RBP: 000000000075bf20 R08: 00000000200002c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb110e566d4 R13: 00000000004bfce6 R14: 00000000004d1a58 R15: 0000000000000003 refcount_t: underflow; use-after-free. ------------[ cut here ]------------ WARNING: CPU: 1 PID: 1642 at lib/refcount.c:187 refcount_sub_and_test lib/refcount.c:187 [inline] WARNING: CPU: 1 PID: 1642 at lib/refcount.c:187 refcount_sub_and_test.cold+0x18/0x22 lib/refcount.c:177 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 1642 Comm: syz-executor.4 Not tainted 4.14.138 #34 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x138/0x19c lib/dump_stack.c:53 panic+0x1f2/0x426 kernel/panic.c:182 __warn.cold+0x2f/0x36 kernel/panic.c:546 report_bug+0x216/0x254 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:177 [inline] fixup_bug arch/x86/kernel/traps.c:172 [inline] do_error_trap+0x1bb/0x310 arch/x86/kernel/traps.c:295 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:963 RIP: 0010:refcount_sub_and_test lib/refcount.c:187 [inline] RIP: 0010:refcount_sub_and_test.cold+0x18/0x22 lib/refcount.c:177 RSP: 0018:ffff888067dc7af8 EFLAGS: 00010286 RAX: 0000000000000026 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff814b2ab5 RDI: ffffed100cfb8f55 RBP: ffff888067dc7b20 R08: 0000000000000026 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888091ed93b0 R13: 0000000000000001 R14: 00000000ffffffff R15: 0000000020886100 refcount_dec_and_test+0x1b/0x20 lib/refcount.c:212 kref_put include/linux/kref.h:69 [inline] put_pid_ns+0x55/0x110 kernel/pid_namespace.c:203 free_nsproxy+0x103/0x200 kernel/nsproxy.c:182 switch_task_namespaces+0x98/0xb0 kernel/nsproxy.c:229 exit_task_namespaces+0x18/0x20 kernel/nsproxy.c:234 copy_process.part.0+0x3b59/0x6a00 kernel/fork.c:1986 copy_process kernel/fork.c:1595 [inline] _do_fork+0x19e/0xce0 kernel/fork.c:2085 SYSC_clone kernel/fork.c:2195 [inline] SyS_clone+0x37/0x50 kernel/fork.c:2189 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459829 RSP: 002b:00007fb110e55c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fb110e55c90 RCX: 0000000000459829 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020886100 RBP: 000000000075bf20 R08: 00000000200002c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb110e566d4 R13: 00000000004bfce6 R14: 00000000004d1a58 R15: 0000000000000003 Kernel Offset: disabled Rebooting in 86400 seconds..