WARNING in default_device_exit_batch

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 399849e4 Linux 4.19.131
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=152adb97100000
kernel config: https://syzkaller.appspot.com/x/.config?x=eada6d424d8bae1d
dashboard link: https://syzkaller.appspot.com/bug?extid=109977bd364b4f38b22f
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+109977...@syzkaller.appspotmail.com

audit: type=1400 audit(1594281793.226:264): avc: denied { setattr } for pid=6424 comm="syz-fuzzer" path="/root/syzkaller-testdir147629826/syzkaller.qRi2wT/731/proc/1/attr" dev="proc" ino=100795 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=dir permissive=1
bond5 (unregistering): Released all slaves
bond4 (unregistering): Released all slaves
------------[ cut here ]------------
WARNING: CPU: 0 PID: 30592 at net/core/dev.c:8207 rollback_registered_many.cold+0x169/0x1b8 net/core/dev.c:8207
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 30592 Comm: kworker/u4:0 Not tainted 4.19.131-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
panic+0x26a/0x50e kernel/panic.c:186
__warn.cold+0x20/0x61 kernel/panic.c:541
report_bug+0x262/0x2b0 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:178 [inline]
fixup_bug arch/x86/kernel/traps.c:173 [inline]
do_error_trap+0x1d7/0x310 arch/x86/kernel/traps.c:296
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038
RIP: 0010:rollback_registered_many.cold+0x169/0x1b8 net/core/dev.c:8207
Code: 44 24 08 eb cd 48 89 c7 48 89 44 24 08 e8 dd dd e8 fb 48 8b 44 24 08 eb cf e8 b1 bf b2 fb 48 c7 c7 c0 2d 2a 88 e8 e4 d2 9d fb <0f> 0b e9 1a c0 ff ff e8 99 bf b2 fb 48 c7 c7 c0 2d 2a 88 e8 cc d2
RSP: 0018:ffff8880498e7988 EFLAGS: 00010282
RAX: 0000000000000024 RBX: ffff8880a5601e00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8154cd91 RDI: ffffed100931cf23
RBP: ffff8880498e7b60 R08: 0000000000000024 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000086aecf01 R14: ffffffff84559090 R15: ffff8880498e7a50
unregister_netdevice_many.part.0+0x1a/0x300 net/core/dev.c:9310
unregister_netdevice_many net/core/dev.c:9309 [inline]
default_device_exit_batch+0x2fa/0x3c0 net/core/dev.c:9781
ops_exit_list+0xf9/0x150 net/core/net_namespace.c:156
cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:553
process_one_work+0x864/0x1570 kernel/workqueue.c:2155
worker_thread+0x64c/0x1130 kernel/workqueue.c:2298
kthread+0x30b/0x410 kernel/kthread.c:246
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Kernel Offset: disabled
Rebooting in 86400 seconds..


---
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[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b850307b Linux 4.14.184
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=173f9333100000
kernel config: https://syzkaller.appspot.com/x/.config?x=ddc0f08dd6b981c5
dashboard link: https://syzkaller.appspot.com/bug?extid=20ae47299fd039d41635
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:

Reported-by: syzbot+20ae47...@syzkaller.appspotmail.com

bond71 (unregistering): Released all slaves
bond70 (unregistering): Released all slaves
bond69 (unregistering): Released all slaves
bond68 (unregistering): Released all slaves
------------[ cut here ]------------
WARNING: CPU: 1 PID: 252 at net/core/dev.c:7226 rollback_registered_many+0x85d/0xa70 net/core/dev.c:7226

Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 252 Comm: kworker/u4:2 Not tainted 4.14.184-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:

__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x283 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
__warn.cold+0x2f/0x30 kernel/panic.c:547
report_bug+0x20a/0x248 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:rollback_registered_many+0x85d/0xa70 net/core/dev.c:7226
RSP: 0018:ffff8880a95ffa80 EFLAGS: 00010297
RAX: ffff8880a95f2040 RBX: ffff8880a95ffb98 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8880a95f2940 RDI: ffff88804f581e40
RBP: ffff88804f581e40 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8880a95ffab8 R14: ffff88808d634000 R15: ffffffff83d19440
unregister_netdevice_many.part.0+0x16/0x1d0 net/core/dev.c:8281
unregister_netdevice_many net/core/dev.c:8280 [inline]
default_device_exit_batch+0x2dd/0x380 net/core/dev.c:8742
ops_exit_list.isra.0+0xef/0x140 net/core/net_namespace.c:145
cleanup_net+0x3bb/0x820 net/core/net_namespace.c:484
process_one_work+0x7c0/0x14c0 kernel/workqueue.c:2116
worker_thread+0x5d7/0x1080 kernel/workqueue.c:2250
kthread+0x30d/0x420 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.

[syzbot]