Fix some realloc error handling issues.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2625)

1 files changed, 6 insertions, 3 deletions

diff --git a/apps/engine.c b/apps/engine.c
index f54631b50d..a8eed9af5c 100644
--- a/apps/engine.c
+++ b/apps/engine.c
@@ -108,13 +108,16 @@ static int append_buf(char **buf, const char *s, int *size, int step)
     }
 
     if (strlen(*buf) + strlen(s) >= (unsigned int)*size) {
+        char *p = *buf;
+
         *size += step;
         *buf = OPENSSL_realloc(*buf, *size);
+        if (*buf == NULL) {
+            OPENSSL_free(p);
+            return 0;
+        }
     }
 
-    if (*buf == NULL)
-        return 0;
-
     if (**buf != '\0')
         BUF_strlcat(*buf, ", ", *size);
     BUF_strlcat(*buf, s, *size);