================================================================== BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0x70a/0x1220 net/bluetooth/l2cap_core.c:7278 Read of size 8 at addr ffff888034970480 by task kworker/u9:2/5832 CPU: 1 UID: 0 PID: 5832 Comm: kworker/u9:2 Not tainted 6.13.0-rc1-next-20241205-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci1 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:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 l2cap_connect_cfm+0x70a/0x1220 net/bluetooth/l2cap_core.c:7278 hci_connect_cfm+0xa2/0x150 include/net/bluetooth/hci_core.h:2035 le_conn_complete_evt+0xd3e/0x12e0 net/bluetooth/hci_event.c:5763 hci_le_conn_complete_evt+0x18c/0x420 net/bluetooth/hci_event.c:5789 hci_event_func net/bluetooth/hci_event.c:7481 [inline] hci_event_packet+0xa55/0x1540 net/bluetooth/hci_event.c:7536 hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4039 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 5832: 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+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4314 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] l2cap_chan_create+0x50/0x760 net/bluetooth/l2cap_core.c:449 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1888 [inline] l2cap_sock_new_connection_cb+0x181/0x2d0 net/bluetooth/l2cap_sock.c:1470 l2cap_connect_cfm+0x377/0x1220 net/bluetooth/l2cap_core.c:7261 hci_connect_cfm+0xa2/0x150 include/net/bluetooth/hci_core.h:2035 le_conn_complete_evt+0xd3e/0x12e0 net/bluetooth/hci_event.c:5763 hci_le_conn_complete_evt+0x18c/0x420 net/bluetooth/hci_event.c:5789 hci_event_func net/bluetooth/hci_event.c:7481 [inline] hci_event_packet+0xa55/0x1540 net/bluetooth/hci_event.c:7536 hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4039 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 17597: 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:2338 [inline] slab_free mm/slub.c:4598 [inline] kfree+0x196/0x430 mm/slub.c:4746 l2cap_sock_cleanup_listen+0xed/0x3c0 net/bluetooth/l2cap_sock.c:1453 l2cap_sock_teardown_cb+0x1b2/0x440 net/bluetooth/l2cap_sock.c:1589 l2cap_chan_close+0x2cb/0x9f0 l2cap_sock_shutdown+0xa64/0x1020 net/bluetooth/l2cap_sock.c:1372 l2cap_sock_release+0x79/0x1d0 net/bluetooth/l2cap_sock.c:1416 __sock_release net/socket.c:640 [inline] sock_close+0xbc/0x240 net/socket.c:1408 __fput+0x23c/0xa50 fs/file_table.c:450 task_work_run+0x24f/0x310 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888034970000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1152 bytes inside of freed 2048-byte region [ffff888034970000, ffff888034970800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x34970 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac42000 ffffea000086b400 dead000000000002 raw: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac42000 ffffea000086b400 dead000000000002 head: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000d25c01 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 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 0xd28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5837, tgid 5837 (syz-executor), ts 60114196142, free_ts 60109710873 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1549 prep_new_page mm/page_alloc.c:1557 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3475 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4752 alloc_pages_mpol+0x30e/0x550 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2408 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2574 new_slab mm/slub.c:2627 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3815 __slab_alloc+0x58/0xa0 mm/slub.c:3905 __slab_alloc_node mm/slub.c:3980 [inline] slab_alloc_node mm/slub.c:4141 [inline] __do_kmalloc_node mm/slub.c:4282 [inline] __kmalloc_node_track_caller_noprof+0x2e9/0x4c0 mm/slub.c:4302 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609 pskb_expand_head+0x1f0/0x1380 net/core/skbuff.c:2275 netlink_trim+0x183/0x220 net/netlink/af_netlink.c:1303 netlink_broadcast_filtered+0x76/0x12a0 net/netlink/af_netlink.c:1509 nlmsg_multicast_filtered include/net/netlink.h:1128 [inline] nlmsg_multicast include/net/netlink.h:1147 [inline] nlmsg_notify+0xfb/0x1c0 net/netlink/af_netlink.c:2585 register_netdevice+0x1774/0x1b00 net/core/dev.c:10646 __ip_tunnel_create+0x2b4/0x380 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x21c/0x720 net/ipv4/ip_tunnel.c:1160 page last free pid 5828 tgid 5828 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2658 __slab_free+0x2c2/0x380 mm/slub.c:4509 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:4104 [inline] slab_alloc_node mm/slub.c:4153 [inline] __kmalloc_cache_noprof+0x1d9/0x390 mm/slub.c:4309 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] dropmon_net_event+0x220/0x2a0 net/core/drop_monitor.c:1586 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2034 [inline] call_netdevice_notifiers net/core/dev.c:2048 [inline] register_netdevice+0x167f/0x1b00 net/core/dev.c:10632 register_netdev+0x3b/0x50 net/core/dev.c:10736 sit_init_net+0x1f9/0x500 net/ipv6/sit.c:1861 ops_init+0x31e/0x590 net/core/net_namespace.c:138 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:500 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 Memory state around the buggy address: ffff888034970380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888034970400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888034970480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888034970500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888034970580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================