Hello,
syzbot found the following issue on:
HEAD commit: 6b8d4927540e Add linux-next specific files for 20220104
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=159d88e3b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=45c9bbbf2ae8e3d3
dashboard link: https://syzkaller.appspot.com/bug?extid=5426c7ed6868c705ca14
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=117be65db00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15a75c8db00000
The issue was bisected to:
commit e4b8954074f6d0db01c8c97d338a67f9389c042f
Author: Eric Dumazet <[email protected]>
Date: Tue Dec 7 01:30:37 2021 +0000
netlink: add net device refcount tracker to struct ethnl_req_info
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12bca4e3b00000
final oops: https://syzkaller.appspot.com/x/report.txt?x=11bca4e3b00000
console output: https://syzkaller.appspot.com/x/log.txt?x=16bca4e3b00000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]
Fixes: e4b8954074f6 ("netlink: add net device refcount tracker to struct ethnl_req_info")
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3604 at kernel/sched/wait.c:245 __wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:246
Modules linked in:
CPU: 0 PID: 3604 Comm: syz-executor714 Not tainted 5.16.0-rc8-next-20220104-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:245
Code: f3 ff ff 48 8d 6b 40 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 80 3c 02 00 75 11 48 8b 43 40 48 39 c5 75 03 5b 5d c3 <0f> 0b 5b 5d c3 48 89 ef e8 13 d8 69 00 eb e5 cc 48 c1 e7 06 48 63
RSP: 0018:ffffc90001aaf9f8 EFLAGS: 00010083
RAX: ffff88801cd623f0 RBX: ffff88801bec8048 RCX: 0000000000000000
RDX: 1ffff110037d9011 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffff88801bec8088 R08: 0000000000000000 R09: ffff88801bec804b
R10: ffffed10037d9009 R11: 0000000000000000 R12: ffff88801bec8040
R13: ffff88801e029d40 R14: dffffc0000000000 R15: ffff88807eb50000
FS: 00005555573ad300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200000c0 CR3: 000000001e5e4000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
wake_up_pollfree include/linux/wait.h:271 [inline]
signalfd_cleanup+0x42/0x60 fs/signalfd.c:38
__cleanup_sighand kernel/fork.c:1596 [inline]
__cleanup_sighand+0x72/0xb0 kernel/fork.c:1593
__exit_signal kernel/exit.c:159 [inline]
release_task+0xc02/0x17e0 kernel/exit.c:200
wait_task_zombie kernel/exit.c:1117 [inline]
wait_consider_task+0x2fa6/0x3b80 kernel/exit.c:1344
do_wait_thread kernel/exit.c:1407 [inline]
do_wait+0x6ca/0xce0 kernel/exit.c:1524
kernel_wait4+0x14c/0x260 kernel/exit.c:1687
__do_sys_wait4+0x13f/0x150 kernel/exit.c:1715
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7facd6682386
Code: 0f 1f 40 00 31 c9 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 49 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 90 48 83 ec 28 89 54 24 14 48 89 74 24
RSP: 002b:00007ffdb91adef8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 000000000000c646 RCX: 00007facd6682386
RDX: 0000000040000001 RSI: 00007ffdb91adf14 RDI: 00000000ffffffff
RBP: 0000000000000f17 R08: 0000000000000032 R09: 00007ffdb91ec080
R10: 0000000000000000 R11: 0000000000000246 R12: 431bde82d7b634db
R13: 00007ffdb91adf14 R14: 0000000000000000 R15: 0000000000000000
</TASK>
---
This report 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 [email protected].
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches
On Wed, Jan 5, 2022 at 7:37 AM syzbot
<[email protected]> wrote:
>
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 6b8d4927540e Add linux-next specific files for 20220104
> git tree: linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=159d88e3b00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=45c9bbbf2ae8e3d3
> dashboard link: https://syzkaller.appspot.com/bug?extid=5426c7ed6868c705ca14
> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=117be65db00000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15a75c8db00000
>
C repro looks legit, point to an io_uring issue.
> The issue was bisected to:
Please ignore the bisection.
>
> commit e4b8954074f6d0db01c8c97d338a67f9389c042f
> Author: Eric Dumazet <[email protected]>
> Date: Tue Dec 7 01:30:37 2021 +0000
>
> netlink: add net device refcount tracker to struct ethnl_req_info
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12bca4e3b00000
> final oops: https://syzkaller.appspot.com/x/report.txt?x=11bca4e3b00000
> console output: https://syzkaller.appspot.com/x/log.txt?x=16bca4e3b00000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: [email protected]
> Fixes: e4b8954074f6 ("netlink: add net device refcount tracker to struct ethnl_req_info")
>
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 3604 at kernel/sched/wait.c:245 __wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:246
> Modules linked in:
> CPU: 0 PID: 3604 Comm: syz-executor714 Not tainted 5.16.0-rc8-next-20220104-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> RIP: 0010:__wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:245
> Code: f3 ff ff 48 8d 6b 40 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 80 3c 02 00 75 11 48 8b 43 40 48 39 c5 75 03 5b 5d c3 <0f> 0b 5b 5d c3 48 89 ef e8 13 d8 69 00 eb e5 cc 48 c1 e7 06 48 63
> RSP: 0018:ffffc90001aaf9f8 EFLAGS: 00010083
> RAX: ffff88801cd623f0 RBX: ffff88801bec8048 RCX: 0000000000000000
> RDX: 1ffff110037d9011 RSI: 0000000000000004 RDI: 0000000000000001
> RBP: ffff88801bec8088 R08: 0000000000000000 R09: ffff88801bec804b
> R10: ffffed10037d9009 R11: 0000000000000000 R12: ffff88801bec8040
> R13: ffff88801e029d40 R14: dffffc0000000000 R15: ffff88807eb50000
> FS: 00005555573ad300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00000000200000c0 CR3: 000000001e5e4000 CR4: 00000000003506f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <TASK>
> wake_up_pollfree include/linux/wait.h:271 [inline]
> signalfd_cleanup+0x42/0x60 fs/signalfd.c:38
> __cleanup_sighand kernel/fork.c:1596 [inline]
> __cleanup_sighand+0x72/0xb0 kernel/fork.c:1593
> __exit_signal kernel/exit.c:159 [inline]
> release_task+0xc02/0x17e0 kernel/exit.c:200
> wait_task_zombie kernel/exit.c:1117 [inline]
> wait_consider_task+0x2fa6/0x3b80 kernel/exit.c:1344
> do_wait_thread kernel/exit.c:1407 [inline]
> do_wait+0x6ca/0xce0 kernel/exit.c:1524
> kernel_wait4+0x14c/0x260 kernel/exit.c:1687
> __do_sys_wait4+0x13f/0x150 kernel/exit.c:1715
> do_syscall_x64 arch/x86/entry/common.c:50 [inline]
> do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
> entry_SYSCALL_64_after_hwframe+0x44/0xae
> RIP: 0033:0x7facd6682386
> Code: 0f 1f 40 00 31 c9 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 49 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 90 48 83 ec 28 89 54 24 14 48 89 74 24
> RSP: 002b:00007ffdb91adef8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
> RAX: ffffffffffffffda RBX: 000000000000c646 RCX: 00007facd6682386
> RDX: 0000000040000001 RSI: 00007ffdb91adf14 RDI: 00000000ffffffff
> RBP: 0000000000000f17 R08: 0000000000000032 R09: 00007ffdb91ec080
> R10: 0000000000000000 R11: 0000000000000246 R12: 431bde82d7b634db
> R13: 00007ffdb91adf14 R14: 0000000000000000 R15: 0000000000000000
> </TASK>
>
>
> ---
> This report 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 [email protected].
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
> syzbot can test patches for this issue, for details see:
> https://goo.gl/tpsmEJ#testing-patches
[+io_uring list and maintainers]
This appears to be the known bug in io_uring where it doesn't POLLFREE
notifications. See previous discussion:
https://lore.kernel.org/all/[email protected]/
On Wed, Jan 05, 2022 at 07:42:10AM -0800, 'Eric Dumazet' via syzkaller-bugs wrote:
> On Wed, Jan 5, 2022 at 7:37 AM syzbot
> <[email protected]> wrote:
> >
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > HEAD commit: 6b8d4927540e Add linux-next specific files for 20220104
> > git tree: linux-next
> > console output: https://syzkaller.appspot.com/x/log.txt?x=159d88e3b00000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=45c9bbbf2ae8e3d3
> > dashboard link: https://syzkaller.appspot.com/bug?extid=5426c7ed6868c705ca14
> > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=117be65db00000
> > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15a75c8db00000
> >
>
> C repro looks legit, point to an io_uring issue.
>
> > The issue was bisected to:
>
> Please ignore the bisection.
>
> >
> > commit e4b8954074f6d0db01c8c97d338a67f9389c042f
> > Author: Eric Dumazet <[email protected]>
> > Date: Tue Dec 7 01:30:37 2021 +0000
> >
> > netlink: add net device refcount tracker to struct ethnl_req_info
> >
> > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12bca4e3b00000
> > final oops: https://syzkaller.appspot.com/x/report.txt?x=11bca4e3b00000
> > console output: https://syzkaller.appspot.com/x/log.txt?x=16bca4e3b00000
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: [email protected]
> > Fixes: e4b8954074f6 ("netlink: add net device refcount tracker to struct ethnl_req_info")
> >
> > ------------[ cut here ]------------
> > WARNING: CPU: 0 PID: 3604 at kernel/sched/wait.c:245 __wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:246
> > Modules linked in:
> > CPU: 0 PID: 3604 Comm: syz-executor714 Not tainted 5.16.0-rc8-next-20220104-syzkaller #0
> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> > RIP: 0010:__wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:245
> > Code: f3 ff ff 48 8d 6b 40 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 80 3c 02 00 75 11 48 8b 43 40 48 39 c5 75 03 5b 5d c3 <0f> 0b 5b 5d c3 48 89 ef e8 13 d8 69 00 eb e5 cc 48 c1 e7 06 48 63
> > RSP: 0018:ffffc90001aaf9f8 EFLAGS: 00010083
> > RAX: ffff88801cd623f0 RBX: ffff88801bec8048 RCX: 0000000000000000
> > RDX: 1ffff110037d9011 RSI: 0000000000000004 RDI: 0000000000000001
> > RBP: ffff88801bec8088 R08: 0000000000000000 R09: ffff88801bec804b
> > R10: ffffed10037d9009 R11: 0000000000000000 R12: ffff88801bec8040
> > R13: ffff88801e029d40 R14: dffffc0000000000 R15: ffff88807eb50000
> > FS: 00005555573ad300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
> > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: 00000000200000c0 CR3: 000000001e5e4000 CR4: 00000000003506f0
> > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> > Call Trace:
> > <TASK>
> > wake_up_pollfree include/linux/wait.h:271 [inline]
> > signalfd_cleanup+0x42/0x60 fs/signalfd.c:38
> > __cleanup_sighand kernel/fork.c:1596 [inline]
> > __cleanup_sighand+0x72/0xb0 kernel/fork.c:1593
> > __exit_signal kernel/exit.c:159 [inline]
> > release_task+0xc02/0x17e0 kernel/exit.c:200
> > wait_task_zombie kernel/exit.c:1117 [inline]
> > wait_consider_task+0x2fa6/0x3b80 kernel/exit.c:1344
> > do_wait_thread kernel/exit.c:1407 [inline]
> > do_wait+0x6ca/0xce0 kernel/exit.c:1524
> > kernel_wait4+0x14c/0x260 kernel/exit.c:1687
> > __do_sys_wait4+0x13f/0x150 kernel/exit.c:1715
> > do_syscall_x64 arch/x86/entry/common.c:50 [inline]
> > do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
> > entry_SYSCALL_64_after_hwframe+0x44/0xae
> > RIP: 0033:0x7facd6682386
> > Code: 0f 1f 40 00 31 c9 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 49 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 90 48 83 ec 28 89 54 24 14 48 89 74 24
> > RSP: 002b:00007ffdb91adef8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
> > RAX: ffffffffffffffda RBX: 000000000000c646 RCX: 00007facd6682386
> > RDX: 0000000040000001 RSI: 00007ffdb91adf14 RDI: 00000000ffffffff
> > RBP: 0000000000000f17 R08: 0000000000000032 R09: 00007ffdb91ec080
> > R10: 0000000000000000 R11: 0000000000000246 R12: 431bde82d7b634db
> > R13: 00007ffdb91adf14 R14: 0000000000000000 R15: 0000000000000000
> > </TASK>
> >
> >
> > ---
> > This report 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 [email protected].
> >
> > syzbot will keep track of this issue. See:
> > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> > For information about bisection process see: https://goo.gl/tpsmEJ#bisection
> > syzbot can test patches for this issue, for details see:
> > https://goo.gl/tpsmEJ#testing-patches
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/CANn89iK3tP3rANSWM7_%3DimMeMcUknT0U2GyfA9W4v12ad6_PkQ%40mail.gmail.com.
On 1/5/22 15:52, Eric Biggers wrote:
> [+io_uring list and maintainers]
>
> This appears to be the known bug in io_uring where it doesn't POLLFREE
> notifications. See previous discussion:
> https://lore.kernel.org/all/[email protected]/
We've got some fixing and groundwork done, but not POLLFREE yet.
Great to have a repro, thanks
> On Wed, Jan 05, 2022 at 07:42:10AM -0800, 'Eric Dumazet' via syzkaller-bugs wrote:
>> On Wed, Jan 5, 2022 at 7:37 AM syzbot
>> <[email protected]> wrote:
>>>
>>> Hello,
>>>
>>> syzbot found the following issue on:
>>>
>>> HEAD commit: 6b8d4927540e Add linux-next specific files for 20220104
>>> git tree: linux-next
>>> console output: https://syzkaller.appspot.com/x/log.txt?x=159d88e3b00000
>>> kernel config: https://syzkaller.appspot.com/x/.config?x=45c9bbbf2ae8e3d3
>>> dashboard link: https://syzkaller.appspot.com/bug?extid=5426c7ed6868c705ca14
>>> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
>>> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=117be65db00000
>>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15a75c8db00000
>>>
>>
>> C repro looks legit, point to an io_uring issue.
>>
>>> The issue was bisected to:
>>
>> Please ignore the bisection.
>>
>>>
>>> commit e4b8954074f6d0db01c8c97d338a67f9389c042f
>>> Author: Eric Dumazet <[email protected]>
>>> Date: Tue Dec 7 01:30:37 2021 +0000
>>>
>>> netlink: add net device refcount tracker to struct ethnl_req_info
>>>
>>> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12bca4e3b00000
>>> final oops: https://syzkaller.appspot.com/x/report.txt?x=11bca4e3b00000
>>> console output: https://syzkaller.appspot.com/x/log.txt?x=16bca4e3b00000
>>>
>>> IMPORTANT: if you fix the issue, please add the following tag to the commit:
>>> Reported-by: [email protected]
>>> Fixes: e4b8954074f6 ("netlink: add net device refcount tracker to struct ethnl_req_info")
>>>
>>> ------------[ cut here ]------------
>>> WARNING: CPU: 0 PID: 3604 at kernel/sched/wait.c:245 __wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:246
>>> Modules linked in:
>>> CPU: 0 PID: 3604 Comm: syz-executor714 Not tainted 5.16.0-rc8-next-20220104-syzkaller #0
>>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
>>> RIP: 0010:__wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:245
>>> Code: f3 ff ff 48 8d 6b 40 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 80 3c 02 00 75 11 48 8b 43 40 48 39 c5 75 03 5b 5d c3 <0f> 0b 5b 5d c3 48 89 ef e8 13 d8 69 00 eb e5 cc 48 c1 e7 06 48 63
>>> RSP: 0018:ffffc90001aaf9f8 EFLAGS: 00010083
>>> RAX: ffff88801cd623f0 RBX: ffff88801bec8048 RCX: 0000000000000000
>>> RDX: 1ffff110037d9011 RSI: 0000000000000004 RDI: 0000000000000001
>>> RBP: ffff88801bec8088 R08: 0000000000000000 R09: ffff88801bec804b
>>> R10: ffffed10037d9009 R11: 0000000000000000 R12: ffff88801bec8040
>>> R13: ffff88801e029d40 R14: dffffc0000000000 R15: ffff88807eb50000
>>> FS: 00005555573ad300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
>>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>>> CR2: 00000000200000c0 CR3: 000000001e5e4000 CR4: 00000000003506f0
>>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
>>> Call Trace:
>>> <TASK>
>>> wake_up_pollfree include/linux/wait.h:271 [inline]
>>> signalfd_cleanup+0x42/0x60 fs/signalfd.c:38
>>> __cleanup_sighand kernel/fork.c:1596 [inline]
>>> __cleanup_sighand+0x72/0xb0 kernel/fork.c:1593
>>> __exit_signal kernel/exit.c:159 [inline]
>>> release_task+0xc02/0x17e0 kernel/exit.c:200
>>> wait_task_zombie kernel/exit.c:1117 [inline]
>>> wait_consider_task+0x2fa6/0x3b80 kernel/exit.c:1344
>>> do_wait_thread kernel/exit.c:1407 [inline]
>>> do_wait+0x6ca/0xce0 kernel/exit.c:1524
>>> kernel_wait4+0x14c/0x260 kernel/exit.c:1687
>>> __do_sys_wait4+0x13f/0x150 kernel/exit.c:1715
>>> do_syscall_x64 arch/x86/entry/common.c:50 [inline]
>>> do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
>>> entry_SYSCALL_64_after_hwframe+0x44/0xae
>>> RIP: 0033:0x7facd6682386
>>> Code: 0f 1f 40 00 31 c9 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 49 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 90 48 83 ec 28 89 54 24 14 48 89 74 24
>>> RSP: 002b:00007ffdb91adef8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
>>> RAX: ffffffffffffffda RBX: 000000000000c646 RCX: 00007facd6682386
>>> RDX: 0000000040000001 RSI: 00007ffdb91adf14 RDI: 00000000ffffffff
>>> RBP: 0000000000000f17 R08: 0000000000000032 R09: 00007ffdb91ec080
>>> R10: 0000000000000000 R11: 0000000000000246 R12: 431bde82d7b634db
>>> R13: 00007ffdb91adf14 R14: 0000000000000000 R15: 0000000000000000
>>> </TASK>
>>>
>>>
>>> ---
>>> This report 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 [email protected].
>>>
>>> syzbot will keep track of this issue. See:
>>> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>>> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
>>> syzbot can test patches for this issue, for details see:
>>> https://goo.gl/tpsmEJ#testing-patches
>>
>> --
>> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
>> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
>> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/CANn89iK3tP3rANSWM7_%3DimMeMcUknT0U2GyfA9W4v12ad6_PkQ%40mail.gmail.com.
--
Pavel Begunkov
On 1/5/22 17:37, Pavel Begunkov wrote:
> On 1/5/22 15:52, Eric Biggers wrote:
>> [+io_uring list and maintainers]
>>
>> This appears to be the known bug in io_uring where it doesn't POLLFREE
>> notifications. See previous discussion:
>> https://lore.kernel.org/all/[email protected]/
>
> We've got some fixing and groundwork done, but not POLLFREE yet.
> Great to have a repro, thanks
#syz test: https://github.com/isilence/linux.git pollfree_test1
Almost identical to how Eric did it for aio, let's try it out
>> On Wed, Jan 05, 2022 at 07:42:10AM -0800, 'Eric Dumazet' via syzkaller-bugs wrote:
>>> On Wed, Jan 5, 2022 at 7:37 AM syzbot
>>> <[email protected]> wrote:
>>>>
>>>> Hello,
>>>>
>>>> syzbot found the following issue on:
>>>>
>>>> HEAD commit: 6b8d4927540e Add linux-next specific files for 20220104
>>>> git tree: linux-next
>>>> console output: https://syzkaller.appspot.com/x/log.txt?x=159d88e3b00000
>>>> kernel config: https://syzkaller.appspot.com/x/.config?x=45c9bbbf2ae8e3d3
>>>> dashboard link: https://syzkaller.appspot.com/bug?extid=5426c7ed6868c705ca14
>>>> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
>>>> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=117be65db00000
>>>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15a75c8db00000
>>>>
>>>
>>> C repro looks legit, point to an io_uring issue.
>>>
>>>> The issue was bisected to:
>>>
>>> Please ignore the bisection.
>>>
>>>>
>>>> commit e4b8954074f6d0db01c8c97d338a67f9389c042f
>>>> Author: Eric Dumazet <[email protected]>
>>>> Date: Tue Dec 7 01:30:37 2021 +0000
>>>>
>>>> netlink: add net device refcount tracker to struct ethnl_req_info
>>>>
>>>> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12bca4e3b00000
>>>> final oops: https://syzkaller.appspot.com/x/report.txt?x=11bca4e3b00000
>>>> console output: https://syzkaller.appspot.com/x/log.txt?x=16bca4e3b00000
>>>>
>>>> IMPORTANT: if you fix the issue, please add the following tag to the commit:
>>>> Reported-by: [email protected]
>>>> Fixes: e4b8954074f6 ("netlink: add net device refcount tracker to struct ethnl_req_info")
>>>>
>>>> ------------[ cut here ]------------
>>>> WARNING: CPU: 0 PID: 3604 at kernel/sched/wait.c:245 __wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:246
>>>> Modules linked in:
>>>> CPU: 0 PID: 3604 Comm: syz-executor714 Not tainted 5.16.0-rc8-next-20220104-syzkaller #0
>>>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
>>>> RIP: 0010:__wake_up_pollfree+0x40/0x50 kernel/sched/wait.c:245
>>>> Code: f3 ff ff 48 8d 6b 40 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 80 3c 02 00 75 11 48 8b 43 40 48 39 c5 75 03 5b 5d c3 <0f> 0b 5b 5d c3 48 89 ef e8 13 d8 69 00 eb e5 cc 48 c1 e7 06 48 63
>>>> RSP: 0018:ffffc90001aaf9f8 EFLAGS: 00010083
>>>> RAX: ffff88801cd623f0 RBX: ffff88801bec8048 RCX: 0000000000000000
>>>> RDX: 1ffff110037d9011 RSI: 0000000000000004 RDI: 0000000000000001
>>>> RBP: ffff88801bec8088 R08: 0000000000000000 R09: ffff88801bec804b
>>>> R10: ffffed10037d9009 R11: 0000000000000000 R12: ffff88801bec8040
>>>> R13: ffff88801e029d40 R14: dffffc0000000000 R15: ffff88807eb50000
>>>> FS: 00005555573ad300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
>>>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>>>> CR2: 00000000200000c0 CR3: 000000001e5e4000 CR4: 00000000003506f0
>>>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>>>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
>>>> Call Trace:
>>>> <TASK>
>>>> wake_up_pollfree include/linux/wait.h:271 [inline]
>>>> signalfd_cleanup+0x42/0x60 fs/signalfd.c:38
>>>> __cleanup_sighand kernel/fork.c:1596 [inline]
>>>> __cleanup_sighand+0x72/0xb0 kernel/fork.c:1593
>>>> __exit_signal kernel/exit.c:159 [inline]
>>>> release_task+0xc02/0x17e0 kernel/exit.c:200
>>>> wait_task_zombie kernel/exit.c:1117 [inline]
>>>> wait_consider_task+0x2fa6/0x3b80 kernel/exit.c:1344
>>>> do_wait_thread kernel/exit.c:1407 [inline]
>>>> do_wait+0x6ca/0xce0 kernel/exit.c:1524
>>>> kernel_wait4+0x14c/0x260 kernel/exit.c:1687
>>>> __do_sys_wait4+0x13f/0x150 kernel/exit.c:1715
>>>> do_syscall_x64 arch/x86/entry/common.c:50 [inline]
>>>> do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
>>>> entry_SYSCALL_64_after_hwframe+0x44/0xae
>>>> RIP: 0033:0x7facd6682386
>>>> Code: 0f 1f 40 00 31 c9 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 49 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 90 48 83 ec 28 89 54 24 14 48 89 74 24
>>>> RSP: 002b:00007ffdb91adef8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
>>>> RAX: ffffffffffffffda RBX: 000000000000c646 RCX: 00007facd6682386
>>>> RDX: 0000000040000001 RSI: 00007ffdb91adf14 RDI: 00000000ffffffff
>>>> RBP: 0000000000000f17 R08: 0000000000000032 R09: 00007ffdb91ec080
>>>> R10: 0000000000000000 R11: 0000000000000246 R12: 431bde82d7b634db
>>>> R13: 00007ffdb91adf14 R14: 0000000000000000 R15: 0000000000000000
>>>> </TASK>
>>>>
>>>>
>>>> ---
>>>> This report 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 [email protected].
>>>>
>>>> syzbot will keep track of this issue. See:
>>>> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>>>> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
>>>> syzbot can test patches for this issue, for details see:
>>>> https://goo.gl/tpsmEJ#testing-patches
>>>
>>> --
>>> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
>>> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
>>> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/CANn89iK3tP3rANSWM7_%3DimMeMcUknT0U2GyfA9W4v12ad6_PkQ%40mail.gmail.com.
>
--
Pavel Begunkov
Hello,
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-and-tested-by: [email protected]
Tested on:
commit: 59fb37ef io_uring: pollfree
git tree: https://github.com/isilence/linux.git pollfree_test1
kernel config: https://syzkaller.appspot.com/x/.config?x=d2aaa2946b030309
dashboard link: https://syzkaller.appspot.com/bug?extid=5426c7ed6868c705ca14
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
Note: testing is done by a robot and is best-effort only.