From e4d4a356744f29a3f9d650bb4e915435dc0d411a Mon Sep 17 00:00:00 2001
From: wheremyfoodat <44909372+wheremyfoodat@users.noreply.github.com>
Date: Tue, 23 Jul 2024 04:11:12 +0300
Subject: [PATCH] Renderer GL: Add UB checks

---
 include/PICA/gpu.hpp                 |  3 ++-
 src/core/renderer_gl/renderer_gl.cpp | 13 +++++++++++--
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/include/PICA/gpu.hpp b/include/PICA/gpu.hpp
index c4c8db5c1..ac2a49e6f 100644
--- a/include/PICA/gpu.hpp
+++ b/include/PICA/gpu.hpp
@@ -167,7 +167,8 @@ class GPU {
 			u32 index = paddr - PhysicalAddrs::VRAM;
 			return (T*)&vram[index];
 		} else [[unlikely]] {
-			Helpers::panic("[GPU] Tried to access unknown physical address: %08X", paddr);
+			Helpers::warn("[GPU] Tried to access unknown physical address: %08X", paddr);
+			return nullptr;
 		}
 	}
 
diff --git a/src/core/renderer_gl/renderer_gl.cpp b/src/core/renderer_gl/renderer_gl.cpp
index f26158aed..8b614d2db 100644
--- a/src/core/renderer_gl/renderer_gl.cpp
+++ b/src/core/renderer_gl/renderer_gl.cpp
@@ -659,7 +659,15 @@ OpenGL::Texture RendererGL::getTexture(Texture& tex) {
 	if (buffer.has_value()) {
 		return buffer.value().get().texture;
 	} else {
-		const auto textureData = std::span{gpu.getPointerPhys<u8>(tex.location), tex.sizeInBytes()};  // Get pointer to the texture data in 3DS memory
+		const u8* startPointer = gpu.getPointerPhys<u8>(tex.location);
+		const usize sizeInBytes = tex.sizeInBytes();
+
+		if (startPointer == nullptr || (sizeInBytes > 0 && gpu.getPointerPhys<u8>(tex.location + sizeInBytes - 1) == nullptr)) [[unlikely]] {
+			Helpers::warn("Out-of-bounds texture fetch");
+			return blankTexture;
+		}
+
+		const auto textureData = std::span{startPointer, tex.sizeInBytes()};  // Get pointer to the texture data in 3DS memory
 		Texture& newTex = textureCache.add(tex);
 		newTex.decodeTexture(textureData);
 
@@ -770,7 +778,8 @@ void RendererGL::textureCopy(u32 inputAddr, u32 outputAddr, u32 totalBytes, u32
 	if (inputWidth != 0) [[likely]] {
 		copyHeight = (copySize / inputWidth) * 8;
 	} else {
-		copyHeight = 0;
+		Helpers::warn("Zero-width texture copy");
+		return;
 	}
 
 	// Find the source surface.