From 8ab80707841a73ca7708e1e1aa97f3513fff3d35 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Tue, 18 Mar 2014 00:07:53 +0100
Subject: [PATCH] avcodec/utils: fix sizeof(AVFrame) dependence in 
 avcodec_encode_audio2()

This is a bit tricky, we allocate a correctly sized AVFrame but then only
copy the compile time AVFrame size, this is to ensure that user applications
which do not use the correct av frame API dont end with out of array reads.
Note, applications using the correct API have set extended_data and the
changed code will never be executed for them.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
---
 libavcodec/utils.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 11b874f764..cd04ca2aaf 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -1615,7 +1615,7 @@ int attribute_align_arg avcodec_encode_audio2(AVCodecContext *avctx,
                                               const AVFrame *frame,
                                               int *got_packet_ptr)
 {
-    AVFrame tmp;
+    AVFrame *extended_frame = NULL;
     AVFrame *padded_frame = NULL;
     int ret;
     AVPacket user_pkt = *avpkt;
@@ -1640,9 +1640,13 @@ int attribute_align_arg avcodec_encode_audio2(AVCodecContext *avctx,
         }
         av_log(avctx, AV_LOG_WARNING, "extended_data is not set.\n");
 
-        tmp = *frame;
-        tmp.extended_data = tmp.data;
-        frame = &tmp;
+        extended_frame = av_frame_alloc();
+        if (!extended_frame)
+            return AVERROR(ENOMEM);
+
+        memcpy(extended_frame, frame, sizeof(AVFrame));
+        extended_frame->extended_data = extended_frame->data;
+        frame = extended_frame;
     }
 
     /* check for valid frame size */
@@ -1650,14 +1654,15 @@ int attribute_align_arg avcodec_encode_audio2(AVCodecContext *avctx,
         if (avctx->codec->capabilities & CODEC_CAP_SMALL_LAST_FRAME) {
             if (frame->nb_samples > avctx->frame_size) {
                 av_log(avctx, AV_LOG_ERROR, "more samples than frame size (avcodec_encode_audio2)\n");
-                return AVERROR(EINVAL);
+                ret = AVERROR(EINVAL);
+                goto end;
             }
         } else if (!(avctx->codec->capabilities & CODEC_CAP_VARIABLE_FRAME_SIZE)) {
             if (frame->nb_samples < avctx->frame_size &&
                 !avctx->internal->last_audio_frame) {
                 ret = pad_last_frame(avctx, &padded_frame, frame);
                 if (ret < 0)
-                    return ret;
+                    goto end;
 
                 frame = padded_frame;
                 avctx->internal->last_audio_frame = 1;
@@ -1729,6 +1734,7 @@ int attribute_align_arg avcodec_encode_audio2(AVCodecContext *avctx,
 
 end:
     av_frame_free(&padded_frame);
+    av_free(extended_frame);
 
     return ret;
 }