diff --git a/src/install.sh b/src/install.sh
index ee6a69b..23959d5 100644
--- a/src/install.sh
+++ b/src/install.sh
@@ -58,7 +58,7 @@ downloadFile() {
   local url="$1"
   local base="$2"
   local name="$3"
-  local msg rc total total_mb progress name
+  local msg rc total size progress
 
   local dest="$STORAGE/$base.tmp"
   rm -f "$dest"
@@ -88,9 +88,9 @@ downloadFile() {
 
   if (( rc == 0 )) && [ -f "$dest" ]; then
     total=$(stat -c%s "$dest")
-    total_gb=$(formatBytes "$total")
+    size=$(formatBytes "$total")
     if [ "$total" -lt 100000 ]; then
-      error "Invalid image file: is only $total_gb ?" && return 1
+      error "Invalid image file: is only $size ?" && return 1
     fi
     html "Download finished successfully..."
     mv -f "$dest" "$STORAGE/$base"
@@ -173,8 +173,10 @@ convertImage() {
       # Work around qemu-img bug
       cur_size=$(stat -c%s "$tmp_file")
       cur_gb=$(formatBytes "$cur_size")
-      if ! fallocate -l "$cur_size" "$tmp_file"; then
-        error "Failed to allocate $cur_gb for image!"
+      if ! fallocate -l "$cur_size" "$tmp_file" &>/dev/null; then
+        if ! fallocate -l -x "$cur_size" "$tmp_file"; then
+          error "Failed to allocate $cur_gb for image!"
+        fi
       fi
     fi
   fi