crypto: mxc-scc - signedness bugs in mxc_scc_ablkcipher_req_init()

->src_nents and ->dst_nents are unsigned so they can't be less than
zero.  I fixed this by introducing a temporary "nents" variable.

Fixes: d293b640ebd5 ('crypto: mxc-scc - add basic driver for the MXC SCC')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/mxc-scc.c b/drivers/crypto/mxc-scc.c
index 38b01bf141d38b4a3db121189a85a964a79ea326..9b348a78dd23df6c9772053d7902bc8e371e1bba 100644 (file)
--- a/drivers/crypto/mxc-scc.c
+++ b/drivers/crypto/mxc-scc.c
@@ -210,18 +210,21 @@ static int mxc_scc_ablkcipher_req_init(struct ablkcipher_request *req,
                                       struct mxc_scc_ctx *ctx)
 {
        struct mxc_scc *scc = ctx->scc;
+       int nents;
 
-       ctx->src_nents = sg_nents_for_len(req->src, req->nbytes);
-       if (ctx->src_nents < 0) {
+       nents = sg_nents_for_len(req->src, req->nbytes);
+       if (nents < 0) {
                dev_err(scc->dev, "Invalid number of src SC");
-               return ctx->src_nents;
+               return nents;
        }
+       ctx->src_nents = nents;
 
-       ctx->dst_nents = sg_nents_for_len(req->dst, req->nbytes);
-       if (ctx->dst_nents < 0) {
+       nents = sg_nents_for_len(req->dst, req->nbytes);
+       if (nents < 0) {
                dev_err(scc->dev, "Invalid number of dst SC");
-               return ctx->dst_nents;
+               return nents;
        }
+       ctx->dst_nents = nents;
 
        ctx->size = 0;
        ctx->offset = 0;