==================================================================
BUG: KASAN: slab-out-of-bounds in pfkey_msg2xfrm_state net/key/af_key.c:1180 [inline]
BUG: KASAN: slab-out-of-bounds in pfkey_add+0x2702/0x3470 net/key/af_key.c:1498
Read of size 8192 at addr ffff8801c8f8a518 by task syzkaller346979/3325

CPU: 0 PID: 3325 Comm: syzkaller346979 Not tainted 4.9.76-g9154940 #20
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801c84f7718 ffffffff81d93149 ffffea000723e280 ffff8801c8f8a518
 0000000000000000 ffff8801c8f8a700 ffff8801c84f7958 ffff8801c84f7750
 ffffffff8153cb43 ffff8801c8f8a518 0000000000002000 0000000000000000
Call Trace:
 [<ffffffff81d93149>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d93149>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8153cb43>] print_address_description+0x73/0x280 mm/kasan/report.c:252
 [<ffffffff8153d065>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8153d065>] kasan_report+0x275/0x360 mm/kasan/report.c:408
 [<ffffffff8153ba77>] check_memory_region_inline mm/kasan/kasan.c:318 [inline]
 [<ffffffff8153ba77>] check_memory_region+0x137/0x190 mm/kasan/kasan.c:325
 [<ffffffff8153bfb3>] memcpy+0x23/0x50 mm/kasan/kasan.c:360
 [<ffffffff83573882>] pfkey_msg2xfrm_state net/key/af_key.c:1180 [inline]
 [<ffffffff83573882>] pfkey_add+0x2702/0x3470 net/key/af_key.c:1498
 [<ffffffff8356abde>] pfkey_process+0x61e/0x730 net/key/af_key.c:2826
 [<ffffffff8356c489>] pfkey_sendmsg+0x3a9/0x760 net/key/af_key.c:3670
 [<ffffffff82ed5baa>] sock_sendmsg_nosec net/socket.c:635 [inline]
 [<ffffffff82ed5baa>] sock_sendmsg+0xca/0x110 net/socket.c:645
 [<ffffffff82ed77a1>] ___sys_sendmsg+0x6d1/0x7e0 net/socket.c:1969
 [<ffffffff82ed97d6>] __sys_sendmsg+0xd6/0x190 net/socket.c:2003
 [<ffffffff82fdbeba>] C_SYSC_sendmsg net/compat.c:734 [inline]
 [<ffffffff82fdbeba>] compat_SyS_sendmsg+0x2a/0x40 net/compat.c:732
 [<ffffffff81006fc7>] do_syscall_32_irqs_on arch/x86/entry/common.c:322 [inline]
 [<ffffffff81006fc7>] do_fast_syscall_32+0x2f7/0x890 arch/x86/entry/common.c:384
 [<ffffffff838b2334>] entry_SYSENTER_compat+0x74/0x83 arch/x86/entry/entry_64_compat.S:127

Allocated by task 3325:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
 save_stack+0x43/0xd0 mm/kasan/kasan.c:505
 set_track mm/kasan/kasan.c:517 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:609
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:547
 slab_post_alloc_hook mm/slab.h:417 [inline]
 slab_alloc_node mm/slub.c:2715 [inline]
 slab_alloc mm/slub.c:2723 [inline]
 __kmalloc_track_caller+0xda/0x2b0 mm/slub.c:4232
 __kmalloc_reserve.isra.37+0x33/0xc0 net/core/skbuff.c:138
 __alloc_skb+0x119/0x600 net/core/skbuff.c:231
 alloc_skb include/linux/skbuff.h:919 [inline]
 pfkey_sendmsg+0x135/0x760 net/key/af_key.c:3657
 sock_sendmsg_nosec net/socket.c:635 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:645
 ___sys_sendmsg+0x6d1/0x7e0 net/socket.c:1969
 __sys_sendmsg+0xd6/0x190 net/socket.c:2003
 C_SYSC_sendmsg net/compat.c:734 [inline]
 compat_SyS_sendmsg+0x2a/0x40 net/compat.c:732
 do_syscall_32_irqs_on arch/x86/entry/common.c:322 [inline]
 do_fast_syscall_32+0x2f7/0x890 arch/x86/entry/common.c:384
 entry_SYSENTER_compat+0x74/0x83 arch/x86/entry/entry_64_compat.S:127

Freed by task 1801:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
 save_stack+0x43/0xd0 mm/kasan/kasan.c:505
 set_track mm/kasan/kasan.c:517 [inline]
 kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:582
 slab_free_hook mm/slub.c:1355 [inline]
 slab_free_freelist_hook mm/slub.c:1377 [inline]
 slab_free mm/slub.c:2958 [inline]
 kfree+0x103/0x300 mm/slub.c:3878
 skb_free_head+0x74/0xb0 net/core/skbuff.c:580
 skb_release_data+0x315/0x3f0 net/core/skbuff.c:611
 skb_release_all+0x4a/0x60 net/core/skbuff.c:670
 __kfree_skb+0x15/0x20 net/core/skbuff.c:684
 kfree_skb+0xcc/0x330 net/core/skbuff.c:705
 unix_stream_connect+0x722/0x1160 net/unix/af_unix.c:1371
 SYSC_connect+0x1b6/0x310 net/socket.c:1562
 SyS_connect+0x24/0x30 net/socket.c:1543
 entry_SYSCALL_64_fastpath+0x23/0xe2

The buggy address belongs to the object at ffff8801c8f8a500
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 24 bytes inside of
 512-byte region [ffff8801c8f8a500, ffff8801c8f8a700)
The buggy address belongs to the page:
page:ffffea000723e280 count:1 mapcount:0 mapping:          (null) index:0x0 compound_mapcount: 0
flags: 0x8000000000004080(slab|head)
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c8f8a600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801c8f8a680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801c8f8a700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff8801c8f8a780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801c8f8a800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================