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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 206 at addr ffff8801cfbcd3bc by task syz-executor6/23889

CPU: 0 PID: 23889 Comm: syz-executor6 Not tainted 4.15.0-rc4-mm1+ #49
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:256
 kasan_report_error mm/kasan/report.c:355 [inline]
 kasan_report+0x23b/0x360 mm/kasan/report.c:413
 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+0xda/0x240 crypto/shash.c:110
 hmac_update+0x7e/0xa0 crypto/hmac.c:122
 crypto_shash_update+0xda/0x240 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+0x160f/0x1990 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: 0033:0x452ac9
RSP: 002b:00007faa48c8fc58 EFLAGS: 00000212 ORIG_RAX: 00000000000000fa
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ac9
RDX: 00000000205cd000 RSI: 00000000204c8ff4 RDI: 0000000000000017
RBP: 0000000000000260 R08: 0000000020457fc8 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000212 R12: 00000000006f09a0
R13: 00000000ffffffff R14: 00007faa48c906d4 R15: 0000000000000000

Allocated by task 23889:
 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:3705 [inline]
 __kmalloc+0x162/0x760 mm/slab.c:3714
 kmalloc include/linux/slab.h:521 [inline]
 kdf_alloc security/keys/dh.c:111 [inline]
 __keyctl_dh_compute+0x2b0/0x1990 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 20762:
 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:3485 [inline]
 kfree+0xd6/0x260 mm/slab.c:3800
 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]
 kfree_skb+0x15d/0x4c0 net/core/skbuff.c:659
 sctp_ulpevent_free+0x332/0x4a0 net/sctp/ulpevent.c:1132
 sctp_ulpq_tail_event+0x5d9/0xc40 net/sctp/ulpqueue.c:286
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1478 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1210 [inline]
 sctp_do_sm+0x12f3/0x6ed0 net/sctp/sm_sideeffect.c:1181
 sctp_assoc_bh_rcv+0x283/0x4b0 net/sctp/associola.c:1065
 sctp_inq_push+0x23b/0x300 net/sctp/inqueue.c:95
 sctp_backlog_rcv+0x177/0xa90 net/sctp/input.c:350
 sk_backlog_rcv include/net/sock.h:907 [inline]
 __release_sock+0x124/0x360 net/core/sock.c:2274
 release_sock+0xa4/0x2a0 net/core/sock.c:2789
 sctp_wait_for_connect+0x346/0x570 net/sctp/socket.c:8258
 __sctp_connect+0xa90/0xca0 net/sctp/socket.c:1274
 __sctp_setsockopt_connectx+0x1ae/0x1f0 net/sctp/socket.c:1387
 sctp_getsockopt_connectx3 net/sctp/socket.c:1472 [inline]
 sctp_getsockopt+0x4118/0x7328 net/sctp/socket.c:7157
 sock_common_getsockopt+0x95/0xd0 net/core/sock.c:2937
 SYSC_getsockopt net/socket.c:1852 [inline]
 SyS_getsockopt+0x178/0x340 net/socket.c:1834
 entry_SYSCALL_64_fastpath+0x1f/0x96

The buggy address belongs to the object at ffff8801cfbcd2c0
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 252 bytes inside of
 512-byte region [ffff8801cfbcd2c0, ffff8801cfbcd4c0)
The buggy address belongs to the page:
page:ffffea00073ef340 count:1 mapcount:0 mapping:ffff8801cfbcd040 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801cfbcd040 0000000000000000 0000000100000006
raw: ffffea00073ef420 ffffea00072f30e0 ffff8801dac00940 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801cfbcd300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801cfbcd380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801cfbcd400: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
                                              ^
 ffff8801cfbcd480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801cfbcd500: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
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