general protection fault in nl80211_netlink_notify

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 4520f06b Linux 4.14.175
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16cee5c7e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=93cf891381c0c347
dashboard link: https://syzkaller.appspot.com/bug?extid=cfd935bc557e3e8b9f28
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+cfd935...@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
Modules linked in:
CPU: 0 PID: 25939 Comm: syz-executor.4 Not tainted 4.14.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888087624440 task.stack: ffff888052f58000
RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline]
RIP: 0010:nl80211_netlink_notify net/wireless/nl80211.c:15155 [inline]
RIP: 0010:nl80211_netlink_notify+0x135/0x840 net/wireless/nl80211.c:15138
RSP: 0018:ffff888052f5fc10 EFLAGS: 00010206
RAX: 0000000000000044 RBX: dffffc0000000000 RCX: ffffc90009300000
RDX: 0000000000002e19 RSI: ffffffff85decba7 RDI: ffff888000162288
RBP: 0000000000000220 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888052f5fd70
R13: ffff888000162368 R14: fffffffffffffff8 R15: ffff888000162368
FS: 00007ff4f8120700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc50620b3f8 CR3: 000000009392b000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
notifier_call_chain+0x107/0x1a0 kernel/notifier.c:93
__blocking_notifier_call_chain kernel/notifier.c:317 [inline]
__blocking_notifier_call_chain kernel/notifier.c:304 [inline]
blocking_notifier_call_chain kernel/notifier.c:328 [inline]
blocking_notifier_call_chain+0x79/0x90 kernel/notifier.c:325
netlink_release+0x10af/0x13c0 net/netlink/af_netlink.c:756
__sock_release+0xcd/0x2b0 net/socket.c:602
sock_close+0x15/0x20 net/socket.c:1139
__fput+0x25f/0x790 fs/file_table.c:210
task_work_run+0x113/0x190 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:191 [inline]
exit_to_usermode_loop+0x1d6/0x220 arch/x86/entry/common.c:164
prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x416421
RSP: 002b:00007ff4f811f9c0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000416421
RDX: 0000000000000200 RSI: 00007ff4f811fa40 RDI: 0000000000000007
RBP: 0000000000000007 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007ff4f811fa40
R13: 0000000000000bc2 R14: 00000000004d80c8 R15: 000000000076bfac
Code: 92 88 48 bb 00 00 00 00 00 fc ff df 48 c1 e8 03 48 01 d8 48 89 44 24 10 e8 f9 7a 7b fb 49 8d ae 28 02 00 00 48 89 e8 48 c1 e8 03 <80> 3c 18 00 0f 85 36 06 00 00 49 8b 86 28 02 00 00 4c 8d b8 50
RIP: __read_once_size include/linux/compiler.h:183 [inline] RSP: ffff888052f5fc10
RIP: nl80211_netlink_notify net/wireless/nl80211.c:15155 [inline] RSP: ffff888052f5fc10
RIP: nl80211_netlink_notify+0x135/0x840 net/wireless/nl80211.c:15138 RSP: ffff888052f5fc10
---[ end trace 14c1cab9ca6f86f3 ]---


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[syzbot]

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