check sscanf conversion, fixes Coverity 21666

ok doug@, miod@, guenther@

1 files changed, 6 insertions, 2 deletions

diff --git a/src/regress/lib/libcrypto/evp/evptest.c b/src/regress/lib/libcrypto/evp/evptest.c
index a71c1fb55a..bd5da475f1 100644
--- a/src/regress/lib/libcrypto/evp/evptest.c
+++ b/src/regress/lib/libcrypto/evp/evptest.c
@@ -81,10 +81,14 @@ convert(unsigned char *s)
                 unsigned int n;
 
                 if (!s[1]) {
-                        fprintf(stderr, "Odd number of hex digits!");
+                        fprintf(stderr, "Odd number of hex digits!\n");
                         exit(4);
                 }
-                sscanf((char *)s, "%2x",&n);
+                if (sscanf((char *)s, "%2x", &n) != 1) {
+                        fprintf(stderr, "Invalid hex value at %s\n", s);
+                        exit(4);
+                }
+
                 *d = (unsigned char)n;
         }
         return s - d;