======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.3.1255/10863 is trying to acquire lock:
ffffffff8ddf69d0 (gadget_subsys.su_mutex){+.+.}-{3:3}, at: uvcg_extension_bm_controls_show+0x78/0x2a0 drivers/usb/gadget/function/uvc_configfs.c:1096

but task is already holding lock:
ffff88802ec60478 (&p->frag_sem){++++}-{3:3}, at: fill_read_buffer fs/configfs/file.c:66 [inline]
ffff88802ec60478 (&p->frag_sem){++++}-{3:3}, at: configfs_read_iter+0x1a5/0x570 fs/configfs/file.c:88

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&p->frag_sem){++++}-{3:3}:
       down_write_killable+0xa7/0x230 kernel/locking/rwsem.c:1584
       configfs_rmdir+0x3e4/0x980 fs/configfs/dir.c:1534
       vfs_rmdir+0x352/0x4b0 fs/namei.c:4251
       do_rmdir+0x29f/0x590 fs/namei.c:4310
       __do_sys_unlinkat fs/namei.c:4488 [inline]
       __se_sys_unlinkat fs/namei.c:4482 [inline]
       __x64_sys_unlinkat+0xc4/0xe0 fs/namei.c:4482
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #2 (&sb->s_type->i_mutex_key#23){++++}-{3:3}:
       down_write+0x97/0x200 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:804 [inline]
       configfs_depend_item_unlocked+0x157/0x430 fs/configfs/dir.c:1255
       usbg_make_tpg+0x1f7/0x580 drivers/usb/gadget/function/f_tcm.c:1341
       target_fabric_make_tpg+0xa4/0x6d0 drivers/target/target_core_fabric_configfs.c:939
       configfs_mkdir+0x515/0x9e0 fs/configfs/dir.c:1360
       vfs_mkdir+0x2a5/0x470 fs/namei.c:4168
       do_mkdirat+0x1dc/0x450 fs/namei.c:4191
       __do_sys_mkdirat fs/namei.c:4206 [inline]
       __se_sys_mkdirat fs/namei.c:4204 [inline]
       __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4204
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (&opts->dep_lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x135/0xc80 kernel/locking/mutex.c:747
       tcm_set_name+0x2a/0x90 drivers/usb/gadget/function/f_tcm.c:2317
       function_make+0x199/0x350 drivers/usb/gadget/configfs.c:635
       configfs_mkdir+0x515/0x9e0 fs/configfs/dir.c:1360
       vfs_mkdir+0x2a5/0x470 fs/namei.c:4168
       do_mkdirat+0x1dc/0x450 fs/namei.c:4191
       __do_sys_mkdirat fs/namei.c:4206 [inline]
       __se_sys_mkdirat fs/namei.c:4204 [inline]
       __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4204
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (gadget_subsys.su_mutex){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x37ef/0x7d80 kernel/locking/lockdep.c:5137
       lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x135/0xc80 kernel/locking/mutex.c:747
       uvcg_extension_bm_controls_show+0x78/0x2a0 drivers/usb/gadget/function/uvc_configfs.c:1096
       fill_read_buffer fs/configfs/file.c:68 [inline]
       configfs_read_iter+0x29d/0x570 fs/configfs/file.c:88
       __kernel_read+0x2e5/0x730 fs/read_write.c:428
       integrity_kernel_read+0x8a/0xd0 security/integrity/iint.c:221
       ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
       ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
       ima_calc_file_hash+0xb1f/0x1960 security/integrity/ima/ima_crypto.c:573
       ima_collect_measurement+0x4d4/0xa30 security/integrity/ima/ima_api.c:290
       process_measurement+0x123a/0x1d50 security/integrity/ima/ima_main.c:370
       ima_file_check+0xcc/0x110 security/integrity/ima/ima_main.c:568
       do_open fs/namei.c:3685 [inline]
       path_openat+0x2910/0x3270 fs/namei.c:3844
       do_filp_open+0x1f2/0x430 fs/namei.c:3871
       do_sys_openat2+0x134/0x1d0 fs/open.c:1422
       do_sys_open fs/open.c:1437 [inline]
       __do_sys_openat fs/open.c:1453 [inline]
       __se_sys_openat fs/open.c:1448 [inline]
       __x64_sys_openat+0x139/0x160 fs/open.c:1448
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:
  gadget_subsys.su_mutex --> &sb->s_type->i_mutex_key#23 --> &p->frag_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(&p->frag_sem);
                               lock(&sb->s_type->i_mutex_key#23);
                               lock(&p->frag_sem);
  lock(gadget_subsys.su_mutex);

 *** DEADLOCK ***

3 locks held by syz.3.1255/10863:
 #0: ffff888076e31c10 (&iint_mutex_key[depth]){+.+.}-{3:3}, at: process_measurement+0x739/0x1d50 security/integrity/ima/ima_main.c:275
 #1: ffff888078e7da88 (&buffer->mutex){+.+.}-{3:3}, at: configfs_read_iter+0x72/0x570 fs/configfs/file.c:86
 #2: ffff88802ec60478 (&p->frag_sem){++++}-{3:3}, at: fill_read_buffer fs/configfs/file.c:66 [inline]
 #2: ffff88802ec60478 (&p->frag_sem){++++}-{3:3}, at: configfs_read_iter+0x1a5/0x570 fs/configfs/file.c:88

stack backtrace:
CPU: 1 PID: 10863 Comm: syz.3.1255 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x37ef/0x7d80 kernel/locking/lockdep.c:5137
 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x135/0xc80 kernel/locking/mutex.c:747
 uvcg_extension_bm_controls_show+0x78/0x2a0 drivers/usb/gadget/function/uvc_configfs.c:1096
 fill_read_buffer fs/configfs/file.c:68 [inline]
 configfs_read_iter+0x29d/0x570 fs/configfs/file.c:88
 __kernel_read+0x2e5/0x730 fs/read_write.c:428
 integrity_kernel_read+0x8a/0xd0 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0xb1f/0x1960 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x4d4/0xa30 security/integrity/ima/ima_api.c:290
 process_measurement+0x123a/0x1d50 security/integrity/ima/ima_main.c:370
 ima_file_check+0xcc/0x110 security/integrity/ima/ima_main.c:568
 do_open fs/namei.c:3685 [inline]
 path_openat+0x2910/0x3270 fs/namei.c:3844
 do_filp_open+0x1f2/0x430 fs/namei.c:3871
 do_sys_openat2+0x134/0x1d0 fs/open.c:1422
 do_sys_open fs/open.c:1437 [inline]
 __do_sys_openat fs/open.c:1453 [inline]
 __se_sys_openat fs/open.c:1448 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1448
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f121279e0d9
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:00007f12135e8028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1212a25fa0 RCX: 00007f121279e0d9
RDX: 0000000000000000 RSI: 00002000000003c0 RDI: ffffffffffffff9c
RBP: 00007f1212835024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1212a26038 R14: 00007f1212a25fa0 R15: 00007ffe12a85048
 </TASK>
netlink: 'syz.3.1255': attribute type 1 has an invalid length.