avcodec/tdsc: Fix tile checks

Fixes: out of array access
Fixes: crash.asf

Found-by: anton listov <greyfarn7@yandex.ru>
Reviewed-by: anton listov <greyfarn7@yandex.ru>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2020-07-15 22:47:50 +02:00
parent 8544783280
commit 081e3001ed

View File

@ -390,7 +390,7 @@ static int tdsc_decode_tiles(AVCodecContext *avctx, int number_tiles)
for (i = 0; i < number_tiles; i++) {
int tile_size;
int tile_mode;
int x, y, w, h;
int x, y, x2, y2, w, h;
int ret;
if (bytestream2_get_bytes_left(&ctx->gbc) < 4 ||
@ -408,20 +408,19 @@ static int tdsc_decode_tiles(AVCodecContext *avctx, int number_tiles)
bytestream2_skip(&ctx->gbc, 4); // unknown
x = bytestream2_get_le32(&ctx->gbc);
y = bytestream2_get_le32(&ctx->gbc);
w = bytestream2_get_le32(&ctx->gbc) - x;
h = bytestream2_get_le32(&ctx->gbc) - y;
x2 = bytestream2_get_le32(&ctx->gbc);
y2 = bytestream2_get_le32(&ctx->gbc);
if (x >= ctx->width || y >= ctx->height) {
if (x < 0 || y < 0 || x2 <= x || y2 <= y ||
x2 > ctx->width || y2 > ctx->height
) {
av_log(avctx, AV_LOG_ERROR,
"Invalid tile position (%d.%d outside %dx%d).\n",
x, y, ctx->width, ctx->height);
return AVERROR_INVALIDDATA;
}
if (x + w > ctx->width || y + h > ctx->height) {
av_log(avctx, AV_LOG_ERROR,
"Invalid tile size %dx%d\n", w, h);
"Invalid tile position (%d.%d %d.%d outside %dx%d).\n",
x, y, x2, y2, ctx->width, ctx->height);
return AVERROR_INVALIDDATA;
}
w = x2 - x;
h = y2 - y;
ret = av_reallocp(&ctx->tilebuffer, tile_size);
if (!ctx->tilebuffer)