crypto: drbg - fix drbg_generate return val check
The drbg_generate returns 0 in success case. That means that
drbg_generate_long will always only generate drbg_max_request_bytes at
most. Longer requests will be truncated to drbg_max_request_bytes.
Reported-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/drbg.c b/crypto/drbg.c
index 8d2944f..5a218a5 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -1442,19 +1442,19 @@
unsigned char *buf, unsigned int buflen,
struct drbg_string *addtl)
{
- int len = 0;
+ unsigned int len = 0;
unsigned int slice = 0;
do {
- int tmplen = 0;
+ int err = 0;
unsigned int chunk = 0;
slice = ((buflen - len) / drbg_max_request_bytes(drbg));
chunk = slice ? drbg_max_request_bytes(drbg) : (buflen - len);
- tmplen = drbg_generate(drbg, buf + len, chunk, addtl);
- if (0 >= tmplen)
- return tmplen;
- len += tmplen;
+ err = drbg_generate(drbg, buf + len, chunk, addtl);
+ if (0 > err)
+ return err;
+ len += chunk;
} while (slice > 0 && (len < buflen));
- return len;
+ return 0;
}
/*