diff --git a/utils/aosp b/utils/aosp
index fd892e5..056c6da 100755
--- a/utils/aosp
+++ b/utils/aosp
@@ -44,7 +44,7 @@ if [ $uid -ne "0" ]; then
     AOSP_HOST_ID_ARGS="-e USER_ID=$uid -e GROUP_ID=$(id -g)"
 fi
 
-if [ -n "$SSH_AUTH_SOCK" ]; then
+if [ -S "$SSH_AUTH_SOCK" ]; then
     SSH_AUTH_ARGS="-v $SSH_AUTH_SOCK:/tmp/ssh_auth -e SSH_AUTH_SOCK=/tmp/ssh_auth"
 fi