[PATCH 3.16 240/410] crypto: s5p-sss - Fix kernel Oops in AES-ECB mode

From: Ben Hutchings
Date: Thu Jun 07 2018 - 10:24:04 EST


3.16.57-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Kamil Konieczny <k.konieczny@xxxxxxxxxxxxxxxxxxx>

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@xxxxxxxxxxxxxxxxxxx>
Reported-by: Anand Moon <linux.amoon@xxxxxxxxx>
Reviewed-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
Tested-by: Anand Moon <linux.amoon@xxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/crypto/s5p-sss.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

--- a/drivers/crypto/s5p-sss.c
+++ b/drivers/crypto/s5p-sss.c
@@ -426,15 +426,21 @@ static void s5p_aes_crypt_start(struct s
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 s
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);