crypto: qce - check return value of sg_nents_for_len

The sg_nents_for_len() function could fail, this patch add a check for
its return value.

Signed-off-by: LABBE Corentin <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

drivers/crypto/qce/ablkcipher.c

···
 		rctx->dst_nents = sg_nents_for_len(req->dst, req->nbytes);
 	else
 		rctx->dst_nents = rctx->src_nents;
+	if (rctx->src_nents < 0) {
+		dev_err(qce->dev, "Invalid numbers of src SG.\n");
+		return rctx->src_nents;
+	}
+	if (rctx->dst_nents < 0) {
+		dev_err(qce->dev, "Invalid numbers of dst SG.\n");
+		return -rctx->dst_nents;
+	}
 
 	rctx->dst_nents += 1;
 

drivers/crypto/qce/sha.c

···
 	}
 
 	rctx->src_nents = sg_nents_for_len(req->src, req->nbytes);
+	if (rctx->src_nents < 0) {
+		dev_err(qce->dev, "Invalid numbers of src SG.\n");
+		return rctx->src_nents;
+	}
+
 	ret = dma_map_sg(qce->dev, req->src, rctx->src_nents, DMA_TO_DEVICE);
 	if (ret < 0)
 		return ret;