improve sanity checks on gradient constructor parameters
BUG=445807
Review URL: https://codereview.chromium.org/837013002
diff --git a/src/effects/gradients/SkGradientShader.cpp b/src/effects/gradients/SkGradientShader.cpp
index d50afb7..d2b8bc3 100644
--- a/src/effects/gradients/SkGradientShader.cpp
+++ b/src/effects/gradients/SkGradientShader.cpp
@@ -735,6 +735,12 @@
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
+// Return true if these parameters are valid/legal/safe to construct a gradient
+//
+static bool valid_grad(const SkColor colors[], const SkScalar pos[], int count, unsigned tileMode) {
+ return NULL != colors && count >= 1 && tileMode < (unsigned)SkShader::kTileModeCount;
+}
+
// assumes colors is SkColor* and pos is SkScalar*
#define EXPAND_1_COLOR(count) \
SkColor tmp[2]; \
@@ -764,7 +770,10 @@
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
- if (NULL == pts || NULL == colors || colorCount < 1) {
+ if (!pts) {
+ return NULL;
+ }
+ if (!valid_grad(colors, pos, colorCount, mode)) {
return NULL;
}
EXPAND_1_COLOR(colorCount);
@@ -780,7 +789,10 @@
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
- if (radius <= 0 || NULL == colors || colorCount < 1) {
+ if (radius <= 0) {
+ return NULL;
+ }
+ if (!valid_grad(colors, pos, colorCount, mode)) {
return NULL;
}
EXPAND_1_COLOR(colorCount);
@@ -800,7 +812,10 @@
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
- if (startRadius < 0 || endRadius < 0 || NULL == colors || colorCount < 1) {
+ if (startRadius < 0 || endRadius < 0) {
+ return NULL;
+ }
+ if (!valid_grad(colors, pos, colorCount, mode)) {
return NULL;
}
EXPAND_1_COLOR(colorCount);
@@ -821,7 +836,10 @@
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
- if (startRadius < 0 || endRadius < 0 || NULL == colors || colorCount < 1) {
+ if (startRadius < 0 || endRadius < 0) {
+ return NULL;
+ }
+ if (!valid_grad(colors, pos, colorCount, mode)) {
return NULL;
}
if (start == end && startRadius == endRadius) {
@@ -865,7 +883,7 @@
int colorCount,
uint32_t flags,
const SkMatrix* localMatrix) {
- if (NULL == colors || colorCount < 1) {
+ if (!valid_grad(colors, pos, colorCount, SkShader::kClamp_TileMode)) {
return NULL;
}
EXPAND_1_COLOR(colorCount);