_thunk+0x5/0xfbef5 ? tcf_classify+0x2b/0x50 ? srso_alias_return_thunk+0x5/0xfbef5 ? tc_run+0xb8/0x120 ? srso_alias_return_thunk+0x5/0xfbef5 __dev_queue_xmit+0x6fa/0x1000 ? srso_alias_return_thunk+0x5/0xfbef5 packet_sendmsg+0x10da/0x1700 ? srso_alias_return_thunk+0x5/0xfbef5 __sys_sendto+0x1f3/0x220 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x101/0xf80 ? exc_page_fault+0x6e/0x170 ? srso_alias_return_thunk+0x5/0xfbef5 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Fix this by adding an early check in bpf_out_neigh_v6(). If IPv6 is disabled, drop the packet before neighbor lookup. Suggested-by: Fernando Fernandez Mancera <fmancera@suse.de> Fixes: ba452c9e996d ("bpf: Fix bpf_redirect_neigh helper api to support supplying nexthop") Signed-off-by: Ricardo B. Marlière <rbm@suse.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://patch.msgid.link/20260307-net-nd_tbl_fixes-v4-4-e2677e85628c@suse.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
initialized because inet6_init() exits before ndisc_init() is called which
initializes it. If bpf_redirect_neigh() is called with explicit AF_INET6
nexthop parameters, __bpf_redirect_neigh_v6() can skip the IPv6 FIB lookup
and call bpf_out_neigh_v6() directly. bpf_out_neigh_v6() then calls
ip_neigh_gw6(), which uses ipv6_stub->nd_tbl.

 BUG: kernel NULL pointer dereference, address: 0000000000000248
 Oops: Oops: 0000 [#1] SMP NOPTI
 RIP: 0010:skb_do_redirect+0x44f/0xf40
 Call Trace:
  <TASK>
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? __tcf_classify.constprop.0+0x83/0x160
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? tcf_classify+0x2b/0x50
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? tc_run+0xb8/0x120
  ? srso_alias_return_thunk+0x5/0xfbef5
  __dev_queue_xmit+0x6fa/0x1000
  ? srso_alias_return_thunk+0x5/0xfbef5
  packet_sendmsg+0x10da/0x1700
  ? srso_alias_return_thunk+0x5/0xfbef5
  __sys_sendto+0x1f3/0x220
  __x64_sys_sendto+0x24/0x30
  do_syscall_64+0x101/0xf80
  ? exc_page_fault+0x6e/0x170
  ? srso_alias_return_thunk+0x5/0xfbef5
  entry_SYSCALL_64_after_hwframe+0x77/0x7f
  </TASK>

Fix this by adding an early check in bpf_out_neigh_v6(). If IPv6 is
disabled, drop the packet before neighbor lookup.

Suggested-by: Fernando Fernandez Mancera <fmancera@suse.de>
Fixes: ba452c9e996d ("bpf: Fix bpf_redirect_neigh helper api to support supplying nexthop")
Signed-off-by: Ricardo B. Marlière <rbm@suse.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/20260307-net-nd_tbl_fixes-v4-4-e2677e85628c@suse.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
bpf: bpf_out_neigh_v4: Fix nd_tbl NULL dereference when IPv6 is disabled 2026-03-12T00:53:38+00:00 Ricardo B. Marlière rbm@suse.com 2026-03-07T20:50:55+00:00 dcb4e2231469523d20cf0a2477d68245795c205d When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never initialized because inet6_init() exits before ndisc_init() is called which initializes it. If bpf_redirect_neigh() is called from tc with an explicit nexthop of nh_family == AF_INET6, bpf_out_neigh_v4() takes the AF_INET6 branch and calls ip_neigh_gw6(), which relies on ipv6_stub->nd_tbl. BUG: kernel NULL pointer dereference, address: 0000000000000248 Oops: Oops: 0000 [#1] SMP NOPTI RIP: 0010:skb_do_redirect+0xb93/0xf00 Call Trace: <TASK> ? srso_alias_return_thunk+0x5/0xfbef5 ? __tcf_classify.constprop.0+0x83/0x160 ? srso_alias_return_thunk+0x5/0xfbef5 ? tcf_classify+0x2b/0x50 ? srso_alias_return_thunk+0x5/0xfbef5 ? tc_run+0xb8/0x120 ? srso_alias_return_thunk+0x5/0xfbef5 __dev_queue_xmit+0x6fa/0x1000 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? alloc_skb_with_frags+0x58/0x200 packet_sendmsg+0x10da/0x1700 ? srso_alias_return_thunk+0x5/0xfbef5 __sys_sendto+0x1f3/0x220 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x101/0xf80 ? exc_page_fault+0x6e/0x170 ? srso_alias_return_thunk+0x5/0xfbef5 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Fix this by adding an early check in the AF_INET6 branch of bpf_out_neigh_v4(). If IPv6 is disabled, unlock RCU and drop the packet. Suggested-by: Fernando Fernandez Mancera <fmancera@suse.de> Fixes: ba452c9e996d ("bpf: Fix bpf_redirect_neigh helper api to support supplying nexthop") Signed-off-by: Ricardo B. Marlière <rbm@suse.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://patch.msgid.link/20260307-net-nd_tbl_fixes-v4-3-e2677e85628c@suse.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
initialized because inet6_init() exits before ndisc_init() is called which
initializes it. If bpf_redirect_neigh() is called from tc with an explicit
nexthop of nh_family == AF_INET6, bpf_out_neigh_v4() takes the AF_INET6
branch and calls ip_neigh_gw6(), which relies on ipv6_stub->nd_tbl.

 BUG: kernel NULL pointer dereference, address: 0000000000000248
 Oops: Oops: 0000 [#1] SMP NOPTI
 RIP: 0010:skb_do_redirect+0xb93/0xf00
 Call Trace:
  <TASK>
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? __tcf_classify.constprop.0+0x83/0x160
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? tcf_classify+0x2b/0x50
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? tc_run+0xb8/0x120
  ? srso_alias_return_thunk+0x5/0xfbef5
  __dev_queue_xmit+0x6fa/0x1000
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? srso_alias_return_thunk+0x5/0xfbef5
  ? alloc_skb_with_frags+0x58/0x200
  packet_sendmsg+0x10da/0x1700
  ? srso_alias_return_thunk+0x5/0xfbef5
  __sys_sendto+0x1f3/0x220
  __x64_sys_sendto+0x24/0x30
  do_syscall_64+0x101/0xf80
  ? exc_page_fault+0x6e/0x170
  ? srso_alias_return_thunk+0x5/0xfbef5
  entry_SYSCALL_64_after_hwframe+0x77/0x7f
  </TASK>

Fix this by adding an early check in the AF_INET6 branch of
bpf_out_neigh_v4(). If IPv6 is disabled, unlock RCU and drop the packet.

Suggested-by: Fernando Fernandez Mancera <fmancera@suse.de>
Fixes: ba452c9e996d ("bpf: Fix bpf_redirect_neigh helper api to support supplying nexthop")
Signed-off-by: Ricardo B. Marlière <rbm@suse.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/20260307-net-nd_tbl_fixes-v4-3-e2677e85628c@suse.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>