From: Christian Brauner <christian.brauner@ubuntu.com>
Date: Sat, 7 Dec 2019 23:16:59 +0000 (+0100)
Subject: cgroups/cgfsng: rework cgfsng_escape()
X-Git-Tag: lxc-4.0.0~78^2~12
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=52d08ab033460d704466bf34b7b84ced3a1d7905;p=thirdparty%2Flxc.git

cgroups/cgfsng: rework cgfsng_escape()

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

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index 1638f5d52..932425e81 100644
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -1930,23 +1930,33 @@ __cgfsng_ops static int cgfsng_nrtasks(struct cgroup_ops *ops)
 
 /* Only root needs to escape to the cgroup of its init. */
 __cgfsng_ops static bool cgfsng_escape(const struct cgroup_ops *ops,
-					 struct lxc_conf *conf)
+				       struct lxc_conf *conf)
 {
-	if (conf->cgroup_meta.relative || geteuid() || !ops->hierarchies)
+	if (!ops)
+		return ret_set_errno(false, ENOENT);
+
+	if (!ops->hierarchies)
+		return true;
+
+	if (!conf)
+		return ret_set_errno(false, EINVAL);
+
+	if (conf->cgroup_meta.relative || geteuid())
 		return true;
 
 	for (int i = 0; ops->hierarchies[i]; i++) {
-		int ret;
 		__do_free char *fullpath = NULL;
+		int ret;
 
-		fullpath = must_make_path(ops->hierarchies[i]->mountpoint,
-					  ops->hierarchies[i]->container_base_path,
-					  "cgroup.procs", NULL);
+		fullpath =
+		    must_make_path(ops->hierarchies[i]->mountpoint,
+				   ops->hierarchies[i]->container_base_path,
+				   "cgroup.procs", NULL);
 		ret = lxc_write_to_file(fullpath, "0", 2, false, 0666);
-		if (ret != 0) {
-			SYSERROR("Failed to escape to cgroup \"%s\"", fullpath);
-			return false;
-		}
+		if (ret != 0)
+			return log_error_errno(false,
+					       errno, "Failed to escape to cgroup \"%s\"",
+					       fullpath);
 	}
 
 	return true;