================================================================== BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x92/0x190 lib/list_debug.c:62 Read of size 8 at addr ffff88801e6fb780 by task kworker/u9:0/8745 CPU: 1 UID: 0 PID: 8745 Comm: kworker/u9:0 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: hci1 hci_rx_work Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 __list_del_entry_valid_or_report+0x92/0x190 lib/list_debug.c:62 __list_del_entry_valid include/linux/list.h:132 [inline] __list_del_entry include/linux/list.h:223 [inline] list_del_init include/linux/list.h:295 [inline] bt_accept_unlink+0x39/0x260 net/bluetooth/af_bluetooth.c:259 l2cap_sock_teardown_cb+0x17e/0x490 net/bluetooth/l2cap_sock.c:1643 l2cap_chan_del+0xb5/0x610 net/bluetooth/l2cap_core.c:656 l2cap_conn_del+0x33d/0x570 net/bluetooth/l2cap_core.c:1802 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline] hci_disconn_complete_evt+0x501/0x950 net/bluetooth/hci_event.c:3465 hci_event_func net/bluetooth/hci_event.c:7796 [inline] hci_event_packet+0x6ab/0xef0 net/bluetooth/hci_event.c:7847 hci_rx_work+0x3ee/0x1040 net/bluetooth/hci_core.c:4077 process_one_work+0xa31/0x1980 kernel/workqueue.c:3320 process_scheduled_works kernel/workqueue.c:3423 [inline] worker_thread+0xba8/0x11e0 kernel/workqueue.c:3509 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 10946: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5308 [inline] __kmalloc_noprof+0x3e7/0x7b0 mm/slub.c:5320 kmalloc_noprof include/linux/slab.h:954 [inline] sk_prot_alloc+0xe7/0x210 net/core/sock.c:2247 sk_alloc+0x3a/0x390 net/core/sock.c:2303 bt_sock_alloc+0x3b/0x310 net/bluetooth/af_bluetooth.c:151 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1934 [inline] l2cap_sock_create+0x147/0x330 net/bluetooth/l2cap_sock.c:1976 bt_sock_create+0x163/0x240 net/bluetooth/af_bluetooth.c:135 __sock_create+0x4e3/0x960 net/socket.c:1679 sock_create net/socket.c:1737 [inline] __sys_socket_create net/socket.c:1774 [inline] __sys_socket+0xd9/0x330 net/socket.c:1821 __do_sys_socket net/socket.c:1835 [inline] __se_sys_socket net/socket.c:1833 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1833 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 10946: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2700 [inline] slab_free mm/slub.c:6291 [inline] kfree+0x1c5/0x6c0 mm/slub.c:6606 sk_prot_free net/core/sock.c:2286 [inline] __sk_destruct+0x74b/0x9d0 net/core/sock.c:2386 l2cap_sock_release+0x1c1/0x270 net/bluetooth/l2cap_sock.c:1463 __sock_release+0xb9/0x250 net/socket.c:726 sock_close+0x1c/0x30 net/socket.c:1529 __fput+0x461/0xa70 fs/file_table.c:510 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x4d0 kernel/entry/common.c:98 The buggy address belongs to the object at ffff88801e6fb000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1920 bytes inside of freed 2048-byte region [ffff88801e6fb000, ffff88801e6fb800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88801e6ff000 pfn:0x1e6f8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000240(workingset|head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000240 ffff88813fe17000 ffffea0001826e10 ffffea0000a7ee10 raw: ffff88801e6ff000 0000000800080006 00000000f5000000 0000000000000000 head: 0080000000000240 ffff88813fe17000 ffffea0001826e10 ffffea0000a7ee10 head: ffff88801e6ff000 0000000800080006 00000000f5000000 0000000000000000 head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1128, tgid 1128 (kworker/u8:8), ts 657502919797, free_ts 657044593503 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1861 prep_new_page mm/page_alloc.c:1869 [inline] get_page_from_freelist+0x27d6/0x2850 mm/page_alloc.c:3949 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5292 alloc_slab_page mm/slub.c:3289 [inline] allocate_slab+0x74/0x5e0 mm/slub.c:3404 new_slab mm/slub.c:3447 [inline] refill_objects+0x33c/0x3d0 mm/slub.c:7319 refill_sheaf mm/slub.c:2827 [inline] __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4664 alloc_from_pcs mm/slub.c:4762 [inline] slab_alloc_node mm/slub.c:4896 [inline] __do_kmalloc_node mm/slub.c:5307 [inline] __kmalloc_node_track_caller_noprof+0x60b/0x7e0 mm/slub.c:5420 kmalloc_reserve net/core/skbuff.c:635 [inline] __alloc_skb+0x2c1/0x7d0 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1381 [inline] mld_newpack+0x14c/0xc90 net/ipv6/mcast.c:1762 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1873 add_grec+0x1452/0x1740 net/ipv6/mcast.c:2012 mld_send_initial_cr+0x288/0x550 net/ipv6/mcast.c:2255 ipv6_mc_dad_complete+0x88/0x540 net/ipv6/mcast.c:2266 addrconf_dad_completed+0x622/0xe60 net/ipv6/addrconf.c:4352 addrconf_dad_work+0xdc4/0x1680 include/linux/rwlock_rt.h:-1 process_one_work+0xa31/0x1980 kernel/workqueue.c:3320 page last free pid 10388 tgid 10388 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1405 [inline] __free_frozen_pages+0x1075/0x11b0 mm/page_alloc.c:2946 __slab_free+0x252/0x2a0 mm/slub.c:5653 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4582 [inline] slab_alloc_node mm/slub.c:4911 [inline] kmem_cache_alloc_noprof+0x33b/0x680 mm/slub.c:4918 vm_area_dup+0x2b/0x670 mm/vma_init.c:123 __split_vma+0x1e4/0xa30 mm/vma.c:516 vms_gather_munmap_vmas+0x32d/0x1380 mm/vma.c:1427 __mmap_setup mm/vma.c:2439 [inline] __mmap_region mm/vma.c:2753 [inline] mmap_region+0x945/0x2280 mm/vma.c:2857 do_mmap+0xc2f/0x10c0 mm/mmap.c:560 vm_mmap_pgoff+0x2cc/0x4f0 mm/util.c:581 ksys_mmap_pgoff+0x4e8/0x720 mm/mmap.c:606 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88801e6fb680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801e6fb700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801e6fb780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801e6fb800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801e6fb880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================