lavf: block special characters in dump metadata

This is limited to the chars that arent filtered by av_log() already
we might filter more aggressively if theres some case where this becomes
needed.

Fixes Ticket1181

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/utils.c

@@ -3812,7 +3812,7 @@ static void dump_metadata(void *ctx, AVDictionary *m, const char *indent)
                 av_log(ctx, AV_LOG_INFO, "%s  %-16s: ", indent, tag->key);
                 while(*p) {
                     char tmp[256];
-                    size_t len = strcspn(p, "\xd\xa");
+                    size_t len = strcspn(p, "\x8\xa\xb\xc\xd");
                     av_strlcpy(tmp, p, FFMIN(sizeof(tmp), len+1));
                     av_log(ctx, AV_LOG_INFO, "%s", tmp);
                     p += len;