syzbot


BUG: unable to handle kernel paging request in do_split

Status: upstream: reported C repro on 2024/08/09 00:52
Reported-by: syzbot+a89498ad74b918e9892c@syzkaller.appspotmail.com
First crash: 58d, last: 35d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: unable to handle kernel paging request in do_split ext4 C inconclusive 17 85d 98d 27/28 fixed on 2024/08/14 03:44
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/09/14 08:19 59m retest repro android13-5.10-lts OK log
2024/08/23 03:43 5m retest repro android13-5.10-lts report log

Sample crash report:
EXT4-fs error (device loop0): ext4_xattr_inode_iget:409: comm syz-executor304: error while reading EA inode 2 err=-117
EXT4-fs (loop0): 1 orphan inode deleted
EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue
BUG: unable to handle page fault for address: ffffed1121b3d6fe
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 23fff2067 P4D 23fff2067 
PUD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 290 Comm: syz-executor304 Not tainted 5.10.222-syzkaller-01494-gfd58936f3c1f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:do_split+0x1454/0x2310 fs/ext4/namei.c:2011
Code: f8 48 c1 e8 03 0f b6 04 10 84 c0 48 89 74 24 10 0f 85 7c 0c 00 00 46 8b 34 e6 41 8d 44 24 ff 48 8d 1c c6 48 89 d8 48 c1 e8 03 <0f> b6 04 10 84 c0 0f 85 85 0c 00 00 8b 1b 44 89 f7 89 de e8 64 06
RSP: 0018:ffffc90000b372e0 EFLAGS: 00010a02
RAX: 1ffff11121b3d6fe RBX: ffff88890d9eb7f0 RCX: ffff8881200962c0
RDX: dffffc0000000000 RSI: ffff88810d9eb7f8 RDI: ffff88810d9eb7f8
RBP: ffffc90000b374d0 R08: ffffffff81e4a331 R09: ffffffff81da0931
R10: 0000000000000007 R11: ffff8881200962c0 R12: 0000000000000000
R13: 0000000000000400 R14: 000000002b74e18c R15: 0000000000000000
FS:  0000555555a2d380(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffed1121b3d6fe CR3: 0000000117d34000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 make_indexed_dir+0xd7d/0x1340 fs/ext4/namei.c:2299
 ext4_add_entry+0xdcf/0x1280 fs/ext4/namei.c:2411
 ext4_rename fs/ext4/namei.c:4054 [inline]
 ext4_rename2+0x2663/0x4070 fs/ext4/namei.c:4327
 vfs_rename+0x9fb/0xeb0 fs/namei.c:4474
 do_renameat2+0xa56/0x1240 fs/namei.c:4619
 __do_sys_rename fs/namei.c:4670 [inline]
 __se_sys_rename fs/namei.c:4668 [inline]
 __x64_sys_rename+0x86/0x90 fs/namei.c:4668
 do_syscall_64+0x34/0x70
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fcde8565979
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffcfe17db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007fffcfe17f98 RCX: 00007fcde8565979
RDX: 00007fcde8565979 RSI: 0000000020000f40 RDI: 00000000200003c0
RBP: 00007fcde85d8610 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fffcfe17f88 R14: 0000000000000001 R15: 0000000000000001
Modules linked in:
CR2: ffffed1121b3d6fe
---[ end trace 4734256b309655f4 ]---
RIP: 0010:do_split+0x1454/0x2310 fs/ext4/namei.c:2011
Code: f8 48 c1 e8 03 0f b6 04 10 84 c0 48 89 74 24 10 0f 85 7c 0c 00 00 46 8b 34 e6 41 8d 44 24 ff 48 8d 1c c6 48 89 d8 48 c1 e8 03 <0f> b6 04 10 84 c0 0f 85 85 0c 00 00 8b 1b 44 89 f7 89 de e8 64 06
RSP: 0018:ffffc90000b372e0 EFLAGS: 00010a02
RAX: 1ffff11121b3d6fe RBX: ffff88890d9eb7f0 RCX: ffff8881200962c0
RDX: dffffc0000000000 RSI: ffff88810d9eb7f8 RDI: ffff88810d9eb7f8
RBP: ffffc90000b374d0 R08: ffffffff81e4a331 R09: ffffffff81da0931
R10: 0000000000000007 R11: ffff8881200962c0 R12: 0000000000000000
R13: 0000000000000400 R14: 000000002b74e18c R15: 0000000000000000
FS:  0000555555a2d380(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffed1121b3d6fe CR3: 0000000117d34000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	f8                   	clc
   1:	48 c1 e8 03          	shr    $0x3,%rax
   5:	0f b6 04 10          	movzbl (%rax,%rdx,1),%eax
   9:	84 c0                	test   %al,%al
   b:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)
  10:	0f 85 7c 0c 00 00    	jne    0xc92
  16:	46 8b 34 e6          	mov    (%rsi,%r12,8),%r14d
  1a:	41 8d 44 24 ff       	lea    -0x1(%r12),%eax
  1f:	48 8d 1c c6          	lea    (%rsi,%rax,8),%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	0f b6 04 10          	movzbl (%rax,%rdx,1),%eax <-- trapping instruction
  2e:	84 c0                	test   %al,%al
  30:	0f 85 85 0c 00 00    	jne    0xcbb
  36:	8b 1b                	mov    (%rbx),%ebx
  38:	44 89 f7             	mov    %r14d,%edi
  3b:	89 de                	mov    %ebx,%esi
  3d:	e8                   	.byte 0xe8
  3e:	64 06                	fs (bad)

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/09 00:50 android13-5.10-lts fd58936f3c1f 61405512 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-10 BUG: unable to handle kernel paging request in do_split
2024/08/31 04:34 android13-5.10-lts 1c5354a314ea 1eda0d14 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-10 BUG: unable to handle kernel paging request in do_split
* Struck through repros no longer work on HEAD.