syzbot
general protection fault in wb_workfn (2)
Status:
fixed on 2018/07/09 18:05
Subsystems:
fs
[Documentation on labels]
Reported-by: syzbot+4a7438e774b21ddd8eca@syzkaller.appspotmail.com
Fix commit:
3ee7e8697d58
bdi: Fix another oops in wb_workfn()
First crash: 3009d, last: 2976d
Sample crash report:
nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead.
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 0 PID: 32 Comm: kworker/u4:2 Not tainted 4.18.0-rc1+ #109
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfn
RIP: 0010:dev_name include/linux/device.h:1019 [inline]
RIP: 0010:wb_workfn+0x19d/0x1760 fs/fs-writeback.c:1937
Code: 48 c1 ea 03 80 3c 02 00 0f 85 96 14 00 00 48 8b 9b 08 06 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 50 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 39 14 00 00 4c 8b 63 50 4d 85 e4 0f 84 c5 0e 00
RSP: 0018:ffff8801d9527250 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff814fee45
RDX: 000000000000000a RSI: ffffffff81d18545 RDI: 0000000000000050
RBP: ffff8801d9527730 R08: ffff8801d9512080 R09: ffffed003b5c46d6
R10: ffffed003b5c46d6 R11: ffff8801dae236b3 R12: 0000000000000001
R13: 1ffff1003b2a4f33 R14: ffff8801d9527708 R15: ffff8801c243f698
FS: 0000000000000000(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020606ff0 CR3: 0000000008e6a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000023eee571 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
process_one_work+0xc73/0x1ba0 kernel/workqueue.c:2153
process_scheduled_works kernel/workqueue.c:2212 [inline]
worker_thread+0x9ed/0x13c0 kernel/workqueue.c:2301
kthread+0x345/0x410 kernel/kthread.c:240
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
Modules linked in:
Dumping ftrace buffer:
(ftrace buffer empty)
---[ end trace dfe6c54ac53f15c7 ]---
RIP: 0010:dev_name include/linux/device.h:1019 [inline]
RIP: 0010:wb_workfn+0x19d/0x1760 fs/fs-writeback.c:1937
Code: 48 c1 ea 03 80 3c 02 00 0f 85 96 14 00 00 48 8b 9b 08 06 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 50 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 39 14 00 00 4c 8b 63 50 4d 85 e4 0f 84 c5 0e 00
RSP: 0018:ffff8801d9527250 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff814fee45
RDX: 000000000000000a RSI: ffffffff81d18545 RDI: 0000000000000050
RBP: ffff8801d9527730 R08: ffff8801d9512080 R09: ffffed003b5c46d6
R10: ffffed003b5c46d6 R11: ffff8801dae236b3 R12: 0000000000000001
R13: 1ffff1003b2a4f33 R14: ffff8801d9527708 R15: ffff8801c243f698
FS: 0000000000000000(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020606ff0 CR3: 0000000008e6a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000023eee571 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Struck through repros no longer work on HEAD.