==================================================================
BUG: KASAN: slab-use-after-free in __raw_spin_lock_irq include/linux/spinlock_api_smp.h:165 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_irq+0x58/0x70 kernel/locking/spinlock.c:189
Read of size 1 at addr ffff0000c9fb1818 by task syz.0.18/4920

CPU: 0 UID: 0 PID: 4920 Comm: syz.0.18 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 print_address_description+0xb0/0x238 mm/kasan/report.c:378
 print_report+0x68/0x84 mm/kasan/report.c:482
 kasan_report+0x8c/0xc4 mm/kasan/report.c:595
 __kasan_check_byte+0x3c/0x54 mm/kasan/common.c:585
 kasan_check_byte include/linux/kasan.h:402 [inline]
 lock_acquire+0xa4/0x320 kernel/locking/lockdep.c:5916
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:165 [inline]
 _raw_spin_lock_irq+0x58/0x70 kernel/locking/spinlock.c:189
 spin_lock_irq include/linux/spinlock.h:377 [inline]
 gadget_dev_open+0x50/0x1c4 drivers/usb/gadget/legacy/inode.c:1929
 do_dentry_open+0x5c4/0xfbc fs/open.c:996
 vfs_open+0x44/0x2dc fs/open.c:1101
 do_open fs/namei.c:4866 [inline]
 path_openat+0x1084/0x18f0 fs/namei.c:5029
 do_file_open+0x1c8/0x2e8 fs/namei.c:5058
 do_sys_openat2+0x114/0x1e8 fs/open.c:1417
 do_sys_open+0xb0/0xe0 fs/open.c:1423
 __do_sys_openat fs/open.c:1439 [inline]
 __se_sys_openat fs/open.c:1434 [inline]
 __arm64_sys_openat+0xa8/0xc4 fs/open.c:1434
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:796
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606

Allocated by task 4822:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:78
 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:570
 poison_kmalloc_redzone mm/kasan/common.c:409 [inline]
 __kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:426
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x2f4/0x5fc mm/slub.c:5563
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 dev_new drivers/usb/gadget/legacy/inode.c:176 [inline]
 gadgetfs_fill_super+0x19c/0x370 drivers/usb/gadget/legacy/inode.c:2064
 vfs_get_super+0xb8/0x148 fs/super.c:1390
 get_tree_single+0x30/0x40 fs/super.c:1417
 gadgetfs_get_tree+0x28/0x38 drivers/usb/gadget/legacy/inode.c:2095
 vfs_get_tree+0x90/0x28c fs/super.c:1932
 fc_mount+0x24/0xac fs/namespace.c:1278
 do_new_mount_fc fs/namespace.c:3885 [inline]
 do_new_mount+0x2a4/0x538 fs/namespace.c:3961
 path_mount+0x5f0/0xa88 fs/namespace.c:4312
 do_mount+0xe8/0x148 fs/namespace.c:4325
 __do_sys_mount fs/namespace.c:4543 [inline]
 __se_sys_mount fs/namespace.c:4520 [inline]
 __arm64_sys_mount+0x33c/0x388 fs/namespace.c:4520
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:796
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606

Freed by task 4918:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:78
 kasan_save_free_info+0x54/0x6c mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:264 [inline]
 __kasan_slab_free+0x74/0xa4 mm/kasan/common.c:296
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2748 [inline]
 slab_free mm/slub.c:6509 [inline]
 kfree+0x188/0x658 mm/slub.c:6802
 put_dev+0x8c/0xf8 drivers/usb/gadget/legacy/inode.c:169
 dev_release+0x100/0x15c drivers/usb/gadget/legacy/inode.c:1224
 __fput+0x338/0x74c fs/file_table.c:512
 ____fput+0x20/0x30 fs/file_table.c:541
 task_work_run+0x1cc/0x25c kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x58c/0x1a74 kernel/exit.c:986
 do_group_exit+0x198/0x238 kernel/exit.c:1129
 get_signal+0xfb0/0x1094 kernel/signal.c:3112
 arch_do_signal_or_restart+0x288/0x444c arch/arm64/kernel/signal.c:1671
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x70/0x17c kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 arm64_syscall_exit_to_user_mode arch/arm64/kernel/entry-common.c:146 [inline]
 el0_svc+0x12c/0x1d8 arch/arm64/kernel/entry-common.c:797
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606

The buggy address belongs to the object at ffff0000c9fb1800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 24 bytes inside of
 freed 1024-byte region [ffff0000c9fb1800, ffff0000c9fb1c00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x109fb0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x5ffc00000000040(head|node=0|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 05ffc00000000040 ffff0000c0001dc0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 05ffc00000000040 ffff0000c0001dc0 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 05ffc00000000003 fffffdffc327ec01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000c9fb1700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000c9fb1780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff0000c9fb1800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff0000c9fb1880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000c9fb1900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in kernel/locking/qspinlock.h:68:9
index 12985 is out of range for type 'unsigned long[8]'
CPU: 0 UID: 0 PID: 4920 Comm: syz.0.18 Tainted: G    B               syzkaller #0 PREEMPT 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 dump_stack+0x1c/0x28 lib/dump_stack.c:129
 ubsan_epilogue+0x14/0x48 lib/ubsan.c:233
 __ubsan_handle_out_of_bounds+0xd0/0xf8 lib/ubsan.c:455
 decode_tail kernel/locking/qspinlock.h:68 [inline]
 queued_spin_lock_slowpath+0x834/0xb5c kernel/locking/qspinlock.c:307
 queued_spin_lock include/asm-generic/qspinlock.h:115 [inline]
 do_raw_spin_lock+0x21c/0x2d0 kernel/locking/spinlock_debug.c:116
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:166 [inline]
 _raw_spin_lock_irq+0x60/0x70 kernel/locking/spinlock.c:189
 spin_lock_irq include/linux/spinlock.h:377 [inline]
 gadget_dev_open+0x50/0x1c4 drivers/usb/gadget/legacy/inode.c:1929
 do_dentry_open+0x5c4/0xfbc fs/open.c:996
 vfs_open+0x44/0x2dc fs/open.c:1101
 do_open fs/namei.c:4866 [inline]
 path_openat+0x1084/0x18f0 fs/namei.c:5029
 do_file_open+0x1c8/0x2e8 fs/namei.c:5058
 do_sys_openat2+0x114/0x1e8 fs/open.c:1417
 do_sys_open+0xb0/0xe0 fs/open.c:1423
 __do_sys_openat fs/open.c:1439 [inline]
 __se_sys_openat fs/open.c:1434 [inline]
 __arm64_sys_openat+0xa8/0xc4 fs/open.c:1434
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:796
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606
---[ end trace ]---