[FFmpeg-cvslog] fftools/ffmpeg: Avoid allocating+freeing frame, check allocations

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Fri Dec  3 20:30:33 2021 +0100| [b886512ef2503fc585c302484be71475d3100480] | committer: Andreas Rheinhardt

fftools/ffmpeg: Avoid allocating+freeing frame, check allocations

Fixes a potential crash upon av_frame_alloc() failure.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b886512ef2503fc585c302484be71475d3100480
---

 fftools/ffmpeg.c     | 11 ++++-------
 fftools/ffmpeg_opt.c |  4 ++++
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
index 47e6a8683e..b0b32a69f2 100644
--- a/fftools/ffmpeg.c
+++ b/fftools/ffmpeg.c
@@ -1291,7 +1291,7 @@ static void do_video_out(OutputFile *of,
         int forced_keyframe = 0;
         double pts_time;
 
-        if (i < nb0_frames && ost->last_frame) {
+        if (i < nb0_frames && ost->last_frame->buf[0]) {
             in_picture = ost->last_frame;
         } else
             in_picture = next_picture;
@@ -1419,13 +1419,10 @@ static void do_video_out(OutputFile *of,
             do_video_stats(ost, frame_size);
     }
 
-    if (!ost->last_frame)
-        ost->last_frame = av_frame_alloc();
     av_frame_unref(ost->last_frame);
-    if (next_picture && ost->last_frame)
-        av_frame_ref(ost->last_frame, next_picture);
-    else
-        av_frame_free(&ost->last_frame);
+    if (next_picture)
+        if (av_frame_ref(ost->last_frame, next_picture) < 0)
+            goto error;
 
     return;
 error:
diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c
index eea57a6974..a703798586 100644
--- a/fftools/ffmpeg_opt.c
+++ b/fftools/ffmpeg_opt.c
@@ -1905,6 +1905,10 @@ static OutputStream *new_video_stream(OptionsContext *o, AVFormatContext *oc, in
         ost->avfilter = get_ost_filters(o, oc, ost);
         if (!ost->avfilter)
             exit_program(1);
+
+        ost->last_frame = av_frame_alloc();
+        if (!ost->last_frame)
+            exit_program(1);
     } else {
         MATCH_PER_STREAM_OPT(copy_initial_nonkeyframes, i, ost->copy_initial_nonkeyframes, oc ,st);
     }