diff --git a/ext/fileinfo/generate_patch.sh b/ext/fileinfo/generate_patch.sh
index da99b1fcdb2af..4e3fade8ec566 100755
--- a/ext/fileinfo/generate_patch.sh
+++ b/ext/fileinfo/generate_patch.sh
@@ -3,7 +3,7 @@
 VERSION=5.45
 
 # Go to fileinfo extension directory.
-cd $(CDPATH= cd -- "$(dirname -- "$0")" && pwd -P)
+cd "$(CDPATH='' cd -- "$(dirname -- "$0")" && pwd -P)" || exit
 
 if [ ! -d libmagic.orig ]; then
   mkdir libmagic.orig