[PATCH 3.12 65/72] crypto: gcm - Fix IV buffer size in crypto_gcm_setkey

[Jiri Slaby]

From: Ondrej MosnÃÄek <omosnacek@xxxxxxxxx>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

commit 50d2e6dc1f83db0563c7d6603967bf9585ce934b upstream.

The cipher block size for GCM is 16 bytes, and thus the CTR transform
used in crypto_gcm_setkey() will also expect a 16-byte IV. However,
the code currently reserves only 8 bytes for the IV, causing
an out-of-bounds access in the CTR transform. This patch fixes
the issue by setting the size of the IV buffer to 16 bytes.

Fixes: 84c911523020 ("[CRYPTO] gcm: Add support for async ciphers")
Signed-off-by: Ondrej Mosnacek <omosnacek@xxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
 crypto/gcm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/gcm.c b/crypto/gcm.c
index d2a0f7371cf0..49b6fb20cceb 100644
--- a/crypto/gcm.c
+++ b/crypto/gcm.c
@@ -109,7 +109,7 @@ static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
 	struct crypto_ablkcipher *ctr = ctx->ctr;
 	struct {
 		be128 hash;
-		u8 iv[8];
+		u8 iv[16];
 
 		struct crypto_gcm_setkey_result result;
 
-- 
2.10.2