======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.3.2318/13383 is trying to acquire lock:
ffff888033ac4e58 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_reset_action_flags security/integrity/ima/ima_main.c:708 [inline]
ffff888033ac4e58 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_file_truncate+0xb9/0x180 security/integrity/ima/ima_main.c:723

but task is already holding lock:
ffff888031ef2510 (sb_writers#5){.+.+}-{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#5){.+.+}-{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+0x1ec/0x1a60 fs/namei.c:4451
       open_last_lookups fs/namei.c:4767 [inline]
       path_openat+0x67c/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/0xe00 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+0x33a/0x430 fs/configfs/file.c:229
       new_sync_write fs/read_write.c:595 [inline]
       vfs_write+0x61e/0xbb0 fs/read_write.c:687
       ksys_write+0x156/0x270 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+0x97/0x200 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+0x2ba/0x620 fs/configfs/file.c:88
       __kernel_read+0x4d3/0x970 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+0x45d/0x8a0 security/integrity/ima/ima_crypto.c:280
       ima_collect_measurement+0x521/0xa10 security/integrity/ima/ima_api.c:300
       process_measurement+0x1282/0x1c20 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+0x148a/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+0x97/0x200 kernel/locking/rwsem.c:1574
       fill_read_buffer fs/configfs/file.c:66 [inline]
       configfs_read_iter+0x1cf/0x620 fs/configfs/file.c:88
       __kernel_read+0x4d3/0x970 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+0x45d/0x8a0 security/integrity/ima/ima_crypto.c:280
       ima_collect_measurement+0x521/0xa10 security/integrity/ima/ima_api.c:300
       process_measurement+0x1282/0x1c20 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+0x148a/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/rtmutex_api.c:559 [inline]
       mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578
       configfs_read_iter+0x73/0x620 fs/configfs/file.c:86
       __kernel_read+0x4d3/0x970 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+0x45d/0x8a0 security/integrity/ima/ima_crypto.c:280
       ima_collect_measurement+0x521/0xa10 security/integrity/ima/ima_api.c:300
       process_measurement+0x1282/0x1c20 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+0x148a/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+0x1520/0x2ce0 kernel/locking/lockdep.c:5253
       lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886
       __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline]
       mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578
       ima_reset_action_flags security/integrity/ima/ima_main.c:708 [inline]
       ima_file_truncate+0xb9/0x180 security/integrity/ima/ima_main.c:723
       security_file_truncate+0xf1/0x240 security/security.c:2771
       handle_truncate fs/namei.c:4298 [inline]
       do_open fs/namei.c:4841 [inline]
       path_openat+0x156e/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

other info that might help us debug this:

Chain exists of:
  &ima_iint_mutex_key[depth] --> &common->filesem --> sb_writers#5

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(sb_writers#5);
                               lock(&common->filesem);
                               lock(sb_writers#5);
  lock(&ima_iint_mutex_key[depth]);

 *** DEADLOCK ***

locks held by syz.3.2318/13383: 1, last CPU#0:
 #0: ffff888031ef2510 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494

stack backtrace:
CPU: 0 UID: 0 PID: 13383 Comm: syz.3.2318 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(lazy)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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+0x1520/0x2ce0 kernel/locking/lockdep.c:5253
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886
 __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline]
 mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578
 ima_reset_action_flags security/integrity/ima/ima_main.c:708 [inline]
 ima_file_truncate+0xb9/0x180 security/integrity/ima/ima_main.c:723
 security_file_truncate+0xf1/0x240 security/security.c:2771
 handle_truncate fs/namei.c:4298 [inline]
 do_open fs/namei.c:4841 [inline]
 path_openat+0x156e/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
RIP: 0033:0x7f6c5f4fe0d9
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:00007f6c5d756028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f6c5f785fa0 RCX: 00007f6c5f4fe0d9
RDX: 000000000000275a RSI: 00002000000001c0 RDI: ffffffffffffff9c
RBP: 00007f6c5f595024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6c5f786038 R14: 00007f6c5f785fa0 R15: 00007ffe590f5488
 </TASK>