================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:625 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x15c5/0x1bd0 kernel/locking/mutex.c:821 Read of size 8 at addr ffff88801fafc858 by task syz-executor/5596 CPU: 1 UID: 0 PID: 5596 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 __mutex_lock_common kernel/locking/mutex.c:625 [inline] __mutex_lock+0x15c5/0x1bd0 kernel/locking/mutex.c:821 ep_open+0x4c/0x2c0 drivers/usb/gadget/legacy/inode.c:832 do_dentry_open+0x6ab/0x14d0 fs/open.c:996 vfs_open+0x82/0x3f0 fs/open.c:1101 do_open fs/namei.c:4837 [inline] path_openat+0x19fa/0x2440 fs/namei.c:5000 do_file_open+0x20e/0x430 fs/namei.c:5029 do_sys_openat2+0x10f/0x1e0 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+0x12d/0x210 fs/open.c:1434 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f45e695e98e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007fff240d6d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00005555915a3500 RCX: 00007f45e695e98e RDX: 0000000000000000 RSI: 00007fff240d6f00 RDI: ffffffffffffff9c RBP: 00007fff240d6f00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff240d7ff0 R13: 00007f45e6a3448b R14: 00005555915a34e8 R15: 0000000000000006 Allocated by task 8601: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2f8/0x6d0 mm/slub.c:5563 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] activate_ep_files drivers/usb/gadget/legacy/inode.c:1611 [inline] gadgetfs_bind+0x582/0x890 drivers/usb/gadget/legacy/inode.c:1702 gadget_bind_driver+0x28c/0xbf0 drivers/usb/gadget/udc/core.c:1662 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __driver_attach+0x21f/0x5b0 drivers/base/dd.c:1292 bus_for_each_dev+0x13e/0x1d0 drivers/base/bus.c:383 bus_add_driver+0x305/0x5b0 drivers/base/bus.c:763 driver_register+0x1e2/0x360 drivers/base/driver.c:174 usb_gadget_register_driver_owner+0x132/0x210 drivers/usb/gadget/udc/core.c:1752 dev_config+0xdce/0x1610 drivers/usb/gadget/legacy/inode.c:1893 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 8600: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6508 [inline] kfree+0x22b/0x6d0 mm/slub.c:6801 put_ep drivers/usb/gadget/legacy/inode.c:225 [inline] put_ep+0x117/0x150 drivers/usb/gadget/legacy/inode.c:217 destroy_ep_files+0x163/0x420 drivers/usb/gadget/legacy/inode.c:1592 gadgetfs_unbind+0x139/0x260 drivers/usb/gadget/legacy/inode.c:1665 gadget_unbind_driver+0x20c/0x4f0 drivers/usb/gadget/udc/core.c:1724 device_remove+0xcb/0x180 drivers/base/dd.c:616 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372 driver_detach+0xd8/0x1b0 drivers/base/dd.c:1435 bus_remove_driver+0x13b/0x2e0 drivers/base/bus.c:832 driver_unregister+0x76/0xb0 drivers/base/driver.c:202 usb_gadget_unregister_driver+0x49/0x70 drivers/usb/gadget/udc/core.c:1784 dev_release+0x132/0x1b0 drivers/usb/gadget/legacy/inode.c:1207 __fput+0x3ff/0xb50 fs/file_table.c:512 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2ae0 kernel/exit.c:1011 do_group_exit+0xd5/0x2a0 kernel/exit.c:1154 get_signal+0x1ec7/0x21e0 kernel/signal.c:3051 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop kernel/entry/common.c:101 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline] irqentry_exit+0x402/0xa10 kernel/entry/common.c:165 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 The buggy address belongs to the object at ffff88801fafc800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 88 bytes inside of freed 512-byte region [ffff88801fafc800, ffff88801fafca00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1fafc head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801c02fc80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801c02fc80 dead000000000100 dead000000000122 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2, tgid 2 (kthreadd), ts 1782608215 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x110d/0x35d0 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436 alloc_pages_mpol+0x201/0x550 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3345 [inline] allocate_slab mm/slub.c:3462 [inline] new_slab+0x407/0x6e0 mm/slub.c:3513 ___slab_alloc+0x2a1/0x810 mm/slub.c:4568 slab_alloc_node mm/slub.c:4987 [inline] __do_kmalloc_node mm/slub.c:5413 [inline] __kmalloc_flags_noprof+0x470/0x8e0 mm/slub.c:5602 _kmalloc_flags_noprof mm/slab.h:55 [inline] __alloc_empty_sheaf mm/slub.c:2822 [inline] alloc_empty_sheaf mm/slub.c:2842 [inline] __pcs_replace_empty_main+0x3fa/0x650 mm/slub.c:4769 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] __do_kmalloc_node mm/slub.c:5413 [inline] __kmalloc_flags_noprof+0x6a9/0x8e0 mm/slub.c:5602 _kmalloc_flags_noprof mm/slab.h:55 [inline] __alloc_empty_sheaf mm/slub.c:2822 [inline] alloc_empty_sheaf mm/slub.c:2842 [inline] __pcs_replace_empty_main+0x3fa/0x650 mm/slub.c:4769 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] kmem_cache_alloc_node_noprof+0x4f2/0x6e0 mm/slub.c:5068 alloc_task_struct_node kernel/fork.c:188 [inline] dup_task_struct kernel/fork.c:922 [inline] copy_process+0x6a2/0x8370 kernel/fork.c:2133 kernel_clone+0x176/0x9d0 kernel/fork.c:2766 kernel_thread+0xdb/0x120 kernel/fork.c:2827 create_kthread kernel/kthread.c:459 [inline] kthreadd+0x498/0x7a0 kernel/kthread.c:817 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 page_owner free stack trace missing Memory state around the buggy address: ffff88801fafc700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801fafc780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801fafc800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801fafc880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801fafc900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================