================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3e6f/0x54c0 kernel/locking/lockdep.c:4771 Read of size 8 at addr ffff888019765468 by task syz-executor.2/13614 CPU: 3 PID: 13614 Comm: syz-executor.2 Not tainted 5.12.0-rc8-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 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/0x2c6 mm/kasan/report.c:232 __kasan_report mm/kasan/report.c:399 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416 __lock_acquire+0x3e6f/0x54c0 kernel/locking/lockdep.c:4771 lock_acquire kernel/locking/lockdep.c:5511 [inline] lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5476 __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:140 exit_task_work include/linux/task_work.h:30 [inline] do_exit+0xbfc/0x2a60 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2150 kernel/signal.c:2781 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x148/0x250 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 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x466459 Code: Unable to access opcode bytes at RIP 0x46642f. RSP: 002b:00007fc43a4bd218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000056bf68 RCX: 0000000000466459 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68 RBP: 000000000056bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf6c R13: 00007ffce2e0ffdf R14: 00007fc43a4bd300 R15: 0000000000022000 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:427 [inline] ____kasan_kmalloc mm/kasan/common.c:506 [inline] ____kasan_kmalloc mm/kasan/common.c:465 [inline] __kasan_kmalloc+0x96/0xc0 mm/kasan/common.c:515 kasan_kmalloc include/linux/kasan.h:233 [inline] kmem_cache_alloc_trace+0x1f5/0x440 mm/slab.c:3570 kmalloc include/linux/slab.h:554 [inline] kzalloc include/linux/slab.h:684 [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:1226 do_initcall_level init/main.c:1299 [inline] do_initcalls init/main.c:1315 [inline] do_basic_setup init/main.c:1335 [inline] kernel_init_freeable+0x63e/0x6c2 init/main.c:1537 kernel_init+0xd/0x1b8 init/main.c:1424 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Freed by task 13597: 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+0xc7/0x100 mm/kasan/common.c:367 kasan_slab_free include/linux/kasan.h:199 [inline] __cache_free mm/slab.c:3440 [inline] kfree+0x104/0x2b0 mm/slab.c:3796 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:1807 [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:140 exit_task_work include/linux/task_work.h:30 [inline] do_exit+0xbfc/0x2a60 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2150 kernel/signal.c:2781 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x148/0x250 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 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff888019765000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1128 bytes inside of 2048-byte region [ffff888019765000, ffff888019765800) The buggy address belongs to the page: page:ffffea000065d940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x19765 flags: 0xfff00000000200(slab) raw: 00fff00000000200 ffffea000053a208 ffffea0000531888 ffff888010840800 raw: 0000000000000000 ffff888019765000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888019765300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888019765380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888019765400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888019765480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888019765500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================