crypto: caam - check sg_count() return value

sg_count() internally calls sg_nents_for_len(), which could fail
in case the required number of bytes is larger than the total
bytes in the S/G.

Thus, add checks to validate the input.

Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/caam/caamalg.c b/drivers/crypto/caam/caamalg.c
index 05d4690..ed8a044 100644 (file)
--- a/drivers/crypto/caam/caamalg.c
+++ b/drivers/crypto/caam/caamalg.c
@@ -1335,13 +1335,31 @@ static struct aead_edesc *aead_edesc_alloc(struct aead_request *req,
 
        if (unlikely(req->dst != req->src)) {
                src_nents = sg_count(req->src, req->assoclen + req->cryptlen);
+               if (unlikely(src_nents < 0)) {
+                       dev_err(jrdev, "Insufficient bytes (%d) in src S/G\n",
+                               req->assoclen + req->cryptlen);
+                       return ERR_PTR(src_nents);
+               }
+
                dst_nents = sg_count(req->dst,
                                     req->assoclen + req->cryptlen +
                                        (encrypt ? authsize : (-authsize)));
+               if (unlikely(dst_nents < 0)) {
+                       dev_err(jrdev, "Insufficient bytes (%d) in dst S/G\n",
+                               req->assoclen + req->cryptlen +
+                               (encrypt ? authsize : (-authsize)));
+                       return ERR_PTR(dst_nents);
+               }
        } else {
                src_nents = sg_count(req->src,
                                     req->assoclen + req->cryptlen +
                                        (encrypt ? authsize : 0));
+               if (unlikely(src_nents < 0)) {
+                       dev_err(jrdev, "Insufficient bytes (%d) in src S/G\n",
+                               req->assoclen + req->cryptlen +
+                               (encrypt ? authsize : 0));
+                       return ERR_PTR(src_nents);
+               }
        }
 
        /* Check if data are contiguous. */
@@ -1609,9 +1627,20 @@ static struct ablkcipher_edesc *ablkcipher_edesc_alloc(struct ablkcipher_request
        int sec4_sg_index;
 
        src_nents = sg_count(req->src, req->nbytes);
+       if (unlikely(src_nents < 0)) {
+               dev_err(jrdev, "Insufficient bytes (%d) in src S/G\n",
+                       req->nbytes);
+               return ERR_PTR(src_nents);
+       }
 
-       if (req->dst != req->src)
+       if (req->dst != req->src) {
                dst_nents = sg_count(req->dst, req->nbytes);
+               if (unlikely(dst_nents < 0)) {
+                       dev_err(jrdev, "Insufficient bytes (%d) in dst S/G\n",
+                               req->nbytes);
+                       return ERR_PTR(dst_nents);
+               }
+       }
 
        if (likely(req->src == req->dst)) {
                sgc = dma_map_sg(jrdev, req->src, src_nents ? : 1,
@@ -1807,6 +1836,11 @@ static struct ablkcipher_edesc *ablkcipher_giv_edesc_alloc(
        int sec4_sg_index;
 
        src_nents = sg_count(req->src, req->nbytes);
+       if (unlikely(src_nents < 0)) {
+               dev_err(jrdev, "Insufficient bytes (%d) in src S/G\n",
+                       req->nbytes);
+               return ERR_PTR(src_nents);
+       }
 
        if (likely(req->src == req->dst)) {
                sgc = dma_map_sg(jrdev, req->src, src_nents ? : 1,
@@ -1826,6 +1860,12 @@ static struct ablkcipher_edesc *ablkcipher_giv_edesc_alloc(
                }
 
                dst_nents = sg_count(req->dst, req->nbytes);
+               if (unlikely(dst_nents < 0)) {
+                       dev_err(jrdev, "Insufficient bytes (%d) in dst S/G\n",
+                               req->nbytes);
+                       return ERR_PTR(dst_nents);
+               }
+
                sgc = dma_map_sg(jrdev, req->dst, dst_nents ? : 1,
                                 DMA_FROM_DEVICE);
                if (unlikely(!sgc)) {
@@ -1914,7 +1954,7 @@ static int ablkcipher_givencrypt(struct skcipher_givcrypt_request *creq)
        struct crypto_ablkcipher *ablkcipher = crypto_ablkcipher_reqtfm(req);
        struct caam_ctx *ctx = crypto_ablkcipher_ctx(ablkcipher);
        struct device *jrdev = ctx->jrdev;
-       bool iv_contig;
+       bool iv_contig = false;
        u32 *desc;
        int ret = 0;