diff --git a/tools/update-packaging/common.sh b/tools/update-packaging/common.sh
index 4b994f30169c..397ed21e2565 100755
--- a/tools/update-packaging/common.sh
+++ b/tools/update-packaging/common.sh
@@ -92,8 +92,8 @@ make_add_instruction() {
 check_for_add_if_not_update() {
   add_if_not_file_chk="$1"
 
-  if [ `basename $add_if_not_file_chk` = "channel-prefs.js" -o \
-       `basename $add_if_not_file_chk` = "update-settings.ini" ]; then
+  if [ "$(basename "$add_if_not_file_chk")" = "channel-prefs.js" -o \
+       "$(basename "$add_if_not_file_chk")" = "update-settings.ini" ]; then
     ## "true" *giggle*
     return 0;
   fi
diff --git a/tools/update-packaging/make_incremental_update.sh b/tools/update-packaging/make_incremental_update.sh
index 24d68616731a..31b74813e50e 100755
--- a/tools/update-packaging/make_incremental_update.sh
+++ b/tools/update-packaging/make_incremental_update.sh
@@ -166,7 +166,7 @@ for ((i=0; $i<$num_oldfiles; i=$i+1)); do
 
     if check_for_add_if_not_update "$f"; then
       # The full workdir may not exist yet, so create it if necessary.
-      mkdir -p `dirname "$workdir/$f"`
+      mkdir -p "$(dirname "$workdir/$f")"
       $XZ $XZ_OPT --compress $BCJ_OPTIONS --lzma2 --format=xz --check=crc64 --force --stdout "$newdir/$f" > "$workdir/$f"
       copy_perm "$newdir/$f" "$workdir/$f"
       make_add_if_not_instruction "$f" "$updatemanifestv3"
@@ -176,7 +176,7 @@ for ((i=0; $i<$num_oldfiles; i=$i+1)); do
 
     if check_for_forced_update "$requested_forced_updates" "$f"; then
       # The full workdir may not exist yet, so create it if necessary.
-      mkdir -p `dirname "$workdir/$f"`
+      mkdir -p "$(dirname "$workdir/$f")"
       $XZ $XZ_OPT --compress $BCJ_OPTIONS --lzma2 --format=xz --check=crc64 --force --stdout "$newdir/$f" > "$workdir/$f"
       copy_perm "$newdir/$f" "$workdir/$f"
       make_add_instruction "$f" "$updatemanifestv3" 1
diff --git a/tools/update-packaging/test/common.sh b/tools/update-packaging/test/common.sh
index ad88da2203af..0e1857c8b208 100755
--- a/tools/update-packaging/test/common.sh
+++ b/tools/update-packaging/test/common.sh
@@ -77,8 +77,8 @@ make_add_instruction() {
 check_for_add_if_not_update() {
   add_if_not_file_chk="$1"
 
-  if [ `basename $add_if_not_file_chk` = "channel-prefs.js" -o \
-       `basename $add_if_not_file_chk` = "update-settings.ini" ]; then
+  if [ "$(basename "$add_if_not_file_chk")" = "channel-prefs.js" -o \
+       "$(basename "$add_if_not_file_chk")" = "update-settings.ini" ]; then
     ## "true" *giggle*
     return 0;
   fi
@@ -89,7 +89,7 @@ check_for_add_if_not_update() {
 check_for_add_to_manifestv2() {
   add_if_not_file_chk="$1"
 
-  if [ `basename $add_if_not_file_chk` = "update-settings.ini" ]; then
+  if [ "$(basename "$add_if_not_file_chk")" = "update-settings.ini" ]; then
     ## "true" *giggle*
     return 0;
   fi