TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
device bond0 entered promiscuous mode
==================================================================
BUG: KASAN: use-after-free in alloc_pid+0x9b6/0xa10 kernel/pid.c:236
Read of size 4 at addr ffff8801b6067418 by task syz-executor2/24980

CPU: 1 PID: 24980 Comm: syz-executor2 Not tainted 4.16.0+ #288
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+0x1a7/0x27d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23c/0x360 mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 alloc_pid+0x9b6/0xa10 kernel/pid.c:236
 copy_process.part.38+0x274c/0x6140 kernel/fork.c:1807
 copy_process kernel/fork.c:1606 [inline]
 _do_fork+0x1f7/0xfa0 kernel/fork.c:2087
 C_SYSC_x86_clone arch/x86/ia32/sys_ia32.c:240 [inline]
 compat_SyS_x86_clone+0x3b/0x50 arch/x86/ia32/sys_ia32.c:236
 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline]
 do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7fc0c99
RSP: 002b:00000000f5fbc0ac EFLAGS: 00000282 ORIG_RAX: 0000000000000078
RAX: ffffffffffffffda RBX: 00000000201043f9 RCX: 0000000020e02000
RDX: 000000002006fffc RSI: 0000000020000180 RDI: 0000000020000080
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 24980:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:552
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3542
 kmem_cache_zalloc include/linux/slab.h:691 [inline]
 create_pid_namespace kernel/pid_namespace.c:116 [inline]
 copy_pid_ns+0x257/0xca0 kernel/pid_namespace.c:175
 create_new_namespaces+0x314/0x890 kernel/nsproxy.c:94
 copy_namespaces+0x34d/0x400 kernel/nsproxy.c:165
 copy_process.part.38+0x23c1/0x6140 kernel/fork.c:1796
 copy_process kernel/fork.c:1606 [inline]
 _do_fork+0x1f7/0xfa0 kernel/fork.c:2087
 C_SYSC_x86_clone arch/x86/ia32/sys_ia32.c:240 [inline]
 compat_SyS_x86_clone+0x3b/0x50 arch/x86/ia32/sys_ia32.c:236
 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline]
 do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

Freed by task 24977:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527
 __cache_free mm/slab.c:3486 [inline]
 kmem_cache_free+0x83/0x2a0 mm/slab.c:3744
 delayed_free_pidns+0x97/0xc0 kernel/pid_namespace.c:157
 __rcu_reclaim kernel/rcu/rcu.h:178 [inline]
 rcu_do_batch kernel/rcu/tree.c:2675 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2930 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2897 [inline]
 rcu_process_callbacks+0xd6c/0x17b0 kernel/rcu/tree.c:2914
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285

The buggy address belongs to the object at ffff8801b60673d0
 which belongs to the cache pid_namespace of size 240
The buggy address is located 72 bytes inside of
 240-byte region [ffff8801b60673d0, ffff8801b60674c0)
The buggy address belongs to the page:
page:ffffea0006d819c0 count:1 mapcount:0 mapping:ffff8801b6067040 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801b6067040 0000000000000000 000000010000000d
raw: ffffea00066304a0 ffff8801d4000748 ffff8801d4e69780 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b6067300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801b6067380: fc fc fc fc fc fc fc fc fc fc fb fb fb fb fb fb
>ffff8801b6067400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff8801b6067480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8801b6067500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================