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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 194 at addr ffff8801ca2dd1bc by task syz-executor4/11077

CPU: 1 PID: 11077 Comm: syz-executor4 Not tainted 4.15.0-rc4-next-20171221+ #78
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+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:00007f35913e6c58 EFLAGS: 00000212 ORIG_RAX: 00000000000000fa
RAX: ffffffffffffffda RBX: 00007f35913e7700 RCX: 0000000000452ac9
RDX: 0000000020cff000 RSI: 0000000020d0bff4 RDI: 0000000000000017
RBP: 0000000000000000 R08: 0000000020523fc8 R09: 0000000000000000
R10: 000000000000002a R11: 0000000000000212 R12: 0000000000000000
R13: 0000000000a2f7ef R14: 00007f35913e79c0 R15: 0000000000000000

Allocated by task 11077:
 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:3709 [inline]
 __kmalloc+0x162/0x760 mm/slab.c:3718
 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 8461:
 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:3489 [inline]
 kfree+0xd6/0x260 mm/slab.c:3804
 load_elf_binary+0x24b9/0x4c10 fs/binfmt_elf.c:1110
 search_binary_handler+0x142/0x6b0 fs/exec.c:1634
 exec_binprm fs/exec.c:1676 [inline]
 do_execveat_common.isra.30+0x1711/0x22a0 fs/exec.c:1798
 do_execve+0x31/0x40 fs/exec.c:1843
 call_usermodehelper_exec_async+0x457/0x8f0 kernel/umh.c:100
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:524

The buggy address belongs to the object at ffff8801ca2dd0c0
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 252 bytes inside of
 512-byte region [ffff8801ca2dd0c0, ffff8801ca2dd2c0)
The buggy address belongs to the page:
page:0000000004cce666 count:1 mapcount:0 mapping:000000002718fc14 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801ca2dd0c0 0000000000000000 0000000100000006
raw: ffffea0007393c20 ffffea00072bf7a0 ffff8801dac00940 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801ca2dd100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801ca2dd180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801ca2dd200: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
                                              ^
 ffff8801ca2dd280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801ca2dd300: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
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