general protection fault in __queue_work

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    3717f613f48d Merge branch 'core-rcu-for-linus' of git://gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=156e100b200000
kernel config:  https://syzkaller.appspot.com/x/.config?x=73d88a42238825ad
dashboard link: https://syzkaller.appspot.com/bug?extid=b26e643d0aa2822e9c87
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+b26e643d0aa2822e9c87@xxxxxxxxxxxxxxxxxxxxxxxxx

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: 23765 Comm: syz-executor.2 Not tainted 5.0.0+ #8
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:strlen+0x1f/0xa0 lib/string.c:483
Code: 00 66 2e 0f 1f 84 00 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 55 48  
89 fa 48 89 e5 48 c1 ea 03 41 54 49 89 fc 53 48 83 ec 08 <0f> b6 04 02 48  
89 fa 83 e2 07 38 d0 7f 04 84 c0 75 4d 41 80 3c 24
RSP: 0018:ffff88801b96f080 EFLAGS: 00010082
RAX: dffffc0000000000 RBX: ffff88809fe08428 RCX: 0000000000000000
kobject: 'loop0' (00000000c40c285a): kobject_uevent_env
RDX: 1d00000000200062 RSI: ffff8880ae82c831 RDI: e800000001000313
RBP: ffff88801b96f098 R08: 0000000000000000 R09: 0000000000000001
R10: ffffed1015d05bcf R11: 0000000000000001 R12: e800000001000313
R13: 0000000000000000 R14: ffff8880ae82c831 R15: ffff88801b96f168
FS:  00007f08e786c700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
kobject: 'loop0' (00000000c40c285a): fill_kobj_path: path  
= '/devices/virtual/block/loop0'
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000004f616000 CR4: 00000000001426f0
Call Trace:
 trace_event_get_offsets_lock_acquire include/trace/events/lock.h:13  
[inline]
 perf_trace_lock_acquire+0xb9/0x580 include/trace/events/lock.h:13
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0x29c/0x3f0 kernel/locking/lockdep.c:3840
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:329 [inline]
 __queue_work+0x23d/0x1180 kernel/workqueue.c:1437
 __queue_delayed_work+0x1d6/0x270 kernel/workqueue.c:1542
 mod_delayed_work_on+0xd8/0x200 kernel/workqueue.c:1616
 mod_delayed_work include/linux/workqueue.h:542 [inline]
 addrconf_mod_dad_work+0x3f/0xa0 net/ipv6/addrconf.c:328
 addrconf_dad_start+0x76/0xb0 net/ipv6/addrconf.c:4012
 addrconf_add_linklocal+0x28c/0x3c0 net/ipv6/addrconf.c:3191
 addrconf_addr_gen+0x34d/0x3a0 net/ipv6/addrconf.c:3314
 addrconf_dev_config+0x1ea/0x2c0 net/ipv6/addrconf.c:3357
 addrconf_notify+0x3c5/0x2280 net/ipv6/addrconf.c:3592
 notifier_call_chain+0xc7/0x240 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
 call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
 call_netdevice_notifiers net/core/dev.c:1765 [inline]
 __dev_notify_flags+0x121/0x2c0 net/core/dev.c:7605
 dev_change_flags+0x10d/0x170 net/core/dev.c:7643
 devinet_ioctl+0x1396/0x1c60 net/ipv4/devinet.c:1104
 inet_ioctl+0x1fc/0x370 net/ipv4/af_inet.c:954
 packet_ioctl+0xcb/0x2b0 net/packet/af_packet.c:4099
 sock_do_ioctl+0xde/0x300 net/socket.c:972
 sock_ioctl+0x32b/0x610 net/socket.c:1096
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457f29
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f08e786bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457f29
RDX: 0000000020000240 RSI: 0000000000008914 RDI: 0000000000000004
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f08e786c6d4
R13: 00000000004c35d0 R14: 00000000004d6408 R15: 00000000ffffffff
Modules linked in:
---[ end trace 2c7811a1cf58c24e ]---
RIP: 0010:strlen+0x1f/0xa0 lib/string.c:483
Code: 00 66 2e 0f 1f 84 00 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 55 48  
89 fa 48 89 e5 48 c1 ea 03 41 54 49 89 fc 53 48 83 ec 08 <0f> b6 04 02 48  
89 fa 83 e2 07 38 d0 7f 04 84 c0 75 4d 41 80 3c 24
RSP: 0018:ffff88801b96f080 EFLAGS: 00010082
RAX: dffffc0000000000 RBX: ffff88809fe08428 RCX: 0000000000000000
RDX: 1d00000000200062 RSI: ffff8880ae82c831 RDI: e800000001000313
RBP: ffff88801b96f098 R08: 0000000000000000 R09: 0000000000000001
R10: ffffed1015d05bcf R11: 0000000000000001 R12: e800000001000313
kobject: 'kvm' (000000007d76adfd): kobject_uevent_env
R13: 0000000000000000 R14: ffff8880ae82c831 R15: ffff88801b96f168
FS:  00007f08e786c700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000004f616000 CR4: 00000000001426f0


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