ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 kobject: kobject_add_internal failed for hci0:201 with -EEXIST, don't try to register things with the same name in the same directory. Bluetooth: hci0: failed to register connection device ================================================================== BUG: KASAN: slab-use-after-free in l2cap_sock_ready_cb+0xd7/0x140 net/bluetooth/l2cap_sock.c:1684 Read of size 8 at addr ffff88805de7c188 by task kworker/u9:7/5852 CPU: 0 UID: 0 PID: 5852 Comm: kworker/u9:7 Not tainted 6.15.0-rc2-syzkaller-00037-g834a4a689699 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: hci0 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 mm/kasan/report.c:634 l2cap_sock_ready_cb+0xd7/0x140 net/bluetooth/l2cap_sock.c:1684 l2cap_chan_ready net/bluetooth/l2cap_core.c:1263 [inline] l2cap_le_start+0x522/0x1800 net/bluetooth/l2cap_core.c:1375 l2cap_conn_ready net/bluetooth/l2cap_core.c:1627 [inline] l2cap_connect_cfm+0x6e2/0x1220 net/bluetooth/l2cap_core.c:7278 hci_connect_cfm+0xa2/0x150 include/net/bluetooth/hci_core.h:2054 le_conn_complete_evt+0xcf4/0x12a0 net/bluetooth/hci_event.c:5779 hci_le_conn_complete_evt+0x18c/0x420 net/bluetooth/hci_event.c:5805 hci_event_func net/bluetooth/hci_event.c:7489 [inline] hci_event_packet+0xa5c/0x1550 net/bluetooth/hci_event.c:7544 hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4020 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 7381: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x9d/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4331 [inline] __kmalloc_noprof+0x28e/0x4d0 mm/slub.c:4343 kmalloc_noprof include/linux/slab.h:909 [inline] sk_prot_alloc+0xe0/0x210 net/core/sock.c:2198 sk_alloc+0x3e/0x370 net/core/sock.c:2254 bt_sock_alloc+0x3c/0x340 net/bluetooth/af_bluetooth.c:148 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1891 [inline] l2cap_sock_create+0x13d/0x300 net/bluetooth/l2cap_sock.c:1933 bt_sock_create+0x161/0x230 net/bluetooth/af_bluetooth.c:132 __sock_create+0x4c0/0xa30 net/socket.c:1541 sock_create net/socket.c:1599 [inline] __sys_socket_create net/socket.c:1636 [inline] __sys_socket+0x14d/0x3c0 net/socket.c:1683 __do_sys_socket net/socket.c:1697 [inline] __se_sys_socket net/socket.c:1695 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1695 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 7381: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2389 [inline] slab_free mm/slub.c:4646 [inline] kfree+0x198/0x430 mm/slub.c:4845 sk_prot_free net/core/sock.c:2237 [inline] __sk_destruct+0x4ce/0x650 net/core/sock.c:2332 l2cap_sock_release+0x15b/0x1d0 net/bluetooth/l2cap_sock.c:1435 __sock_release net/socket.c:647 [inline] sock_close+0xbc/0x240 net/socket.c:1391 __fput+0x3e9/0x9f0 fs/file_table.c:465 task_work_run+0x251/0x310 kernel/task_work.c:227 get_signal+0x15db/0x1730 kernel/signal.c:2807 arch_do_signal_or_restart+0x98/0x840 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805de7c000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 392 bytes inside of freed 2048-byte region [ffff88805de7c000, ffff88805de7c800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5de78 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 ffff88801b042000 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b042000 0000000000000000 dead000000000001 head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001779e01 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 6403, tgid 6403 (syz-executor), ts 139475558397, free_ts 139448295612 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1717 prep_new_page mm/page_alloc.c:1725 [inline] get_page_from_freelist+0x351d/0x36b0 mm/page_alloc.c:3652 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4934 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2459 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2623 new_slab mm/slub.c:2676 [inline] ___slab_alloc+0xc3b/0x1500 mm/slub.c:3862 __slab_alloc+0x58/0xa0 mm/slub.c:3952 __slab_alloc_node mm/slub.c:4027 [inline] slab_alloc_node mm/slub.c:4188 [inline] __do_kmalloc_node mm/slub.c:4330 [inline] __kmalloc_node_track_caller_noprof+0x2ef/0x4d0 mm/slub.c:4350 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:599 pskb_expand_head+0x1fd/0x1510 net/core/skbuff.c:2247 netlink_trim+0x1d6/0x2e0 net/netlink/af_netlink.c:1295 netlink_broadcast_filtered+0x76/0x12a0 net/netlink/af_netlink.c:1501 nlmsg_multicast_filtered include/net/netlink.h:1129 [inline] nlmsg_multicast include/net/netlink.h:1148 [inline] nlmsg_notify+0xfb/0x1c0 net/netlink/af_netlink.c:2577 __dev_notify_flags+0xf9/0x410 net/core/dev.c:9399 rtnl_configure_link+0x22d/0x340 net/core/rtnetlink.c:-1 veth_newlink+0x53f/0xb80 drivers/net/veth.c:1828 page last free pid 6495 tgid 6488 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xddf/0x10a0 mm/page_alloc.c:2680 discard_slab mm/slub.c:2720 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3189 put_cpu_partial+0x17e/0x250 mm/slub.c:3264 __slab_free+0x294/0x390 mm/slub.c:4516 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4151 [inline] slab_alloc_node mm/slub.c:4200 [inline] kmem_cache_alloc_node_noprof+0x1f2/0x3b0 mm/slub.c:4252 __alloc_skb+0x1c2/0x480 net/core/skbuff.c:658 alloc_skb include/linux/skbuff.h:1340 [inline] __ip6_append_data+0x2d15/0x41b0 net/ipv6/ip6_output.c:1667 ip6_append_data+0x25f/0x380 net/ipv6/ip6_output.c:1857 rawv6_sendmsg+0x1855/0x23c0 net/ipv6/raw.c:911 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:727 ____sys_sendmsg+0x523/0x860 net/socket.c:2566 ___sys_sendmsg net/socket.c:2620 [inline] __sys_sendmmsg+0x3a0/0x7b0 net/socket.c:2709 __do_sys_sendmmsg net/socket.c:2736 [inline] __se_sys_sendmmsg net/socket.c:2733 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2733 Memory state around the buggy address: ffff88805de7c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805de7c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805de7c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805de7c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805de7c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================