================================================================== BUG: KASAN: use-after-free in __lock_acquire+0xf7/0x7c60 kernel/locking/lockdep.c:4882 Read of size 8 at addr ffff8880199960a0 by task kworker/u5:5/4197 CPU: 0 PID: 4197 Comm: kworker/u5:5 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: hci3 hci_rx_work Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 __lock_acquire+0xf7/0x7c60 kernel/locking/lockdep.c:4882 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x32/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] __lock_sock+0x152/0x2a0 net/core/sock.c:2702 lock_sock_nested+0x9d/0x100 net/core/sock.c:3256 lock_sock include/net/sock.h:1694 [inline] l2cap_sock_recv_cb+0x4c/0x1e0 net/bluetooth/l2cap_sock.c:1499 l2cap_conless_channel net/bluetooth/l2cap_core.c:7775 [inline] l2cap_recv_frame+0xa87/0x7a10 net/bluetooth/l2cap_core.c:7829 hci_acldata_packet net/bluetooth/hci_core.c:4973 [inline] hci_rx_work+0x4a4/0xa10 net/bluetooth/hci_core.c:5165 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 4887: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:609 [inline] sk_prot_alloc+0xe7/0x210 net/core/sock.c:1864 sk_alloc+0x2f/0x310 net/core/sock.c:1917 l2cap_sock_alloc+0x33/0x200 net/bluetooth/l2cap_sock.c:1861 l2cap_sock_create+0x118/0x1d0 net/bluetooth/l2cap_sock.c:1909 bt_sock_create+0x155/0x220 net/bluetooth/af_bluetooth.c:130 __sock_create+0x47b/0x900 net/socket.c:1486 sock_create net/socket.c:1542 [inline] __sys_socket+0xe2/0x170 net/socket.c:1584 __do_sys_socket net/socket.c:1593 [inline] __se_sys_socket net/socket.c:1591 [inline] __x64_sys_socket+0x76/0x80 net/socket.c:1591 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 4887: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xef/0x2a0 mm/slub.c:4559 sk_prot_free net/core/sock.c:1900 [inline] __sk_destruct+0x55a/0x820 net/core/sock.c:1986 l2cap_sock_release+0x154/0x1c0 net/bluetooth/l2cap_sock.c:1429 __sock_release net/socket.c:649 [inline] sock_close+0xd5/0x240 net/socket.c:1336 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 get_signal+0x1222/0x12c0 kernel/signal.c:2672 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x182/0x930 kernel/rcu/tree.c:3091 netlink_release+0x134f/0x1790 net/netlink/af_netlink.c:799 __sock_release net/socket.c:649 [inline] sock_close+0xd5/0x240 net/socket.c:1336 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff888019996000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 160 bytes inside of 2048-byte region [ffff888019996000, ffff888019996800) The buggy address belongs to the page: page:ffffea0000666400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888019994000 pfn:0x19990 head:ffffea0000666400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001e21808 ffffea0001f83608 ffff888016842000 raw: ffff888019994000 0000000000080007 00000001ffffffff 0000000000000000 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 4193, ts 59284098563, free_ts 59138504971 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5474 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1975 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc_trace+0x1a5/0x2a0 mm/slub.c:3245 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:735 [inline] ipv6_add_dev+0xce/0x1190 net/ipv6/addrconf.c:384 addrconf_notify+0x66f/0xf00 net/ipv6/addrconf.c:3577 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] register_netdevice+0x1275/0x16b0 net/core/dev.c:10428 veth_newlink+0x8ed/0xda0 drivers/net/veth.c:1714 __rtnl_newlink net/core/rtnetlink.c:3524 [inline] rtnl_newlink+0x114c/0x17d0 net/core/rtnetlink.c:3572 rtnetlink_rcv_msg+0x9b9/0xe60 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x423/0x580 net/socket.c:2063 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x94/0x280 mm/page_alloc.c:3396 free_slab mm/slub.c:2015 [inline] discard_slab mm/slub.c:2021 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2507 put_cpu_partial+0x12d/0x190 mm/slub.c:2587 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc_trace+0x103/0x2a0 mm/slub.c:3245 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:735 [inline] kobject_uevent_env+0x27a/0x890 lib/kobject_uevent.c:539 __kobject_del+0xd2/0x2f0 lib/kobject.c:625 kobject_cleanup lib/kobject.c:704 [inline] kobject_release lib/kobject.c:744 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x235/0x460 lib/kobject.c:761 net_rx_queue_update_kobjects+0x420/0x490 net/core/net-sysfs.c:1124 netif_set_real_num_rx_queues+0xfe/0x1e0 net/core/dev.c:3019 veth_init_queues+0x10c/0x180 drivers/net/veth.c:1613 veth_newlink+0xab7/0xda0 drivers/net/veth.c:1732 Memory state around the buggy address: ffff888019995f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888019996000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888019996080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888019996100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888019996180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================