================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885 Read of size 8 at addr ffff888079217120 by task kworker/2:2/2800 CPU: 2 PID: 2800 Comm: kworker/2:2 Not tainted 5.15.0-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 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 11354: 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:596 [inline] sk_prot_alloc+0x110/0x290 net/core/sock.c:1839 sk_alloc+0x30/0xa60 net/core/sock.c:1892 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] __ia32_sys_socket+0x6f/0xb0 net/socket.c:1564 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Freed by task 11358: 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+0xff/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1700 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1726 slab_free mm/slub.c:3492 [inline] kfree+0xf3/0x550 mm/slub.c:4552 sk_prot_free net/core/sock.c:1875 [inline] __sk_destruct+0x6a8/0x900 net/core/sock.c:1961 sk_destruct+0xbd/0xe0 net/core/sock.c:1976 __sk_free+0xef/0x3d0 net/core/sock.c:1987 sk_free+0x78/0xa0 net/core/sock.c:1998 sock_put include/net/sock.h:1848 [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+0x1b84/0x21d0 kernel/signal.c:2628 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: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_fast_syscall_32+0x72/0xf0 arch/x86/entry/common.c:181 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c The buggy address belongs to the object at ffff888079217000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 288 bytes inside of 2048-byte region [ffff888079217000, ffff888079217800) The buggy address belongs to the page: page:ffffea0001e48400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x79210 head:ffffea0001e48400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4fff00000010200(slab|head|node=1|zone=1|lastcpupid=0x7ff) raw: 04fff00000010200 0000000000000000 0000000100000001 ffff888010c42f00 raw: 0000000000000000 0000000000080008 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 0x152a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 10231, ts 504819247913, free_ts 504818363127 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4155 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5381 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191 alloc_slab_page mm/slub.c:1770 [inline] allocate_slab mm/slub.c:1907 [inline] new_slab+0x319/0x490 mm/slub.c:1970 ___slab_alloc+0x950/0x1050 mm/slub.c:3001 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3088 slab_alloc_node mm/slub.c:3179 [inline] slab_alloc mm/slub.c:3221 [inline] __kmalloc+0x305/0x320 mm/slub.c:4396 kmalloc include/linux/slab.h:596 [inline] sk_prot_alloc+0x110/0x290 net/core/sock.c:1839 sk_alloc+0x30/0xa60 net/core/sock.c:1892 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] __ia32_sys_socket+0x6f/0xb0 net/socket.c:1564 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1391 free_unref_page_prepare mm/page_alloc.c:3317 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3396 kvfree+0x42/0x50 mm/util.c:620 snd_seq_pool_done sound/core/seq/seq_memory.c:445 [inline] snd_seq_pool_done+0x166/0x200 sound/core/seq/seq_memory.c:423 snd_seq_pool_delete+0x45/0x70 sound/core/seq/seq_memory.c:488 seq_free_client1.part.0+0x151/0x260 sound/core/seq/seq_clientmgr.c:283 seq_free_client1 sound/core/seq/seq_clientmgr.c:273 [inline] seq_free_client+0x7b/0xf0 sound/core/seq/seq_clientmgr.c:301 snd_seq_release+0x4d/0xe0 sound/core/seq/seq_clientmgr.c:382 __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_fast_syscall_32+0x72/0xf0 arch/x86/entry/common.c:181 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Memory state around the buggy address: ffff888079217000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888079217080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888079217100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888079217180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888079217200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================