From ab64ae8c6386655cd2c1e27f026f56f60ab51f8e Mon Sep 17 00:00:00 2001
From: Joshua Wise <joshua@accelerated.tech>
Date: Sun, 22 Jan 2023 00:58:19 -0500
Subject: [PATCH] slic3r: address sanitizer cleanup in ImGuiWrapper::load_svg

ImGuiWrapper::load_svg previously could load an image that was not of the
aspect ratio specified by the target_width and target_height, and as a
result, could create an output vector that was smaller (or differently
shaped!) than the target_width and target_height.  GCC's Address Sanitizer
flagged this because init_font was reading over the end of the allocated
buffer, but this also meant that images with incorrect aspect ratios might
get rendered to the font canvas incorrectly.

To solve this, we pass the generated width and height out from load_svg, and
use it when copying images later.
---
 src/slic3r/GUI/ImGuiWrapper.cpp | 26 ++++++++++++++++----------
 src/slic3r/GUI/ImGuiWrapper.hpp |  2 +-
 2 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/src/slic3r/GUI/ImGuiWrapper.cpp b/src/slic3r/GUI/ImGuiWrapper.cpp
index fe4d57fce..1582fe35a 100644
--- a/src/slic3r/GUI/ImGuiWrapper.cpp
+++ b/src/slic3r/GUI/ImGuiWrapper.cpp
@@ -1636,7 +1636,7 @@ static const ImWchar ranges_keyboard_shortcuts[] =
 #endif // __APPLE__
 
 
-std::vector<unsigned char> ImGuiWrapper::load_svg(const std::string& bitmap_name, unsigned target_width, unsigned target_height)
+std::vector<unsigned char> ImGuiWrapper::load_svg(const std::string& bitmap_name, unsigned target_width, unsigned target_height, unsigned *outwidth, unsigned *outheight)
 {
     std::vector<unsigned char> empty_vector;
 
@@ -1667,6 +1667,9 @@ std::vector<unsigned char> ImGuiWrapper::load_svg(const std::string& bitmap_name
     ::nsvgDeleteRasterizer(rast);
     ::nsvgDelete(image);
 
+    *outwidth = width;
+    *outheight = height;
+
     return data;
 }
 
@@ -1951,11 +1954,12 @@ void ImGuiWrapper::init_font(bool compress)
         if (const ImFontAtlas::CustomRect* rect = io.Fonts->GetCustomRectByIndex(rect_id)) {
             assert(rect->Width == icon_sz);
             assert(rect->Height == icon_sz);
-            std::vector<unsigned char> raw_data = load_svg(icon.second, icon_sz, icon_sz);
+            unsigned outwidth, outheight;
+            std::vector<unsigned char> raw_data = load_svg(icon.second, icon_sz, icon_sz, &outwidth, &outheight);
             const ImU32* pIn = (ImU32*)raw_data.data();
-            for (int y = 0; y < icon_sz; y++) {
+            for (unsigned y = 0; y < outheight; y++) {
                 ImU32* pOut = (ImU32*)pixels + (rect->Y + y) * width + (rect->X);
-                for (int x = 0; x < icon_sz; x++)
+                for (unsigned x = 0; x < outwidth; x++)
                     *pOut++ = *pIn++;
             }
         }
@@ -1967,11 +1971,12 @@ void ImGuiWrapper::init_font(bool compress)
         if (const ImFontAtlas::CustomRect* rect = io.Fonts->GetCustomRectByIndex(rect_id)) {
             assert(rect->Width == icon_sz);
             assert(rect->Height == icon_sz);
-            std::vector<unsigned char> raw_data = load_svg(icon.second, icon_sz, icon_sz);
+            unsigned outwidth, outheight;
+            std::vector<unsigned char> raw_data = load_svg(icon.second, icon_sz, icon_sz, &outwidth, &outheight);
             const ImU32* pIn = (ImU32*)raw_data.data();
-            for (int y = 0; y < icon_sz; y++) {
+            for (unsigned y = 0; y < outheight; y++) {
                 ImU32* pOut = (ImU32*)pixels + (rect->Y + y) * width + (rect->X);
-                for (int x = 0; x < icon_sz; x++)
+                for (unsigned x = 0; x < outwidth; x++)
                     *pOut++ = *pIn++;
             }
         }
@@ -1983,11 +1988,12 @@ void ImGuiWrapper::init_font(bool compress)
         if (const ImFontAtlas::CustomRect* rect = io.Fonts->GetCustomRectByIndex(rect_id)) {
             assert(rect->Width == icon_sz);
             assert(rect->Height == icon_sz);
-            std::vector<unsigned char> raw_data = load_svg(icon.second, icon_sz, icon_sz);
+            unsigned outwidth, outheight;
+            std::vector<unsigned char> raw_data = load_svg(icon.second, icon_sz, icon_sz, &outwidth, &outheight);
             const ImU32* pIn = (ImU32*)raw_data.data();
-            for (int y = 0; y < icon_sz; y++) {
+            for (unsigned y = 0; y < outheight; y++) {
                 ImU32* pOut = (ImU32*)pixels + (rect->Y + y) * width + (rect->X);
-                for (int x = 0; x < icon_sz; x++)
+                for (unsigned x = 0; x < outwidth; x++)
                     *pOut++ = *pIn++;
             }
         }
diff --git a/src/slic3r/GUI/ImGuiWrapper.hpp b/src/slic3r/GUI/ImGuiWrapper.hpp
index 6b584a60c..5280b876b 100644
--- a/src/slic3r/GUI/ImGuiWrapper.hpp
+++ b/src/slic3r/GUI/ImGuiWrapper.hpp
@@ -223,7 +223,7 @@ private:
     void render_draw_data(ImDrawData *draw_data);
     bool display_initialized() const;
     void destroy_font();
-    std::vector<unsigned char> load_svg(const std::string& bitmap_name, unsigned target_width, unsigned target_height);
+    std::vector<unsigned char> load_svg(const std::string& bitmap_name, unsigned target_width, unsigned target_height, unsigned *outwidth, unsigned *outheight);
 
     static const char* clipboard_get(void* user_data);
     static void clipboard_set(void* user_data, const char* text);