From 4c79f9bc2037e08fa14cb538d19dd43299c17c6d Mon Sep 17 00:00:00 2001
From: Sergei Dmitrouk <sergei@posteo.net>
Date: Wed, 19 May 2021 00:09:41 +0800
Subject: [PATCH] MdeModulePkg/PciBusDxe: Fix possible uninitialized use

If the function gets invalid value for the `ResizableBarOp` parameter
and asserts are disabled, `Bit` can be used uninitialized.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Signed-off-by: Sergei Dmitrouk <sergei@posteo.net>
Reviewed-by: Hao A Wu <hao.a.wu@intel.com>
---
 MdeModulePkg/Bus/Pci/PciBusDxe/PciLib.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciLib.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciLib.c
index 6bba283671..4caac56f1d 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciLib.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciLib.c
@@ -1778,10 +1778,9 @@ PciProgramResizableBar (
 
     if (ResizableBarOp == PciResizableBarMax) {
       Bit = HighBitSet64(Capabilities);
-    } else if (ResizableBarOp == PciResizableBarMin) {
-      Bit = LowBitSet64(Capabilities);
     } else {
-      ASSERT ((ResizableBarOp == PciResizableBarMax) || (ResizableBarOp == PciResizableBarMin));
+      ASSERT (ResizableBarOp == PciResizableBarMin);
+      Bit = LowBitSet64(Capabilities);
     }
 
     ASSERT (Bit >= 0);
-- 
2.39.2