[FFmpeg-cvslog] avfilter/f_metadata: use the return value of vsnprintf() to write the argument list

[James Almer]

ffmpeg | branch: master | James Almer <jamrial at gmail.com> | Sat Jul 19 00:36:51 2025 -0300| [b0159af6bc76553b1ab7546d821bb8c16a666cfd] | committer: James Almer

avfilter/f_metadata: use the return value of vsnprintf() to write the argument list

Should fix use-of-uninitialized-value under MSAN.

Signed-off-by: James Almer <jamrial at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b0159af6bc76553b1ab7546d821bb8c16a666cfd
---

 libavfilter/f_metadata.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavfilter/f_metadata.c b/libavfilter/f_metadata.c
index f4e4aa312d..a9036ab475 100644
--- a/libavfilter/f_metadata.c
+++ b/libavfilter/f_metadata.c
@@ -201,8 +201,8 @@ static void print_file(AVFilterContext *ctx, const char *msg, ...)
     va_start(argument_list, msg);
     if (msg) {
         char buf[128];
-        vsnprintf(buf, sizeof(buf), msg, argument_list);
-        avio_write(s->avio_context, buf, av_strnlen(buf, sizeof(buf)));
+        int ret = vsnprintf(buf, sizeof(buf), msg, argument_list);
+        avio_write(s->avio_context, buf, ret);
     }
     va_end(argument_list);
 }