================================================================== BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] BUG: KASAN: use-after-free in __mutex_lock_common+0xae8/0x1f38 kernel/locking/mutex.c:681 Read of size 8 at addr ffff0000ee370060 by task khidpd_0c45000b/4478 CPU: 0 PID: 4478 Comm: khidpd_0c45000b Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 print_address_description+0x88/0x218 mm/kasan/report.c:316 print_report+0x50/0x68 mm/kasan/report.c:420 kasan_report+0xa8/0x100 mm/kasan/report.c:524 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:351 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] __mutex_lock_common+0xae8/0x1f38 kernel/locking/mutex.c:681 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 l2cap_unregister_user+0x70/0x18c net/bluetooth/l2cap_core.c:1895 hidp_session_thread+0x3d0/0x46c net/bluetooth/hidp/core.c:1305 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850 Allocated by task 4473: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_alloc_info+0x28/0x34 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node_track_caller+0xe0/0x16c mm/slab_common.c:956 kmalloc_reserve net/core/skbuff.c:446 [inline] __alloc_skb+0x264/0x718 net/core/skbuff.c:515 alloc_skb include/linux/skbuff.h:1271 [inline] nlmsg_new include/net/netlink.h:991 [inline] fdb_notify+0xa4/0x164 net/bridge/br_fdb.c:191 br_fdb_update+0x33c/0x490 net/bridge/br_fdb.c:888 br_handle_frame_finish+0x4c0/0x1308 net/bridge/br_input.c:124 br_nf_hook_thresh+0x304/0x3c8 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x878/0xb9c net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:302 [inline] br_nf_pre_routing_ipv6+0x29c/0x588 net/bridge/br_netfilter_ipv6.c:243 br_nf_pre_routing+0x5bc/0x11d8 net/bridge/br_netfilter_hooks.c:530 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_bridge_pre net/bridge/br_input.c:260 [inline] br_handle_frame+0x78c/0xffc net/bridge/br_input.c:406 __netif_receive_skb_core+0xcd8/0x3120 net/core/dev.c:5475 __netif_receive_skb_one_core net/core/dev.c:5579 [inline] __netif_receive_skb+0x78/0x2ac net/core/dev.c:5695 process_backlog+0x408/0x714 net/core/dev.c:6023 __napi_poll+0xb4/0x3f0 net/core/dev.c:6590 napi_poll net/core/dev.c:6657 [inline] net_rx_action+0x50c/0xb10 net/core/dev.c:6771 handle_softirqs+0x318/0xc6c kernel/softirq.c:596 __do_softirq+0x14/0x20 kernel/softirq.c:630 Freed by task 4473: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_free_info+0x3c/0x60 mm/kasan/generic.c:516 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:236 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x16c/0x1ec mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xc0/0x224 mm/slub.c:3700 kfree+0xd0/0x1ac mm/slab_common.c:988 skb_free_head net/core/skbuff.c:762 [inline] skb_release_data+0x43c/0x648 net/core/skbuff.c:791 skb_release_all net/core/skbuff.c:856 [inline] __kfree_skb net/core/skbuff.c:870 [inline] consume_skb+0xa0/0x104 net/core/skbuff.c:1035 netlink_broadcast+0xf30/0x108c net/netlink/af_netlink.c:1521 nlmsg_multicast include/net/netlink.h:1071 [inline] nlmsg_notify+0xf4/0x1d8 net/netlink/af_netlink.c:2554 rtnl_notify+0xa0/0xd8 net/core/rtnetlink.c:796 fdb_notify+0xfc/0x164 net/bridge/br_fdb.c:202 br_fdb_update+0x33c/0x490 net/bridge/br_fdb.c:888 br_handle_frame_finish+0x4c0/0x1308 net/bridge/br_input.c:124 br_nf_hook_thresh+0x304/0x3c8 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x878/0xb9c net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:302 [inline] br_nf_pre_routing_ipv6+0x29c/0x588 net/bridge/br_netfilter_ipv6.c:243 br_nf_pre_routing+0x5bc/0x11d8 net/bridge/br_netfilter_hooks.c:530 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_bridge_pre net/bridge/br_input.c:260 [inline] br_handle_frame+0x78c/0xffc net/bridge/br_input.c:406 __netif_receive_skb_core+0xcd8/0x3120 net/core/dev.c:5475 __netif_receive_skb_one_core net/core/dev.c:5579 [inline] __netif_receive_skb+0x78/0x2ac net/core/dev.c:5695 process_backlog+0x408/0x714 net/core/dev.c:6023 __napi_poll+0xb4/0x3f0 net/core/dev.c:6590 napi_poll net/core/dev.c:6657 [inline] net_rx_action+0x50c/0xb10 net/core/dev.c:6771 handle_softirqs+0x318/0xc6c kernel/softirq.c:596 __do_softirq+0x14/0x20 kernel/softirq.c:630 The buggy address belongs to the object at ffff0000ee370000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 96 bytes inside of 512-byte region [ffff0000ee370000, ffff0000ee370200) The buggy address belongs to the physical page: page:0000000063722e20 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12e370 head:0000000063722e20 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 0000000000000000 dead000000000122 ffff0000c0002600 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000ee36ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000ee36ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff0000ee370000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000ee370080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000ee370100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================