From ca99fb8f65f3ea249c56fb6dccefffb54e87696e Mon Sep 17 00:00:00 2001
From: Mathias Agopian <mathias@google.com>
Date: Wed, 14 Apr 2010 16:43:44 -0700
Subject: [PATCH] fix [2594950] Flash: Zooming in on some content crashes the
 Nexus One and causes it to reboot (runtime restart)

We now limit the size of the surface to the maximum size supported by the GPU.
On Nexus One this will 2048 -- it could be different on other devices.
Surface creation fails if the limit is exceeded.

Change-Id: I9ecfc2e9c58c9e283782b61ebfc6b590f71df785
---
 .../DisplayHardware/DisplayHardware.cpp         |  8 ++++++++
 .../DisplayHardware/DisplayHardware.h           |  4 ++++
 libs/surfaceflinger/Layer.cpp                   | 17 +++++++++++++++--
 3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/libs/surfaceflinger/DisplayHardware/DisplayHardware.cpp b/libs/surfaceflinger/DisplayHardware/DisplayHardware.cpp
index 59696172f..ea6835282 100644
--- a/libs/surfaceflinger/DisplayHardware/DisplayHardware.cpp
+++ b/libs/surfaceflinger/DisplayHardware/DisplayHardware.cpp
@@ -90,6 +90,8 @@ float DisplayHardware::getRefreshRate() const   { return mRefreshRate; }
 int DisplayHardware::getWidth() const           { return mWidth; }
 int DisplayHardware::getHeight() const          { return mHeight; }
 PixelFormat DisplayHardware::getFormat() const  { return mFormat; }
+uint32_t DisplayHardware::getMaxTextureSize() const { return mMaxTextureSize; }
+uint32_t DisplayHardware::getMaxViewportDims() const { return mMaxViewportDims; }
 
 void DisplayHardware::init(uint32_t dpy)
 {
@@ -246,6 +248,11 @@ void DisplayHardware::init(uint32_t dpy)
     LOGI("version   : %s", glGetString(GL_VERSION));
     LOGI("extensions: %s", gl_extensions);
 
+    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &mMaxTextureSize);
+    glGetIntegerv(GL_MAX_VIEWPORT_DIMS, &mMaxViewportDims);
+    LOGI("GL_MAX_TEXTURE_SIZE = %d", mMaxTextureSize);
+    LOGI("GL_MAX_VIEWPORT_DIMS = %d", mMaxViewportDims);
+
 #if 0
     // for drivers that don't have proper support for flushing cached buffers
     // on gralloc unlock, uncomment this block and test for the specific
@@ -273,6 +280,7 @@ void DisplayHardware::init(uint32_t dpy)
 #warning "EGL_ANDROID_image_native_buffer not supported"
 #endif
 
+
     // Unbind the context from this thread
     eglMakeCurrent(display, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
 
diff --git a/libs/surfaceflinger/DisplayHardware/DisplayHardware.h b/libs/surfaceflinger/DisplayHardware/DisplayHardware.h
index 6914d0cde..df046af95 100644
--- a/libs/surfaceflinger/DisplayHardware/DisplayHardware.h
+++ b/libs/surfaceflinger/DisplayHardware/DisplayHardware.h
@@ -76,6 +76,8 @@ public:
     PixelFormat getFormat() const;
     uint32_t    getFlags() const;
     void        makeCurrent() const;
+    uint32_t    getMaxTextureSize() const;
+    uint32_t    getMaxViewportDims() const;
 
     uint32_t getPageFlipCount() const;
     EGLDisplay getEGLDisplay() const { return mDisplay; }
@@ -104,6 +106,8 @@ private:
     PixelFormat     mFormat;
     uint32_t        mFlags;
     mutable uint32_t mPageFlipCount;
+    GLint           mMaxViewportDims;
+    GLint           mMaxTextureSize;
     
     sp<FramebufferNativeWindow> mNativeWindow;
     overlay_control_device_t* mOverlayEngine;
diff --git a/libs/surfaceflinger/Layer.cpp b/libs/surfaceflinger/Layer.cpp
index 4dc4a153e..0a3254dec 100644
--- a/libs/surfaceflinger/Layer.cpp
+++ b/libs/surfaceflinger/Layer.cpp
@@ -41,6 +41,10 @@
 
 namespace android {
 
+template <typename T> inline T min(T a, T b) {
+    return a<b ? a : b;
+}
+
 // ---------------------------------------------------------------------------
 
 const uint32_t Layer::typeInfo = LayerBaseClient::typeInfo | 4;
@@ -109,17 +113,26 @@ status_t Layer::setBuffers( uint32_t w, uint32_t h,
 
     // the display's pixel format
     const DisplayHardware& hw(graphicPlane(0).displayHardware());
+    uint32_t const maxSurfaceDims = min(
+            hw.getMaxTextureSize(), hw.getMaxViewportDims());
+
+    // never allow a surface larger than what our underlying GL implementation
+    // can handle.
+    if ((uint32_t(w)>maxSurfaceDims) || (uint32_t(h)>maxSurfaceDims)) {
+        return BAD_VALUE;
+    }
+
     PixelFormatInfo displayInfo;
     getPixelFormatInfo(hw.getFormat(), &displayInfo);
     const uint32_t hwFlags = hw.getFlags();
     
     mFormat = format;
-    mWidth = w;
+    mWidth  = w;
     mHeight = h;
     mSecure = (flags & ISurfaceComposer::eSecure) ? true : false;
     mNeedsBlending = (info.h_alpha - info.l_alpha) > 0;
     mNoEGLImageForSwBuffers = !(hwFlags & DisplayHardware::CACHED_BUFFERS);
-    
+
     // we use the red index
     int displayRedSize = displayInfo.getSize(PixelFormatInfo::INDEX_RED);
     int layerRedsize = info.getSize(PixelFormatInfo::INDEX_RED);