general protection fault in netif_napi_del

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 675cc038 Linux 4.19.167
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12ce69f7500000
kernel config: https://syzkaller.appspot.com/x/.config?x=25b512beb95e2b66
dashboard link: https://syzkaller.appspot.com/bug?extid=4058b5d8f5ba736208a6
compiler: gcc (GCC) 10.1.0-syz 20200507

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4058b5...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 11638 Comm: kworker/u4:2 Not tainted 4.19.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:flush_gro_hash net/core/dev.c:6233 [inline]
RIP: 0010:netif_napi_del+0x1fe/0x380 net/core/dev.c:6248
Code: 28 00 0f 85 10 01 00 00 49 39 ec 48 8b 5d 00 75 05 eb 2d 48 89 c3 e8 01 68 d1 fa 48 89 ef e8 a9 ba fa ff 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 d6 00 00 00 49 39 dc 48 8b 03 48 89 dd 75 d3
RSP: 0018:ffff888044dcf9b8 EFLAGS: 00010a02
RAX: 171ffffd1ffffb76 RBX: b8ffffe8ffffdbb0 RCX: ffffffff868e27bb
RDX: 0000000000000000 RSI: ffffffff86936a07 RDI: 0000000000000001
RBP: ffffe8ffffdbb0b9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffe8ffffdbb0b8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffe8ffffdbb078
FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feb9c021d40 CR3: 00000000b5333000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
gro_cells_destroy net/core/gro_cells.c:102 [inline]
gro_cells_destroy+0x10b/0x340 net/core/gro_cells.c:92
ip_tunnel_dev_free+0x15/0x60 net/ipv4/ip_tunnel.c:965
netdev_run_todo+0x6d2/0xab0 net/core/dev.c:8987
ip_tunnel_delete_nets+0x3d8/0x580 net/ipv4/ip_tunnel.c:1079
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+0x33f/0x460 kernel/kthread.c:259
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:
---[ end trace a9d1b0d517a293e7 ]---
RIP: 0010:flush_gro_hash net/core/dev.c:6233 [inline]
RIP: 0010:netif_napi_del+0x1fe/0x380 net/core/dev.c:6248
Code: 28 00 0f 85 10 01 00 00 49 39 ec 48 8b 5d 00 75 05 eb 2d 48 89 c3 e8 01 68 d1 fa 48 89 ef e8 a9 ba fa ff 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 d6 00 00 00 49 39 dc 48 8b 03 48 89 dd 75 d3
RSP: 0018:ffff888044dcf9b8 EFLAGS: 00010a02
RAX: 171ffffd1ffffb76 RBX: b8ffffe8ffffdbb0 RCX: ffffffff868e27bb
RDX: 0000000000000000 RSI: ffffffff86936a07 RDI: 0000000000000001
RBP: ffffe8ffffdbb0b9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffe8ffffdbb0b8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffe8ffffdbb078
FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feb9c021d40 CR3: 00000000925bf000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

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