Bug 1403230: Block WRusr.dll in child processes when using Alternate Desktop. r=jimm

security/sandbox/win/src/sandboxbroker/sandboxBroker.cpp

@@ -28,6 +28,11 @@
 #include "sandbox/win/src/security_level.h"
 #include "WinUtils.h"
 
+// We're just blocking one DLL for the moment because of problems with the
+// Alternate Desktop. If and when we expand this we'll make this a static list
+// and add checking to see if DLL is loaded in the parent.
+#define WEBROOT_DLL L"WRusr.dll"
+
 namespace mozilla
 {
 
@@ -432,6 +437,12 @@ SandboxBroker::SetSecurityLevelForContentProcess(int32_t aSandboxLevel,
     MOZ_RELEASE_ASSERT(sandbox::SBOX_ALL_OK == result,
                        "Failed to create alternate desktop for sandbox.");
 
+    // Webroot SecureAnywhere causes crashes when we use an Alternate Desktop,
+    // so block the DLL from loading in the child process. (bug 1400637)
+    result = mPolicy->AddDllToUnload(WEBROOT_DLL);
+    MOZ_RELEASE_ASSERT(sandbox::SBOX_ALL_OK == result,
+                       "AddDllToUnload should never fail, what happened?");
+
     mitigations |= sandbox::MITIGATION_IMAGE_LOAD_NO_LOW_LABEL;
     // If we're running from a network drive then we can't block loading from
     // remote locations.
@@ -804,6 +815,12 @@ SandboxBroker::SetSecurityLevelForGMPlugin(SandboxLevel aLevel)
   SANDBOX_ENSURE_SUCCESS(result,
                          "Failed to create alternate desktop for sandbox.");
 
+  // Webroot SecureAnywhere causes crashes when we use an Alternate Desktop,
+  // so block the DLL from loading in the child process. (bug 1400637)
+  result = mPolicy->AddDllToUnload(WEBROOT_DLL);
+  MOZ_RELEASE_ASSERT(sandbox::SBOX_ALL_OK == result,
+                     "AddDllToUnload should never fail, what happened?");
+
   result = mPolicy->SetIntegrityLevel(sandbox::INTEGRITY_LEVEL_LOW);
   MOZ_ASSERT(sandbox::SBOX_ALL_OK == result,
              "SetIntegrityLevel should never fail with these arguments, what happened?");