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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 6144 at addr ffff8801c8708018 by task syzkaller473739/3331

CPU: 0 PID: 3331 Comm: syzkaller473739 Not tainted 4.9.71-g319c8e1 #111
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801c84b7788 ffffffff81d91639 ffffea000721c200 ffff8801c8708018
 0000000000000000 ffff8801c8708200 ffff8801c84b79c8 ffff8801c84b77c0
 ffffffff8153af43 ffff8801c8708018 0000000000001800 0000000000000000
Call Trace:
 [<ffffffff81d91639>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d91639>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8153af43>] print_address_description+0x73/0x280 mm/kasan/report.c:252
 [<ffffffff8153b465>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8153b465>] kasan_report+0x275/0x360 mm/kasan/report.c:408
 [<ffffffff81539e77>] check_memory_region_inline mm/kasan/kasan.c:318 [inline]
 [<ffffffff81539e77>] check_memory_region+0x137/0x190 mm/kasan/kasan.c:325
 [<ffffffff8153a3b3>] memcpy+0x23/0x50 mm/kasan/kasan.c:360
 [<ffffffff8356ddb2>] pfkey_msg2xfrm_state net/key/af_key.c:1180 [inline]
 [<ffffffff8356ddb2>] pfkey_add+0x2702/0x3470 net/key/af_key.c:1498
 [<ffffffff8356510e>] pfkey_process+0x61e/0x730 net/key/af_key.c:2826
 [<ffffffff835669b9>] pfkey_sendmsg+0x3a9/0x760 net/key/af_key.c:3670
 [<ffffffff82ed0baa>] sock_sendmsg_nosec net/socket.c:635 [inline]
 [<ffffffff82ed0baa>] sock_sendmsg+0xca/0x110 net/socket.c:645
 [<ffffffff82ed27a1>] ___sys_sendmsg+0x6d1/0x7e0 net/socket.c:1969
 [<ffffffff82ed47d6>] __sys_sendmsg+0xd6/0x190 net/socket.c:2003
 [<ffffffff82ed48bd>] SYSC_sendmsg net/socket.c:2014 [inline]
 [<ffffffff82ed48bd>] SyS_sendmsg+0x2d/0x50 net/socket.c:2010
 [<ffffffff838ab505>] entry_SYSCALL_64_fastpath+0x23/0xc6

Allocated by task 3331:
 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
 SYSC_sendmsg net/socket.c:2014 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2010
 entry_SYSCALL_64_fastpath+0x23/0xc6

Freed by task 1763:
 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+0xf0/0x2f0 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 net/core/skbuff.c:684 [inline]
 consume_skb+0xc6/0x340 net/core/skbuff.c:757
 skb_free_datagram+0x1a/0xe0 net/core/datagram.c:299
 unix_dgram_recvmsg+0x983/0xf90 net/unix/af_unix.c:2202
 sock_recvmsg_nosec net/socket.c:737 [inline]
 sock_recvmsg+0xc9/0x110 net/socket.c:744
 SYSC_recvfrom+0x1fc/0x330 net/socket.c:1722
 SyS_recvfrom+0x40/0x50 net/socket.c:1694
 entry_SYSCALL_64_fastpath+0x23/0xc6

The buggy address belongs to the object at ffff8801c8708000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 24 bytes inside of
 512-byte region [ffff8801c8708000, ffff8801c8708200)
The buggy address belongs to the page:
page:ffffea000721c200 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:
 ffff8801c8708100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801c8708180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801c8708200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff8801c8708280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801c8708300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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