codec.c: Defensively check the returned samples.

Earlier versions of the codec_opus samples_count callback can return
negative error values on undecodable frames.  This resulted in a divide by
zero exception.

* Added a defensive check in ast_codec_samples_count() for a "negative"
samples count return value.  Log the event and set the count to zero.

ASTERISK-27194

Change-Id: Icf69350307ecbbc80a3d74de46af9bd80ea17819

diff --git a/main/codec.c b/main/codec.c
index c253233bb634d256b8945fb039fbe699a92d546d..d0e63682b8ef2bcb6f0e870d5b05de45fd090e55 100644 (file)
--- a/main/codec.c
+++ b/main/codec.c
@@ -393,6 +393,11 @@ unsigned int ast_codec_samples_count(struct ast_frame *frame)
 
        if (codec->samples_count) {
                samples = codec->samples_count(frame);
+               if ((int) samples < 0) {
+                       ast_log(LOG_WARNING, "Codec %s returned invalid number of samples.\n",
+                               ast_format_get_name(frame->subclass.format));
+                       samples = 0;
+               }
        } else {
                ast_log(LOG_WARNING, "Unable to calculate samples for codec %s\n",
                        ast_format_get_name(frame->subclass.format));