Description: fixing buffer read/write overruns in FLAC-code
 CVE-2017-8365, CVE-2017-8363, CVE-2017-8361
Author: Erik de Castro Lopo
Origin: upstream
Applied-Upstream: https://github.com/erikd/libsndfile/commit/fd0484aba8e51d16af1e3a880f9b8b857b385eb3
Last-Update: 2017-05-28
---
This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
--- libsndfile.orig/src/common.h
+++ libsndfile/src/common.h
@@ -725,6 +725,7 @@
 	SFE_FLAC_INIT_DECODER,
 	SFE_FLAC_LOST_SYNC,
 	SFE_FLAC_BAD_SAMPLE_RATE,
+	SFE_FLAC_CHANNEL_COUNT_CHANGED,
 	SFE_FLAC_UNKOWN_ERROR,
 
 	SFE_WVE_NOT_WVE,
--- libsndfile.orig/src/flac.c
+++ libsndfile/src/flac.c
@@ -435,6 +435,19 @@
 
 	switch (metadata->type)
 	{	case FLAC__METADATA_TYPE_STREAMINFO :
+			if (psf->sf.channels > 0 && psf->sf.channels != (int) metadata->data.stream_info.channels)
+			{	psf_log_printf (psf, "Error: FLAC stream changed from %d to %d channels\n"
+									"Nothing to be but to error out.\n" ,
+									psf->sf.channels, metadata->data.stream_info.channels) ;
+				psf->error = SFE_FLAC_CHANNEL_COUNT_CHANGED ;
+				return ;
+				} ;
+
+			if (psf->sf.channels > 0 && psf->sf.samplerate != (int) metadata->data.stream_info.sample_rate)
+			{	psf_log_printf (psf, "Warning: FLAC stream changed sample rates from %d to %d.\n"
+									"Carrying on as if nothing happened.",
+									psf->sf.samplerate, metadata->data.stream_info.sample_rate) ;
+				} ;
 			psf->sf.channels = metadata->data.stream_info.channels ;
 			psf->sf.samplerate = metadata->data.stream_info.sample_rate ;
 			psf->sf.frames = metadata->data.stream_info.total_samples ;
--- libsndfile.orig/src/sndfile.c
+++ libsndfile/src/sndfile.c
@@ -245,6 +245,7 @@
 	{	SFE_FLAC_INIT_DECODER	, "Error : problem with initialization of the flac decoder." },
 	{	SFE_FLAC_LOST_SYNC		, "Error : flac decoder lost sync." },
 	{	SFE_FLAC_BAD_SAMPLE_RATE, "Error : flac does not support this sample rate." },
+	{	SFE_FLAC_CHANNEL_COUNT_CHANGED, "Error : flac channel changed mid stream." },
 	{	SFE_FLAC_UNKOWN_ERROR	, "Error : unknown error in flac decoder." },
 
 	{	SFE_WVE_NOT_WVE			, "Error : not a WVE file." },
