commit 0a52509e8cdc6da93daab9c34fdbb63232fa8adf
author Ady Abraham <adyabr@google.com> Tue Mar 03 12:51:24 2020 -0800
committer Ady Abraham <adyabr@google.com> Wed Mar 04 20:02:55 2020 +0000
tree 1a1a84efee0347d90ac0491b092d1d49d97328d6
parent 5fad64e09b8a02d4cc14475a92aa612e38cd39f1

ISurfaceComposer: boundary check input on CAPTURE_LAYERS

Add a sanity check on numExcludeHandles to make sure we don't cause
an overflow.

Test: adb shell /data/nativetest64/SurfaceFlinger_test/SurfaceFlinger_test
Fixes: 146435753
Change-Id: I2c700392727e2f4e0e434fb4c1800f2973c7418b
Merged-In: I2c700392727e2f4e0e434fb4c1800f2973c7418b

services/surfaceflinger/SurfaceFlinger.cpp

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 27bd53c..385a093 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -367,7 +367,7 @@
     property_get("ro.sf.blurs_are_expensive", value, "0");
     mBlursAreExpensive = atoi(value);
 
-    const size_t defaultListSize = MAX_LAYERS;
+    const size_t defaultListSize = ISurfaceComposer::MAX_LAYERS;
     auto listSize = property_get_int32("debug.sf.max_igbp_list_size", int32_t(defaultListSize));
     mMaxGraphicBufferProducerListSize = (listSize > 0) ? size_t(listSize) : defaultListSize;
 
@@ -3066,9 +3066,9 @@
             parent = parentLayer;
         }
 
-        if (mNumLayers >= MAX_LAYERS) {
+        if (mNumLayers >= ISurfaceComposer::MAX_LAYERS) {
             ALOGE("AddClientLayer failed, mNumLayers (%zu) >= MAX_LAYERS (%zu)", mNumLayers.load(),
-                  MAX_LAYERS);
+                  ISurfaceComposer::MAX_LAYERS);
             return NO_MEMORY;
         }