umount: Fix mount points escaping/unescaping with Bash-4.3

completions/umount.linux

@@ -18,8 +18,8 @@ _reply_compgen_array()
 
     # We also have to add another round of escaping to $cur.
     local ecur="$cur"
-    ecur="${ecur//\\/\\\\}"
-    ecur="${ecur//\'/\'}"
+    ecur=${ecur//\\/\\\\}
+    ecur=${ecur//\'/\\\'}
 
     # Actually generate completions.
     local oldifs=$IFS
@@ -29,7 +29,7 @@ _reply_compgen_array()
 
 # Unescape strings in the linux fstab(5) format (with octal escapes).
 __linux_fstab_unescape() {
-    eval $1="'${!1//\'/\047}'"
+    eval $1="'${!1//\'/\\047}'"
     eval $1="'${!1/%\\/\\\\}'"
     eval "$1=$'${!1}'"
 }