syzbot


kernel BUG in ext4_write_inline_data (5)

Status: upstream: reported on 2026/06/09 08:13
Subsystems: ext4
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+53c8bd6136cfbe85197e@syzkaller.appspotmail.com
First crash: 6d12h, last: 2d05h
✨ AI Jobs (1)
ID Workflow Result Correct Ext Bug ID Bug Created Started Finished Revision Error
a82c38f3-aadb-49f7-b23a-f481967861cf assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ kernel BUG in ext4_write_inline_data (5) 2026/06/09 13:21 2026/06/09 13:21 2026/06/09 14:16 c36c07f6c1f2230a36374cbd22235f635e8f9284
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ext4?] kernel BUG in ext4_write_inline_data (5) 0 (1) 2026/06/09 08:13
Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 kernel BUG in ext4_write_inline_data ext4 -1 C 4 1219d 1315d 0/1 upstream: reported C repro on 2022/11/04 18:44
upstream kernel BUG at fs/ext4/inline.c:LINE! ext4 -1 C done done 76 1243d 2066d 22/29 fixed on 2023/02/24 13:50
upstream kernel BUG in ext4_write_inline_data ext4 -1 C error 36 697d 1182d 27/29 fixed on 2024/08/22 01:52
upstream kernel BUG in ext4_write_inline_data (4) ext4 -1 C error 13 35d 129d 29/29 fixed on 2026/05/21 07:49
linux-6.1 kernel BUG in ext4_write_inline_data origin:upstream -1 C error 13 120d 458d 0/3 upstream: reported C repro on 2025/03/10 13:01
android-6-1 kernel BUG in ext4_write_inline_data origin:lts -1 C error error 32 31d 1074d 0/2 upstream: reported C repro on 2023/07/02 21:30
upstream kernel BUG in ext4_write_inline_data (3) ext4 -1 C error 8 162d 271d 29/29 fixed on 2026/01/07 12:29
linux-4.19 kernel BUG in ext4_write_inline_data_end ext4 -1 C error 12 1196d 1943d 0/1 upstream: reported C repro on 2021/02/14 13:39
upstream kernel BUG in ext4_write_inline_data (2) ext4 -1 C error 46 353d 567d 29/29 fixed on 2025/07/08 00:33
android-5-10 kernel BUG in ext4_write_inline_data ext4 -1 C error inconclusive 3 1215d 1313d 2/2 fixed on 2023/05/04 14:51
android-54 kernel BUG in ext4_write_inline_data -1 C 3 1275d 1313d 2/2 fixed on 2023/04/05 17:17

Sample crash report:
EXT4-fs (loop3): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
------------[ cut here ]------------
kernel BUG at fs/ext4/inline.c:240!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 7011 Comm: syz.3.214 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:ext4_write_inline_data+0x43c/0x440 fs/ext4/inline.c:240
Code: c1 38 c1 0f 8c 19 ff ff ff 48 89 df 49 89 d7 e8 6a 1e b0 ff 4c 89 fa e9 06 ff ff ff e8 7d f1 48 ff 90 0f 0b e8 75 f1 48 ff 90 <0f> 0b 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f
RSP: 0018:ffffc900053ff808 EFLAGS: 00010293
RAX: ffffffff827b7b1b RBX: 0000000000017000 RCX: ffff888030e49ec0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff8880609c740a R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100551c081 R12: 000000000000003c
R13: ffffc900053ff8e0 R14: 0000000000016000 R15: ffff8880609c6cf8
FS:  00007f56a94766c0(0000) GS:ffff888126287000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa9139bc000 CR3: 0000000059be8000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 ext4_write_inline_data_end+0x332/0xaf0 fs/ext4/inline.c:825
 generic_perform_write+0x5f7/0x8b0 mm/filemap.c:4346
 ext4_buffered_write_iter+0xd0/0x3a0 fs/ext4/file.c:316
 ext4_file_write_iter+0x299/0x1c10 fs/ext4/file.c:-1
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x629/0xba0 fs/read_write.c:688
 ksys_pwrite64 fs/read_write.c:795 [inline]
 __do_sys_pwrite64 fs/read_write.c:803 [inline]
 __se_sys_pwrite64 fs/read_write.c:800 [inline]
 __x64_sys_pwrite64+0x19c/0x230 fs/read_write.c:800
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f56ab21ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f56a9476028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007f56ab495fa0 RCX: 00007f56ab21ce59
RDX: 000000000000fdef RSI: 0000200000000140 RDI: 0000000000000004
RBP: 00007f56ab2b2d6f R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000fecc R11: 0000000000000246 R12: 0000000000000000
R13: 00007f56ab496038 R14: 00007f56ab495fa0 R15: 00007ffcb8942108
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_write_inline_data+0x43c/0x440 fs/ext4/inline.c:240
Code: c1 38 c1 0f 8c 19 ff ff ff 48 89 df 49 89 d7 e8 6a 1e b0 ff 4c 89 fa e9 06 ff ff ff e8 7d f1 48 ff 90 0f 0b e8 75 f1 48 ff 90 <0f> 0b 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f
RSP: 0018:ffffc900053ff808 EFLAGS: 00010293
RAX: ffffffff827b7b1b RBX: 0000000000017000 RCX: ffff888030e49ec0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff8880609c740a R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100551c081 R12: 000000000000003c
R13: ffffc900053ff8e0 R14: 0000000000016000 R15: ffff8880609c6cf8
FS:  00007f56a94766c0(0000) GS:ffff888126287000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa9139bc000 CR3: 0000000059be8000 CR4: 00000000003526f0

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/09 14:59 upstream 2d3090a8aeb5 c36c07f6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ext4_write_inline_data
2026/06/05 08:09 upstream 9154c4af7829 197909be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ext4_write_inline_data
* Struck through repros no longer work on HEAD.