[FFmpeg-devel] [PATCH 03/17] avcodec/avcodec: Check for more invalid channel layouts

[Andreas Rheinhardt]

In particular, check the provided channel layout for encoders
without AVCodec.ch_layouts set. This fixes an infinite loop
in the WavPack encoder (and maybe other issues in other encoders
as well) in case the channel count is zero.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
---
 libavcodec/avcodec.c | 11 +++++++++++
 libavcodec/decode.c  |  5 -----
 libavcodec/encode.c  |  5 -----
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/libavcodec/avcodec.c b/libavcodec/avcodec.c
index a165cdea95..96b69e0a17 100644
--- a/libavcodec/avcodec.c
+++ b/libavcodec/avcodec.c
@@ -246,6 +246,17 @@ FF_DISABLE_DEPRECATION_WARNINGS
 FF_ENABLE_DEPRECATION_WARNINGS
 #endif
 
+    if (avctx->codec_type == AVMEDIA_TYPE_AUDIO && !avctx->ch_layout.nb_channels
+        && !(codec->capabilities & AV_CODEC_CAP_CHANNEL_CONF)) {
+        av_log(avctx, AV_LOG_ERROR, "Codec requires channel layout to be set\n");
+        ret = AVERROR(EINVAL);
+        goto free_and_end;
+    }
+    if (avctx->ch_layout.nb_channels && !av_channel_layout_check(&avctx->ch_layout)) {
+        av_log(avctx, AV_LOG_ERROR, "Invalid channel layout\n");
+        ret = AVERROR(EINVAL);
+        goto free_and_end;
+    }
     if (avctx->ch_layout.nb_channels > FF_SANE_NB_CHANNELS) {
         av_log(avctx, AV_LOG_ERROR, "Too many channels: %d\n", avctx->ch_layout.nb_channels);
         ret = AVERROR(EINVAL);
diff --git a/libavcodec/decode.c b/libavcodec/decode.c
index 2961705c9d..6be2d3d6ed 100644
--- a/libavcodec/decode.c
+++ b/libavcodec/decode.c
@@ -1595,11 +1595,6 @@ FF_DISABLE_DEPRECATION_WARNINGS
 FF_ENABLE_DEPRECATION_WARNINGS
 #endif
 
-    if (avctx->codec_type == AVMEDIA_TYPE_AUDIO && avctx->ch_layout.nb_channels == 0 &&
-        !(avctx->codec->capabilities & AV_CODEC_CAP_CHANNEL_CONF)) {
-        av_log(avctx, AV_LOG_ERROR, "Decoder requires channel count but channels not set\n");
-        return AVERROR(EINVAL);
-    }
     if (avctx->codec->max_lowres < avctx->lowres || avctx->lowres < 0) {
         av_log(avctx, AV_LOG_WARNING, "The maximum value for lowres supported by the decoder is %d\n",
                avctx->codec->max_lowres);
diff --git a/libavcodec/encode.c b/libavcodec/encode.c
index 2168b88ea8..92e8337227 100644
--- a/libavcodec/encode.c
+++ b/libavcodec/encode.c
@@ -600,11 +600,6 @@ static int encode_preinit_audio(AVCodecContext *avctx)
         return AVERROR(EINVAL);
     }
     if (avctx->codec->ch_layouts) {
-        if (!av_channel_layout_check(&avctx->ch_layout)) {
-            av_log(avctx, AV_LOG_WARNING, "Channel layout not specified correctly\n");
-            return AVERROR(EINVAL);
-        }
-
         for (i = 0; avctx->codec->ch_layouts[i].nb_channels; i++) {
             if (!av_channel_layout_compare(&avctx->ch_layout, &avctx->codec->ch_layouts[i]))
                 break;
-- 
2.34.1