[PATCH 4.9 087/153] crypto: testmgr - Pad aes_ccm_enc_tv_template vector

Greg Kroah-Hartman
2017-03-10T09:21:57Z

From: Laura Abbott <labbott@redhat.com>

commit 1c68bb0f62bf8de8bb30123ea840d5168f25abea upstream.

Running with KASAN and crypto tests currently gives

BUG: KASAN: global-out-of-bounds in __test_aead+0x9d9/0x2200 at addr ffffffff8212fca0
Read of size 16 by task cryptomgr_test/1107
Address belongs to variable 0xffffffff8212fca0
CPU: 0 PID: 1107 Comm: cryptomgr_test Not tainted 4.10.0+ #45
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-1.fc24 04/01/2014
Call Trace:
dump_stack+0x63/0x8a
kasan_report.part.1+0x4a7/0x4e0
? __test_aead+0x9d9/0x2200
? crypto_ccm_init_crypt+0x218/0x3c0 [ccm]
kasan_report+0x20/0x30
check_memory_region+0x13c/0x1a0
memcpy+0x23/0x50
__test_aead+0x9d9/0x2200
? kasan_unpoison_shadow+0x35/0x50
? alg_test_akcipher+0xf0/0xf0
? crypto_skcipher_init_tfm+0x2e3/0x310
? crypto_spawn_tfm2+0x37/0x60
? crypto_ccm_init_tfm+0xa9/0xd0 [ccm]
? crypto_aead_init_tfm+0x7b/0x90
? crypto_alloc_tfm+0xc4/0x190
test_aead+0x28/0xc0
alg_test_aead+0x54/0xd0
alg_test+0x1eb/0x3d0
? alg_find_test+0x90/0x90
? __sched_text_start+0x8/0x8
? __wake_up_common+0x70/0xb0
cryptomgr_test+0x4d/0x60
kthread+0x173/0x1c0
? crypto_acomp_scomp_free_ctx+0x60/0x60
? kthread_create_on_node+0xa0/0xa0
ret_from_fork+0x2c/0x40
Memory state around the buggy address:
ffffffff8212fb80: 00 00 00 00 01 fa fa fa fa fa fa fa 00 00 00 00
ffffffff8212fc00: 00 01 fa fa fa fa fa fa 00 00 00 00 01 fa fa fa
>ffffffff8212fc80: fa fa fa fa 00 05 fa fa fa fa fa fa 00 00 00 00
^
ffffffff8212fd00: 01 fa fa fa fa fa fa fa 00 00 00 00 01 fa fa fa
ffffffff8212fd80: fa fa fa fa 00 00 00 00 00 05 fa fa fa fa fa fa

This always happens on the same IV which is less than 16 bytes.

Per Ard,

"CCM IVs are 16 bytes, but due to the way they are constructed
internally, the final couple of bytes of input IV are dont-cares.

Apparently, we do read all 16 bytes, which triggers the KASAN errors."

Fix this by padding the IV with null bytes to be at least 16 bytes.

Fixes: 0bc5a6c5c79a ("crypto: testmgr - Disable rfc4309 test and convert test vectors")
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
crypto/testmgr.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -22813,7 +22813,7 @@ static struct aead_testvec aes_ccm_enc_t
"\x09\x75\x9a\x9b\x3c\x9b\x27\x39",
.klen = 32,
.iv = "\x03\xf9\xd9\x4e\x63\xb5\x3d\x9d"
- "\x43\xf6\x1e\x50",
+ "\x43\xf6\x1e\x50\0\0\0\0",
.assoc = "\x57\xf5\x6b\x8b\x57\x5c\x3d\x3b"
"\x13\x02\x01\x0c\x83\x4c\x96\x35"
"\x8e\xd6\x39\xcf\x7d\x14\x9b\x94"