avformat/dashdec: Fix memleak on allocation error, avoid allocation

get_content_url() allocates two buffers for temporary strings and when
one of them couldn't be allocated, it simply returns, although one of
the two allocations could have succeeded and would leak in this
scenario. This can be fixed by avoiding one of the temporary buffers.

Reviewed-by: Steven Liu <lq@chinaffmpeg.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

diff --git a/libavformat/dashdec.c b/libavformat/dashdec.c
index 23393d41f8ecd7ef1ad0ff23f24e3dda8280876a..548a71d6dc7ec430f083f2cc0c7b9d23573e45b6 100644 (file)
--- a/libavformat/dashdec.c
+++ b/libavformat/dashdec.c
@@ -472,11 +472,9 @@ static char *get_content_url(xmlNodePtr *baseurl_nodes,
     char *text;
     char *url = NULL;
     char *tmp_str = av_mallocz(max_url_size);
-    char *tmp_str_2 = av_mallocz(max_url_size);
 
-    if (!tmp_str || !tmp_str_2) {
+    if (!tmp_str)
         return NULL;
-    }
 
     for (i = 0; i < n_baseurl_nodes; ++i) {
         if (baseurl_nodes[i] &&
@@ -485,9 +483,7 @@ static char *get_content_url(xmlNodePtr *baseurl_nodes,
             text = xmlNodeGetContent(baseurl_nodes[i]->children);
             if (text) {
                 memset(tmp_str, 0, max_url_size);
-                memset(tmp_str_2, 0, max_url_size);
-                ff_make_absolute_url(tmp_str_2, max_url_size, tmp_str, text);
-                av_strlcpy(tmp_str, tmp_str_2, max_url_size);
+                ff_make_absolute_url(tmp_str, max_url_size, "", text);
                 xmlFree(text);
             }
         }
@@ -513,7 +509,6 @@ static char *get_content_url(xmlNodePtr *baseurl_nodes,
     }
 end:
     av_free(tmp_str);
-    av_free(tmp_str_2);
     return url;
 }