Merge commit '7ebdffc353f3f0827864e8e3461fdc00cc243b14'

* commit '7ebdffc353f3f0827864e8e3461fdc00cc243b14':
  dxv: Check to make sure we don't overrun buffers on corrupt inputs

Merged-by: Clément Bœsch <u@pkh.me>
This commit is contained in:
Clément Bœsch 2017-03-15 23:26:10 +01:00
commit d96f6df3a6
1 changed files with 10 additions and 6 deletions

View File

@ -133,7 +133,7 @@ static int dxv_decompress_dxt1(AVCodecContext *avctx)
AV_WL32(ctx->tex_data + 4, bytestream2_get_le32(gbc));
/* Process input until the whole texture has been filled */
while (pos < ctx->tex_size / 4) {
while (pos + 2 <= ctx->tex_size / 4) {
CHECKPOINT(2);
/* Copy two elements from a previous offset or from the input buffer */
@ -186,7 +186,7 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx)
AV_WL32(ctx->tex_data + 12, bytestream2_get_le32(gbc));
/* Process input until the whole texture has been filled */
while (pos < ctx->tex_size / 4) {
while (pos + 2 <= ctx->tex_size / 4) {
if (run) {
run--;
@ -215,7 +215,7 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx)
check += probe;
} while (probe == 0xFFFF);
}
while (check && pos < ctx->tex_size / 4) {
while (check && pos + 4 <= ctx->tex_size / 4) {
prev = AV_RL32(ctx->tex_data + 4 * (pos - 4));
AV_WL32(ctx->tex_data + 4 * pos, prev);
pos++;
@ -260,10 +260,8 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx)
case 2:
/* Copy two dwords from a previous index */
idx = 8 + bytestream2_get_le16(gbc);
if (idx > pos) {
av_log(avctx, AV_LOG_ERROR, "idx %d > %d\n", idx, pos);
if (idx > pos || (unsigned int)(pos - idx) + 2 > ctx->tex_size / 4)
return AVERROR_INVALIDDATA;
}
prev = AV_RL32(ctx->tex_data + 4 * (pos - idx));
AV_WL32(ctx->tex_data + 4 * pos, prev);
pos++;
@ -286,9 +284,13 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx)
}
CHECKPOINT(4);
if (pos + 2 > ctx->tex_size / 4)
return AVERROR_INVALIDDATA;
/* Copy two elements from a previous offset or from the input buffer */
if (op) {
if (idx > pos || (unsigned int)(pos - idx) + 2 > ctx->tex_size / 4)
return AVERROR_INVALIDDATA;
prev = AV_RL32(ctx->tex_data + 4 * (pos - idx));
AV_WL32(ctx->tex_data + 4 * pos, prev);
pos++;
@ -299,6 +301,8 @@ static int dxv_decompress_dxt5(AVCodecContext *avctx)
} else {
CHECKPOINT(4);
if (op && (idx > pos || (unsigned int)(pos - idx) + 2 > ctx->tex_size / 4))
return AVERROR_INVALIDDATA;
if (op)
prev = AV_RL32(ctx->tex_data + 4 * (pos - idx));
else