================================================================== BUG: KASAN: use-after-free in __lock_acquire+0xf0/0x651c kernel/locking/lockdep.c:4882 Read of size 8 at addr ffff0000eca40888 by task syz.3.16163/5771 CPU: 0 PID: 5771 Comm: syz.3.16163 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 Call trace: dump_backtrace+0x0/0x43c arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 print_address_description+0x78/0x30c mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xec/0x15c mm/kasan/report.c:451 __asan_report_load8_noabort+0x44/0x50 mm/kasan/report_generic.c:309 __lock_acquire+0xf0/0x651c kernel/locking/lockdep.c:4882 lock_acquire+0x1f4/0x620 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xc4/0x14c kernel/locking/spinlock.c:162 skb_dequeue net/core/skbuff.c:3285 [inline] skb_queue_purge+0x3c/0x1a0 net/core/skbuff.c:3323 vhci_flush+0x48/0x5c drivers/bluetooth/hci_vhci.c:60 hci_dev_do_reset net/bluetooth/hci_core.c:1907 [inline] hci_dev_reset+0x324/0x508 net/bluetooth/hci_core.c:1942 hci_sock_ioctl+0x5f0/0x94c net/bluetooth/hci_sock.c:1072 sock_do_ioctl+0xf8/0x240 net/socket.c:1140 sock_ioctl+0x5c8/0x87c net/socket.c:1257 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Allocated by task 5754: 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+0xb0/0xf0 mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:264 [inline] kmem_cache_alloc_trace+0x274/0x3fc mm/slub.c:3252 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:735 [inline] vhci_open+0x60/0x268 drivers/bluetooth/hci_vhci.c:317 misc_open+0x2f0/0x368 drivers/char/misc.c:141 chrdev_open+0x26c/0x4f0 fs/char_dev.c:414 do_dentry_open+0x760/0xebc fs/open.c:826 vfs_open+0x7c/0x90 fs/open.c:956 do_open fs/namei.c:3608 [inline] path_openat+0x1f80/0x26e4 fs/namei.c:3742 do_filp_open+0x164/0x330 fs/namei.c:3769 do_sys_openat2+0x128/0x3d8 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __arm64_sys_openat+0x120/0x154 fs/open.c:1280 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Freed by task 5765: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x84 mm/kasan/common.c:46 kasan_set_free_info+0x28/0x4c mm/kasan/generic.c:360 ____kasan_slab_free+0x118/0x164 mm/kasan/common.c:366 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0x128/0x1e8 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kfree+0x170/0x40c mm/slub.c:4564 vhci_release+0xa8/0xc4 drivers/bluetooth/hci_vhci.c:351 __fput+0x1c0/0x7f8 fs/file_table.c:311 ____fput+0x20/0x30 fs/file_table.c:339 task_work_run+0x12c/0x1e0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x684/0x1f58 kernel/exit.c:883 do_group_exit+0x100/0x268 kernel/exit.c:997 get_signal+0x73c/0x1340 kernel/signal.c:2900 do_signal arch/arm64/kernel/signal.c:893 [inline] do_notify_resume+0x35c/0x3128 arch/arm64/kernel/signal.c:946 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xf0/0x1e0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xcc/0x114 mm/kasan/generic.c:348 kvfree_call_rcu+0xb8/0x66c kernel/rcu/tree.c:3600 ma_put+0x11c/0x1c0 net/ipv6/mcast.c:869 __ipv6_dev_mc_dec+0x2b0/0x320 net/ipv6/mcast.c:981 addrconf_leave_solict net/ipv6/addrconf.c:2213 [inline] __ipv6_ifa_notify+0x5e8/0xbf4 net/ipv6/addrconf.c:6201 addrconf_ifdown+0xc6c/0x1688 net/ipv6/addrconf.c:3899 addrconf_notify+0x2f4/0xc6c net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] unregister_netdevice_many+0xe10/0x17d0 net/core/dev.c:11134 default_device_exit_batch+0x444/0x4a4 net/core/dev.c:11667 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x644/0xa98 net/core/net_namespace.c:635 process_one_work+0x79c/0x1140 kernel/workqueue.c:2310 worker_thread+0x8f4/0x101c kernel/workqueue.c:2457 kthread+0x374/0x454 kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:856 Second to last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xcc/0x114 mm/kasan/generic.c:348 kvfree_call_rcu+0xb8/0x66c kernel/rcu/tree.c:3600 drop_sysctl_table+0x274/0x39c fs/proc/proc_sysctl.c:1685 drop_sysctl_table+0x294/0x39c fs/proc/proc_sysctl.c:1688 unregister_sysctl_table+0x94/0x134 fs/proc/proc_sysctl.c:1723 unregister_net_sysctl_table+0x20/0x30 net/sysctl_net.c:175 neigh_sysctl_unregister+0x78/0x9c net/core/neighbour.c:3737 addrconf_sysctl_unregister net/ipv6/addrconf.c:7160 [inline] addrconf_ifdown+0x1368/0x1688 net/ipv6/addrconf.c:3928 addrconf_notify+0x2f4/0xc6c net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] unregister_netdevice_many+0xe10/0x17d0 net/core/dev.c:11134 default_device_exit_batch+0x444/0x4a4 net/core/dev.c:11667 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x644/0xa98 net/core/net_namespace.c:635 process_one_work+0x79c/0x1140 kernel/workqueue.c:2310 worker_thread+0x8f4/0x101c kernel/workqueue.c:2457 kthread+0x374/0x454 kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:856 The buggy address belongs to the object at ffff0000eca40800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 136 bytes inside of 512-byte region [ffff0000eca40800, ffff0000eca40a00) The buggy address belongs to the page: page:00000000a6149657 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12ca40 head:00000000a6149657 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 fffffc00030ab300 0000000700000002 ffff0000c0002600 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000eca40780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000eca40800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000eca40880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000eca40900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000eca40980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================