================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885 Read of size 8 at addr ffff888073c970a0 by task kworker/0:3/6935 CPU: 0 PID: 6935 Comm: kworker/0:3 Not tainted 5.15.0-rc1-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/0x2d6 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 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] lock_sock_nested+0x40/0x120 net/core/sock.c:3183 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 6961: 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+0xa1/0xd0 mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:264 [inline] __do_kmalloc mm/slab.c:3702 [inline] __kmalloc+0x214/0x4d0 mm/slab.c:3711 kmalloc include/linux/slab.h:596 [inline] sk_prot_alloc+0x110/0x290 net/core/sock.c:1822 sk_alloc+0x30/0xa60 net/core/sock.c:1875 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:1464 sock_create net/socket.c:1515 [inline] __sys_socket+0xef/0x200 net/socket.c:1557 __do_sys_socket net/socket.c:1566 [inline] __se_sys_socket net/socket.c:1564 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1564 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 6961: 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+0xd1/0x110 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] __cache_free mm/slab.c:3445 [inline] kfree+0x10a/0x2c0 mm/slab.c:3803 sk_prot_free net/core/sock.c:1858 [inline] __sk_destruct+0x6a8/0x900 net/core/sock.c:1943 sk_destruct+0xbd/0xe0 net/core/sock.c:1958 __sk_free+0xef/0x3d0 net/core/sock.c:1969 sk_free+0x78/0xa0 net/core/sock.c:1980 sock_put include/net/sock.h:1815 [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: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 get_signal+0x1b35/0x2160 kernel/signal.c:2641 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 The buggy address belongs to the object at ffff888073c97000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 160 bytes inside of 2048-byte region [ffff888073c97000, ffff888073c97800) The buggy address belongs to the page: page:ffffea0001cf25c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x73c97 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0001e89a08 ffffea000084e008 ffff888010c40800 raw: 0000000000000000 ffff888073c97000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x242220(__GFP_HIGH|__GFP_ATOMIC|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 6961, ts 1583451995388, free_ts 78015950690 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_node include/linux/gfp.h:570 [inline] kmem_getpages mm/slab.c:1377 [inline] cache_grow_begin+0x75/0x460 mm/slab.c:2593 cache_alloc_refill+0x27f/0x380 mm/slab.c:2965 ____cache_alloc mm/slab.c:3048 [inline] ____cache_alloc mm/slab.c:3031 [inline] __do_cache_alloc mm/slab.c:3275 [inline] slab_alloc mm/slab.c:3316 [inline] __do_kmalloc mm/slab.c:3700 [inline] __kmalloc+0x3d5/0x4d0 mm/slab.c:3711 kmalloc include/linux/slab.h:596 [inline] sk_prot_alloc+0x110/0x290 net/core/sock.c:1822 sk_alloc+0x30/0xa60 net/core/sock.c:1875 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:1464 sock_create net/socket.c:1515 [inline] __sys_socket+0xef/0x200 net/socket.c:1557 __do_sys_socket net/socket.c:1566 [inline] __se_sys_socket net/socket.c:1564 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1564 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 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 slab_destroy mm/slab.c:1627 [inline] slabs_destroy+0x89/0xc0 mm/slab.c:1647 cache_flusharray mm/slab.c:3418 [inline] ___cache_free+0x4c6/0x610 mm/slab.c:3480 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x4e/0x110 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x92/0xa0 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 mm/slab.c:3323 [inline] kmem_cache_alloc+0x25f/0x540 mm/slab.c:3507 vm_area_dup+0x88/0x2b0 kernel/fork.c:357 dup_mmap kernel/fork.c:552 [inline] dup_mm+0x5fa/0x13e0 kernel/fork.c:1453 copy_mm kernel/fork.c:1505 [inline] copy_process+0x6fcf/0x7580 kernel/fork.c:2194 kernel_clone+0xe7/0xac0 kernel/fork.c:2584 __do_sys_clone+0xc8/0x110 kernel/fork.c:2701 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 Memory state around the buggy address: ffff888073c96f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888073c97000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888073c97080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888073c97100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888073c97180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================