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-rw-r--r--libavcodec/dxa.c100
1 files changed, 67 insertions, 33 deletions
diff --git a/libavcodec/dxa.c b/libavcodec/dxa.c
index 989fcb965b..c8e3f71399 100644
--- a/libavcodec/dxa.c
+++ b/libavcodec/dxa.c
@@ -2,20 +2,20 @@
* Feeble Files/ScummVM DXA decoder
* Copyright (c) 2007 Konstantin Shishkov
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
@@ -29,6 +29,7 @@
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
+#include "bytestream.h"
#include "avcodec.h"
#include "internal.h"
@@ -41,6 +42,7 @@ typedef struct DxaDecContext {
AVFrame *prev;
int dsize;
+#define DECOMP_BUF_PADDING 16
uint8_t *decomp_buf;
uint32_t pal[256];
} DxaDecContext;
@@ -49,13 +51,17 @@ static const int shift1[6] = { 0, 8, 8, 8, 4, 4 };
static const int shift2[6] = { 0, 0, 8, 4, 0, 4 };
static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst,
- int stride, uint8_t *src, uint8_t *ref)
+ int stride, uint8_t *src, int srcsize, uint8_t *ref)
{
uint8_t *code, *data, *mv, *msk, *tmp, *tmp2;
+ uint8_t *src_end = src + srcsize;
int i, j, k;
int type, x, y, d, d2;
uint32_t mask;
+ if (12ULL + ((avctx->width * avctx->height) >> 4) + AV_RB32(src + 0) + AV_RB32(src + 4) > srcsize)
+ return AVERROR_INVALIDDATA;
+
code = src + 12;
data = code + ((avctx->width * avctx->height) >> 4);
mv = data + AV_RB32(src + 0);
@@ -63,6 +69,8 @@ static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst,
for(j = 0; j < avctx->height; j += 4){
for(i = 0; i < avctx->width; i += 4){
+ if (data > src_end || mv > src_end || msk > src_end)
+ return AVERROR_INVALIDDATA;
tmp = dst + i;
tmp2 = ref + i;
type = *code++;
@@ -70,6 +78,11 @@ static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst,
case 4: // motion compensation
x = (*mv) >> 4; if(x & 8) x = 8 - x;
y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
+ if (i < -x || avctx->width - i - 4 < x ||
+ j < -y || avctx->height - j - 4 < y) {
+ av_log(avctx, AV_LOG_ERROR, "MV %d %d out of bounds\n", x,y);
+ return AVERROR_INVALIDDATA;
+ }
tmp2 += x + y*stride;
case 0: // skip
case 5: // skip in method 12
@@ -127,6 +140,11 @@ static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst,
case 0x80: // motion compensation
x = (*mv) >> 4; if(x & 8) x = 8 - x;
y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
+ if (i + 2*(k & 1) < -x || avctx->width - i - 2*(k & 1) - 2 < x ||
+ j + (k & 2) < -y || avctx->height - j - (k & 2) - 2 < y) {
+ av_log(avctx, AV_LOG_ERROR, "MV %d %d out of bounds\n", x,y);
+ return AVERROR_INVALIDDATA;
+ }
tmp2 += x + y*stride;
case 0x00: // skip
tmp[d + 0 ] = tmp2[0];
@@ -192,35 +210,27 @@ static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst,
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
{
AVFrame *frame = data;
- const uint8_t *buf = avpkt->data;
- int buf_size = avpkt->size;
DxaDecContext * const c = avctx->priv_data;
uint8_t *outptr, *srcptr, *tmpptr;
unsigned long dsize;
int i, j, compr, ret;
int stride;
- int orig_buf_size = buf_size;
int pc = 0;
+ GetByteContext gb;
- /* make the palette available on the way out */
- if(buf[0]=='C' && buf[1]=='M' && buf[2]=='A' && buf[3]=='P'){
- int r, g, b;
+ bytestream2_init(&gb, avpkt->data, avpkt->size);
- buf += 4;
+ /* make the palette available on the way out */
+ if (bytestream2_peek_le32(&gb) == MKTAG('C','M','A','P')) {
+ bytestream2_skip(&gb, 4);
for(i = 0; i < 256; i++){
- r = *buf++;
- g = *buf++;
- b = *buf++;
- c->pal[i] = (r << 16) | (g << 8) | b;
+ c->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&gb);
}
pc = 1;
- buf_size -= 768+4;
}
- if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) {
- av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
return ret;
- }
memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
frame->palette_has_changed = pc;
@@ -229,16 +239,25 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
tmpptr = c->prev->data[0];
stride = frame->linesize[0];
- if(buf[0]=='N' && buf[1]=='U' && buf[2]=='L' && buf[3]=='L')
+ if (bytestream2_get_le32(&gb) == MKTAG('N','U','L','L'))
compr = -1;
else
- compr = buf[4];
+ compr = bytestream2_get_byte(&gb);
dsize = c->dsize;
- if((compr != 4 && compr != -1) && uncompress(c->decomp_buf, &dsize, buf + 9, buf_size - 9) != Z_OK){
- av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n");
- return AVERROR_UNKNOWN;
+ if (compr != 4 && compr != -1) {
+ bytestream2_skip(&gb, 4);
+ if (uncompress(c->decomp_buf, &dsize, avpkt->data + bytestream2_tell(&gb),
+ bytestream2_get_bytes_left(&gb)) != Z_OK) {
+ av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n");
+ return AVERROR_UNKNOWN;
+ }
+ memset(c->decomp_buf + dsize, 0, DECOMP_BUF_PADDING);
}
+
+ if (avctx->debug & FF_DEBUG_PICT_INFO)
+ av_log(avctx, AV_LOG_DEBUG, "compr:%2d, dsize:%d\n", compr, (int)dsize);
+
switch(compr){
case -1:
frame->key_frame = 0;
@@ -265,14 +284,18 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
case 5:
if (!tmpptr) {
av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
- return AVERROR_INVALIDDATA;
+ if (!(avctx->flags2 & CODEC_FLAG2_SHOW_ALL))
+ return AVERROR_INVALIDDATA;
}
frame->key_frame = 0;
frame->pict_type = AV_PICTURE_TYPE_P;
for (j = 0; j < avctx->height; j++) {
- for (i = 0; i < avctx->width; i++)
- outptr[i] = srcptr[i] ^ tmpptr[i];
- tmpptr += stride;
+ if(tmpptr){
+ for(i = 0; i < avctx->width; i++)
+ outptr[i] = srcptr[i] ^ tmpptr[i];
+ tmpptr += stride;
+ }else
+ memcpy(outptr, srcptr, avctx->width);
outptr += stride;
srcptr += avctx->width;
}
@@ -281,10 +304,14 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
case 13:
frame->key_frame = 0;
frame->pict_type = AV_PICTURE_TYPE_P;
- decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, c->prev->data[0]);
+ if (!c->prev->data[0]) {
+ av_log(avctx, AV_LOG_ERROR, "Missing reference frame\n");
+ return AVERROR_INVALIDDATA;
+ }
+ decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, dsize, c->prev->data[0]);
break;
default:
- av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", buf[4]);
+ av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", compr);
return AVERROR_INVALIDDATA;
}
@@ -295,13 +322,18 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
*got_frame = 1;
/* always report that the buffer was completely consumed */
- return orig_buf_size;
+ return avpkt->size;
}
static av_cold int decode_init(AVCodecContext *avctx)
{
DxaDecContext * const c = avctx->priv_data;
+ if (avctx->width%4 || avctx->height%4) {
+ avpriv_request_sample(avctx, "dimensions are not a multiple of 4");
+ return AVERROR_INVALIDDATA;
+ }
+
c->prev = av_frame_alloc();
if (!c->prev)
return AVERROR(ENOMEM);
@@ -309,7 +341,9 @@ static av_cold int decode_init(AVCodecContext *avctx)
avctx->pix_fmt = AV_PIX_FMT_PAL8;
c->dsize = avctx->width * avctx->height * 2;
- if (!(c->decomp_buf = av_malloc(c->dsize))) {
+ c->decomp_buf = av_malloc(c->dsize + DECOMP_BUF_PADDING);
+ if (!c->decomp_buf) {
+ av_frame_free(&c->prev);
av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
return AVERROR(ENOMEM);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-09 22:57:46 +0000