================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3c88/0x5230 kernel/locking/lockdep.c:4772 Read of size 8 at addr ffff8881431f7468 by task syz-executor.5/25712 CPU: 1 PID: 25712 Comm: syz-executor.5 Not tainted 5.12.0-rc7-next-20210415-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:436 __lock_acquire+0x3c88/0x5230 kernel/locking/lockdep.c:4772 lock_acquire kernel/locking/lockdep.c:5512 [inline] lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5477 __raw_write_lock include/linux/rwlock_api_smp.h:210 [inline] _raw_write_lock+0x2a/0x40 kernel/locking/spinlock.c:295 nfc_llcp_sock_unlink+0x1d/0x1c0 net/nfc/llcp_core.c:32 llcp_sock_release+0x286/0x580 net/nfc/llcp_sock.c:640 __sock_release+0xcd/0x280 net/socket.c:599 sock_close+0x18/0x20 net/socket.c:1258 __fput+0x288/0x920 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:174 [inline] exit_to_user_mode_prepare+0x272/0x280 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:57 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x41926b Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffdef222870 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 000000000041926b RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000006 RBP: 0000000000000001 R08: 0000000000000000 R09: 00000000000007b2 R10: 00000000f18ee7b6 R11: 0000000000000293 R12: 000000000056c9e0 R13: 000000000056c9e0 R14: 000000000056bf60 R15: 00000000000d4c98 Allocated by task 1: 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:428 [inline] ____kasan_kmalloc mm/kasan/common.c:507 [inline] ____kasan_kmalloc mm/kasan/common.c:466 [inline] __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:516 kmalloc include/linux/slab.h:558 [inline] kzalloc include/linux/slab.h:688 [inline] nfc_llcp_register_device+0x45/0x9d0 net/nfc/llcp_core.c:1572 nfc_register_device+0x6d/0x360 net/nfc/core.c:1124 nfcsim_device_new+0x345/0x5c1 drivers/nfc/nfcsim.c:408 nfcsim_init+0x71/0x14d drivers/nfc/nfcsim.c:455 do_one_initcall+0x103/0x650 init/main.c:1251 do_initcall_level init/main.c:1324 [inline] do_initcalls init/main.c:1340 [inline] do_basic_setup init/main.c:1360 [inline] kernel_init_freeable+0x63e/0x6c7 init/main.c:1562 kernel_init+0xd/0x1c0 init/main.c:1449 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Freed by task 25713: 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:357 ____kasan_slab_free mm/kasan/common.c:360 [inline] ____kasan_slab_free mm/kasan/common.c:325 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:368 kasan_slab_free include/linux/kasan.h:212 [inline] slab_free_hook mm/slub.c:1593 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1618 slab_free mm/slub.c:3178 [inline] kfree+0xe5/0x7f0 mm/slub.c:4245 local_release net/nfc/llcp_core.c:175 [inline] kref_put include/linux/kref.h:65 [inline] nfc_llcp_local_put net/nfc/llcp_core.c:183 [inline] nfc_llcp_local_put+0x194/0x200 net/nfc/llcp_core.c:178 llcp_sock_destruct+0x81/0x150 net/nfc/llcp_sock.c:950 __sk_destruct+0x4b/0x900 net/core/sock.c:1795 sk_destruct+0xbd/0xe0 net/core/sock.c:1839 __sk_free+0xef/0x3d0 net/core/sock.c:1850 sk_free+0x78/0xa0 net/core/sock.c:1861 sock_put include/net/sock.h:1813 [inline] llcp_sock_release+0x3c9/0x580 net/nfc/llcp_sock.c:644 __sock_release+0xcd/0x280 net/socket.c:599 sock_close+0x18/0x20 net/socket.c:1258 __fput+0x288/0x920 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:174 [inline] exit_to_user_mode_prepare+0x272/0x280 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:57 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff8881431f7000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1128 bytes inside of 2048-byte region [ffff8881431f7000, ffff8881431f7800) The buggy address belongs to the page: page:ffffea00050c7c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1431f0 head:ffffea00050c7c00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x57ff00000010200(slab|head|node=1|zone=2|lastcpupid=0x7ff) raw: 057ff00000010200 dead000000000100 dead000000000122 ffff888010c42000 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881431f7300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881431f7380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881431f7400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881431f7480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881431f7500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================