From 4c78990dd39bcd8be50d9fd4b819cd70be82c884 Mon Sep 17 00:00:00 2001
From: Sebastian Wick <sebastian.wick@redhat.com>
Date: Thu, 2 Jul 2026 20:11:36 +0200
Subject: [PATCH] dir-utils: Fix signed integer overflow in extension priority
 comparator

The subtraction-based comparison overflows when priority values are far
apart, which is undefined behavior in C.
---
 common/flatpak-dir-utils.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/common/flatpak-dir-utils.c b/common/flatpak-dir-utils.c
index 4a23df83c..c5dd3e933 100644
--- a/common/flatpak-dir-utils.c
+++ b/common/flatpak-dir-utils.c
@@ -338,7 +338,13 @@ flatpak_extension_compare (gconstpointer _a,
   const FlatpakExtension *a = _a;
   const FlatpakExtension *b = _b;
 
-  return b->priority - a->priority;
+  /* Subtraction would overflow for far-apart priorities */
+  if (b->priority > a->priority)
+    return 1;
+  else if (b->priority < a->priority)
+    return -1;
+  else
+    return 0;
 }
 
 static FlatpakExtension *