Re: BUG: sleeping function called from invalid context in lock_sock_nested (2)

[Guenter Roeck]

On 2/22/20 7:08 AM, syzbot wrote:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    0a44cac8 Merge tag 'dma-mapping-5.6' of git://git.infradea..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=152eba29e00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=a61f2164c515c07f
> dashboard link: https://syzkaller.appspot.com/bug?extid=a5df189917e79d5e59c9
> compiler:       clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=117a0931e00000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17d8c109e00000
>
> The bug was bisected to:
>
> commit 5ac6badc5aa057ceb1d50c93326a81db6e89ad2f
> Author: Daniel Mack <daniel@xxxxxxxxxx>
> Date:   Thu Jul 11 12:45:03 2019 +0000
>
>      device-tree: bindinds: add NXP PCT2075 as compatible device to LM75

Guess syzbot's bisect mechanism needs a bit of work.

Guenter

> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=15924629e00000
> final crash:    https://syzkaller.appspot.com/x/report.txt?x=17924629e00000
> console output: https://syzkaller.appspot.com/x/log.txt?x=13924629e00000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+a5df189917e79d5e59c9@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: 5ac6badc5aa0 ("device-tree: bindinds: add NXP PCT2075 as compatible device to LM75")
>
> BUG: sleeping function called from invalid context at net/core/sock.c:2935
> in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2687, name: kworker/1:3
> INFO: lockdep is turned off.
> Preemption disabled at:
> [<ffffffff867b39c7>] sock_hash_free+0xd7/0x460 net/core/sock_map.c:869
> CPU: 1 PID: 2687 Comm: kworker/1:3 Not tainted 5.6.0-rc2-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> Workqueue: events bpf_map_free_deferred
> Call Trace:
>   __dump_stack lib/dump_stack.c:77 [inline]
>   dump_stack+0x1fb/0x318 lib/dump_stack.c:118
>   ___might_sleep+0x449/0x5e0 kernel/sched/core.c:6798
>   __might_sleep+0x8f/0x100 kernel/sched/core.c:6751
>   lock_sock_nested+0x36/0x120 net/core/sock.c:2935
>   lock_sock include/net/sock.h:1516 [inline]
>   sock_hash_free+0x200/0x460 net/core/sock_map.c:872
>   bpf_map_free_deferred+0xb2/0x110 kernel/bpf/syscall.c:474
>   process_one_work+0x7f5/0x10f0 kernel/workqueue.c:2264
>   worker_thread+0xbbc/0x1630 kernel/workqueue.c:2410
>   kthread+0x332/0x350 kernel/kthread.c:255
>   ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
>
>
> ---
> This bug is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxxx
>
> syzbot will keep track of this bug report. See:
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> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
> syzbot can test patches for this bug, for details see:
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