kernel BUG in tun_attach

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fdd06dc6b0f8 ANDROID: GKI: db845c: Update symbols list and..
git tree: android12-5.10-lts
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1120cba7f00000
kernel config: https://syzkaller.appspot.com/x/.config?x=298c89d0104c8e66
dashboard link: https://syzkaller.appspot.com/bug?extid=e559f12bb7b41ef21d10
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1142a83ff00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12a3ab08080000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e559f1...@syzkaller.appspotmail.com

R10: 00007fc8f0eae700 R11: 0000000000000246 R12: 00007fc8f0fa543c
R13: 00007fc8f0f73004 R14: 74656e2f7665642f R15: 0000000000022000
---[ end trace 5cf33435a999f120 ]---
------------[ cut here ]------------
kernel BUG at include/linux/netdevice.h:518!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 375 Comm: syz-executor382 Tainted: G W 5.10.117-syzkaller-00814-gfdd06dc6b0f8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:napi_enable include/linux/netdevice.h:518 [inline]
RIP: 0010:tun_napi_init drivers/net/tun.c:278 [inline]
RIP: 0010:tun_attach+0x14b3/0x14c0 drivers/net/tun.c:818
Code: 89 df e8 e0 ba b7 fe e9 cf fa ff ff e8 f6 e4 7d fe 48 c7 c7 a0 12 68 86 48 89 de e8 67 7c 7b ff e9 e0 fb ff ff e8 dd e4 7d fe <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 56 41
RSP: 0018:ffffc900009bfb50 EFLAGS: 00010293
RAX: ffffffff82eecd73 RBX: 0000000000000000 RCX: ffff8881067f3b40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900009bfc70 R08: ffffffff82eec175 R09: ffffed10234a3886
R10: ffffed10234a3886 R11: 1ffff110234a3885 R12: ffff88811a51c428
R13: ffff88811d70c980 R14: ffff88811d70c000 R15: dffffc0000000000
FS: 00007fc8f0eae700(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd61403a58 CR3: 0000000106186000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
tun_set_iff+0xadf/0x1100 drivers/net/tun.c:2803
__tun_chr_ioctl+0x8ab/0x2130 drivers/net/tun.c:3084
tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:3360
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl+0x115/0x190 fs/ioctl.c:739
__x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:739
do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fc8f0f1ce29
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc8f0eae308 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fc8f0fa5438 RCX: 00007fc8f0f1ce29
RDX: 0000000020000200 RSI: 00000000400454ca RDI: 0000000000000003
RBP: 00007fc8f0fa5430 R08: 00007fc8f0eae700 R09: 0000000000000000
R10: 00007fc8f0eae700 R11: 0000000000000246 R12: 00007fc8f0fa543c
R13: 00007fc8f0f73004 R14: 74656e2f7665642f R15: 0000000000022000
Modules linked in:
---[ end trace 5cf33435a999f121 ]---
RIP: 0010:napi_enable include/linux/netdevice.h:518 [inline]
RIP: 0010:tun_napi_init drivers/net/tun.c:278 [inline]
RIP: 0010:tun_attach+0x14b3/0x14c0 drivers/net/tun.c:818
Code: 89 df e8 e0 ba b7 fe e9 cf fa ff ff e8 f6 e4 7d fe 48 c7 c7 a0 12 68 86 48 89 de e8 67 7c 7b ff e9 e0 fb ff ff e8 dd e4 7d fe <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 56 41
RSP: 0018:ffffc900009bfb50 EFLAGS: 00010293
RAX: ffffffff82eecd73 RBX: 0000000000000000 RCX: ffff8881067f3b40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900009bfc70 R08: ffffffff82eec175 R09: ffffed10234a3886
R10: ffffed10234a3886 R11: 1ffff110234a3885 R12: ffff88811a51c428
R13: ffff88811d70c980 R14: ffff88811d70c000 R15: dffffc0000000000
FS: 00007fc8f0eae700(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd61403a58 CR3: 0000000106186000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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