cgfsng: make trim() safer

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index 2b772e2d46e789ca972c772b64c328aabcefaa6c..5ad874e82785e7dda013372b89477ea5ce46028a 100644 (file)
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -986,7 +986,7 @@ static void get_existing_subsystems(char ***klist, char ***nlist)
 static void trim(char *s)
 {
        size_t len = strlen(s);
-       while (s[len-1] == '\n')
+       while ((len > 1) && (s[len - 1] == '\n'))
                s[--len] = '\0';
 }