Fix heap-buffer-overflow in color_sycc_to_rgb

It's a bug existing in the conversion from YUV420 to RGB.
For YUV 420 format, four pixels have 4 Y but only one U and
one V. In some cases, there are odd columns or lines in
some images. The pixels on last line or column may have Y
but no U or V data. For this case, We shall extend U or V
using the data on previous column or line.

BUG=497357
R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1342683002 .

3 files changed, 160 insertions, 40 deletions

diff --git a/core/src/fxcodec/codec/codec_int.h b/core/src/fxcodec/codec/codec_int.h
index b08dee7422..9f408dd9a2 100644
--- a/core/src/fxcodec/codec/codec_int.h
+++ b/core/src/fxcodec/codec/codec_int.h
@@ -312,6 +312,8 @@ struct DecodeData {
   OPJ_SIZE_T offset;
 };
 
+void sycc420_to_rgb(opj_image_t* img);
+
 /* Wrappers for C-style callbacks. */
 OPJ_SIZE_T opj_read_from_memory(void* p_buffer,
                                 OPJ_SIZE_T nb_bytes,
diff --git a/core/src/fxcodec/codec/fx_codec_jpx_opj.cpp b/core/src/fxcodec/codec/fx_codec_jpx_opj.cpp
index 76d62f763b..616af36b00 100644
--- a/core/src/fxcodec/codec/fx_codec_jpx_opj.cpp
+++ b/core/src/fxcodec/codec/fx_codec_jpx_opj.cpp
@@ -11,6 +11,7 @@
 #include "../../../../third_party/lcms2-2.6/include/lcms2.h"
 #include "../../../../third_party/libopenjpeg20/openjpeg.h"
 #include "../../../include/fxcodec/fx_codec.h"
+#include "../../../include/fxcrt/fx_safe_types.h"
 #include "codec_int.h"
 
 static void fx_error_callback(const char* msg, void* client_data) {
@@ -256,29 +257,58 @@ static void sycc422_to_rgb(opj_image_t* img) {
   img->comps[1].dy = img->comps[0].dy;
   img->comps[2].dy = img->comps[0].dy;
 }
-static void sycc420_to_rgb(opj_image_t* img) {
-  int *d0, *d1, *d2, *r, *g, *b, *nr, *ng, *nb;
-  const int *y, *cb, *cr, *ny;
-  int maxw, maxh, max, offset, upb;
-  int i, j;
-  i = (int)img->comps[0].prec;
-  offset = 1 << (i - 1);
-  upb = (1 << i) - 1;
-  maxw = (int)img->comps[0].w;
-  maxh = (int)img->comps[0].h;
-  max = maxw * maxh;
-  y = img->comps[0].data;
-  cb = img->comps[1].data;
-  cr = img->comps[2].data;
-  d0 = r = FX_Alloc(int, (size_t)max);
-  d1 = g = FX_Alloc(int, (size_t)max);
-  d2 = b = FX_Alloc(int, (size_t)max);
-  for (i = 0; (OPJ_UINT32)i < (maxh & ~(OPJ_UINT32)1); i += 2) {
-    ny = y + maxw;
-    nr = r + maxw;
-    ng = g + maxw;
-    nb = b + maxw;
-    for (j = 0; (OPJ_UINT32)j < (maxw & ~(OPJ_UINT32)1); j += 2) {
+static bool sycc420_size_is_valid(OPJ_UINT32 y, OPJ_UINT32 cbcr) {
+  if (!y || !cbcr)
+    return false;
+
+  return (cbcr == y / 2) || ((y & 1) && (cbcr == y / 2 + 1));
+}
+static bool sycc420_must_extend_cbcr(OPJ_UINT32 y, OPJ_UINT32 cbcr) {
+  return (y & 1) && (cbcr == y / 2);
+}
+void sycc420_to_rgb(opj_image_t* img) {
+  OPJ_UINT32 prec = img->comps[0].prec;
+  if (!prec)
+    return;
+  OPJ_UINT32 offset = 1 << (prec - 1);
+  OPJ_UINT32 upb = (1 << prec) - 1;
+  OPJ_UINT32 yw = img->comps[0].w;
+  OPJ_UINT32 yh = img->comps[0].h;
+  OPJ_UINT32 cbw = img->comps[1].w;
+  OPJ_UINT32 cbh = img->comps[1].h;
+  OPJ_UINT32 crw = img->comps[2].w;
+  OPJ_UINT32 crh = img->comps[2].h;
+  if (cbw != crw || cbh != crh)
+    return;
+  if (!sycc420_size_is_valid(yw, cbw) || !sycc420_size_is_valid(yh, cbh))
+    return;
+  bool extw = sycc420_must_extend_cbcr(yw, cbw);
+  bool exth = sycc420_must_extend_cbcr(yh, cbh);
+  FX_SAFE_DWORD safeSize = yw;
+  safeSize *= yh;
+  if (!safeSize.IsValid())
+    return;
+  int* r = FX_Alloc(int, safeSize.ValueOrDie());
+  int* g = FX_Alloc(int, safeSize.ValueOrDie());
+  int* b = FX_Alloc(int, safeSize.ValueOrDie());
+  int* d0 = r;
+  int* d1 = g;
+  int* d2 = b;
+  const int* y = img->comps[0].data;
+  const int* cb = img->comps[1].data;
+  const int* cr = img->comps[2].data;
+  const int* ny = nullptr;
+  int* nr = nullptr;
+  int* ng = nullptr;
+  int* nb = nullptr;
+  OPJ_UINT32 i = 0;
+  OPJ_UINT32 j = 0;
+  for (i = 0; i < (yh & ~(OPJ_UINT32)1); i += 2) {
+    ny = y + yw;
+    nr = r + yw;
+    ng = g + yw;
+    nb = b + yw;
+    for (j = 0; j < (yw & ~(OPJ_UINT32)1); j += 2) {
       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
       ++y;
       ++r;
@@ -302,7 +332,11 @@ static void sycc420_to_rgb(opj_image_t* img) {
       ++cb;
       ++cr;
     }
-    if (j < maxw) {
+    if (j < yw) {
+      if (extw) {
+        --cb;
+        --cr;
+      }
       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
       ++y;
       ++r;
@@ -316,13 +350,17 @@ static void sycc420_to_rgb(opj_image_t* img) {
       ++cb;
       ++cr;
     }
-    y += maxw;
-    r += maxw;
-    g += maxw;
-    b += maxw;
-  }
-  if (i < maxh) {
-    for (j = 0; (OPJ_UINT32)j < (maxw & ~(OPJ_UINT32)1); j += 2) {
+    y += yw;
+    r += yw;
+    g += yw;
+    b += yw;
+  }
+  if (i < yh) {
+    if (exth) {
+      cb -= cbw;
+      cr -= crw;
+    }
+    for (j = 0; j < (yw & ~(OPJ_UINT32)1); j += 2) {
       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
       ++y;
       ++r;
@@ -336,7 +374,11 @@ static void sycc420_to_rgb(opj_image_t* img) {
       ++cb;
       ++cr;
     }
-    if (j < maxw) {
+    if (j < yw) {
+      if (extw) {
+        --cb;
+        --cr;
+      }
       sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
     }
   }
@@ -347,14 +389,14 @@ static void sycc420_to_rgb(opj_image_t* img) {
   img->comps[1].data = d1;
   FX_Free(img->comps[2].data);
   img->comps[2].data = d2;
-  img->comps[1].w = maxw;
-  img->comps[1].h = maxh;
-  img->comps[2].w = maxw;
-  img->comps[2].h = maxh;
-  img->comps[1].w = (OPJ_UINT32)maxw;
-  img->comps[1].h = (OPJ_UINT32)maxh;
-  img->comps[2].w = (OPJ_UINT32)maxw;
-  img->comps[2].h = (OPJ_UINT32)maxh;
+  img->comps[1].w = yw;
+  img->comps[1].h = yh;
+  img->comps[2].w = yw;
+  img->comps[2].h = yh;
+  img->comps[1].w = yw;
+  img->comps[1].h = yh;
+  img->comps[2].w = yw;
+  img->comps[2].h = yh;
   img->comps[1].dx = img->comps[0].dx;
   img->comps[2].dx = img->comps[0].dx;
   img->comps[1].dy = img->comps[0].dy;
diff --git a/core/src/fxcodec/codec/fx_codec_jpx_unittest.cpp b/core/src/fxcodec/codec/fx_codec_jpx_unittest.cpp
index 3add606509..2dabb5379d 100644
--- a/core/src/fxcodec/codec/fx_codec_jpx_unittest.cpp
+++ b/core/src/fxcodec/codec/fx_codec_jpx_unittest.cpp
@@ -464,3 +464,79 @@ TEST(fxcodec, DecodeDataSeek) {
   EXPECT_EQ(kReadError, opj_read_from_memory(buffer, 1, &dd));
   EXPECT_EQ(0xbd, buffer[0]);
 }
+
+TEST(fxcodec, YUV420ToRGB) {
+  opj_image_comp_t u;
+  memset(&u, 0, sizeof(u));
+  u.dx = 1;
+  u.dy = 1;
+  u.w = 16;
+  u.h = 16;
+  u.prec = 8;
+  u.bpp = 8;
+  u.data = FX_Alloc(OPJ_INT32, u.w * u.h);
+  memset(u.data, 0, u.w * u.h * sizeof(OPJ_INT32));
+  opj_image_comp_t v;
+  memset(&v, 0, sizeof(v));
+  v.dx = 1;
+  v.dy = 1;
+  v.w = 16;
+  v.h = 16;
+  v.prec = 8;
+  v.bpp = 8;
+  v.data = FX_Alloc(OPJ_INT32, v.w * v.h);
+  memset(v.data, 0, v.w * v.h * sizeof(OPJ_INT32));
+  opj_image_comp_t y;
+  memset(&y, 0, sizeof(y));
+  y.dx = 1;
+  y.dy = 1;
+  y.prec = 8;
+  y.bpp = 8;
+  opj_image_t img;
+  memset(&img, 0, sizeof(img));
+  img.numcomps = 3;
+  img.color_space = OPJ_CLRSPC_SYCC;
+  img.comps = FX_Alloc(opj_image_comp_t, 3);
+  const struct {
+    int w;
+    bool expected;
+  } cases[] = {{0, false},
+               {1, false},
+               {30, false},
+               {31, true},
+               {32, true},
+               {33, true},
+               {34, false},
+               {UINT_MAX, false}};
+  for (int i = 0; i < sizeof(cases) / sizeof(cases[0]); ++i) {
+    y.w = cases[i].w;
+    y.h = y.w;
+    img.x1 = y.w;
+    img.y1 = y.h;
+    y.data = FX_Alloc(OPJ_INT32, y.w * y.h);
+    memset(y.data, 1, y.w * y.h * sizeof(OPJ_INT32));
+    u.data = FX_Alloc(OPJ_INT32, u.w * u.h);
+    memset(u.data, 0, u.w * u.h * sizeof(OPJ_INT32));
+    v.data = FX_Alloc(OPJ_INT32, v.w * v.h);
+    memset(v.data, 0, v.w * v.h * sizeof(OPJ_INT32));
+    img.comps[0] = y;
+    img.comps[1] = u;
+    img.comps[2] = v;
+    sycc420_to_rgb(&img);
+    if (cases[i].expected) {
+      EXPECT_EQ(img.comps[0].w, img.comps[1].w);
+      EXPECT_EQ(img.comps[0].h, img.comps[1].h);
+      EXPECT_EQ(img.comps[0].w, img.comps[2].w);
+      EXPECT_EQ(img.comps[0].h, img.comps[2].h);
+    } else {
+      EXPECT_NE(img.comps[0].w, img.comps[1].w);
+      EXPECT_NE(img.comps[0].h, img.comps[1].h);
+      EXPECT_NE(img.comps[0].w, img.comps[2].w);
+      EXPECT_NE(img.comps[0].h, img.comps[2].h);
+    }
+    FX_Free(img.comps[0].data);
+    FX_Free(img.comps[1].data);
+    FX_Free(img.comps[2].data);
+  }
+  FX_Free(img.comps);
+}