================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885 Read of size 8 at addr ffff888029d5b0a0 by task kworker/1:0/8445 CPU: 1 PID: 8445 Comm: kworker/1:0 Not tainted 5.14.0-rc6-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:105 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:436 __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 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:359 [inline] lock_sock_nested+0x40/0x120 net/core/sock.c:3162 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+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 12535: 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+0x9b/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:596 [inline] sk_prot_alloc+0x110/0x290 net/core/sock.c:1808 sk_alloc+0x32/0xbc0 net/core/sock.c:1861 l2cap_sock_alloc.constprop.0+0x31/0x230 net/bluetooth/l2cap_sock.c:1813 l2cap_sock_create+0x123/0x1f0 net/bluetooth/l2cap_sock.c:1859 bt_sock_create+0x17c/0x340 net/bluetooth/af_bluetooth.c:130 __sock_create+0x353/0x790 net/socket.c:1450 sock_create net/socket.c:1501 [inline] __sys_socket+0xef/0x200 net/socket.c:1543 __do_sys_socket net/socket.c:1552 [inline] __se_sys_socket net/socket.c:1550 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1550 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 Freed by task 12536: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1628 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1653 slab_free mm/slub.c:3213 [inline] kfree+0xe4/0x540 mm/slub.c:4267 sk_prot_free net/core/sock.c:1844 [inline] __sk_destruct+0x6a8/0x900 net/core/sock.c:1929 sk_destruct+0xbd/0xe0 net/core/sock.c:1944 __sk_free+0xef/0x3d0 net/core/sock.c:1955 sk_free+0x78/0xa0 net/core/sock.c:1966 sock_put include/net/sock.h:1816 [inline] l2cap_sock_kill+0x203/0x240 net/bluetooth/l2cap_sock.c:1227 l2cap_sock_release+0x184/0x200 net/bluetooth/l2cap_sock.c:1397 __sock_release+0xcd/0x280 net/socket.c:648 sock_close+0x18/0x20 net/socket.c:1300 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 get_signal+0x1b35/0x2160 kernel/signal.c:2581 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 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+0xe5/0x110 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3029 [inline] call_rcu+0xb1/0x750 kernel/rcu/tree.c:3109 netlink_release+0xdd4/0x1dd0 net/netlink/af_netlink.c:812 __sock_release+0xcd/0x280 net/socket.c:648 sock_close+0x18/0x20 net/socket.c:1300 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xbd4/0x2a60 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 __do_sys_exit_group kernel/exit.c:933 [inline] __se_sys_exit_group kernel/exit.c:931 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:931 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 Second to last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3029 [inline] call_rcu+0xb1/0x750 kernel/rcu/tree.c:3109 netlink_release+0xdd4/0x1dd0 net/netlink/af_netlink.c:812 __sock_release+0xcd/0x280 net/socket.c:648 sock_close+0x18/0x20 net/socket.c:1300 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xbd4/0x2a60 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 __do_sys_exit_group kernel/exit.c:933 [inline] __se_sys_exit_group kernel/exit.c:931 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:931 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 The buggy address belongs to the object at ffff888029d5b000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 160 bytes inside of 2048-byte region [ffff888029d5b000, ffff888029d5b800) The buggy address belongs to the page: page:ffffea0000a75600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29d58 head:ffffea0000a75600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010842000 raw: 0000000000000000 0000000080080008 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 1, ts 11277830666, free_ts 0 prep_new_page mm/page_alloc.c:2436 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4169 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5391 alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2244 alloc_slab_page mm/slub.c:1691 [inline] allocate_slab+0x32e/0x4b0 mm/slub.c:1831 new_slab mm/slub.c:1894 [inline] new_slab_objects mm/slub.c:2640 [inline] ___slab_alloc+0x4ba/0x820 mm/slub.c:2803 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2843 slab_alloc_node mm/slub.c:2925 [inline] __kmalloc_node_track_caller+0x2e3/0x360 mm/slub.c:4653 kmalloc_reserve net/core/skbuff.c:355 [inline] pskb_expand_head+0x15e/0x1060 net/core/skbuff.c:1696 netlink_trim+0x1ea/0x240 net/netlink/af_netlink.c:1296 netlink_broadcast_filtered+0x65/0xdc0 net/netlink/af_netlink.c:1501 netlink_broadcast net/netlink/af_netlink.c:1546 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0x90/0x250 net/netlink/af_netlink.c:2547 rtnl_notify net/core/rtnetlink.c:741 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:3835 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3850 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3838 [inline] rtmsg_ifinfo+0xf0/0x120 net/core/rtnetlink.c:3856 __dev_notify_flags+0x226/0x2b0 net/core/dev.c:8856 dev_change_flags+0x112/0x170 net/core/dev.c:8898 do_setlink+0x90a/0x3900 net/core/rtnetlink.c:2721 rtnl_setlink+0x24d/0x3c0 net/core/rtnetlink.c:3014 page_owner free stack trace missing Memory state around the buggy address: ffff888029d5af80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888029d5b000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888029d5b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888029d5b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888029d5b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================