PPGe/savedata: Add a bunch of safety checks for png images. Fixes Digimon save crash, see #20125.

Core/Dialog/SavedataParam.cpp

@@ -1720,11 +1720,13 @@ void SavedataParam::ClearFileInfo(SaveFileInfo &saveInfo, const std::string &sav
 	}
 
 	if (GetPspParam()->newData.IsValid() && GetPspParam()->newData->buf.IsValid()) {
-		// We have a png to show
+		// We may have a png to show
 		if (!noSaveIcon) {
 			noSaveIcon = new SaveFileInfo();
 			PspUtilitySavedataFileData *newData = GetPspParam()->newData;
-			noSaveIcon->texture = new PPGeImage(newData->buf.ptr, (SceSize)newData->size);
+			if (Memory::IsValidRange(newData->buf.ptr, newData->size)) {
+				noSaveIcon->texture = new PPGeImage(newData->buf.ptr, (SceSize)newData->size);
+			}
 		}
 		saveInfo.texture = noSaveIcon->texture;
 	} else if ((u32)GetPspParam()->mode == SCE_UTILITY_SAVEDATA_TYPE_SAVE && GetPspParam()->icon0FileData.buf.IsValid()) {

Core/Util/PPGeDraw.cpp

@@ -1343,12 +1343,17 @@ void PPGeDisableTexture()
 
 std::vector<PPGeImage *> PPGeImage::loadedTextures_;
 
+constexpr size_t MAX_VALID_IMAGE_SIZE = 16 * 1024 * 1024;
+
 PPGeImage::PPGeImage(std::string_view pspFilename)
 	: filename_(pspFilename) {
 }
 
 PPGeImage::PPGeImage(u32 pngPointer, size_t pngSize)
 	: filename_(""), png_(pngPointer), size_(pngSize) {
+	if (!Memory::IsValidRange(this->png_, this->size_)) {
+		WARN_LOG(Log::sceGe, "Created PPGeImage from invalid memory range %08x (%08x bytes). Will not be drawn.");
+	}
 }
 
 PPGeImage::~PPGeImage() {
@@ -1366,7 +1371,13 @@ bool PPGeImage::Load() {
 	unsigned char *textureData;
 	int success;
 	if (filename_.empty()) {
-		success = pngLoadPtr(Memory::GetPointerRange(png_, (u32)size_), size_, &width_, &height_, &textureData);
+		_dbg_assert_(size_ < MAX_VALID_IMAGE_SIZE);
+		const u8 *srcPtr = Memory::GetPointerRange(png_, (u32)size_);
+		if (!srcPtr) {
+			ERROR_LOG(Log::sceGe, "Trying to load PPGeImage from invalid range: %08x, %08x bytes", png_, size_);
+			return false;
+		}
+		success = pngLoadPtr(srcPtr, size_, &width_, &height_, &textureData);
 	} else {
 		std::vector<u8> pngData;
 		if (pspFileSystem.ReadEntireFile(filename_, pngData) < 0) {
@@ -1406,6 +1417,10 @@ bool PPGeImage::IsValid() {
 	if (loadFailed_)
 		return false;
 
+	if (!Memory::IsValidRange(this->png_, this->size_)) {
+		return false;
+	}
+
 	if (texture_ == 0) {
 		Decimate();
 		return Load();

Core/Util/PPGeDraw.h

@@ -146,14 +146,14 @@ private:
 	std::string filename_;
 
 	// Only valid if filename_.empty().
-	u32 png_;
-	size_t size_;
+	u32 png_ = 0;
+	size_t size_ = 0;
 
 	u32 texture_ = 0;
-	int width_;
-	int height_;
+	int width_ = 0;
+	int height_ = 0;
 
-	int lastFrame_;
+	int lastFrame_ = 0;
 	bool loadFailed_ = false;
 };