Fix integer overflow in EmitFancyRGB.

+ enhance the assert in WebPCopyPlane()

Change-Id: Id9b01d00a8dce6caf0d4721a6fbe8def40b8bb85
This commit is contained in:
Vincent Rabaud 2020-05-05 14:31:49 +02:00
parent b3ff0bdec1
commit e3c259a278
2 changed files with 25 additions and 30 deletions

View File

@ -25,21 +25,16 @@
static int EmitYUV(const VP8Io* const io, WebPDecParams* const p) {
WebPDecBuffer* output = p->output;
const WebPYUVABuffer* const buf = &output->u.YUVA;
uint8_t* const y_dst = buf->y + io->mb_y * buf->y_stride;
uint8_t* const u_dst = buf->u + (io->mb_y >> 1) * buf->u_stride;
uint8_t* const v_dst = buf->v + (io->mb_y >> 1) * buf->v_stride;
uint8_t* const y_dst = buf->y + (size_t)io->mb_y * buf->y_stride;
uint8_t* const u_dst = buf->u + (size_t)(io->mb_y >> 1) * buf->u_stride;
uint8_t* const v_dst = buf->v + (size_t)(io->mb_y >> 1) * buf->v_stride;
const int mb_w = io->mb_w;
const int mb_h = io->mb_h;
const int uv_w = (mb_w + 1) / 2;
const int uv_h = (mb_h + 1) / 2;
int j;
for (j = 0; j < mb_h; ++j) {
memcpy(y_dst + j * buf->y_stride, io->y + j * io->y_stride, mb_w);
}
for (j = 0; j < uv_h; ++j) {
memcpy(u_dst + j * buf->u_stride, io->u + j * io->uv_stride, uv_w);
memcpy(v_dst + j * buf->v_stride, io->v + j * io->uv_stride, uv_w);
}
WebPCopyPlane(io->y, io->y_stride, y_dst, buf->y_stride, mb_w, mb_h);
WebPCopyPlane(io->u, io->uv_stride, u_dst, buf->u_stride, uv_w, uv_h);
WebPCopyPlane(io->v, io->uv_stride, v_dst, buf->v_stride, uv_w, uv_h);
return io->mb_h;
}
@ -47,7 +42,7 @@ static int EmitYUV(const VP8Io* const io, WebPDecParams* const p) {
static int EmitSampledRGB(const VP8Io* const io, WebPDecParams* const p) {
WebPDecBuffer* const output = p->output;
WebPRGBABuffer* const buf = &output->u.RGBA;
uint8_t* const dst = buf->rgba + io->mb_y * buf->stride;
uint8_t* const dst = buf->rgba + (size_t)io->mb_y * buf->stride;
WebPSamplerProcessPlane(io->y, io->y_stride,
io->u, io->v, io->uv_stride,
dst, buf->stride, io->mb_w, io->mb_h,
@ -62,7 +57,7 @@ static int EmitSampledRGB(const VP8Io* const io, WebPDecParams* const p) {
static int EmitFancyRGB(const VP8Io* const io, WebPDecParams* const p) {
int num_lines_out = io->mb_h; // a priori guess
const WebPRGBABuffer* const buf = &p->output->u.RGBA;
uint8_t* dst = buf->rgba + io->mb_y * buf->stride;
uint8_t* dst = buf->rgba + (size_t)io->mb_y * buf->stride;
WebPUpsampleLinePairFunc upsample = WebPUpsamplers[p->output->colorspace];
const uint8_t* cur_y = io->y;
const uint8_t* cur_u = io->u;
@ -133,7 +128,7 @@ static int EmitAlphaYUV(const VP8Io* const io, WebPDecParams* const p,
const WebPYUVABuffer* const buf = &p->output->u.YUVA;
const int mb_w = io->mb_w;
const int mb_h = io->mb_h;
uint8_t* dst = buf->a + io->mb_y * buf->a_stride;
uint8_t* dst = buf->a + (size_t)io->mb_y * buf->a_stride;
int j;
(void)expected_num_lines_out;
assert(expected_num_lines_out == mb_h);
@ -186,7 +181,7 @@ static int EmitAlphaRGB(const VP8Io* const io, WebPDecParams* const p,
(colorspace == MODE_ARGB || colorspace == MODE_Argb);
const WebPRGBABuffer* const buf = &p->output->u.RGBA;
int num_rows;
const int start_y = GetAlphaSourceRow(io, &alpha, &num_rows);
const size_t start_y = GetAlphaSourceRow(io, &alpha, &num_rows);
uint8_t* const base_rgba = buf->rgba + start_y * buf->stride;
uint8_t* const dst = base_rgba + (alpha_first ? 0 : 3);
const int has_alpha = WebPDispatchAlpha(alpha, io->width, mb_w,
@ -210,7 +205,7 @@ static int EmitAlphaRGBA4444(const VP8Io* const io, WebPDecParams* const p,
const WEBP_CSP_MODE colorspace = p->output->colorspace;
const WebPRGBABuffer* const buf = &p->output->u.RGBA;
int num_rows;
const int start_y = GetAlphaSourceRow(io, &alpha, &num_rows);
const size_t start_y = GetAlphaSourceRow(io, &alpha, &num_rows);
uint8_t* const base_rgba = buf->rgba + start_y * buf->stride;
#if (WEBP_SWAP_16BIT_CSP == 1)
uint8_t* alpha_dst = base_rgba;
@ -276,9 +271,9 @@ static int EmitRescaledYUV(const VP8Io* const io, WebPDecParams* const p) {
static int EmitRescaledAlphaYUV(const VP8Io* const io, WebPDecParams* const p,
int expected_num_lines_out) {
const WebPYUVABuffer* const buf = &p->output->u.YUVA;
uint8_t* const dst_a = buf->a + p->last_y * buf->a_stride;
uint8_t* const dst_a = buf->a + (size_t)p->last_y * buf->a_stride;
if (io->a != NULL) {
uint8_t* const dst_y = buf->y + p->last_y * buf->y_stride;
uint8_t* const dst_y = buf->y + (size_t)p->last_y * buf->y_stride;
const int num_lines_out = Rescale(io->a, io->width, io->mb_h, p->scaler_a);
assert(expected_num_lines_out == num_lines_out);
if (num_lines_out > 0) { // unmultiply the Y
@ -356,7 +351,7 @@ static int ExportRGB(WebPDecParams* const p, int y_pos) {
const WebPYUV444Converter convert =
WebPYUV444Converters[p->output->colorspace];
const WebPRGBABuffer* const buf = &p->output->u.RGBA;
uint8_t* dst = buf->rgba + y_pos * buf->stride;
uint8_t* dst = buf->rgba + (size_t)y_pos * buf->stride;
int num_lines_out = 0;
// For RGB rescaling, because of the YUV420, current scan position
// U/V can be +1/-1 line from the Y one. Hence the double test.
@ -383,15 +378,15 @@ static int EmitRescaledRGB(const VP8Io* const io, WebPDecParams* const p) {
while (j < mb_h) {
const int y_lines_in =
WebPRescalerImport(p->scaler_y, mb_h - j,
io->y + j * io->y_stride, io->y_stride);
io->y + (size_t)j * io->y_stride, io->y_stride);
j += y_lines_in;
if (WebPRescaleNeededLines(p->scaler_u, uv_mb_h - uv_j)) {
const int u_lines_in =
WebPRescalerImport(p->scaler_u, uv_mb_h - uv_j,
io->u + uv_j * io->uv_stride, io->uv_stride);
const int v_lines_in =
WebPRescalerImport(p->scaler_v, uv_mb_h - uv_j,
io->v + uv_j * io->uv_stride, io->uv_stride);
const int u_lines_in = WebPRescalerImport(
p->scaler_u, uv_mb_h - uv_j, io->u + (size_t)uv_j * io->uv_stride,
io->uv_stride);
const int v_lines_in = WebPRescalerImport(
p->scaler_v, uv_mb_h - uv_j, io->v + (size_t)uv_j * io->uv_stride,
io->uv_stride);
(void)v_lines_in; // remove a gcc warning
assert(u_lines_in == v_lines_in);
uv_j += u_lines_in;
@ -403,7 +398,7 @@ static int EmitRescaledRGB(const VP8Io* const io, WebPDecParams* const p) {
static int ExportAlpha(WebPDecParams* const p, int y_pos, int max_lines_out) {
const WebPRGBABuffer* const buf = &p->output->u.RGBA;
uint8_t* const base_rgba = buf->rgba + y_pos * buf->stride;
uint8_t* const base_rgba = buf->rgba + (size_t)y_pos * buf->stride;
const WEBP_CSP_MODE colorspace = p->output->colorspace;
const int alpha_first =
(colorspace == MODE_ARGB || colorspace == MODE_Argb);
@ -431,7 +426,7 @@ static int ExportAlpha(WebPDecParams* const p, int y_pos, int max_lines_out) {
static int ExportAlphaRGBA4444(WebPDecParams* const p, int y_pos,
int max_lines_out) {
const WebPRGBABuffer* const buf = &p->output->u.RGBA;
uint8_t* const base_rgba = buf->rgba + y_pos * buf->stride;
uint8_t* const base_rgba = buf->rgba + (size_t)y_pos * buf->stride;
#if (WEBP_SWAP_16BIT_CSP == 1)
uint8_t* alpha_dst = base_rgba;
#else
@ -470,7 +465,7 @@ static int EmitRescaledAlphaRGB(const VP8Io* const io, WebPDecParams* const p,
int lines_left = expected_num_out_lines;
const int y_end = p->last_y + lines_left;
while (lines_left > 0) {
const int row_offset = scaler->src_y - io->mb_y;
const size_t row_offset = scaler->src_y - io->mb_y;
WebPRescalerImport(scaler, io->mb_h + io->mb_y - scaler->src_y,
io->a + row_offset * io->width, io->width);
lines_left -= p->emit_alpha_row(p, y_end - lines_left, lines_left);

View File

@ -231,7 +231,7 @@ void WebPFree(void* ptr) {
void WebPCopyPlane(const uint8_t* src, int src_stride,
uint8_t* dst, int dst_stride, int width, int height) {
assert(src != NULL && dst != NULL);
assert(src_stride >= width && dst_stride >= width);
assert(abs(src_stride) >= width && abs(dst_stride) >= width);
while (height-- > 0) {
memcpy(dst, src, width);
src += src_stride;