From 7481c148ac71e822d2a211c6055070b36275b38a Mon Sep 17 00:00:00 2001
From: Easton Pillay <easton@planeteaston.com>
Date: Wed, 12 Jan 2022 15:54:12 -0600
Subject: [PATCH] Added check for maximum size of downloaded file names (#1842)

---
 src/AppInstallerCLICore/Workflows/DownloadFlow.cpp | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/AppInstallerCLICore/Workflows/DownloadFlow.cpp b/src/AppInstallerCLICore/Workflows/DownloadFlow.cpp
index 06fca0ad86..c8b4c61c17 100644
--- a/src/AppInstallerCLICore/Workflows/DownloadFlow.cpp
+++ b/src/AppInstallerCLICore/Workflows/DownloadFlow.cpp
@@ -63,10 +63,11 @@ namespace AppInstaller::CLI::Workflow
         {
             // Get file name from download URI
             std::filesystem::path filename = GetFileNameFromURI(context.Get<Execution::Data::Installer>()->Url);
+            std::wstring_view installerExtension = GetInstallerFileExtension(context);
 
-            // Assuming that we find a stem value in the URI, use it.
+            // Assuming that we find a safe stem value in the URI, use it.
             // This should be extremely common, but just in case fall back to the older name style.
-            if (filename.has_stem())
+            if (filename.has_stem() && ((filename.string().size() + installerExtension.size()) < MAX_PATH))
             {
                 filename = filename.stem();
             }
@@ -76,7 +77,7 @@ namespace AppInstaller::CLI::Workflow
                 filename = Utility::ConvertToUTF16(manifest.Id + '.' + manifest.Version);
             }
 
-            filename += GetInstallerFileExtension(context);
+            filename += installerExtension;
 
             return filename;
         }