--- a/security/sandbox/linux/SandboxOpenedFiles.cpp
+++ b/security/sandbox/linux/SandboxOpenedFiles.cpp
@@ -33,17 +33,17 @@ SandboxOpenedFile::SandboxOpenedFile(con
     mExpectError = true;
   }
   mMaybeFd = fd;
 }
 
 int
 SandboxOpenedFile::GetDesc() const
 {
-  int fd = -1;
+  int fd;
   if (mDup) {
     fd = mMaybeFd;
     if (fd >= 0) {
       fd = dup(fd);
       if (fd < 0) {
         SANDBOX_LOG_ERROR("dup: %s", strerror(errno));
       }
     }

--- a/security/sandbox/linux/broker/SandboxBrokerPolicyFactory.cpp
+++ b/security/sandbox/linux/broker/SandboxBrokerPolicyFactory.cpp
@@ -120,16 +120,19 @@ AddPathsFromFile(SandboxBroker::Policy* 
   nsCOMPtr<nsILineInputStream> lineStream(do_QueryInterface(fileStream, &rv));
   if (NS_FAILED(rv)) {
     return;
   }
   nsAutoCString line;
   bool more = true;
   do {
     rv = lineStream->ReadLine(line, &more);
+    if (NS_FAILED(rv)) {
+      break;
+    }
     // Cut off any comments at the end of the line, also catches lines
     // that are entirely a comment
     int32_t hash = line.FindChar('#');
     if (hash >= 0) {
       line = Substring(line, 0, hash);
     }
     // Simplify our following parsing by trimming whitespace
     line.CompressWhitespace(true, true);