ffmdec: validate codec parameters

A negative extradata size for example gets passed to memcpy in
avcodec_parameters_from_context causing a segmentation fault.

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
This commit is contained in:
Andreas Cadhalpun 2016-11-17 00:04:57 +01:00
parent ac206bb175
commit 1c7da19a4b

View File

@ -21,6 +21,7 @@
#include <stdint.h>
#include "libavutil/imgutils.h"
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/intfloat.h"
@ -28,6 +29,7 @@
#include "libavutil/avassert.h"
#include "libavutil/avstring.h"
#include "libavutil/pixdesc.h"
#include "libavcodec/internal.h"
#include "avformat.h"
#include "internal.h"
#include "ffm.h"
@ -277,6 +279,14 @@ static int ffm_append_recommended_configuration(AVStream *st, char **conf)
return 0;
}
#define VALIDATE_PARAMETER(parameter, name, check) { \
if (check) { \
av_log(codec, AV_LOG_ERROR, "Invalid " name " %d\n", codec->parameter); \
ret = AVERROR_INVALIDDATA; \
goto fail; \
} \
}
static int ffm2_read_header(AVFormatContext *s)
{
FFMContext *ffm = s->priv_data;
@ -342,6 +352,7 @@ static int ffm2_read_header(AVFormatContext *s)
if (!codec_desc) {
av_log(s, AV_LOG_ERROR, "Invalid codec id: %d\n", codec->codec_id);
codec->codec_id = AV_CODEC_ID_NONE;
ret = AVERROR_INVALIDDATA;
goto fail;
}
codec->codec_type = avio_r8(pb);
@ -350,14 +361,25 @@ static int ffm2_read_header(AVFormatContext *s)
codec_desc->type, codec->codec_type);
codec->codec_id = AV_CODEC_ID_NONE;
codec->codec_type = AVMEDIA_TYPE_UNKNOWN;
ret = AVERROR_INVALIDDATA;
goto fail;
}
codec->bit_rate = avio_rb32(pb);
if (codec->bit_rate < 0) {
av_log(codec, AV_LOG_ERROR, "Invalid bit rate %"PRId64"\n", codec->bit_rate);
ret = AVERROR_INVALIDDATA;
goto fail;
}
codec->flags = avio_rb32(pb);
codec->flags2 = avio_rb32(pb);
codec->debug = avio_rb32(pb);
if (codec->flags & AV_CODEC_FLAG_GLOBAL_HEADER) {
int size = avio_rb32(pb);
if (size < 0 || size >= FF_MAX_EXTRADATA_SIZE) {
av_log(s, AV_LOG_ERROR, "Invalid extradata size %d\n", size);
ret = AVERROR_INVALIDDATA;
goto fail;
}
codec->extradata = av_mallocz(size + AV_INPUT_BUFFER_PADDING_SIZE);
if (!codec->extradata)
return AVERROR(ENOMEM);
@ -380,6 +402,9 @@ static int ffm2_read_header(AVFormatContext *s)
}
codec->width = avio_rb16(pb);
codec->height = avio_rb16(pb);
ret = av_image_check_size(codec->width, codec->height, 0, s);
if (ret < 0)
goto fail;
codec->gop_size = avio_rb16(pb);
codec->pix_fmt = avio_rb32(pb);
if (!av_pix_fmt_desc_get(codec->pix_fmt)) {
@ -432,13 +457,11 @@ static int ffm2_read_header(AVFormatContext *s)
goto fail;
}
codec->sample_rate = avio_rb32(pb);
if (codec->sample_rate <= 0) {
av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", codec->sample_rate);
ret = AVERROR_INVALIDDATA;
goto fail;
}
VALIDATE_PARAMETER(sample_rate, "sample rate", codec->sample_rate < 0)
codec->channels = avio_rl16(pb);
VALIDATE_PARAMETER(channels, "number of channels", codec->channels < 0)
codec->frame_size = avio_rl16(pb);
VALIDATE_PARAMETER(frame_size, "frame size", codec->frame_size < 0)
break;
case MKBETAG('C', 'P', 'R', 'V'):
if (f_cprv++) {
@ -518,7 +541,7 @@ static int ffm_read_header(AVFormatContext *s)
AVIOContext *pb = s->pb;
AVCodecContext *codec;
const AVCodecDescriptor *codec_desc;
int i, nb_streams;
int i, nb_streams, ret;
uint32_t tag;
/* header */
@ -570,6 +593,10 @@ static int ffm_read_header(AVFormatContext *s)
goto fail;
}
codec->bit_rate = avio_rb32(pb);
if (codec->bit_rate < 0) {
av_log(codec, AV_LOG_WARNING, "Invalid bit rate %"PRId64"\n", codec->bit_rate);
goto fail;
}
codec->flags = avio_rb32(pb);
codec->flags2 = avio_rb32(pb);
codec->debug = avio_rb32(pb);
@ -585,6 +612,8 @@ static int ffm_read_header(AVFormatContext *s)
}
codec->width = avio_rb16(pb);
codec->height = avio_rb16(pb);
if (av_image_check_size(codec->width, codec->height, 0, s) < 0)
goto fail;
codec->gop_size = avio_rb16(pb);
codec->pix_fmt = avio_rb32(pb);
if (!av_pix_fmt_desc_get(codec->pix_fmt)) {
@ -633,18 +662,21 @@ static int ffm_read_header(AVFormatContext *s)
break;
case AVMEDIA_TYPE_AUDIO:
codec->sample_rate = avio_rb32(pb);
if (codec->sample_rate <= 0) {
av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", codec->sample_rate);
goto fail;
}
VALIDATE_PARAMETER(sample_rate, "sample rate", codec->sample_rate < 0)
codec->channels = avio_rl16(pb);
VALIDATE_PARAMETER(channels, "number of channels", codec->channels < 0)
codec->frame_size = avio_rl16(pb);
VALIDATE_PARAMETER(frame_size, "frame size", codec->frame_size < 0)
break;
default:
goto fail;
}
if (codec->flags & AV_CODEC_FLAG_GLOBAL_HEADER) {
int size = avio_rb32(pb);
if (size < 0 || size >= FF_MAX_EXTRADATA_SIZE) {
av_log(s, AV_LOG_ERROR, "Invalid extradata size %d\n", size);
goto fail;
}
codec->extradata = av_mallocz(size + AV_INPUT_BUFFER_PADDING_SIZE);
if (!codec->extradata)
return AVERROR(ENOMEM);