fix memory leaks in cgroup functions

src/lxc/cgroup.h

@@ -23,15 +23,13 @@
 #ifndef _cgroup_h
 #define _cgroup_h
 
-#define MAXPRIOLEN 24
-
 struct lxc_handler;
 extern int lxc_cgroup_destroy(const char *cgpath);
-extern int lxc_cgroup_path_get(char **path, const char *subsystem, const char *name,
+extern char *lxc_cgroup_path_get(const char *subsystem, const char *name,
 			      const char *lxcpath);
 extern int lxc_cgroup_nrtasks(const char *cgpath);
 extern char *lxc_cgroup_path_create(const char *lxcgroup, const char *name);
 extern int lxc_cgroup_enter(const char *cgpath, pid_t pid);
 extern int lxc_cgroup_attach(pid_t pid, const char *name, const char *lxcpath);
-extern int cgroup_path_get(char **path, const char *subsystem, const char *cgpath);
+extern char *cgroup_path_get(const char *subsystem, const char *cgpath);
 #endif

src/lxc/commands.c

@@ -335,15 +335,13 @@ static int lxc_cmd_get_clone_flags_callback(int fd, struct lxc_cmd_req *req,
  * particular subsystem. This is the cgroup path relative to the root
  * of the cgroup filesystem.
  *
- * @subsystem : the cgroup subsystem of interest (i.e. freezer)
  * @name      : name of container to connect to
  * @lxcpath   : the lxcpath in which the container is running
  *
  * Returns the path on success, NULL on failure. The caller must free() the
  * returned path.
  */
-char *lxc_cmd_get_cgroup_path(const char *subsystem, const char *name,
-			      const char *lxcpath)
+char *lxc_cmd_get_cgroup_path(const char *name, const char *lxcpath)
 {
 	int ret, stopped = 0;
 	struct lxc_cmd_rr cmd = {

src/lxc/commands.h

@@ -67,8 +67,7 @@ struct lxc_cmd_console_rsp_data {
 
 extern int lxc_cmd_console(const char *name, int *ttynum, int *fd,
 			   const char *lxcpath);
-extern char *lxc_cmd_get_cgroup_path(const char *subsystem,
-				     const char *name, const char *lxcpath);
+extern char *lxc_cmd_get_cgroup_path(const char *name, const char *lxcpath);
 extern int lxc_cmd_get_clone_flags(const char *name, const char *lxcpath);
 extern char *lxc_cmd_get_config_item(const char *name, const char *item, const char *lxcpath);
 extern pid_t lxc_cmd_get_init_pid(const char *name, const char *lxcpath);

src/lxc/freezer.c

@@ -120,19 +120,16 @@ out:
 
 static int freeze_unfreeze(const char *name, int freeze, const char *lxcpath)
 {
-	char *nsgroup = NULL;
+	char *cgabspath;
 	int ret;
 
-	ret = lxc_cgroup_path_get(&nsgroup, "freezer", name, lxcpath);
-	if (ret)
-		goto fail;
-
-	return do_unfreeze(nsgroup, freeze, name, lxcpath);
-
-fail:
-	if (nsgroup)
-		free(nsgroup);
+	cgabspath = lxc_cgroup_path_get("freezer", name, lxcpath);
+	if (!cgabspath)
 		return -1;
+
+	ret = do_unfreeze(cgabspath, freeze, name, lxcpath);
+	free(cgabspath);
+	return ret;
 }
 
 int lxc_freeze(const char *name, const char *lxcpath)
@@ -146,19 +143,16 @@ int lxc_unfreeze(const char *name, const char *lxcpath)
 	return freeze_unfreeze(name, 0, lxcpath);
 }
 
-int lxc_unfreeze_bypath(const char *cgpath)
+int lxc_unfreeze_bypath(const char *cgrelpath)
 {
-	char *nsgroup = NULL;
+	char *cgabspath;
 	int ret;
 
-	ret = cgroup_path_get(&nsgroup, "freezer", cgpath);
-	if (ret)
-		goto fail;
-
-	return do_unfreeze(nsgroup, 0, NULL, NULL);
-
-fail:
-	if (nsgroup)
-		free(nsgroup);
+	cgabspath = cgroup_path_get("freezer", cgrelpath);
+	if (!cgabspath)
 		return -1;
+
+	ret = do_unfreeze(cgabspath, 0, NULL, NULL);
+	free(cgabspath);
+	return ret;
 }

src/lxc/lxccontainer.c

@@ -555,7 +555,7 @@ static bool create_container_dir(struct lxc_container *c)
  * for ->create, argv contains the arguments to pass to the template,
  * terminated by NULL.  If no arguments, you can just pass NULL.
  */
-static bool lxcapi_create(struct lxc_container *c, char *t, char *const argv[])
+static bool lxcapi_create(struct lxc_container *c, const char *t, char *const argv[])
 {
 	bool bret = false;
 	pid_t pid;
@@ -621,7 +621,7 @@ static bool lxcapi_create(struct lxc_container *c, char *t, char *const argv[])
 		newargv = malloc(nargs * sizeof(*newargv));
 		if (!newargv)
 			exit(1);
-		newargv[0] = t;
+		newargv[0] = (char *)t;
 
 		len = strlen(c->config_path) + strlen(c->name) + strlen("--path=") + 2;
 		patharg = malloc(len);
@@ -702,7 +702,7 @@ static bool lxcapi_shutdown(struct lxc_container *c, int timeout)
 	return retv;
 }
 
-static bool lxcapi_createl(struct lxc_container *c, char *t, ...)
+static bool lxcapi_createl(struct lxc_container *c, const char *t, ...)
 {
 	bool bret = false;
 	char **args = NULL, **temp;

src/lxc/lxccontainer.h

@@ -48,8 +48,8 @@ struct lxc_container {
 	bool (*set_config_item)(struct lxc_container *c, const char *key, const char *value);
 	bool (*destroy)(struct lxc_container *c);
 	bool (*save_config)(struct lxc_container *c, const char *alt_file);
-	bool (*create)(struct lxc_container *c, char *t, char *const argv[]);
-	bool (*createl)(struct lxc_container *c, char *t, ...);
+	bool (*create)(struct lxc_container *c, const char *t, char *const argv[]);
+	bool (*createl)(struct lxc_container *c, const char *t, ...);
 	/* send SIGPWR.  if timeout is not 0 or -1, do a hard stop after timeout seconds */
 	bool (*shutdown)(struct lxc_container *c, int timeout);
 	/* clear all network or capability items in the in-memory configuration */

src/lxc/state.c

@@ -69,38 +69,40 @@ lxc_state_t lxc_str2state(const char *state)
 
 static lxc_state_t freezer_state(const char *name, const char *lxcpath)
 {
-	char *nsgroup = NULL;
+	char *cgabspath = NULL;
 	char freezer[MAXPATHLEN];
 	char status[MAXPATHLEN];
 	FILE *file;
-	int err;
+	int ret;
 
-	err = lxc_cgroup_path_get(&nsgroup, "freezer", name, lxcpath);
-	if (err)
-		goto fail;
+	cgabspath = lxc_cgroup_path_get("freezer", name, lxcpath);
+	if (!cgabspath)
+		return -1;
 
-	err = snprintf(freezer, MAXPATHLEN, "%s/freezer.state", nsgroup);
-	if (err < 0 || err >= MAXPATHLEN)
-		goto fail;
+	ret = snprintf(freezer, MAXPATHLEN, "%s/freezer.state", cgabspath);
+	if (ret < 0 || ret >= MAXPATHLEN)
+		goto out;
 
 	file = fopen(freezer, "r");
-	if (!file)
-		goto fail;
+	if (!file) {
+		ret = -1;
+		goto out;
+	}
 
-	err = fscanf(file, "%s", status);
+	ret = fscanf(file, "%s", status);
 	fclose(file);
 
-	if (err == EOF) {
+	if (ret == EOF) {
 		SYSERROR("failed to read %s", freezer);
-		goto fail;
+		ret = -1;
+		goto out;
 	}
 
-	return lxc_str2state(status);
+	ret = lxc_str2state(status);
 
-fail:
-	if (nsgroup)
-		free(nsgroup);
-	return -1;
+out:
+	free(cgabspath);
+	return ret;
 }
 
 lxc_state_t lxc_getstate(const char *name, const char *lxcpath)