From: syzbot <syzbot+ecf337bf2c6f75c1ddd8@syzkaller.appspotmail.com>
To: a.hindborg@kernel.org, leitao@debian.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
syzkaller-bugs@googlegroups.com
Subject: [syzbot] [fs?] possible deadlock in ima_path_truncate
Date: Tue, 25 Aug 2026 21:45:44 -0700 [thread overview]
Message-ID: <6a8e6f78.dbb3a75c.7844.0033.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 818bebeb63dd drm/xe: Don't hand out the flat CCS storage a..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17c6be79580000
kernel config: https://syzkaller.appspot.com/x/.config?x=3c35c7e43de75adb
dashboard link: https://syzkaller.appspot.com/bug?extid=ecf337bf2c6f75c1ddd8
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-818bebeb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9adea981957f/vmlinux-818bebeb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6676075cd03e/bzImage-818bebeb.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ecf337bf2c6f75c1ddd8@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.0/5310 is trying to acquire lock:
ffff888043b8ecc0 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_reset_action_flags security/integrity/ima/ima_main.c:708 [inline]
ffff888043b8ecc0 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_path_truncate+0xd3/0x190 security/integrity/ima/ima_main.c:717
but task is already holding lock:
ffff8880347c0460 (sb_writers#11){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (sb_writers#11){.+.+}-{0:0}:
percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
__sb_start_write include/linux/fs/super.h:19 [inline]
sb_start_write+0x4d/0x1d0 include/linux/fs/super.h:125
mnt_want_write+0x41/0x90 fs/namespace.c:494
lookup_open+0x1e6/0x1a40 fs/namei.c:4451
open_last_lookups fs/namei.c:4767 [inline]
path_openat+0x677/0x1d60 fs/namei.c:4997
do_file_open+0x23e/0x4a0 fs/namei.c:5029
file_open_name fs/open.c:1375 [inline]
filp_open+0x16d/0x1d0 fs/open.c:1392
fsg_lun_open+0x6c/0xdf0 drivers/usb/gadget/function/storage_common.c:194
fsg_store_file+0x19e/0x400 drivers/usb/gadget/function/storage_common.c:455
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x337/0x430 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x612/0xba0 fs/read_write.c:687
ksys_write+0x150/0x270 fs/read_write.c:739
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
-> #3 (&common->filesem){++++}-{4:4}:
down_read+0x4a/0x330 kernel/locking/rwsem.c:1574
fsg_show_file+0x2d/0x140 drivers/usb/gadget/function/storage_common.c:339
fill_read_buffer fs/configfs/file.c:68 [inline]
configfs_read_iter+0x2b7/0x620 fs/configfs/file.c:88
__kernel_read+0x4ca/0x960 fs/read_write.c:532
integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28
ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:222 [inline]
ima_calc_file_hash+0x451/0x890 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x51b/0xa00 security/integrity/ima/ima_api.c:300
process_measurement+0x1272/0x1c10 security/integrity/ima/ima_main.c:425
ima_file_check+0xe1/0x130 security/integrity/ima/ima_main.c:685
security_file_post_open+0xb3/0x260 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x1485/0x1d60 fs/namei.c:5000
do_file_open+0x23e/0x4a0 fs/namei.c:5029
do_sys_openat2+0x115/0x200 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1434
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
-> #2 (&p->frag_sem){.+.+}-{4:4}:
down_read+0x4a/0x330 kernel/locking/rwsem.c:1574
fill_read_buffer fs/configfs/file.c:66 [inline]
configfs_read_iter+0x1cc/0x620 fs/configfs/file.c:88
__kernel_read+0x4ca/0x960 fs/read_write.c:532
integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28
ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:222 [inline]
ima_calc_file_hash+0x451/0x890 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x51b/0xa00 security/integrity/ima/ima_api.c:300
process_measurement+0x1272/0x1c10 security/integrity/ima/ima_main.c:425
ima_file_check+0xe1/0x130 security/integrity/ima/ima_main.c:685
security_file_post_open+0xb3/0x260 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x1485/0x1d60 fs/namei.c:5000
do_file_open+0x23e/0x4a0 fs/namei.c:5029
do_sys_openat2+0x115/0x200 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1434
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
-> #1 (&buffer->mutex){+.+.}-{4:4}:
__mutex_lock_common kernel/locking/mutex.c:646 [inline]
__mutex_lock+0x19d/0x1550 kernel/locking/mutex.c:821
configfs_read_iter+0x70/0x620 fs/configfs/file.c:86
__kernel_read+0x4ca/0x960 fs/read_write.c:532
integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28
ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:222 [inline]
ima_calc_file_hash+0x451/0x890 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x51b/0xa00 security/integrity/ima/ima_api.c:300
process_measurement+0x1272/0x1c10 security/integrity/ima/ima_main.c:425
ima_file_check+0xe1/0x130 security/integrity/ima/ima_main.c:685
security_file_post_open+0xb3/0x260 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x1485/0x1d60 fs/namei.c:5000
do_file_open+0x23e/0x4a0 fs/namei.c:5029
do_sys_openat2+0x115/0x200 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1434
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
-> #0 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3181 [inline]
check_prevs_add kernel/locking/lockdep.c:3300 [inline]
validate_chain kernel/locking/lockdep.c:3924 [inline]
__lock_acquire+0x1520/0x2cf0 kernel/locking/lockdep.c:5253
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886
__mutex_lock_common kernel/locking/mutex.c:646 [inline]
__mutex_lock+0x19d/0x1550 kernel/locking/mutex.c:821
ima_reset_action_flags security/integrity/ima/ima_main.c:708 [inline]
ima_path_truncate+0xd3/0x190 security/integrity/ima/ima_main.c:717
security_path_truncate+0x1d0/0x310 security/security.c:1563
vfs_truncate+0x46b/0x540 fs/open.c:116
ksys_truncate+0xf3/0x1c0 fs/open.c:142
__do_sys_truncate fs/open.c:154 [inline]
__se_sys_truncate fs/open.c:152 [inline]
__x64_sys_truncate+0x5b/0x70 fs/open.c:152
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
other info that might help us debug this:
Chain exists of:
&ima_iint_mutex_key[depth] --> &common->filesem --> sb_writers#11
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
rlock(sb_writers#11);
lock(&common->filesem);
lock(sb_writers#11);
lock(&ima_iint_mutex_key[depth]);
*** DEADLOCK ***
locks held by syz.0.0/5310: 1, last CPU#0:
#0: ffff8880347c0460 (sb_writers#11){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
stack backtrace:
CPU: 0 UID: 0 PID: 5310 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
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2059
check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2191
check_prev_add kernel/locking/lockdep.c:3181 [inline]
check_prevs_add kernel/locking/lockdep.c:3300 [inline]
validate_chain kernel/locking/lockdep.c:3924 [inline]
__lock_acquire+0x1520/0x2cf0 kernel/locking/lockdep.c:5253
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886
__mutex_lock_common kernel/locking/mutex.c:646 [inline]
__mutex_lock+0x19d/0x1550 kernel/locking/mutex.c:821
ima_reset_action_flags security/integrity/ima/ima_main.c:708 [inline]
ima_path_truncate+0xd3/0x190 security/integrity/ima/ima_main.c:717
security_path_truncate+0x1d0/0x310 security/security.c:1563
vfs_truncate+0x46b/0x540 fs/open.c:116
ksys_truncate+0xf3/0x1c0 fs/open.c:142
__do_sys_truncate fs/open.c:154 [inline]
__se_sys_truncate fs/open.c:152 [inline]
__x64_sys_truncate+0x5b/0x70 fs/open.c:152
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: 0033:0x7f92a899e0d9
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:00007f92a97d3fe8 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007f92a8c26090 RCX: 00007f92a899e0d9
RDX: 0000000000000000 RSI: 0000000000000c88 RDI: 0000200000000100
RBP: 00007f92a8a35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f92a8c26128 R14: 00007f92a8c26090 R15: 00007ffcdcc3c1d8
</TASK>
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
reply other threads:[~2026-08-26 4:45 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=6a8e6f78.dbb3a75c.7844.0033.GAE@google.com \
--to=syzbot+ecf337bf2c6f75c1ddd8@syzkaller.appspotmail.com \
--cc=a.hindborg@kernel.org \
--cc=leitao@debian.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=syzkaller-bugs@googlegroups.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.