syzbot

 sign-in | mailing list | source | docs | 🏰
🐞 Open [1348]
≡ Subsystems
🐞 Fixed [7091]
🐞 Invalid [18734]
⬇ Missing Backports [220]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
Total Repo Heatmap Subsystems Heatmap
✨ AI
💬 Send us feedback

kernel BUG in dtSplitRoot

Status: upstream: reported C repro on 2025/12/06 08:38
Subsystems: jfs
[Documentation on labels]
Reported-by: syzbot+a099d674daa27a9272db@syzkaller.appspotmail.com
First crash: 166d, last: 78d
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
b296248f-d0ef-4340-aadb-2965531c1f34 assessment-security 💥 kernel BUG in dtSplitRoot 2026/05/14 17:04 2026/05/14 17:04 2026/05/14 17:05 6ccb967e465e832a7bfd7a116ad00d52a0923a5d failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 128 From /app/workdir/repo/linux * branch HEAD -> FETCH_HEAD Updating files: 19% (17848/91184) Updating files: 20% (18237/91184) Updating files: 21% (19149/91184) Updating files: 22% (20061/91184) Updating files: 23% (20973/91184) Updating files: 24% (21885/91184) Updating files: 25% (22796/91184) Updating files: 26% (23708/91184) Updating files: 27% (24620/91184) Updating files: 28% (25532/91184) Updating files: 29% (26444/91184) Updating files: 30% (27356/91184) Updating files: 30% (27588/91184) Updating files: 31% (28268/91184) Updating files: 32% (29179/91184) error: unable to write file drivers/acpi/acpica/tbfind.c error: unable to write file drivers/acpi/acpica/tbinstal.c error: unable to write file drivers/acpi/acpica/tbprint.c error: unable to write file drivers/acpi/acpica/tbutils.c error: unable to write file drivers/acpi/acpica/tbxface.c error: unable to write file drivers/acpi/acpica/tbxfload.c error: unable to write file drivers/acpi/acpica/tbxfroot.c error: unable to write file drivers/acpi/acpica/utaddress.c error: unable to write file drivers/acpi/acpica/utalloc.c error: unable to write file drivers/acpi/acpica/utascii.c error: unable to write file drivers/acpi/acpica/utbuffer.c error: unable to write file drivers/acpi/acpica/utcache.c error: unable to write file drivers/acpi/acpica/utcksum.c error: unable to write file drivers/acpi/acpica/utcopy.c error: unable to write file drivers/acpi/acpica/utdebug.c error: unable to write file drivers/acpi/acpica/utdecode.c error: unable to write file drivers/acpi/acpica/utdelete.c error: unable to write file drivers/acpi/acpica/uterror.c error: unable to write file drivers/acpi/acpica/uteval.c error: unable to write file drivers/acpi/acpica/utexcep.c error: unable to write file drivers/acpi/acpica/utglobal.c error: unable to write file drivers/acpi/acpica/uthex.c error: unable to write file drivers/acpi/acpica/utids.c error: unable to write file drivers/acpi/acpica/utinit.c error: unable to write file drivers/acpi/acpica/utlock.c error: unable to write file drivers/acpi/acpica/utmath.c error: unable to write file drivers/acpi/acpica/utmisc.c error: unable to write file drivers/acpi/acpica/utmutex.c error: unable to write file drivers/acpi/acpica/utnonansi.c error: unable to write file drivers/acpi/acpica/utobject.c error: unable to write file drivers/acpi/acpica/utosi.c error: unable to write file drivers/acpi/acpica/utownerid.c error: unable to write file drivers/acpi/acpica/utpredef.c error: unable to write file drivers/acpi/acpica/utprint.c error: unable to write file drivers/acpi/acpica/utresdecode.c error: unable to write file drivers/acpi/acpica/utresrc.c error: unable to write file drivers/acpi/acpica/utstate.c error: unable to write file drivers/acpi/acpica/utstring.c error: unable to write file drivers/acpi/acpica/utstrsuppt.c error: unable to write file drivers/acpi/acpica/utstrtoul64.c error: unable to write file drivers/acpi/acpica/uttrack.c error: unable to write file drivers/acpi/acpica/utuuid.c error: unable to write file drivers/acpi/acpica/utxface.c error: unable to write file drivers/acpi/acpica/utxferror.c error: unable to write file drivers/acpi/acpica/utxfinit.c error: unable to write file drivers/acpi/acpica/utxfmutex.c fatal: cannot create directory at 'drivers/acpi/apei': No space left on device
▶ ▼ Discussions (3)
Title Replies (including bot) Last reply
[PATCH] jfs: fix directory tree corruption in dtSplitRoot() 1 (1) 2025/12/07 06:58
[PATCH] jfs: fix directory tree corruption in dtSplitRoot() 2 (2) 2025/12/07 06:55
[syzbot] [jfs?] kernel BUG in dtSplitRoot 0 (4) 2025/12/07 06:05
▶ ▼ Last patch testing requests (6)
Created Duration User Patch Repo Result
2026/05/09 19:12 22m retest repro upstream error
2026/02/28 18:10 9m retest repro upstream report log
2025/12/16 10:25 15m retest repro upstream report log
2025/12/07 06:05 17m kartikey406@gmail.com patch upstream report log
2025/12/07 05:21 20m kartikey406@gmail.com patch upstream report log
2025/12/07 04:57 16m kartikey406@gmail.com patch upstream report log

Sample crash report:
UFO tlock:0xffffc9000152d5e8
BUG at fs/jfs/jfs_dtree.c:1942 assert(dtlck->index == 0)
------------[ cut here ]------------
kernel BUG at fs/jfs/jfs_dtree.c:1942!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5663 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:dtSplitRoot+0x1694/0x16c0 fs/jfs/jfs_dtree.c:1942
Code: e9 49 f3 ff ff e8 2c fc 77 fe 48 c7 c7 e0 88 a4 8b 48 c7 c6 c0 87 a4 8b ba 96 07 00 00 48 c7 c1 60 89 a4 8b e8 3d 01 df fd 90 <0f> 0b e8 05 fc 77 fe 48 c7 c7 e0 88 a4 8b 48 c7 c6 c0 87 a4 8b ba
RSP: 0018:ffffc9000d2972a8 EFLAGS: 00010246
RAX: 0000000000000038 RBX: 0000000000001000 RCX: c529552525a5ed00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc9000152d6db R08: ffff88801fe24253 R09: 1ffff11003fc484a
R10: dffffc0000000000 R11: ffffed1003fc484b R12: dffffc0000000000
R13: 1ffff920002a5adb R14: 0000000000000002 R15: ffffc9000152d6c0
FS:  0000555582889500(0000) GS:ffff88808d722000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe1757d0e9c CR3: 000000004fc9e000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 dtSplitUp fs/jfs/jfs_dtree.c:1244 [inline]
 dtInsert+0x2525/0x5f40 fs/jfs/jfs_dtree.c:871
 jfs_create+0x6c8/0xa80 fs/jfs/namei.c:137
 lookup_open fs/namei.c:3866 [inline]
 open_last_lookups fs/namei.c:3965 [inline]
 path_openat+0x188f/0x3b80 fs/namei.c:4201
 do_filp_open+0x1fa/0x410 fs/namei.c:4231
 do_sys_openat2+0x121/0x1c0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_creat fs/open.c:1530 [inline]
 __se_sys_creat fs/open.c:1524 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1524
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f94e718f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe798e7728 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f94e73e5fa0 RCX: 00007f94e718f7c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000580
RBP: 00007f94e7213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f94e73e5fa0 R14: 00007f94e73e5fa0 R15: 0000000000000002
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dtSplitRoot+0x1694/0x16c0 fs/jfs/jfs_dtree.c:1942
Code: e9 49 f3 ff ff e8 2c fc 77 fe 48 c7 c7 e0 88 a4 8b 48 c7 c6 c0 87 a4 8b ba 96 07 00 00 48 c7 c1 60 89 a4 8b e8 3d 01 df fd 90 <0f> 0b e8 05 fc 77 fe 48 c7 c7 e0 88 a4 8b 48 c7 c6 c0 87 a4 8b ba
RSP: 0018:ffffc9000d2972a8 EFLAGS: 00010246
RAX: 0000000000000038 RBX: 0000000000001000 RCX: c529552525a5ed00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc9000152d6db R08: ffff88801fe24253 R09: 1ffff11003fc484a
R10: dffffc0000000000 R11: ffffed1003fc484b R12: dffffc0000000000
R13: 1ffff920002a5adb R14: 0000000000000002 R15: ffffc9000152d6c0
FS:  0000555582889500(0000) GS:ffff88808d722000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2ca51ff000 CR3: 000000004fc9e000 CR4: 0000000000352ef0

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/02 10:21 upstream 1d18101a644e d1b870e1 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci-snapshot-upstream-root kernel BUG in dtSplitRoot
2026/02/14 17:55 upstream 770aaedb461a 1e62d198 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in dtSplitRoot
2026/01/06 19:03 upstream 54e82e93ca93 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in dtSplitRoot
2025/12/02 08:32 upstream 1d18101a644e d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in dtSplitRoot
* Struck through repros no longer work on HEAD.