[FFmpeg-devel] [PATCH] avcodec/htmlsubtitles: Be a bit more picky on syntax

[Michael Niedermayer]

This reduces the number of strstr() calls per byte

Fixes timeout
Fixes: 1817/clusterfuzz-testcase-minimized-5104230530547712

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/htmlsubtitles.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/htmlsubtitles.c b/libavcodec/htmlsubtitles.c
index 16295daa0c..e69681f31c 100644
--- a/libavcodec/htmlsubtitles.c
+++ b/libavcodec/htmlsubtitles.c
@@ -92,7 +92,7 @@ int ff_htmlmarkup_to_ass(void *log_ctx, AVBPrint *dst, const char *in)
         case '<':
             tag_close = in[1] == '/';
             len = 0;
-            if (sscanf(in+tag_close+1, "%127[^>]>%n", buffer, &len) >= 1 && len > 0) {
+            if (sscanf(in+tag_close+1, "%127[^<>]>%n", buffer, &len) >= 1 && len > 0) {
                 const char *tagname = buffer;
                 while (*tagname == ' ')
                     tagname++;
@@ -149,7 +149,7 @@ int ff_htmlmarkup_to_ass(void *log_ctx, AVBPrint *dst, const char *in)
                         }
                     } else if (tagname[0] && !tagname[1] && strspn(tagname, "bisu") == 1) {
                         av_bprintf(dst, "{\\%c%d}", tagname[0], !tag_close);
-                    } else {
+                    } else if (*tagname) {
                         unknown = 1;
                         snprintf(tmp, sizeof(tmp), "</%s>", tagname);
                     }
-- 
2.13.0