Re: WARNING: ODEBUG bug in del_timer (3)

[Jakub Kicinski <jakub.kicinski@netronome.com>]

CCing John, looks like John's upcoming fix may address this:

bpf: sockmap, only stop/flush strp if it was enabled at some point

On Tue, 07 May 2019 14:06:06 -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    71ae5fc8 Merge tag 'linux-kselftest-5.2-rc1' of git://git...
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=136c06f0a00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=511168bc7720867
> dashboard link: https://syzkaller.appspot.com/bug?extid=13d91ed9bbcd7dc13230
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17128012a00000
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+13d91ed9bbcd7dc13230@syzkaller.appspotmail.com
> 
> ------------[ cut here ]------------
> ODEBUG: assert_init not available (active state 0) object type: timer_list  
> hint:           (null)
> WARNING: CPU: 1 PID: 22 at lib/debugobjects.c:325  
> debug_print_object+0x16a/0x250 lib/debugobjects.c:325
> Kernel panic - not syncing: panic_on_warn set ...
> CPU: 1 PID: 22 Comm: kworker/1:1 Not tainted 5.1.0+ #1
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
> Google 01/01/2011
> Workqueue: events sk_psock_destroy_deferred
> Call Trace:
>   __dump_stack lib/dump_stack.c:77 [inline]
>   dump_stack+0x172/0x1f0 lib/dump_stack.c:113
>   panic+0x2cb/0x65c kernel/panic.c:214
>   __warn.cold+0x20/0x45 kernel/panic.c:566
>   report_bug+0x263/0x2b0 lib/bug.c:186
>   fixup_bug arch/x86/kernel/traps.c:179 [inline]
>   fixup_bug arch/x86/kernel/traps.c:174 [inline]
>   do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
>   do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291
>   invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:972
> RIP: 0010:debug_print_object+0x16a/0x250 lib/debugobjects.c:325
> Code: dd 60 f4 a1 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48  
> 8b 14 dd 60 f4 a1 87 48 c7 c7 00 ea a1 87 e8 44 02 12 fe <0f> 0b 83 05 31  
> 10 2d 06 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3
> RSP: 0018:ffff8880a9a3f970 EFLAGS: 00010086
> RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffffffff815aec76 RDI: ffffed1015347f20
> RBP: ffff8880a9a3f9b0 R08: ffff8880a9a2a5c0 R09: ffffed1015d240f1
> R10: ffffed1015d240f0 R11: ffff8880ae920787 R12: 0000000000000001
> R13: ffffffff889ac720 R14: ffffffff81605b60 R15: ffff8880990fdba8
>   debug_object_assert_init lib/debugobjects.c:694 [inline]
>   debug_object_assert_init+0x23d/0x2f0 lib/debugobjects.c:665
>   debug_timer_assert_init kernel/time/timer.c:725 [inline]
>   debug_assert_init kernel/time/timer.c:770 [inline]
>   del_timer+0x7c/0x120 kernel/time/timer.c:1192
>   try_to_grab_pending+0x2d7/0x710 kernel/workqueue.c:1249
>   __cancel_work_timer+0xc4/0x520 kernel/workqueue.c:3079
>   cancel_delayed_work_sync+0x1b/0x20 kernel/workqueue.c:3252
>   strp_done+0x5d/0xf0 net/strparser/strparser.c:526
>   sk_psock_destroy_deferred+0x3a/0x6c0 net/core/skmsg.c:558
>   process_one_work+0x98e/0x1790 kernel/workqueue.c:2263
>   worker_thread+0x98/0xe40 kernel/workqueue.c:2409
>   kthread+0x357/0x430 kernel/kthread.c:253
>   ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
> Kernel Offset: disabled
> Rebooting in 86400 seconds..
> 
> 
> ---
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