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nla_parse: 4 callbacks suppressed
netlink: 3736 bytes leftover after parsing attributes in process `syz-executor2'.
BUG: KASAN: use-after-free in erspan_xmit+0x22d4/0x2430 net/ipv4/ip_gre.c:735
Read of size 2 at addr ffff8801d2e2428b by task syz-executor5/13513
netlink: 3736 bytes leftover after parsing attributes in process `syz-executor2'.

CPU: 1 PID: 13513 Comm: syz-executor5 Not tainted 4.15.0-rc8+ #203
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+0x194/0x257 lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:440
 erspan_xmit+0x22d4/0x2430 net/ipv4/ip_gre.c:735
 __netdev_start_xmit include/linux/netdevice.h:4053 [inline]
 netdev_start_xmit include/linux/netdevice.h:4062 [inline]
 packet_direct_xmit+0x3ad/0x790 net/packet/af_packet.c:267
 packet_snd net/packet/af_packet.c:2944 [inline]
 packet_sendmsg+0x3aed/0x60b0 net/packet/af_packet.c:2969
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:640
 SYSC_sendto+0x361/0x5c0 net/socket.c:1721
 SyS_sendto+0x40/0x50 net/socket.c:1689
 entry_SYSCALL_64_fastpath+0x29/0xa0
RIP: 0033:0x452ef9
RSP: 002b:00007f75f300dc58 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ef9
RDX: 0000000000000000 RSI: 0000000020003fd9 RDI: 0000000000000013
RBP: 0000000000000374 R08: 0000000020008000 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f4380
R13: 00000000ffffffff R14: 00007f75f300e6d4 R15: 0000000000000000

Allocated by task 13328:
 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:551
 __do_kmalloc mm/slab.c:3708 [inline]
 __kmalloc_track_caller+0x15e/0x760 mm/slab.c:3723
 kmemdup+0x24/0x50 mm/util.c:118
 kmemdup include/linux/string.h:417 [inline]
 selinux_cred_prepare+0x43/0xa0 security/selinux/hooks.c:3828
 security_prepare_creds+0x7d/0xb0 security/security.c:1000
 prepare_creds+0x2b1/0x360 kernel/cred.c:278
 SYSC_faccessat fs/open.c:365 [inline]
 SyS_faccessat fs/open.c:353 [inline]
 SYSC_access fs/open.c:431 [inline]
 SyS_access+0x8f/0x6a0 fs/open.c:429
 entry_SYSCALL_64_fastpath+0x29/0xa0

Freed by task 13313:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3488 [inline]
 kfree+0xd6/0x260 mm/slab.c:3803
 selinux_cred_free+0x48/0x70 security/selinux/hooks.c:3814
 security_cred_free+0x48/0x80 security/security.c:995
 put_cred_rcu+0x106/0x400 kernel/cred.c:117
 __rcu_reclaim kernel/rcu/rcu.h:195 [inline]
 rcu_do_batch kernel/rcu/tree.c:2758 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:3012 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2979 [inline]
 rcu_process_callbacks+0xd6c/0x17f0 kernel/rcu/tree.c:2996
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285

The buggy address belongs to the object at ffff8801d2e24280
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 11 bytes inside of
 32-byte region [ffff8801d2e24280, ffff8801d2e242a0)
The buggy address belongs to the page:
page:ffffea00074b8900 count:1 mapcount:0 mapping:ffff8801d2e24000 index:0xffff8801d2e24fc1
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801d2e24000 ffff8801d2e24fc1 000000010000003f
raw: ffffea00075fe220 ffffea00073f5620 ffff8801dac001c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d2e24180: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8801d2e24200: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
>ffff8801d2e24280: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
                      ^
 ffff8801d2e24300: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8801d2e24380: fb fb fb fb fc fc fc fc 00 02 fc fc fc fc fc fc
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