crypto: s5p-sss - Fix kernel Oops in AES-ECB mode

commit c927b080c67e3e97193c81fc1d27f4251bf4e036 upstream.

In AES-ECB mode crypt is done with key only, so any use of IV
can cause kernel Oops. Use IV only in AES-CBC and AES-CTR.

Signed-off-by: Kamil Konieczny <k.konieczny@partner.samsung.com>
Reported-by: Anand Moon <linux.amoon@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/crypto/s5p-sss.c b/drivers/crypto/s5p-sss.c
index cb86d4487605f6175cd3be29cec21b8f9711e18b..367a53f38cd69c947852e7c431196203a1b00efa 100644 (file)
--- a/drivers/crypto/s5p-sss.c
+++ b/drivers/crypto/s5p-sss.c
@@ -426,15 +426,21 @@ static void s5p_aes_crypt_start(struct s5p_aes_dev *dev, unsigned long mode)
        uint32_t                    aes_control;
        int                         err;
        unsigned long               flags;
+       u8 *iv;
 
        aes_control = SSS_AES_KEY_CHANGE_MODE;
        if (mode & FLAGS_AES_DECRYPT)
                aes_control |= SSS_AES_MODE_DECRYPT;
 
-       if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CBC)
+       if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CBC) {
                aes_control |= SSS_AES_CHAIN_MODE_CBC;
-       else if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CTR)
+               iv = req->info;
+       } else if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CTR) {
                aes_control |= SSS_AES_CHAIN_MODE_CTR;
+               iv = req->info;
+       } else {
+               iv = NULL; /* AES_ECB */
+       }
 
        if (dev->ctx->keylen == AES_KEYSIZE_192)
                aes_control |= SSS_AES_KEY_SIZE_192;
@@ -465,7 +471,7 @@ static void s5p_aes_crypt_start(struct s5p_aes_dev *dev, unsigned long mode)
                goto outdata_error;
 
        SSS_AES_WRITE(dev, AES_CONTROL, aes_control);
-       s5p_set_aes(dev, dev->ctx->aes_key, req->info, dev->ctx->keylen);
+       s5p_set_aes(dev, dev->ctx->aes_key, iv, dev->ctx->keylen);
 
        s5p_set_dma_indata(dev,  req->src);
        s5p_set_dma_outdata(dev, req->dst);