BUG: KASAN: slab-out-of-bounds in cts_cbc_encrypt+0xec/0x3c0

BUG: KASAN: slab-out-of-bounds in cts_cbc_encrypt+0xec/0x3c0

[Qian Cai]

Just booting up the latest git master (b00d209) on an aarch64 server and saw
this.

[   42.448373] BUG: KASAN: slab-out-of-bounds in cts_cbc_encrypt+0xec/0x3c0
[   42.455157] Write of size 8 at addr ffff801dd06aaa40 by task
cryptomgr_test/409

[   42.464065] CPU: 3 PID: 409 Comm: cryptomgr_test Tainted: G        W       T
4.20.0-rc1+ #6
[   42.472517] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.50
06/01/2018
[   42.479826] Call trace:
[   42.482306]  dump_backtrace+0x0/0x248
[   42.486014]  show_stack+0x24/0x30
[   42.489372]  dump_stack+0xb8/0xf4
[   42.492730]  print_address_description+0x68/0x2b8
[   42.497492]  kasan_report+0x22c/0x340
[   42.501199]  __asan_store8+0x90/0xa0
[   42.504818]  cts_cbc_encrypt+0xec/0x3c0
[   42.508703]  simd_skcipher_encrypt+0xc4/0x198
[   42.513115]  __test_skcipher+0x6d4/0x1030
[   42.517173]  test_skcipher+0x48/0xf0
[   42.520793]  alg_test_skcipher+0x78/0x110
[   42.524852]  alg_test.part.6+0x238/0x4e8
[   42.528823]  alg_test+0x60/0xa8
[   42.532002]  cryptomgr_test+0x5c/0x68
[   42.535710]  kthread+0x18c/0x1d0
[   42.538977]  ret_from_fork+0x10/0x18

[   42.544102] Allocated by task 409:
[   42.547547]  kasan_kmalloc+0xd8/0x188
[   42.551254]  __kmalloc+0x1f8/0x470
[   42.554698]  __test_skcipher+0x18c/0x1030
[   42.558757]  test_skcipher+0x48/0xf0
[   42.562376]  alg_test_skcipher+0x78/0x110
[   42.566435]  alg_test.part.6+0x238/0x4e8
[   42.570406]  alg_test+0x60/0xa8
[   42.573586]  cryptomgr_test+0x5c/0x68
[   42.577293]  kthread+0x18c/0x1d0
[   42.580560]  ret_from_fork+0x10/0x18

[   42.585684] Freed by task 0:
[   42.588597] (stack is not available)

[   42.593722] The buggy address belongs to the object at ffff801dd06aa880
 which belongs to the cache kmalloc-512 of size 512
[   42.606397] The buggy address is located 448 bytes inside of
 512-byte region [ffff801dd06aa880, ffff801dd06aaa80)
[   42.618277] The buggy address belongs to the page:
[   42.623127] page:ffff7fe007741a80 count:1 mapcount:0 mapping:ffff801dc0010880
index:0xffff801dd06a5880
[   42.632548] flags: 0x1fffff0000000200(slab)
[   42.636785] raw: 1fffff0000000200 ffff801dc000fac0 ffff801dc000fac0
ffff801dc0010880
[   42.644625] raw: ffff801dd06a5880 000000000040002c 00000001ffffffff
0000000000000000
[   42.652461] page dumped because: kasan: bad access detected

[   42.659606] Memory state around the buggy address:
[   42.664455]  ffff801dd06aa900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00
[   42.671765]  ffff801dd06aa980: 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
fc
[   42.679075] >ffff801dd06aaa00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
fc
[   42.686383]                                            ^
[   42.691759]  ffff801dd06aaa80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
fc
[   42.699069]  ffff801dd06aab00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
fc
[   42.706377]
==================================================================

Any idea?