cgroups: please compilers

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

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index effbf11a8735cb8322a2e8930d0bfbb659a2566e..b80d826f0d0d2601bd7cd396fd9f844acde014de 100644 (file)
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -2085,8 +2085,10 @@ static int cgroup_attach_leaf(const struct lxc_conf *conf, int unified_fd, pid_t
                char attach_cgroup[STRLITERALLEN(".lxc-1000/cgroup.procs") + 1];
                char *slash;
 
-               snprintf(attach_cgroup, STRLITERALLEN(".lxc-%d/cgroup.procs"),
-                        ".lxc-%d/cgroup.procs", idx);
+               ret = snprintf(attach_cgroup, sizeof(attach_cgroup), ".lxc-%d/cgroup.procs", idx);
+               if (ret < 0 || (size_t)ret >= sizeof(attach_cgroup))
+                       return ret_errno(EIO);
+
                slash = &attach_cgroup[ret] - STRLITERALLEN("/cgroup.procs");
                *slash = '\0';