mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-08-31 14:04:27 -04:00
b8a7826e4b
As demonstrated by syzbot, WARN_ON_ONCE() in tcf_classify() can be easily triggered by fault injection. [0] We should not use WARN_ON_ONCE() for the simple -ENOMEM case. Also, we provide SKB_DROP_REASON_NOMEM for the same error. Let's remove WARN_ON_ONCE() there. [0]: FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 UID: 0 PID: 31392 Comm: syz.8.7081 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: <TASK> dump_stack_lvl+0x189/0x250 should_fail_ex+0x414/0x560 should_failslab+0xa8/0x100 kmem_cache_alloc_noprof+0x74/0x6e0 skb_ext_add+0x148/0x8f0 tcf_classify+0xeba/0x1140 multiq_enqueue+0xfd/0x4c0 net/sched/sch_multiq.c:66 ... WARNING: CPU: 0 PID: 31392 at net/sched/cls_api.c:1869 tcf_classify+0xfd7/0x1140 Modules linked in: CPU: 0 UID: 0 PID: 31392 Comm: syz.8.7081 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:tcf_classify+0xfd7/0x1140 Code: e8 03 42 0f b6 04 30 84 c0 0f 85 41 01 00 00 66 41 89 1f eb 05 e8 89 26 75 f8 bb ff ff ff ff e9 04 f9 ff ff e8 7a 26 75 f8 90 <0f> 0b 90 49 83 c5 44 4c 89 eb 49 c1 ed 03 43 0f b6 44 35 00 84 c0 RSP: 0018:ffffc9000b7671f0 EFLAGS: 00010293 RAX: ffffffff894addf6 RBX: 0000000000000002 RCX: ffff888025029e40 RDX: 0000000000000000 RSI: ffffffff8bbf05c0 RDI: ffffffff8bbf0580 RBP: 0000000000000000 R08: 00000000ffffffff R09: 1ffffffff1c0bfd6 R10: dffffc0000000000 R11: fffffbfff1c0bfd7 R12: ffff88805a90de5c R13: ffff88805a90ddc0 R14: dffffc0000000000 R15: ffffc9000b7672c0 FS: 00007f20739f66c0(0000) GS:ffff88812613e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2d2a80 CR3: 0000000024e36000 CR4: 00000000003526f0 Call Trace: <TASK> multiq_classify net/sched/sch_multiq.c:39 [inline] multiq_enqueue+0xfd/0x4c0 net/sched/sch_multiq.c:66 dev_qdisc_enqueue+0x4e/0x260 net/core/dev.c:4118 __dev_xmit_skb net/core/dev.c:4214 [inline] __dev_queue_xmit+0xe83/0x3b50 net/core/dev.c:4729 packet_snd net/packet/af_packet.c:3076 [inline] packet_sendmsg+0x3e33/0x5080 net/packet/af_packet.c:3108 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x505/0x830 net/socket.c:2630 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 __sys_sendmsg net/socket.c:2716 [inline] __do_sys_sendmsg net/socket.c:2721 [inline] __se_sys_sendmsg net/socket.c:2719 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2719 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f207578efc9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f20739f6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f20759e5fa0 RCX: 00007f207578efc9 RDX: 0000000000000004 RSI: 00002000000000c0 RDI: 0000000000000008 RBP: 00007f20739f6090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f20759e6038 R14: 00007f20759e5fa0 R15: 00007f2075b0fa28 </TASK> Reported-by: syzbot+87e1289a044fcd0c5f62@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/69003e33.050a0220.32483.00e8.GAE@google.com/ Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20251028035859.2067690-1-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.