syzbot


general protection fault in mpage_process_page_bufs

Status: auto-closed as invalid on 2020/09/11 10:41
Reported-by: syzbot+820eef85d00b034f8f46@syzkaller.appspotmail.com
First crash: 776d, last: 776d

Sample crash report:
overlayfs: failed to resolve './file0': -2
overlayfs: failed to resolve 'file0': -2
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: 1 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfn (flush-8:0)
task: ffff8880a9832140 task.stack: ffff8880a9840000
RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:325 [inline]
RIP: 0010:buffer_locked include/linux/buffer_head.h:120 [inline]
RIP: 0010:mpage_process_page_bufs+0xd6/0x520 fs/ext4/inode.c:2321
RSP: 0018:ffff8880a9847478 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000000c
RDX: 0000000000000000 RSI: ffff888000403c78 RDI: ffff888000403c80
RBP: 00000000000008ce R08: 0000000000000001 R09: 0000000000000003
R10: ffff8880a9832a40 R11: ffff8880a9832140 R12: ffff8880a98477c0
R13: dffffc0000000000 R14: ffffed1015308efe R15: ffff8880a98477f4
FS:  0000000000000000(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c425e6c000 CR3: 000000008b0bc000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 mpage_prepare_extent_to_map+0x43e/0xa50 fs/ext4/inode.c:2708
 ext4_writepages+0x144a/0x2fd0 fs/ext4/inode.c:2899
 do_writepages+0xd0/0x250 mm/page-writeback.c:2361
 __writeback_single_inode+0xda/0x1140 fs/fs-writeback.c:1367
 writeback_sb_inodes+0x475/0xcf0 fs/fs-writeback.c:1631
 wb_writeback+0x247/0xba0 fs/fs-writeback.c:1807
 wb_do_writeback fs/fs-writeback.c:1939 [inline]
 wb_workfn+0x29c/0xe60 fs/fs-writeback.c:1975
 process_one_work+0x813/0x1540 kernel/workqueue.c:2116
 worker_thread+0x5d1/0x1070 kernel/workqueue.c:2250
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: ff df d3 e0 49 8d 44 06 ff 4d 89 fe 48 d3 f8 49 c1 ee 03 48 89 44 24 08 4d 01 ee 89 44 24 10 e8 a1 17 9c ff 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 6b 03 00 00 48 8b 03 a8 04 0f 85 c7 01 00 
RIP: constant_test_bit arch/x86/include/asm/bitops.h:325 [inline] RSP: ffff8880a9847478
RIP: buffer_locked include/linux/buffer_head.h:120 [inline] RSP: ffff8880a9847478
RIP: mpage_process_page_bufs+0xd6/0x520 fs/ext4/inode.c:2321 RSP: ffff8880a9847478
---[ end trace 7d40187ebd02488a ]---

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2020/05/14 10:40 linux-4.14.y ab9dfda23248 2d572622 .config log report