====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.1732/10315 is trying to acquire lock: ffff888075b8d480 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x7d0/0x1c10 security/integrity/ima/ima_main.c:319 but task is already holding lock: ffff88807b5c2460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:531 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (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+0x1f7/0x1970 fs/namei.c:4453 open_last_lookups fs/namei.c:4768 [inline] path_openat+0x70c/0x20f0 fs/namei.c:5007 do_file_open+0x23e/0x4a0 fs/namei.c:5039 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:1036 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 (&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:1036 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 (&p->frag_sem){.+.+}-{4:4}: 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:4847 [inline] path_openat+0x1748/0x20f0 fs/namei.c:5010 do_file_open+0x23e/0x4a0 fs/namei.c:5039 do_sys_openat2+0x115/0x200 fs/open.c:1442 do_sys_open fs/open.c:1448 [inline] __do_sys_openat fs/open.c:1788 [inline] __se_sys_openat fs/open.c:1783 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1783 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: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 __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:4847 [inline] path_openat+0x1748/0x20f0 fs/namei.c:5010 do_file_open+0x23e/0x4a0 fs/namei.c:5039 do_sys_openat2+0x115/0x200 fs/open.c:1442 do_sys_open fs/open.c:1448 [inline] __do_sys_openat fs/open.c:1788 [inline] __se_sys_openat fs/open.c:1783 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1783 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.1.1732/10315: 1, last CPU#0: #0: ffff88807b5c2460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:531 stack backtrace: CPU: 0 UID: 0 PID: 10315 Comm: syz.1.1732 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 Call Trace: 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 __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:4847 [inline] path_openat+0x1748/0x20f0 fs/namei.c:5010 do_file_open+0x23e/0x4a0 fs/namei.c:5039 do_sys_openat2+0x115/0x200 fs/open.c:1442 do_sys_open fs/open.c:1448 [inline] __do_sys_openat fs/open.c:1788 [inline] __se_sys_openat fs/open.c:1783 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1783 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: 0033:0x7fc70d79f559 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:00007fc70e5dd028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fc70da25fa0 RCX: 00007fc70d79f559 RDX: 0000000000007a05 RSI: 00002000000000c0 RDI: ffffffffffffff9c RBP: 00007fc70d836b20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000001700 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc70da26038 R14: 00007fc70da25fa0 R15: 00007ffe3cef6b98