======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.7.1592/14102 is trying to acquire lock:
ffff88802bd83370 (&p->frag_sem){++++}-{4:4}, at: __configfs_open_file+0xd8/0x7d0 fs/configfs/file.c:304

but task is already holding lock:
ffff8880355d2dc8 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x7d0/0x1c10 security/integrity/ima/ima_main.c:319

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:646 [inline]
       __mutex_lock+0x197/0x15a0 kernel/locking/mutex.c:821
       process_measurement+0x7d0/0x1c10 security/integrity/ima/ima_main.c:319
       ima_file_check+0xdc/0x130 security/integrity/ima/ima_main.c:686
       security_file_post_open+0xb3/0x260 security/security.c:2776
       do_open fs/namei.c:4853 [inline]
       path_openat+0x1748/0x20f0 fs/namei.c:5016
       do_file_open+0x23e/0x4a0 fs/namei.c:5045
       do_sys_openat2+0x115/0x200 fs/open.c:1442
       do_sys_open fs/open.c:1448 [inline]
       __do_sys_openat fs/open.c:1464 [inline]
       __se_sys_openat fs/open.c:1459 [inline]
       __x64_sys_openat+0x138/0x170 fs/open.c:1459
       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 (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+0x48/0x1c0 include/linux/fs/super.h:125
       mnt_want_write+0x41/0x90 fs/namespace.c:531
       lookup_open+0x1f7/0x1ae0 fs/namei.c:4459
       open_last_lookups fs/namei.c:4774 [inline]
       path_openat+0x70c/0x20f0 fs/namei.c:5013
       do_file_open+0x23e/0x4a0 fs/namei.c:5045
       file_open_name fs/open.c:1400 [inline]
       filp_open+0x16d/0x1d0 fs/open.c:1417
       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

-> #1 (&common->filesem){+.+.}-{4:4}:
       down_write+0x91/0x200 kernel/locking/rwsem.c:1631
       fsg_store_file+0x163/0x400 drivers/usb/gadget/function/storage_common.c:452
       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

-> #0 (&p->frag_sem){++++}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3209 [inline]
       check_prevs_add kernel/locking/lockdep.c:3328 [inline]
       validate_chain kernel/locking/lockdep.c:3952 [inline]
       __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
       lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
       down_read+0x45/0x320 kernel/locking/rwsem.c:1574
       __configfs_open_file+0xd8/0x7d0 fs/configfs/file.c:304
       do_dentry_open+0x80e/0x1360 fs/open.c:1000
       vfs_open+0x43/0x350 fs/open.c:1107
       dentry_open+0x61/0xa0 fs/open.c:1149
       ima_calc_file_hash+0x15f/0x890 security/integrity/ima/ima_crypto.c:269
       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+0xdc/0x130 security/integrity/ima/ima_main.c:686
       security_file_post_open+0xb3/0x260 security/security.c:2776
       do_open fs/namei.c:4853 [inline]
       path_openat+0x1748/0x20f0 fs/namei.c:5016
       do_file_open+0x23e/0x4a0 fs/namei.c:5045
       do_sys_openat2+0x115/0x200 fs/open.c:1442
       do_sys_open fs/open.c:1448 [inline]
       __do_sys_openat fs/open.c:1464 [inline]
       __se_sys_openat fs/open.c:1459 [inline]
       __x64_sys_openat+0x138/0x170 fs/open.c:1459
       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:
  &p->frag_sem --> sb_writers#5 --> &ima_iint_mutex_key[depth]

 Possible unsafe locking scenario:

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

 *** DEADLOCK ***

locks held by syz.7.1592/14102: 1, last CPU#0:
 #0: ffff8880355d2dc8 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x7d0/0x1c10 security/integrity/ima/ima_main.c:319

stack backtrace:
CPU: 0 UID: 0 PID: 14102 Comm: syz.7.1592 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2087
 check_noncircular+0x12f/0x150 kernel/locking/lockdep.c:2219
 check_prev_add kernel/locking/lockdep.c:3209 [inline]
 check_prevs_add kernel/locking/lockdep.c:3328 [inline]
 validate_chain kernel/locking/lockdep.c:3952 [inline]
 __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
 down_read+0x45/0x320 kernel/locking/rwsem.c:1574
 __configfs_open_file+0xd8/0x7d0 fs/configfs/file.c:304
 do_dentry_open+0x80e/0x1360 fs/open.c:1000
 vfs_open+0x43/0x350 fs/open.c:1107
 dentry_open+0x61/0xa0 fs/open.c:1149
 ima_calc_file_hash+0x15f/0x890 security/integrity/ima/ima_crypto.c:269
 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+0xdc/0x130 security/integrity/ima/ima_main.c:686
 security_file_post_open+0xb3/0x260 security/security.c:2776
 do_open fs/namei.c:4853 [inline]
 path_openat+0x1748/0x20f0 fs/namei.c:5016
 do_file_open+0x23e/0x4a0 fs/namei.c:5045
 do_sys_openat2+0x115/0x200 fs/open.c:1442
 do_sys_open fs/open.c:1448 [inline]
 __do_sys_openat fs/open.c:1464 [inline]
 __se_sys_openat fs/open.c:1459 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1459
 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: 0033:0x7f4a3599fb19
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:00007f4a368f5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f4a35c25fa0 RCX: 00007f4a3599fb19
RDX: 0000000000000001 RSI: 0000200000001100 RDI: ffffffffffffff9c
RBP: 00007f4a35a37b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4a35c26038 R14: 00007f4a35c25fa0 R15: 00007fff0503a8d8
 </TASK>