Bluetooth: hci5: failed to register connection device ================================================================== BUG: KASAN: slab-use-after-free in l2cap_sock_new_connection_cb+0x1f9/0x2b0 net/bluetooth/l2cap_sock.c:1500 Read of size 8 at addr ffff888043611598 by task kworker/u9:5/5842 CPU: 0 UID: 0 PID: 5842 Comm: kworker/u9:5 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: hci5 hci_rx_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 l2cap_sock_new_connection_cb+0x1f9/0x2b0 net/bluetooth/l2cap_sock.c:1500 l2cap_connect_cfm+0x37a/0x1040 net/bluetooth/l2cap_core.c:7287 hci_connect_cfm+0x95/0x140 include/net/bluetooth/hci_core.h:2106 le_conn_complete_evt+0xfb8/0x1500 net/bluetooth/hci_event.c:5789 hci_le_conn_complete_evt+0x187/0x450 net/bluetooth/hci_event.c:5815 hci_event_func net/bluetooth/hci_event.c:7560 [inline] hci_event_packet+0x78f/0x1200 net/bluetooth/hci_event.c:7617 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4099 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5842: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5604 [inline] __kmalloc_noprof+0x411/0x7f0 mm/slub.c:5616 kmalloc_noprof include/linux/slab.h:961 [inline] sk_prot_alloc+0xe7/0x220 net/core/sock.c:2239 sk_alloc+0x3a/0x370 net/core/sock.c:2295 bt_sock_alloc+0x3b/0x310 net/bluetooth/af_bluetooth.c:151 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1897 [inline] l2cap_sock_new_connection_cb+0xe2/0x2b0 net/bluetooth/l2cap_sock.c:1485 l2cap_connect_cfm+0x37a/0x1040 net/bluetooth/l2cap_core.c:7287 hci_connect_cfm+0x95/0x140 include/net/bluetooth/hci_core.h:2106 le_conn_complete_evt+0xfb8/0x1500 net/bluetooth/hci_event.c:5789 hci_le_conn_complete_evt+0x187/0x450 net/bluetooth/hci_event.c:5815 hci_event_func net/bluetooth/hci_event.c:7560 [inline] hci_event_packet+0x78f/0x1200 net/bluetooth/hci_event.c:7617 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4099 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 11322: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2515 [inline] slab_free mm/slub.c:6574 [inline] kfree+0x19a/0x6d0 mm/slub.c:6781 sk_prot_free net/core/sock.c:2278 [inline] __sk_destruct+0x4e1/0x660 net/core/sock.c:2373 l2cap_sock_cleanup_listen+0xda/0x3e0 net/bluetooth/l2cap_sock.c:1465 l2cap_sock_release+0x6a/0x210 net/bluetooth/l2cap_sock.c:1426 __sock_release net/socket.c:662 [inline] sock_close+0xc3/0x240 net/socket.c:1455 __fput+0x44c/0xa70 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 get_signal+0x11ec/0x1340 kernel/signal.c:2807 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888043611000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1432 bytes inside of freed 2048-byte region [ffff888043611000, ffff888043611800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x43610 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813fe27000 0000000000000000 0000000000000001 raw: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813fe27000 0000000000000000 0000000000000001 head: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea00010d8401 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 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 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 10975, tgid 10975 (syz-executor), ts 504112986064, free_ts 504102447217 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3031 [inline] allocate_slab+0x96/0x3a0 mm/slub.c:3204 new_slab mm/slub.c:3258 [inline] ___slab_alloc+0xe94/0x18a0 mm/slub.c:4628 __slab_alloc+0x65/0x100 mm/slub.c:4747 __slab_alloc_node mm/slub.c:4823 [inline] slab_alloc_node mm/slub.c:5234 [inline] __do_kmalloc_node mm/slub.c:5603 [inline] __kmalloc_node_track_caller_noprof+0x5c7/0x800 mm/slub.c:5713 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601 pskb_expand_head+0x18e/0x1150 net/core/skbuff.c:2241 netlink_trim+0x1d5/0x2e0 net/netlink/af_netlink.c:1301 netlink_broadcast_filtered+0xd6/0x1000 net/netlink/af_netlink.c:1514 nlmsg_multicast_filtered include/net/netlink.h:1165 [inline] nlmsg_multicast include/net/netlink.h:1184 [inline] nlmsg_notify+0xf0/0x1a0 net/netlink/af_netlink.c:2595 __dev_notify_flags+0xf4/0x2e0 net/core/dev.c:9672 rtnl_configure_link+0x22c/0x350 net/core/rtnetlink.c:3599 veth_newlink+0x4ad/0xa60 drivers/net/veth.c:1865 page last free pid 10975 tgid 10975 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906 discard_slab mm/slub.c:3302 [inline] __put_partials+0x146/0x170 mm/slub.c:3849 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3924 __slab_free+0x2b9/0x390 mm/slub.c:5883 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4947 [inline] slab_alloc_node mm/slub.c:5246 [inline] __kmalloc_cache_noprof+0x36f/0x6f0 mm/slub.c:5720 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] kobject_uevent_env+0x27c/0x8c0 lib/kobject_uevent.c:540 __kobject_del+0xd2/0x300 lib/kobject.c:601 kobject_cleanup lib/kobject.c:680 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x243/0x480 lib/kobject.c:737 net_rx_queue_update_kobjects+0x6a6/0x750 net/core/net-sysfs.c:1338 netif_set_real_num_rx_queues+0x217/0x360 net/core/dev.c:3232 veth_init_queues drivers/net/veth.c:1798 [inline] veth_newlink+0x861/0xa60 drivers/net/veth.c:1902 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3833 __rtnl_newlink net/core/rtnetlink.c:3950 [inline] rtnl_newlink+0x16e4/0x1c80 net/core/rtnetlink.c:4065 Memory state around the buggy address: ffff888043611480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888043611500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888043611580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888043611600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888043611680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================