[FFmpeg-cvslog] avcodec/movtextenc: Fix infinite loop due to variable truncation

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Mon Nov 29 17:41:16 2021 +0100| [bb89a2f64fd1d74cc51af62d5ef133be274dd7af] | committer: Andreas Rheinhardt

avcodec/movtextenc: Fix infinite loop due to variable truncation

Regression since af043b839c38e850af1184fd6be691f8475c048e.
Fixes ticket #9409.

Reviewed-by: Philip Langdale <philipl at overt.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=bb89a2f64fd1d74cc51af62d5ef133be274dd7af
---

 libavcodec/movtextenc.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/libavcodec/movtextenc.c b/libavcodec/movtextenc.c
index 2ae5a9bf0b..0632463a63 100644
--- a/libavcodec/movtextenc.c
+++ b/libavcodec/movtextenc.c
@@ -84,7 +84,7 @@ typedef struct {
     uint8_t box_flags;
     StyleBox d;
     uint16_t text_pos;
-    uint16_t byte_count;
+    unsigned byte_count;
     char **fonts;
     int font_count;
     double font_scale_factor;
@@ -584,9 +584,9 @@ static void mov_text_cancel_overrides_cb(void *priv, const char *style_name)
     mov_text_ass_style_set(s, style);
 }
 
-static uint16_t utf8_strlen(const char *text, int len)
+static unsigned utf8_strlen(const char *text, int len)
 {
-    uint16_t i = 0, ret = 0;
+    unsigned i = 0, ret = 0;
     while (i < len) {
         char c = text[i];
         if ((c & 0x80) == 0)
@@ -606,7 +606,7 @@ static uint16_t utf8_strlen(const char *text, int len)
 
 static void mov_text_text_cb(void *priv, const char *text, int len)
 {
-    uint16_t utf8_len = utf8_strlen(text, len);
+    unsigned utf8_len = utf8_strlen(text, len);
     MovTextContext *s = priv;
     av_bprint_append_data(&s->buffer, text, len);
     // If it's not utf-8, just use the byte length