From ce57a45c1132b1595b43751f86f3be505107dae8 Mon Sep 17 00:00:00 2001
From: tanyifeng <tanyifeng1@huawei.com>
Date: Thu, 21 Mar 2019 15:48:02 +0800
Subject: [PATCH 069/131] lxc: killall processes if container shared pid
 namespace

Signed-off-by: tanyifeng <tanyifeng1@huawei.com>
Signed-off-by: LiFeng <lifeng68@huawei.com>
---
 src/lxc/cgroups/cgfsng.c |   2 +-
 src/lxc/start.c          | 160 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 161 insertions(+), 1 deletion(-)

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index e5132182..ab7ca35e 100644
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -1056,7 +1056,7 @@ static int cgroup_rmdir(struct hierarchy **hierarchies,
 
 		ret = recursive_destroy(h->container_full_path);
 		if (ret < 0) {
-			ERROR("Failed to destroy \"%s\"", h->container_full_path);
+			SYSERROR("Failed to destroy \"%s\"", h->container_full_path);
 			return -1;
 		}
 
diff --git a/src/lxc/start.c b/src/lxc/start.c
index cad0d769..1c9eb0ab 100644
--- a/src/lxc/start.c
+++ b/src/lxc/start.c
@@ -2494,6 +2494,162 @@ static void clean_resource_set_env(struct lxc_handler *handler)
 	/* End of environment variable setup for hooks. */
 }
 
+void trim_line(char *s)
+{
+	size_t len;
+
+	len = strlen(s);
+	while ((len > 1) && (s[len - 1] == '\n'))
+		s[--len] = '\0';
+}
+
+static int _read_procs_file(const char *path, pid_t **pids, size_t *len)
+{
+	FILE *f;
+	char *line = NULL;
+	size_t sz = 0;
+
+	f = fopen_cloexec(path, "r");
+	if (!f)
+		return -1;
+
+	while (getline(&line, &sz, f) != -1) {
+		pid_t pid;
+		trim_line(line);
+		pid = (pid_t)atoll(line);
+		*pids = realloc(*pids, sizeof(pid_t) * (*len + 1));
+		(*pids)[*len] = pid;
+		(*len)++;
+	}
+
+	free(line);
+	fclose(f);
+	return 0;
+}
+
+static int _recursive_read_cgroup_procs(const char *dirpath, pid_t **pids, size_t *len)
+{
+	struct dirent *direntp;
+	DIR *dir;
+	int ret, failed = 0;
+	char pathname[PATH_MAX];
+
+	dir = opendir(dirpath);
+	if (!dir && errno != ENOENT) {
+		WARN("Failed to open \"%s\"", dirpath);
+		return 0;
+	}
+
+	while ((direntp = readdir(dir))) {
+		struct stat mystat;
+		int rc;
+
+		if (!strcmp(direntp->d_name, ".") ||
+		    !strcmp(direntp->d_name, ".."))
+			continue;
+
+		rc = snprintf(pathname, PATH_MAX, "%s/%s", dirpath, direntp->d_name);
+		if (rc < 0 || rc >= PATH_MAX) {
+			failed = 1;
+			continue;
+		}
+
+		if (strcmp(direntp->d_name, "cgroup.procs") == 0) {
+			if (_read_procs_file(pathname, pids, len)) {
+				failed = 1;
+
+			}
+			continue;
+		}
+
+		ret = lstat(pathname, &mystat);
+		if (ret) {
+			failed = 1;
+			continue;
+		}
+
+		if (S_ISDIR(mystat.st_mode)) {
+			if (_recursive_read_cgroup_procs(pathname, pids, len) < 0)
+				failed = 1;
+		}
+	}
+
+	ret = closedir(dir);
+	if (ret) {
+		WARN("Failed to close directory \"%s\"", dirpath);
+		failed = 1;
+	}
+
+	return failed ? -1 : 0;
+}
+
+int get_all_pids(struct cgroup_ops *cg_ops, pid_t **pids, size_t *len)
+{
+	char *devices_path = NULL;
+	int ret;
+
+	devices_path = must_make_path("/sys/fs/cgroup", "devices", cg_ops->container_cgroup, NULL);
+	if (!file_exists(devices_path)) {
+		free(devices_path);
+		return 0;
+	}
+
+	ret = _recursive_read_cgroup_procs(devices_path, pids, len);
+	free(devices_path);
+	return ret;
+}
+
+static int set_cgroup_freezer(struct cgroup_ops *cg_ops, const char *value)
+{
+	char *fullpath;
+	int ret;
+
+	fullpath = must_make_path("/sys/fs/cgroup", "freezer", cg_ops->container_cgroup, "freezer.state", NULL);
+	ret = lxc_write_to_file(fullpath, value, strlen(value), false, 0666);
+	free(fullpath);
+	return ret;
+}
+
+/* isulad: kill all process in container cgroup path */
+static void signal_all_processes(struct lxc_handler *handler)
+{
+	int ret;
+	struct cgroup_ops *cg_ops = handler->cgroup_ops;
+	pid_t *pids = NULL;
+	size_t len = 0, i;
+
+	ret = set_cgroup_freezer(cg_ops, "FROZEN");
+	if (ret < 0 && errno != ENOENT) {
+		WARN("cgroup_set frozen failed");
+	}
+
+	ret = get_all_pids(cg_ops, &pids, &len);
+	if (ret < 0) {
+		WARN("failed to get all pids");
+	}
+
+	for (i = 0; i < len; i++) {
+		ret = kill(pids[i], SIGKILL);
+		if (ret < 0 && errno != ESRCH) {
+			WARN("Can not kill process (pid=%d) with SIGKILL for container %s", pids[i], handler->name);
+		}
+	}
+
+	ret = set_cgroup_freezer(cg_ops, "THAWED");
+	if (ret < 0 && errno != ENOENT) {
+		WARN("cgroup_set thawed failed");
+	}
+
+	for (i = 0; i < len; i++) {
+		ret = lxc_wait_for_pid_status(pids[i]);
+		if (ret < 0 && errno != ECHILD) {
+			WARN("Failed to wait pid %d for container %s: %s", pids[i], handler->name, strerror(errno));
+		}
+	}
+
+	free(pids);
+}
+
 /*isulad: do_lxcapi_clean_resource */
 int do_lxcapi_clean_resource(char *name, char *lxcpath, struct lxc_conf *conf, pid_t pid)
 {
@@ -2510,6 +2666,10 @@ int do_lxcapi_clean_resource(char *name, char *lxcpath, struct lxc_conf *conf, p
 	}
 
 	clean_resource_set_env(handler);
+	// if we shared pid namespace with others, should kill all processes within container cgroup
+	if (handler->conf->ns_share[LXC_NS_PID] != NULL) {
+		signal_all_processes(handler);
+	}
 
 	char* oci_hook_args[1];
 	oci_hook_args[0] = alloca(strlen(handler->lxcpath) + 1);
-- 
2.23.0

