syzbot


kernel BUG in ext4_create_inline_data

Status: upstream: reported C repro on 2025/09/01 23:25
Reported-by: syzbot+66e33d12f694dd7203ab@syzkaller.appspotmail.com
First crash: 22h44m, last: 22h44m
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 kernel BUG in ext4_create_inline_data origin:lts -1 C 1 2d14h 2d14h 0/2 upstream: reported C repro on 2025/08/31 07:46
android-5-10 kernel BUG in ext4_create_inline_data -1 C 2 31d 92d 0/2 upstream: reported C repro on 2025/06/02 09:20

Sample crash report:
------------[ cut here ]------------
kernel BUG at fs/ext4/inline.c:302!
invalid opcode: 0000 [#2] PREEMPT SMP KASAN
CPU: 0 PID: 423 Comm: syz.6.17 Tainted: G      D            syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:ext4_create_inline_data+0x3f6/0x400 fs/ext4/inline.c:302
Code: ff ff e8 3d 0c cd ff e9 16 ff ff ff 89 f9 80 e1 07 fe c1 38 c1 0f 8c 32 ff ff ff e8 24 0c cd ff e9 28 ff ff ff e8 da a6 88 ff <0f> 0b 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 56 53 48 89 fb
RSP: 0018:ffffc90000e07420 EFLAGS: 00010293
RAX: ffffffff81e76286 RBX: 0000000000000000 RCX: ffff8881180ed100
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000e07550 R08: ffff8881180ed100 R09: 0000000000000002
R10: 00000000ffffffc3 R11: 0000000000000000 R12: 1ffff920001c0e88
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88810309dce8
FS:  00007f57a42b96c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558ddc5ec418 CR3: 0000000102bd4000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_prepare_inline_data+0x16c/0x1f0 fs/ext4/inline.c:413
 ext4_try_to_write_inline_data+0x31c/0x1290 fs/ext4/inline.c:691
 ext4_write_begin+0x1ea/0xf70 fs/ext4/inode.c:1205
 generic_perform_write+0x2f6/0x6d0 mm/filemap.c:3882
 ext4_buffered_write_iter+0x36f/0x660 fs/ext4/file.c:285
 ext4_file_write_iter+0x18f/0x13d0 fs/ext4/file.c:-1
 call_write_iter include/linux/fs.h:2282 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x5db/0xca0 fs/read_write.c:584
 ksys_write+0x140/0x240 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:646
 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f57a338ebe9
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:00007f57a42b9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f57a35c5fa0 RCX: 00007f57a338ebe9
RDX: 0000000000000012 RSI: 0000200000000100 RDI: 0000000000000004
RBP: 00007f57a3411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f57a35c6038 R14: 00007f57a35c5fa0 R15: 00007ffd0dfc29b8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_create_inline_data+0x3f6/0x400 fs/ext4/inline.c:302
Code: ff ff e8 3d 0c cd ff e9 16 ff ff ff 89 f9 80 e1 07 fe c1 38 c1 0f 8c 32 ff ff ff e8 24 0c cd ff e9 28 ff ff ff e8 da a6 88 ff <0f> 0b 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 56 53 48 89 fb
RSP: 0018:ffffc90000e27420 EFLAGS: 00010293
RAX: ffffffff81e76286 RBX: 0000000000000000 RCX: ffff8881180ee540
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000e27550 R08: ffff8881180ee540 R09: 0000000000000002
R10: 00000000ffffffc3 R11: 0000000000000000 R12: 1ffff920001c4e88
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88810309ba98
FS:  00007f57a42b96c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6b0620e000 CR3: 0000000102bd4000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/01 23:24 android14-6.1 684ae9bac393 807a3b61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1 (corrupt fs)] [mounted in repro #2 (corrupt fs)] ci2-android-6-1 kernel BUG in ext4_create_inline_data
* Struck through repros no longer work on HEAD.