On Wed, Feb 12, 2025 at 06:23:01PM +0300, Dan Carpenter wrote:
> Hello Christian Marangi,
>
> Commit 9739f5f93b78 ("crypto: eip93 - Add Inside Secure SafeXcel
> EIP-93 crypto engine support") from Jan 14, 2025 (linux-next), leads
> to the following Smatch static checker warning:
>
> drivers/crypto/inside-secure/eip93/eip93-common.c:233 check_valid_request() warn: 'src_nents' unsigned <= 0
> drivers/crypto/inside-secure/eip93/eip93-common.c:237 check_valid_request() warn: error code type promoted to positive: 'src_nents'
> drivers/crypto/inside-secure/eip93/eip93-common.c:240 check_valid_request() warn: error code type promoted to positive: 'dst_nents'
>
> drivers/crypto/inside-secure/eip93/eip93-common.c
> 201 int check_valid_request(struct eip93_cipher_reqctx *rctx)
> 202 {
> 203 struct scatterlist *src = rctx->sg_src;
> 204 struct scatterlist *dst = rctx->sg_dst;
> 205 u32 src_nents, dst_nents;
> 206 u32 textsize = rctx->textsize;
> 207 u32 authsize = rctx->authsize;
> 208 u32 blksize = rctx->blksize;
> 209 u32 totlen_src = rctx->assoclen + rctx->textsize;
> 210 u32 totlen_dst = rctx->assoclen + rctx->textsize;
> 211 u32 copy_len;
> 212 bool src_align, dst_align;
> 213 int err = -EINVAL;
> 214
> 215 if (!IS_CTR(rctx->flags)) {
> 216 if (!IS_ALIGNED(textsize, blksize))
> 217 return err;
> 218 }
> 219
> 220 if (authsize) {
> 221 if (IS_ENCRYPT(rctx->flags))
> 222 totlen_dst += authsize;
> 223 else
> 224 totlen_src += authsize;
> 225 }
> 226
> 227 src_nents = sg_nents_for_len(src, totlen_src);
> 228 dst_nents = sg_nents_for_len(dst, totlen_dst);
>
> These return -EINVAL on error.
>
> 229
> 230 if (src == dst) {
> 231 src_nents = max(src_nents, dst_nents);
> 232 dst_nents = src_nents;
> --> 233 if (unlikely((totlen_src || totlen_dst) && src_nents <= 0))
> ^^^^^^^^^^^^^^
> It's unsigned so it can't be less than zero.
>
> 234 return err;
> 235
> 236 } else {
> 237 if (unlikely(totlen_src && src_nents <= 0))
> ^^^^^^^^^^^^^^
> 238 return err;
> 239
> 240 if (unlikely(totlen_dst && dst_nents <= 0))
> ^^^^^^^^^^^^^^
> Same.
>
> 241 return err;
> 242 }
> 243
> 244 if (authsize) {
> 245 if (dst_nents == 1 && src_nents == 1) {
> 246 src_align = eip93_is_sg_aligned(src, totlen_src, blksize);
>
Thanks, this wasn't reported in the first run so sorry for not noticing
this. I will take care of sending a follow-up patch to address this.
Again thanks for the report!
--
Ansuel
