================================================================== BUG: KASAN: slab-use-after-free in list_empty include/linux/list.h:373 [inline] BUG: KASAN: slab-use-after-free in driver_deferred_probe_del+0x78/0x240 drivers/base/dd.c:148 Read of size 8 at addr ffff8881163998a8 by task syz.1.21/412 CPU: 0 UID: 0 PID: 412 Comm: syz.1.21 Not tainted syzkaller #0 f10dc98c92500eb86b2a5bf5b389293121b4eb86 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 print_address_description+0x71/0x210 mm/kasan/report.c:377 print_report+0x4a/0x70 mm/kasan/report.c:481 kasan_report+0x162/0x1a0 mm/kasan/report.c:594 __asan_report_load8_noabort+0x18/0x20 mm/kasan/report_generic.c:381 list_empty include/linux/list.h:373 [inline] driver_deferred_probe_del+0x78/0x240 drivers/base/dd.c:148 device_del+0x593/0xcf0 drivers/base/core.c:3883 usb_del_gadget+0x18f/0x200 drivers/usb/gadget/udc/core.c:1550 usb_del_gadget_udc+0x19/0x30 drivers/usb/gadget/udc/core.c:1566 dummy_udc_remove+0x5c/0x70 drivers/usb/gadget/udc/dummy_hcd.c:1123 platform_remove+0x81/0xb0 drivers/base/platform.c:1424 device_remove drivers/base/dd.c:567 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4ad/0x830 drivers/base/dd.c:1295 device_driver_detach+0x3f/0x50 drivers/base/dd.c:1331 unbind_store+0x1ab/0x1f0 drivers/base/bus.c:244 drv_attr_store+0x91/0xb0 drivers/base/bus.c:125 sysfs_kf_write+0x141/0x160 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x762/0xfd0 fs/read_write.c:684 ksys_write+0x145/0x260 fs/read_write.c:737 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x7f/0x90 fs/read_write.c:746 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fc02339de99 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:00007fff06a59d78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fc023625fa0 RCX: 00007fc02339de99 RDX: 000000000000000b RSI: 0000200000000400 RDI: 0000000000000004 RBP: 00007fc023433eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc023625fac R14: 00007fc023625fa0 R15: 00007fc023625fa0 Allocated by task 401: kasan_save_stack mm/kasan/common.c:49 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:70 kasan_save_alloc_info+0x3a/0x50 mm/kasan/generic.c:565 poison_kmalloc_redzone mm/kasan/common.c:379 [inline] __kasan_kmalloc+0x96/0xb0 mm/kasan/common.c:396 kasan_kmalloc include/linux/kasan.h:261 [inline] __kmalloc_cache_noprof+0x23c/0x470 mm/slub.c:4426 kmalloc_noprof include/linux/slab.h:881 [inline] kzalloc_noprof include/linux/slab.h:1017 [inline] device_private_init drivers/base/core.c:3537 [inline] device_add+0xc1/0xbf0 drivers/base/core.c:3588 usb_add_gadget+0x3e9/0x6e0 drivers/usb/gadget/udc/core.c:1427 usb_add_gadget_udc_release drivers/usb/gadget/udc/core.c:1477 [inline] usb_add_gadget_udc+0x11e/0x160 drivers/usb/gadget/udc/core.c:1524 dummy_udc_probe+0x6ea/0x7f0 drivers/usb/gadget/udc/dummy_hcd.c:1102 platform_probe+0x17a/0x200 drivers/base/platform.c:1404 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2e1/0x8b0 drivers/base/dd.c:657 __driver_probe_device+0x193/0x280 drivers/base/dd.c:799 device_driver_attach+0xdb/0x1f0 drivers/base/dd.c:1126 bind_store+0x1dc/0x230 drivers/base/bus.c:267 drv_attr_store+0x91/0xb0 drivers/base/bus.c:125 sysfs_kf_write+0x141/0x160 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x762/0xfd0 fs/read_write.c:684 ksys_write+0x145/0x260 fs/read_write.c:737 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x7f/0x90 fs/read_write.c:746 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 412: kasan_save_stack mm/kasan/common.c:49 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:70 kasan_save_free_info+0x44/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:249 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:266 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2445 [inline] slab_free mm/slub.c:4714 [inline] kfree+0x158/0x440 mm/slub.c:4875 device_release+0xb6/0x1e0 drivers/base/core.c:2572 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1a7/0x2a0 lib/kobject.c:737 put_device+0x23/0x40 drivers/base/core.c:3800 klist_devices_put+0x3c/0x60 drivers/base/bus.c:817 klist_put lib/klist.c:221 [inline] klist_del+0xf5/0x120 lib/klist.c:230 bus_remove_device+0x33f/0x370 drivers/base/bus.c:572 device_del+0x583/0xcf0 drivers/base/core.c:3881 usb_del_gadget+0x18f/0x200 drivers/usb/gadget/udc/core.c:1550 usb_del_gadget_udc+0x19/0x30 drivers/usb/gadget/udc/core.c:1566 dummy_udc_remove+0x5c/0x70 drivers/usb/gadget/udc/dummy_hcd.c:1123 platform_remove+0x81/0xb0 drivers/base/platform.c:1424 device_remove drivers/base/dd.c:567 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4ad/0x830 drivers/base/dd.c:1295 device_driver_detach+0x3f/0x50 drivers/base/dd.c:1331 unbind_store+0x1ab/0x1f0 drivers/base/bus.c:244 drv_attr_store+0x91/0xb0 drivers/base/bus.c:125 sysfs_kf_write+0x141/0x160 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x762/0xfd0 fs/read_write.c:684 ksys_write+0x145/0x260 fs/read_write.c:737 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x7f/0x90 fs/read_write.c:746 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff888116399800 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 168 bytes inside of freed 256-byte region [ffff888116399800, ffff888116399900) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x116398 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x4000000000000040(head|zone=1) page_type: f5(slab) raw: 4000000000000040 ffff888100041b40 0000000000000000 0000000000000001 raw: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 4000000000000040 ffff888100041b40 0000000000000000 0000000000000001 head: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 4000000000000001 ffffea000458e601 ffffffffffffffff 0000000000000000 head: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 123, tgid 123 (udevd), ts 6582133114, free_ts 0 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook+0x37d/0x3b0 mm/page_alloc.c:1863 prep_new_page+0x2d/0x180 mm/page_alloc.c:1871 get_page_from_freelist+0x4aea/0x4ba0 mm/page_alloc.c:3948 __alloc_pages_noprof+0x35a/0x7e0 mm/page_alloc.c:5315 alloc_slab_page+0x6b/0x1e0 mm/slub.c:-1 allocate_slab+0x69/0x430 mm/slub.c:2687 new_slab mm/slub.c:2741 [inline] ___slab_alloc+0x591/0x8c0 mm/slub.c:3934 __slab_alloc mm/slub.c:4025 [inline] __slab_alloc_node mm/slub.c:4078 [inline] slab_alloc_node mm/slub.c:4239 [inline] __kmalloc_cache_noprof+0x2cd/0x470 mm/slub.c:4421 kmalloc_noprof include/linux/slab.h:881 [inline] inode_doinit_use_xattr+0x6a/0x550 security/selinux/hooks.c:1375 inode_doinit_with_dentry+0x9b1/0xde0 security/selinux/hooks.c:1569 selinux_d_instantiate+0x2b/0x40 security/selinux/hooks.c:6361 security_d_instantiate+0xb8/0xf0 security/security.c:4068 d_splice_alias+0x71/0x3a0 fs/dcache.c:2949 kernfs_iop_lookup+0x2c6/0x320 fs/kernfs/dir.c:1233 __lookup_slow+0x2e5/0x420 fs/namei.c:1740 lookup_slow+0x57/0x80 fs/namei.c:1757 page_owner free stack trace missing Memory state around the buggy address: ffff888116399780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888116399800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888116399880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888116399900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888116399980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 412 at lib/refcount.c:28 refcount_warn_saturate+0x119/0x1c0 lib/refcount.c:28 Modules linked in: CPU: 1 UID: 0 PID: 412 Comm: syz.1.21 Tainted: G B syzkaller #0 f10dc98c92500eb86b2a5bf5b389293121b4eb86 Tainted: [B]=BAD_PAGE Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:refcount_warn_saturate+0x119/0x1c0 lib/refcount.c:28 Code: 05 01 48 c7 c7 00 eb 51 86 e8 43 8f 55 fe 0f 0b eb da e8 ea b8 d8 fe c6 05 47 87 36 05 01 48 c7 c7 60 eb 51 86 e8 27 8f 55 fe <0f> 0b eb be e8 ce b8 d8 fe c6 05 28 87 36 05 01 48 c7 c7 a0 ea 51 RSP: 0018:ffffc90001aefa48 EFLAGS: 00010246 RAX: c58799a980276200 RBX: 0000000000000003 RCX: ffff8881186b5f00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002 RBP: ffffc90001aefa58 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff0e9f34c R12: 0000000000000000 R13: ffff888104304d34 R14: ffff888104304d30 R15: ffff888104304d30 FS: 0000555563f8b500(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b34563fff CR3: 00000001185f8000 CR4: 00000000003526b0 Call Trace: __refcount_sub_and_test include/linux/refcount.h:400 [inline] __refcount_dec_and_test include/linux/refcount.h:432 [inline] refcount_dec_and_test include/linux/refcount.h:450 [inline] kref_put include/linux/kref.h:64 [inline] kobject_put+0x25a/0x2a0 lib/kobject.c:737 put_device+0x23/0x40 drivers/base/core.c:3800 usb_put_gadget include/linux/usb/gadget.h:512 [inline] usb_del_gadget_udc+0x25/0x30 drivers/usb/gadget/udc/core.c:1567 dummy_udc_remove+0x5c/0x70 drivers/usb/gadget/udc/dummy_hcd.c:1123 platform_remove+0x81/0xb0 drivers/base/platform.c:1424 device_remove drivers/base/dd.c:567 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4ad/0x830 drivers/base/dd.c:1295 device_driver_detach+0x3f/0x50 drivers/base/dd.c:1331 unbind_store+0x1ab/0x1f0 drivers/base/bus.c:244 drv_attr_store+0x91/0xb0 drivers/base/bus.c:125 sysfs_kf_write+0x141/0x160 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x762/0xfd0 fs/read_write.c:684 ksys_write+0x145/0x260 fs/read_write.c:737 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x7f/0x90 fs/read_write.c:746 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fc02339de99 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:00007fff06a59d78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fc023625fa0 RCX: 00007fc02339de99 RDX: 000000000000000b RSI: 0000200000000400 RDI: 0000000000000004 RBP: 00007fc023433eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc023625fac R14: 00007fc023625fa0 R15: 00007fc023625fa0 ---[ end trace 0000000000000000 ]---