LUN: removable file: (no medium) ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.9.753/10122 is trying to acquire lock: ffff88807cf15060 (&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: ffff888052432920 (&common->filesem){++++}-{4:4}, at: fsg_store_file+0x163/0x400 drivers/usb/gadget/function/storage_common.c:452 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&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 -> #1 (&p->frag_sem){++++}-{4:4}: down_read+0x4a/0x330 kernel/locking/rwsem.c:1574 __configfs_open_file+0xd8/0x7d0 fs/configfs/file.c:304 do_dentry_open+0x816/0x1380 fs/open.c:996 vfs_open+0x3b/0x340 fs/open.c:1101 dentry_open+0x61/0xa0 fs/open.c:1124 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+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: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+0x19d/0x1550 kernel/locking/mutex.c:821 process_measurement+0x7d0/0x1c10 security/integrity/ima/ima_main.c:319 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 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 other info that might help us debug this: Chain exists of: &ima_iint_mutex_key[depth] --> &p->frag_sem --> &common->filesem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&common->filesem); lock(&p->frag_sem); lock(&common->filesem); lock(&ima_iint_mutex_key[depth]); *** DEADLOCK *** locks held by syz.9.753/10122: 5, last CPU#0: #0: ffff88807932a7f0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259 #1: ffff88801d306460 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2753 [inline] #1: ffff88801d306460 (sb_writers#12){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #2: ffff888054669480 (&buffer->mutex#2){+.+.}-{4:4}, at: configfs_write_iter+0x7e/0x430 fs/configfs/file.c:226 #3: ffff888058f38670 (&p->frag_sem){++++}-{4:4}, at: flush_write_buffer fs/configfs/file.c:205 [inline] #3: ffff888058f38670 (&p->frag_sem){++++}-{4:4}, at: configfs_write_iter+0x238/0x430 fs/configfs/file.c:229 #4: ffff888052432920 (&common->filesem){++++}-{4:4}, at: fsg_store_file+0x163/0x400 drivers/usb/gadget/function/storage_common.c:452 stack backtrace: CPU: 0 UID: 0 PID: 10122 Comm: syz.9.753 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026 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+0x19d/0x1550 kernel/locking/mutex.c:821 process_measurement+0x7d0/0x1c10 security/integrity/ima/ima_main.c:319 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 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 RIP: 0033:0x7efdc6f9e159 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:00007efdc7e5b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007efdc7225fa0 RCX: 00007efdc6f9e159 RDX: 0000000000000005 RSI: 00002000000003c0 RDI: 0000000000000004 RBP: 00007efdc703506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efdc7226038 R14: 00007efdc7225fa0 R15: 00007ffebb14e798