------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 18596 at lib/refcount.c:28 refcount_warn_saturate+0x1dc/0x1f0 lib/refcount.c:28 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 18596 Comm: syz-executor.1 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 panic+0x2e3/0x75c kernel/panic.c:221 __warn.cold+0x2f/0x3e kernel/panic.c:582 report_bug+0x289/0x300 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:174 [inline] fixup_bug arch/x86/kernel/traps.c:169 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027 RIP: 0010:refcount_warn_saturate+0x1dc/0x1f0 lib/refcount.c:28 Code: e9 d8 fe ff ff 48 89 df e8 31 65 25 fe e9 85 fe ff ff e8 07 37 e8 fd 48 c7 c7 60 53 4f 88 c6 05 7d b6 a5 06 01 e8 73 eb b8 fd <0f> 0b e9 ac fe ff ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 55 48 RSP: 0018:ffff8880987c7d50 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 000000000000ea73 RSI: ffffffff815e4316 RDI: ffffed10130f8f9c RBP: ffff8880987c7d60 R08: ffff8880a3864540 R09: ffffed1015d245c9 R10: ffffed1015d245c8 R11: ffff8880ae922e47 R12: 0000000000000003 R13: 0000000000000000 R14: ffff888097541380 R15: ffff8880934d1598 refcount_sub_and_test include/linux/refcount.h:261 [inline] refcount_dec_and_test include/linux/refcount.h:281 [inline] sock_put include/net/sock.h:1728 [inline] smc_release+0x445/0x520 net/smc/af_smc.c:202 __sock_release+0xce/0x280 net/socket.c:591 sock_close+0x1e/0x30 net/socket.c:1269 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x676/0x790 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a679 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff8ee8e3c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffff8d RBX: 0000000000000003 RCX: 000000000045a679 RDX: 0000000000000010 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff8ee8e46d4 R13: 00000000004c0e08 R14: 00000000004d4880 R15: 00000000ffffffff Kernel Offset: disabled Rebooting in 86400 seconds..