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BUG: KASAN: slab-out-of-bounds in pfkey_msg2xfrm_state net/key/af_key.c:1227 [inline]
BUG: KASAN: slab-out-of-bounds in pfkey_add+0x1481/0x3230 net/key/af_key.c:1506
Read of size 480 at addr ffff8801b991b940 by task syz-executor5/6945

CPU: 1 PID: 6945 Comm: syz-executor5 Not tainted 4.9.107-gdb2c520 #49
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff880197c276e0[   55.492225] TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
 ffffffff81eb3da9 ffffea0006e64680 ffff8801b991b940
 0000000000000000 ffff8801b991bb00 ffff8801b991b900 ffff880197c27718
 ffffffff815679f9 ffff8801b991b940 00000000000001e0 0000000000000000
Call Trace:
 [<ffffffff81eb3da9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb3da9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff815679f9>] print_address_description+0x6c/0x234 mm/kasan/report.c:256
 [<ffffffff81567e03>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff81567e03>] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412
 [<ffffffff8153a8bf>] check_memory_region_inline mm/kasan/kasan.c:318 [inline]
 [<ffffffff8153a8bf>] check_memory_region+0x14f/0x1b0 mm/kasan/kasan.c:325
 [<ffffffff8153af03>] memcpy+0x23/0x50 mm/kasan/kasan.c:360
 [<ffffffff836af681>] pfkey_msg2xfrm_state net/key/af_key.c:1227 [inline]
 [<ffffffff836af681>] pfkey_add+0x1481/0x3230 net/key/af_key.c:1506
 [<ffffffff836a6e91>] pfkey_process+0x671/0x740 net/key/af_key.c:2834
 [<ffffffff836a86b6>] pfkey_sendmsg+0x346/0xae0 net/key/af_key.c:3678
 [<ffffffff83016fcc>] sock_sendmsg_nosec net/socket.c:635 [inline]
 [<ffffffff83016fcc>] sock_sendmsg+0xcc/0x110 net/socket.c:645
 [<ffffffff83018a6c>] ___sys_sendmsg+0x6fc/0x840 net/socket.c:1969
 [<ffffffff8301aad9>] __sys_sendmsg+0xd9/0x190 net/socket.c:2003
 [<ffffffff8301abbd>] SYSC_sendmsg net/socket.c:2014 [inline]
 [<ffffffff8301abbd>] SyS_sendmsg+0x2d/0x50 net/socket.c:2010
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f9b13>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Allocated by task 6945:
 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+0xc7/0xe0 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+0xdc/0x2b0 mm/slub.c:4232
 __kmalloc_reserve.isra.37+0x33/0xc0 net/core/skbuff.c:138
 __alloc_skb+0x11a/0x600 net/core/skbuff.c:231
 alloc_skb include/linux/skbuff.h:919 [inline]
 pfkey_sendmsg+0xfe/0xae0 net/key/af_key.c:3665
 sock_sendmsg_nosec net/socket.c:635 [inline]
 sock_sendmsg+0xcc/0x110 net/socket.c:645
 ___sys_sendmsg+0x6fc/0x840 net/socket.c:1969
 __sys_sendmsg+0xd9/0x190 net/socket.c:2003
 SYSC_sendmsg net/socket.c:2014 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2010
 do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Freed by task 5685:
 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+0xfb/0x310 mm/slub.c:3878
 skb_free_head+0x8b/0xb0 net/core/skbuff.c:580
 skb_release_data+0x329/0x400 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
 netlink_unicast_kernel net/netlink/af_netlink.c:1279 [inline]
 netlink_unicast+0x4e0/0x6f0 net/netlink/af_netlink.c:1304
 netlink_sendmsg+0x795/0xc30 net/netlink/af_netlink.c:1852
 sock_sendmsg_nosec net/socket.c:635 [inline]
 sock_sendmsg+0xcc/0x110 net/socket.c:645
 ___sys_sendmsg+0x6fc/0x840 net/socket.c:1969
 __sys_sendmsg+0xd9/0x190 net/socket.c:2003
 SYSC_sendmsg net/socket.c:2014 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2010
 do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 entry_SYSCALL_64_after_swapgs+0x5d/0xdb

The buggy address belongs to the object at ffff8801b991b900
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 64 bytes inside of
 512-byte region [ffff8801b991b900, ffff8801b991bb00)
The buggy address belongs to the page:
page:ffffea0006e64680 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:
 ffff8801b991ba00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801b991ba80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801b991bb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff8801b991bb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801b991bc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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