audit: type=1400 audit(1513757241.623:16): avc:  denied  { net_admin } for  pid=3411 comm="syz-executor1" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:344 [inline]
BUG: KASAN: slab-out-of-bounds in sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161
Write of size 192 at addr ffff8801cee168fc by task syz-executor2/3444

CPU: 1 PID: 3444 Comm: syz-executor2 Not tainted 4.15.0-rc4+ #229
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
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
 memcpy+0x37/0x50 mm/kasan/kasan.c:303
 memcpy include/linux/string.h:344 [inline]
 sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161
 crypto_shash_update+0xcb/0x220 crypto/shash.c:110
 hmac_update+0x7e/0xa0 crypto/hmac.c:122
 crypto_shash_update+0xcb/0x220 crypto/shash.c:110
 kdf_ctr security/keys/dh.c:181 [inline]
 keyctl_dh_compute_kdf security/keys/dh.c:226 [inline]
 __keyctl_dh_compute+0x163f/0x1970 security/keys/dh.c:398
 keyctl_dh_compute+0xac/0xf3 security/keys/dh.c:434
 SYSC_keyctl security/keys/keyctl.c:1741 [inline]
 SyS_keyctl+0x72/0x2c0 security/keys/keyctl.c:1637
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452a09
RSP: 002b:00007f727db6ac58 EFLAGS: 00000212 ORIG_RAX: 00000000000000fa
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452a09
RDX: 00000000205cd000 RSI: 0000000020a34ff4 RDI: 0000000000000017
RBP: 0000000000000015 R08: 0000000020550000 R09: 0000000000000000
R10: 0000000000000030 R11: 0000000000000212 R12: 00000000006ed298
R13: 00000000ffffffff R14: 00007f727db6b6d4 R15: 0000000000000000

Allocated by task 3444:
 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+0x162/0x760 mm/slab.c:3717
 kmalloc include/linux/slab.h:504 [inline]
 kdf_alloc security/keys/dh.c:111 [inline]
 __keyctl_dh_compute+0x2a8/0x1970 security/keys/dh.c:288
 keyctl_dh_compute+0xac/0xf3 security/keys/dh.c:434
 SYSC_keyctl security/keys/keyctl.c:1741 [inline]
 SyS_keyctl+0x72/0x2c0 security/keys/keyctl.c:1637
 entry_SYSCALL_64_fastpath+0x1f/0x96

Freed by task 1602:
 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+0xca/0x250 mm/slab.c:3803
 skb_free_head+0x74/0xb0 net/core/skbuff.c:550
 skb_release_data+0x58c/0x790 net/core/skbuff.c:570
 skb_release_all+0x4a/0x60 net/core/skbuff.c:627
 __kfree_skb net/core/skbuff.c:641 [inline]
 consume_skb+0x153/0x490 net/core/skbuff.c:701
 skb_free_datagram+0x1a/0xe0 net/core/datagram.c:331
 netlink_recvmsg+0x5c6/0x1300 net/netlink/af_netlink.c:1943
 sock_recvmsg_nosec net/socket.c:809 [inline]
 sock_recvmsg+0xc9/0x110 net/socket.c:816
 ___sys_recvmsg+0x295/0x620 net/socket.c:2185
 __sys_recvmsg+0xe2/0x210 net/socket.c:2230
 SYSC_recvmsg net/socket.c:2242 [inline]
 SyS_recvmsg+0x2d/0x50 net/socket.c:2237
 entry_SYSCALL_64_fastpath+0x1f/0x96

The buggy address belongs to the object at ffff8801cee16800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 252 bytes inside of
 512-byte region [ffff8801cee16800, ffff8801cee16a00)
The buggy address belongs to the page:
page:0000000006b7d507 count:1 mapcount:0 mapping:000000000a3c35b0 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801cee16080 0000000000000000 0000000100000006
raw: ffffea0007276ee0 ffffea0007214260 ffff8801db000940 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801cee16880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801cee16900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801cee16980: 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                      ^
 ffff8801cee16a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801cee16a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================