====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.451/6327 is trying to acquire lock: ffff800016f37e90 (gadget_subsys.su_mutex){+.+.}-{3:3}, at: configfs_rmdir+0x564/0x850 fs/configfs/dir.c:1556 but task is already holding lock: ffff0000e1767900 (&sb->s_type->i_mutex_key#20){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] ffff0000e1767900 (&sb->s_type->i_mutex_key#20){++++}-{3:3}, at: vfs_rmdir+0x10c/0x438 fs/namei.c:4231 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sb->s_type->i_mutex_key#20){++++}-{3:3}: down_write+0x5c/0x88 kernel/locking/rwsem.c:1573 inode_lock include/linux/fs.h:764 [inline] configfs_depend_item_unlocked+0x128/0x41c fs/configfs/dir.c:1255 usbg_make_tpg+0x1d0/0x4cc drivers/usb/gadget/function/f_tcm.c:1365 target_fabric_make_tpg+0x98/0x518 drivers/target/target_core_fabric_configfs.c:913 configfs_mkdir+0x3e0/0x884 fs/configfs/dir.c:1360 vfs_mkdir+0x314/0x4d8 fs/namei.c:4157 do_mkdirat+0x1b8/0x3ec fs/namei.c:4182 __do_sys_mkdirat fs/namei.c:4197 [inline] __se_sys_mkdirat fs/namei.c:4195 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4195 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #1 (&opts->dep_lock){+.+.}-{3:3}: __mutex_lock_common+0x1a0/0x1f3c kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 tcm_set_name+0x30/0xa4 drivers/usb/gadget/function/f_tcm.c:2348 function_make+0x184/0x2f8 drivers/usb/gadget/configfs.c:625 configfs_mkdir+0x3e0/0x884 fs/configfs/dir.c:1360 vfs_mkdir+0x314/0x4d8 fs/namei.c:4157 do_mkdirat+0x1b8/0x3ec fs/namei.c:4182 __do_sys_mkdirat fs/namei.c:4197 [inline] __se_sys_mkdirat fs/namei.c:4195 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4195 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #0 (gadget_subsys.su_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3830 [inline] __lock_acquire+0x2808/0x6634 kernel/locking/lockdep.c:5063 lock_acquire+0x20c/0x638 kernel/locking/lockdep.c:5676 __mutex_lock_common+0x1a0/0x1f3c kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 configfs_rmdir+0x564/0x850 fs/configfs/dir.c:1556 vfs_rmdir+0x304/0x438 fs/namei.c:4242 do_rmdir+0x244/0x524 fs/namei.c:4303 __do_sys_unlinkat fs/namei.c:4483 [inline] __se_sys_unlinkat fs/namei.c:4477 [inline] __arm64_sys_unlinkat+0xcc/0xfc fs/namei.c:4477 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 other info that might help us debug this: Chain exists of: gadget_subsys.su_mutex --> &opts->dep_lock --> &sb->s_type->i_mutex_key#20 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#20); lock(&opts->dep_lock); lock(&sb->s_type->i_mutex_key#20); lock(gadget_subsys.su_mutex); *** DEADLOCK *** 3 locks held by syz.0.451/6327: #0: ffff0000c7068460 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000d83cc150 (&default_group_class[depth - 1]#2/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:799 [inline] #1: ffff0000d83cc150 (&default_group_class[depth - 1]#2/1){+.+.}-{3:3}, at: do_rmdir+0x180/0x524 fs/namei.c:4290 #2: ffff0000e1767900 (&sb->s_type->i_mutex_key#20){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #2: ffff0000e1767900 (&sb->s_type->i_mutex_key#20){++++}-{3:3}, at: vfs_rmdir+0x10c/0x438 fs/namei.c:4231 stack backtrace: CPU: 1 PID: 6327 Comm: syz.0.451 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026 Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 print_circular_bug+0x148/0x1b0 kernel/locking/lockdep.c:2048 check_noncircular+0x264/0x2f8 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3830 [inline] __lock_acquire+0x2808/0x6634 kernel/locking/lockdep.c:5063 lock_acquire+0x20c/0x638 kernel/locking/lockdep.c:5676 __mutex_lock_common+0x1a0/0x1f3c kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 configfs_rmdir+0x564/0x850 fs/configfs/dir.c:1556 vfs_rmdir+0x304/0x438 fs/namei.c:4242 do_rmdir+0x244/0x524 fs/namei.c:4303 __do_sys_unlinkat fs/namei.c:4483 [inline] __se_sys_unlinkat fs/namei.c:4477 [inline] __arm64_sys_unlinkat+0xcc/0xfc fs/namei.c:4477 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 printk: console [ttyGS0] disabled