syzbot


divide error in dbNextAG

Status: auto-closed as invalid on 2021/12/22 21:17
Reported-by: syzbot+bbcb6dfec634ea33e4db@syzkaller.appspotmail.com
First crash: 972d, last: 972d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 divide error in dbNextAG (2) jfs C error 10 473d 767d 0/1 upstream: reported C repro on 2022/03/17 14:18
upstream divide error in dbNextAG jfs syz error 2 769d 765d 22/26 fixed on 2023/02/24 13:50

Sample crash report:
divide error: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 19130 Comm: syz-executor.0 Not tainted 4.19.204-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:dbNextAG+0xff/0x530 fs/jfs/jfs_dmap.c:615
Code: df 48 89 c1 48 89 04 24 83 e0 07 48 c1 e9 03 0f b6 0c 11 48 89 c2 83 c2 03 38 ca 7c 08 84 c9 0f 85 8a 03 00 00 44 89 f0 31 d2 <41> f7 74 24 14 49 89 c6 49 8d 44 24 20 48 89 c2 48 89 44 24 18 48
RSP: 0018:ffff88822f49fac0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880ab338900 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8880a19dcc08
RBP: ffff888018bc1910 R08: 0000000000000000 R09: ffffed101433ba0a
R10: ffff8880a19dd057 R11: 0000000000074071 R12: ffff8880a19dcc00
R13: ffff88802f86f9a8 R14: 0000000000000000 R15: 0000000000000001
FS:  00007f9f56ece700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000014a53ad CR3: 00000002307ec000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 diAlloc+0x7ea/0x1440 fs/jfs/jfs_imap.c:1380
 ialloc+0x8c/0x970 fs/jfs/jfs_inode.c:69
 jfs_mkdir.part.0+0x131/0x870 fs/jfs/namei.c:237
 jfs_mkdir+0x3f/0x60 fs/jfs/namei.c:222
 vfs_mkdir+0x508/0x7a0 fs/namei.c:3819
 do_mkdirat+0x262/0x2d0 fs/namei.c:3842
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4656f7
Code: 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 53 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9f56ecdfa8 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004656f7
RDX: 0000000000000000 RSI: 00000000000001ff RDI: 0000000020002940
RBP: 00007f9f56ece040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000020002940 R14: 00007f9f56ece000 R15: 0000000000000000
Modules linked in:
---[ end trace af3457dcb4799cd9 ]---
RIP: 0010:dbNextAG+0xff/0x530 fs/jfs/jfs_dmap.c:615
Code: df 48 89 c1 48 89 04 24 83 e0 07 48 c1 e9 03 0f b6 0c 11 48 89 c2 83 c2 03 38 ca 7c 08 84 c9 0f 85 8a 03 00 00 44 89 f0 31 d2 <41> f7 74 24 14 49 89 c6 49 8d 44 24 20 48 89 c2 48 89 44 24 18 48
RSP: 0018:ffff88822f49fac0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880ab338900 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8880a19dcc08
RBP: ffff888018bc1910 R08: 0000000000000000 R09: ffffed101433ba0a
R10: ffff8880a19dd057 R11: 0000000000074071 R12: ffff8880a19dcc00
R13: ffff88802f86f9a8 R14: 0000000000000000 R15: 0000000000000001
FS:  00007f9f56ece700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
attempt to access beyond end of device
loop2: rw=0, want=184, limit=178
metapage_read_end_io: I/O error
CR2: 0000000000970004 CR3: 00000002307ec000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	df 48 89             	fisttps -0x77(%rax)
   3:	c1 48 89 04          	rorl   $0x4,-0x77(%rax)
   7:	24 83                	and    $0x83,%al
   9:	e0 07                	loopne 0x12
   b:	48 c1 e9 03          	shr    $0x3,%rcx
   f:	0f b6 0c 11          	movzbl (%rcx,%rdx,1),%ecx
  13:	48 89 c2             	mov    %rax,%rdx
  16:	83 c2 03             	add    $0x3,%edx
  19:	38 ca                	cmp    %cl,%dl
  1b:	7c 08                	jl     0x25
  1d:	84 c9                	test   %cl,%cl
  1f:	0f 85 8a 03 00 00    	jne    0x3af
  25:	44 89 f0             	mov    %r14d,%eax
  28:	31 d2                	xor    %edx,%edx
* 2a:	41 f7 74 24 14       	divl   0x14(%r12) <-- trapping instruction
  2f:	49 89 c6             	mov    %rax,%r14
  32:	49 8d 44 24 20       	lea    0x20(%r12),%rax
  37:	48 89 c2             	mov    %rax,%rdx
  3a:	48 89 44 24 18       	mov    %rax,0x18(%rsp)
  3f:	48                   	rex.W

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/08/24 21:17 linux-4.19.y 59456c9cc40c b599f2fc .config console log report info ci2-linux-4-19 divide error in dbNextAG
* Struck through repros no longer work on HEAD.