diff --git a/netwerk/protocol/http/HttpBaseChannel.cpp b/netwerk/protocol/http/HttpBaseChannel.cpp
index a7c3e9a58fb9..f809889d182a 100644
--- a/netwerk/protocol/http/HttpBaseChannel.cpp
+++ b/netwerk/protocol/http/HttpBaseChannel.cpp
@@ -2973,7 +2973,11 @@ HttpBaseChannel::SetupReplacementChannel(nsIURI       *newURI,
   httpChannel->SetAllowPipelining(mAllowPipelining);
   httpChannel->SetAllowSTS(mAllowSTS);
   // convey the new redirection limit
-  httpChannel->SetRedirectionLimit(mRedirectionLimit - 1);
+  // make sure we don't underflow
+  uint32_t redirectionLimit = mRedirectionLimit
+    ? mRedirectionLimit - 1
+    : 0;
+  httpChannel->SetRedirectionLimit(redirectionLimit);
 
   // convey the Accept header value
   {