From: syzbot ci <syzbot+cid81af4ef4a45835b@syzkaller.appspotmail.com>
To: frank.li@vivo.com, glaubitz@physik.fu-berlin.de,
hengyul@cs.unc.edu, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org, slava@dubeyko.com
Cc: syzbot@lists.linux.dev, syzkaller-bugs@googlegroups.com
Subject: [syzbot ci] Re: hfs: fall back to buffered I/O for direct writes past phys_size
Date: Sat, 31 Oct 2026 01:59:45 -0700 [thread overview]
Message-ID: <6ae5ae01.78e51036.124520.0002.GAE@google.com> (raw)
In-Reply-To: <20261030042903.4160506-1-hengyul@cs.unc.edu>
syzbot ci has tested the following series
[v1] hfs: fall back to buffered I/O for direct writes past phys_size
https://lore.kernel.org/all/20261030042903.4160506-1-hengyul@cs.unc.edu
* [PATCH 1/2] hfs: fall back to buffered I/O for direct writes past phys_size
* [PATCH 2/2] hfs: remove the dead grow path from hfs_file_truncate()
and found the following issue:
WARNING in hfs_file_truncate
Full report is available here:
https://ci.syzbot.org/series/f8323fc4-a62a-40ea-9106-bff8391323a3
***
WARNING in hfs_file_truncate
tree: axboe
URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/axboe/linux.git
base: a804c5742bff224d4cb4d25dd383554d598be32b
arch: amd64
compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8
config: https://ci.syzbot.org/builds/734131df-1170-4dc7-a0ec-85ffb659aeec/config
syz repro: https://ci.syzbot.org/findings/95638e3e-6c06-4f46-a68b-e468dc287d1e/syz_repro
------------[ cut here ]------------
inode->i_size > HFS_I(inode)->phys_size
WARNING: fs/hfs/extent.c:494 at hfs_file_truncate+0x7cf/0xa50 fs/hfs/extent.c:494, CPU#1: syz.2.19/5839
Modules linked in:
CPU: 1 UID: 0 PID: 5839 Comm: syz.2.19 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:hfs_file_truncate+0x7cf/0xa50 fs/hfs/extent.c:494
Code: 8b 05 ed eb db 11 48 3b 84 24 20 01 00 00 75 1f 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 88 09 33 09 cc e8 02 10 0b ff 90 <0f> 0b 90 eb 9b e8 67 00 30 09 44 89 e9 80 e1 07 80 c1 03 38 c1 0f
RSP: 0018:ffffc900034afaa0 EFLAGS: 00010293
RAX: ffffffff82bca45e RBX: 1ffff92000695f68 RCX: ffff88810ca50000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000852
RBP: ffffc900034afc08 R08: ffffc900034afb97 R09: 0000000000000000
R10: ffffc900034afb60 R11: fffff52000695f73 R12: 0000000000000000
R13: ffff88816b59b100 R14: dffffc0000000000 R15: 0000000000000852
FS: 00007f4cc5ac36c0(0000) GS:ffff8882a7c97000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560c8ef2a008 CR3: 00000001bd922000 CR4: 00000000000006f0
Call Trace:
<TASK>
hfs_inode_setattr+0x4d0/0x730 fs/hfs/inode.c:698
notify_change+0xbba/0xea0 fs/attr.c:556
do_truncate+0x1c2/0x250 fs/open.c:68
do_ftruncate+0x4d4/0x580 fs/open.c:194
ksys_ftruncate fs/open.c:206 [inline]
__do_sys_ftruncate fs/open.c:211 [inline]
__se_sys_ftruncate fs/open.c:209 [inline]
__x64_sys_ftruncate+0x8f/0xe0 fs/open.c:209
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4cc4b9f559
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:00007f4cc5ac3028 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00007f4cc4e25fa0 RCX: 00007f4cc4b9f559
RDX: 0000000000000000 RSI: 0000000000000852 RDI: 0000000000000004
RBP: 00007f4cc4c36b20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4cc4e26038 R14: 00007f4cc4e25fa0 R15: 00007ffcf07cc2c8
</TASK>
***
If these findings have caused you to resend the series or submit a
separate fix, please add the following tag to your commit message:
Tested-by: syzbot@syzkaller.appspotmail.com
---
This report is generated by a bot. It may contain errors.
syzbot ci engineers can be reached at syzkaller@googlegroups.com.
To test a fix for this bug, please reply with `#syz test`
(on a separate line) and attach the patch to the email.
Notes:
- The patch will be applied on top of the tested series (as an
incremental fix).
- To test a new version of the whole series, please send it directly
to syzbot@lists.linux.dev.
- Arguments like custom git repos and branches are not supported.
prev parent reply other threads:[~2026-10-31 8:59 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-30 4:29 [PATCH 0/2] hfs: fall back to buffered I/O for direct writes past phys_size Hengyu Liang
2026-10-30 4:29 ` [PATCH 1/2] " Hengyu Liang
2026-10-30 4:29 ` [PATCH 2/2] hfs: remove the dead grow path from hfs_file_truncate() Hengyu Liang
2026-10-31 8:59 ` syzbot ci [this message]
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