subparse: Check for NULL return of strchr() when parsing LRC subtitles

Thanks to Antonio Morales for finding and reporting the issue.

Fixes GHSL-2024-263
Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/3892

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/8051>

diff --git a/subprojects/gst-plugins-base/gst/subparse/gstsubparse.c b/subprojects/gst-plugins-base/gst/subparse/gstsubparse.c
index 994cf62d1acc50f60a7564cb39a22441d1032413..4fe43d91003f661387712f565beda124d9689308 100644 (file)
--- a/subprojects/gst-plugins-base/gst/subparse/gstsubparse.c
+++ b/subprojects/gst-plugins-base/gst/subparse/gstsubparse.c
@@ -1066,6 +1066,11 @@ parse_lrc (ParserState * state, const gchar * line)
     return NULL;
 
   start = strchr (line, ']');
+  // sscanf() does not check for the trailing ] but only up to the last
+  // placeholder, so there might be no ] at the end.
+  if (!start)
+    return NULL;
+
   if (start - line == 9)
     milli = 10;
   else