================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885 Read of size 8 at addr ffff8880256c6120 by task kworker/0:18/15614 CPU: 0 PID: 15614 Comm: kworker/0:18 Not tainted 5.15.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events l2cap_chan_timeout Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:256 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 lock_sock_nested+0x2f/0xf0 net/core/sock.c:3203 l2cap_sock_teardown_cb+0xa1/0x660 net/bluetooth/l2cap_sock.c:1528 l2cap_chan_del+0xbc/0xa80 net/bluetooth/l2cap_core.c:622 l2cap_chan_close+0x1b9/0xaf0 net/bluetooth/l2cap_core.c:825 l2cap_chan_timeout+0x17e/0x2f0 net/bluetooth/l2cap_core.c:436 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 17904: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 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 mm/kasan/common.c:472 [inline] __kasan_kmalloc+0xa4/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] copy_verifier_state+0x827/0xb80 kernel/bpf/verifier.c:958 is_state_visited kernel/bpf/verifier.c:10776 [inline] do_check kernel/bpf/verifier.c:10895 [inline] do_check_common+0x1b71/0xcf20 kernel/bpf/verifier.c:13154 do_check_main kernel/bpf/verifier.c:13217 [inline] bpf_check+0x8996/0xbd20 kernel/bpf/verifier.c:13784 bpf_prog_load+0xe57/0x21f0 kernel/bpf/syscall.c:2301 __sys_bpf+0x67e/0x5df0 kernel/bpf/syscall.c:4587 __do_sys_bpf kernel/bpf/syscall.c:4691 [inline] __se_sys_bpf kernel/bpf/syscall.c:4689 [inline] __x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:4689 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe9/0x110 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:2987 [inline] call_rcu+0xb1/0x750 kernel/rcu/tree.c:3067 netlink_release+0xdd4/0x1dd0 net/netlink/af_netlink.c:815 __sock_release+0xcd/0x280 net/socket.c:649 sock_close+0x18/0x20 net/socket.c:1314 __fput+0x288/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae Second to last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe9/0x110 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3552 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1647 unregister_sysctl_table fs/proc/proc_sysctl.c:1685 [inline] unregister_sysctl_table+0xc2/0x190 fs/proc/proc_sysctl.c:1660 __devinet_sysctl_unregister net/ipv4/devinet.c:2600 [inline] devinet_sysctl_unregister net/ipv4/devinet.c:2628 [inline] inetdev_destroy net/ipv4/devinet.c:324 [inline] inetdev_event+0xcac/0x15d0 net/ipv4/devinet.c:1598 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1996 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] unregister_netdevice_many+0x951/0x1790 net/core/dev.c:11043 ip_tunnel_delete_nets+0x39f/0x5b0 net/ipv4/ip_tunnel.c:1123 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:591 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff8880256c6000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 288 bytes inside of 2048-byte region [ffff8880256c6000, ffff8880256c6800) The buggy address belongs to the page: page:ffffea000095b000 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880256c6000 pfn:0x256c0 head:ffffea000095b000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0000b90808 ffffea0000658608 ffff888010c42000 raw: ffff8880256c6000 0000000000080007 00000001ffffffff 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 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6574, ts 150179891785, free_ts 146037932250 prep_new_page mm/page_alloc.c:2424 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4153 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5375 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2197 alloc_slab_page mm/slub.c:1763 [inline] allocate_slab mm/slub.c:1900 [inline] new_slab+0x319/0x490 mm/slub.c:1963 ___slab_alloc+0x921/0xfe0 mm/slub.c:2994 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3081 slab_alloc_node mm/slub.c:3172 [inline] __kmalloc_node_track_caller+0x2d2/0x340 mm/slub.c:4936 kmalloc_reserve net/core/skbuff.c:355 [inline] pskb_expand_head+0x15e/0x1060 net/core/skbuff.c:1700 netlink_trim+0x1ea/0x240 net/netlink/af_netlink.c:1301 netlink_broadcast_filtered+0x65/0xdc0 net/netlink/af_netlink.c:1506 netlink_broadcast net/netlink/af_netlink.c:1551 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0x94/0x290 net/netlink/af_netlink.c:2553 rtnl_notify net/core/rtnetlink.c:730 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:3833 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3848 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3836 [inline] rtmsg_ifinfo+0xf0/0x120 net/core/rtnetlink.c:3854 __dev_notify_flags+0x226/0x2b0 net/core/dev.c:8795 dev_change_flags+0x112/0x170 net/core/dev.c:8837 do_setlink+0x96d/0x3970 net/core/rtnetlink.c:2719 __rtnl_newlink+0xde6/0x1750 net/core/rtnetlink.c:3391 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1338 [inline] free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1389 free_unref_page_prepare mm/page_alloc.c:3315 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3394 __unfreeze_partials+0x340/0x360 mm/slub.c:2495 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x95/0xb0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3206 [inline] slab_alloc mm/slub.c:3214 [inline] kmem_cache_alloc+0x209/0x390 mm/slub.c:3219 prepare_kernel_cred+0x27/0x890 kernel/cred.c:724 call_usermodehelper_exec_async+0x10e/0x580 kernel/umh.c:91 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff8880256c6000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880256c6080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880256c6100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880256c6180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880256c6200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================