RBP: 000000000072bea0 R08: 0000000020000940 R09: 0000000000000000
R10: 0000000020000900 R11: 0000000000000246 R12: 0000000000000013
R13: 0000000000000051 R14: 00000000006f3838 R15: 0000000000000029
binder: 575 RLIMIT_NICE not set
==================================================================
BUG: KASAN: use-after-free in alloc_pid+0x9e8/0xa50 kernel/pid.c:236
Read of size 4 at addr ffff8801b73d42a8 by task syz-executor7/568

CPU: 0 PID: 568 Comm: syz-executor7 Not tainted 4.16.0+ #17
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+0x1b9/0x294 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0xac/0x2f5 mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 alloc_pid+0x9e8/0xa50 kernel/pid.c:236
 copy_process.part.38+0x36bf/0x6ee0 kernel/fork.c:1809
 copy_process kernel/fork.c:1608 [inline]
 _do_fork+0x291/0x12a0 kernel/fork.c:2089
 SYSC_clone kernel/fork.c:2196 [inline]
 SyS_clone+0x37/0x50 kernel/fork.c:2190
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x455259
RSP: 002b:00007fa2adbe2c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fa2adbe36d4 RCX: 0000000000455259
RDX: 00000000200008c0 RSI: 0000000020000800 RDI: 000000002000c100
RBP: 000000000072bea0 R08: 0000000020000940 R09: 0000000000000000
R10: 0000000020000900 R11: 0000000000000246 R12: 0000000000000013
R13: 0000000000000051 R14: 00000000006f3838 R15: 0000000000000029

Allocated by task 568:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554
 kmem_cache_zalloc include/linux/slab.h:691 [inline]
 create_pid_namespace kernel/pid_namespace.c:97 [inline]
 copy_pid_ns+0x2c3/0xb40 kernel/pid_namespace.c:156
 create_new_namespaces+0x48a/0x8f0 kernel/nsproxy.c:94
 copy_namespaces+0x3f7/0x4c0 kernel/nsproxy.c:165
 copy_process.part.38+0x353a/0x6ee0 kernel/fork.c:1798
 copy_process kernel/fork.c:1608 [inline]
 _do_fork+0x291/0x12a0 kernel/fork.c:2089
 SYSC_clone kernel/fork.c:2196 [inline]
 SyS_clone+0x37/0x50 kernel/fork.c:2190
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 575:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kmem_cache_free+0x86/0x2d0 mm/slab.c:3756
 delayed_free_pidns+0xaa/0xe0 kernel/pid_namespace.c:138
 __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+0x941/0x15f0 kernel/rcu/tree.c:2914
 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285

The buggy address belongs to the object at ffff8801b73d4260
 which belongs to the cache pid_namespace of size 240
The buggy address is located 72 bytes inside of
 240-byte region [ffff8801b73d4260, ffff8801b73d4350)
The buggy address belongs to the page:
page:ffffea0006dcf500 count:1 mapcount:0 mapping:ffff8801b73d4000 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801b73d4000 0000000000000000 000000010000000d
raw: ffffea00065c88a0 ffff8801d40af648 ffff8801d4681780 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b73d4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801b73d4200: fb fb fb fb fc fc fc fc fc fc fc fc fb fb fb fb
>ffff8801b73d4280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff8801b73d4300: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc
 ffff8801b73d4380: fc fc fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================