From: syzbot <syzbot+3fee0864af947db7a9c4@syzkaller.appspotmail.com>
To: adilger.kernel@dilger.ca, jack@suse.cz,
libaokun@linux.alibaba.com, linux-ext4@vger.kernel.org,
linux-kernel@vger.kernel.org, ojaswin@linux.ibm.com,
ritesh.list@gmail.com, syzkaller-bugs@googlegroups.com,
tytso@mit.edu, yi.zhang@huawei.com
Subject: [syzbot] [ext4?] WARNING in __ext4_handle_dirty_metadata
Date: Mon, 27 Jul 2026 20:04:31 -0700 [thread overview]
Message-ID: <6a681c3f.70955b6c.323240.0050.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: d326f83e819c Merge tag 'net-7.2-rc5' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16c75232580000
kernel config: https://syzkaller.appspot.com/x/.config?x=20c9876b0f77b546
dashboard link: https://syzkaller.appspot.com/bug?extid=3fee0864af947db7a9c4
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-d326f83e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/754d3e5fbfc7/vmlinux-d326f83e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c70e5cfffd37/bzImage-d326f83e.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3fee0864af947db7a9c4@syzkaller.appspotmail.com
loop0: detected capacity change from 0 to 4096
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
------------[ cut here ]------------
!buffer_uptodate(bh)
WARNING: fs/buffer.c:1093 at mark_buffer_dirty+0x299/0x410 fs/buffer.c:1093, CPU#0: syz.0.0/5329
Modules linked in:
CPU: 0 UID: 0 PID: 5329 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:mark_buffer_dirty+0x299/0x410 fs/buffer.c:1093
Code: 4c 89 f7 e8 19 0e d9 ff 49 8b 3e be 40 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 d4 5e fb ff e8 7f e1 69 ff eb 8c e8 78 e1 69 ff 90 <0f> 0b 90 e9 a5 fd ff ff e8 6a e1 69 ff 90 0f 0b 90 e9 cf fd ff ff
RSP: 0018:ffffc9000fcd7420 EFLAGS: 00010287
RAX: ffffffff825ca058 RBX: ffff88801224ad20 RCX: 0000000000100000
RDX: ffffc9000f2a9000 RSI: 00000000000820c2 RDI: 00000000000820c3
RBP: 0000000000001601 R08: ffff88801224ad27 R09: 1ffff110024495a4
R10: dffffc0000000000 R11: ffffed10024495a5 R12: dffffc0000000000
R13: ffff88801224ad20 R14: 0000000000000000 R15: 1ffff110024495a4
FS: 00007f65e6f976c0(0000) GS:ffff88808c546000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000101000 CR3: 0000000012312000 CR4: 0000000000352ef0
Call Trace:
<TASK>
__ext4_handle_dirty_metadata+0x2e3/0x800 fs/ext4/ext4_jbd2.c:396
ext4_do_update_inode fs/ext4/inode.c:5751 [inline]
ext4_mark_iloc_dirty+0x15b1/0x1cc0 fs/ext4/inode.c:6404
__ext4_mark_inode_dirty+0x4a7/0x700 fs/ext4/inode.c:6610
ext4_write_end+0x553/0x9e0 fs/ext4/inode.c:1481
ext4_da_write_end+0x89/0xcc0 fs/ext4/inode.c:3297
generic_perform_write+0x612/0x8f0 mm/filemap.c:4379
ext4_buffered_write_iter+0xcb/0x370 fs/ext4/file.c:316
ext4_file_write_iter+0x947/0x1c70 fs/ext4/file.c:-1
aio_write+0x5cd/0x870 fs/aio.c:1687
__io_submit_one fs/aio.c:-1 [inline]
io_submit_one+0x798/0x13d0 fs/aio.c:2106
__do_sys_io_submit fs/aio.c:2165 [inline]
__se_sys_io_submit+0x195/0x340 fs/aio.c:2135
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: 0033:0x7f65e619de99
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:00007f65e6f96fe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1
RAX: ffffffffffffffda RBX: 00007f65e6425fa0 RCX: 00007f65e619de99
RDX: 0000200000000540 RSI: 0000000000000008 RDI: 00007f65e6f76000
RBP: 00007f65e6233eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f65e6426038 R14: 00007f65e6425fa0 R15: 00007ffff6e87f78
</TASK>
---
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reply other threads:[~2026-07-28 3:04 UTC|newest]
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