diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index 389c5eeb5d..636307bedf 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -84,7 +84,7 @@ static ssize_t ga_pipe_read_str(int fd[2], char **str)
         *str = g_realloc(*str, len + n + 1);
         memcpy(*str + len, buf, n);
         len += n;
-        *str[len] = '\0';
+        (*str)[len] = '\0';
     }
     close(fd[0]);
     fd[0] = -1;