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BUG: KASAN: use-after-free in __lock_acquire+0x2cb4/0x3ff0 kernel/locking/lockdep.c:3295
Read of size 8 at addr ffff88806570b420 by task syz-executor.1/17024

CPU: 0 PID: 17024 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
 __lock_acquire+0x2cb4/0x3ff0 kernel/locking/lockdep.c:3295
 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
 _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:168
 spin_lock_bh include/linux/spinlock.h:334 [inline]
 lock_sock_nested+0x3b/0x110 net/core/sock.c:2884
 lock_sock include/net/sock.h:1512 [inline]
 nr_accept+0x1df/0x630 net/netrom/af_netrom.c:808
 __sys_accept4+0x322/0x5f0 net/socket.c:1701
 __do_sys_accept net/socket.c:1742 [inline]
 __se_sys_accept net/socket.c:1739 [inline]
 __x64_sys_accept+0x71/0xb0 net/socket.c:1739
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f8dd2bbf0f9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8dd1131168 EFLAGS: 00000246 ORIG_RAX: 000000000000002b
RAX: ffffffffffffffda RBX: 00007f8dd2cdef80 RCX: 00007f8dd2bbf0f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007f8dd2c1aae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe3913c00f R14: 00007f8dd1131300 R15: 0000000000022000

Allocated by task 17024:
 __do_kmalloc mm/slab.c:3727 [inline]
 __kmalloc+0x15a/0x3c0 mm/slab.c:3736
 kmalloc include/linux/slab.h:520 [inline]
 sk_prot_alloc+0x1e2/0x2d0 net/core/sock.c:1483
 sk_alloc+0x36/0xec0 net/core/sock.c:1537
 nr_create+0xb2/0x5d0 net/netrom/af_netrom.c:436
 __sock_create+0x3d8/0x740 net/socket.c:1365
 sock_create net/socket.c:1416 [inline]
 __sys_socket+0xef/0x200 net/socket.c:1458
 __do_sys_socket net/socket.c:1467 [inline]
 __se_sys_socket net/socket.c:1465 [inline]
 __x64_sys_socket+0x6f/0xb0 net/socket.c:1465
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 17074:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 sk_prot_free net/core/sock.c:1520 [inline]
 __sk_destruct+0x684/0x8a0 net/core/sock.c:1602
 sk_destruct net/core/sock.c:1617 [inline]
 __sk_free+0x165/0x3b0 net/core/sock.c:1628
 sk_free+0x3b/0x50 net/core/sock.c:1639
 sock_put include/net/sock.h:1713 [inline]
 nr_heartbeat_expiry+0x34f/0x3b0 net/netrom/nr_timer.c:151
 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338
 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375
 __run_timers kernel/time/timer.c:1696 [inline]
 run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709
 __do_softirq+0x265/0x980 kernel/softirq.c:292

The buggy address belongs to the object at ffff88806570b380
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 160 bytes inside of
 2048-byte region [ffff88806570b380, ffff88806570bb80)
The buggy address belongs to the page:
page:ffffea000195c280 count:1 mapcount:0 mapping:ffff88813bff0c40 index:0x0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffffea00024aad88 ffffea00024a6608 ffff88813bff0c40
raw: 0000000000000000 ffff88806570a280 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88806570b300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88806570b380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88806570b400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff88806570b480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806570b500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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