From 259f249756e9e67827ab1d53ac31cd985cd7d539 Mon Sep 17 00:00:00 2001
From: LiFeng <lifeng68@huawei.com>
Date: Wed, 22 May 2019 23:00:17 -0400
Subject: [PATCH 100/131] start: add check save pid info file

Signed-off-by: LiFeng <lifeng68@huawei.com>
---
 src/lxc/start.c | 72 ++++++++++++++++++++++++++++++++++++++++++-------
 src/lxc/utils.c |  2 +-
 src/lxc/utils.h |  1 +
 3 files changed, 64 insertions(+), 11 deletions(-)

diff --git a/src/lxc/start.c b/src/lxc/start.c
index 3657d4eb..45417930 100644
--- a/src/lxc/start.c
+++ b/src/lxc/start.c
@@ -1850,14 +1850,10 @@ static inline int do_share_ns(void *arg)
 	return 0;
 }
 
-/* isuald: save pid/ppid info */
-static int lxc_save_container_info(char *filename, pid_t pid)
+static int lxc_write_container_info(char *filename, pid_t pid, pid_t p_pid, unsigned long long start_at, unsigned long long p_start_at)
 {
 	FILE *pid_fp = NULL;
 	int ret = 0;
-	pid_t p_pid = 0;
-	unsigned long long start_at = 0;
-	unsigned long long p_start_at = 0;
 
 	pid_fp = fopen(filename, "w");
 	if (pid_fp == NULL) {
@@ -1866,11 +1862,6 @@ static int lxc_save_container_info(char *filename, pid_t pid)
 		goto out;
 	}
 
-	start_at = lxc_get_process_startat(pid);
-
-	p_pid = getpid();
-	p_start_at = lxc_get_process_startat(p_pid);
-
 	if (fprintf(pid_fp, "%d %llu %d %llu\n", pid, start_at, p_pid, p_start_at) < 0) {
 		SYSERROR("Failed to write '%s'", filename);
 		ret = -1;
@@ -1883,6 +1874,67 @@ out:
 	return ret;
 }
 
+static int lxc_check_container_info(char *filename, pid_t pid, pid_t p_pid, unsigned long long start_at, unsigned long long p_start_at)
+{
+	int ret = 0;
+	int num;
+	char sbuf[1024] = {0}; /* bufs for stat */
+	int saved_pid;		/* process id */
+	int saved_ppid;		/* pid of parent process */
+	unsigned long long saved_start_time;	/* start time of process -- seconds since 1-1-70 */
+	unsigned long long saved_pstart_time;	/* start time of parent process -- seconds since 1-1-70 */
+
+	if ((lxc_file2str(filename, sbuf, sizeof(sbuf))) == -1) {
+		SYSERROR("Failed to read pidfile %s", filename);
+		ret = -1;
+		goto out;
+	}
+
+	num = sscanf(sbuf, "%d %Lu %d %Lu", &saved_pid, &saved_start_time, &saved_ppid, &saved_pstart_time);
+	if (num < 0) {
+		SYSERROR("Call sscanf error");
+		ret = -1;
+		goto out;
+	}
+
+	if (pid != saved_pid || p_pid != saved_ppid
+		|| start_at != saved_start_time || p_start_at != saved_pstart_time) {
+		ERROR("Check container info failed");
+		ret = -1;
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
+
+/* isuald: save pid/ppid info */
+static int lxc_save_container_info(char *filename, pid_t pid)
+{
+	int ret = 0;
+	pid_t p_pid = 0;
+	unsigned long long start_at = 0;
+	unsigned long long p_start_at = 0;
+
+	start_at = lxc_get_process_startat(pid);
+	p_pid = getpid();
+	p_start_at = lxc_get_process_startat(p_pid);
+
+	ret = lxc_write_container_info(filename, pid, p_pid, start_at, p_start_at);
+	if (ret != 0) {
+		goto out;
+	}
+
+	ret = lxc_check_container_info(filename, pid, p_pid, start_at, p_start_at);
+	if (ret != 0) {
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
 /* lxc_spawn() performs crucial setup tasks and clone()s the new process which
  * exec()s the requested container binary.
  * Note that lxc_spawn() runs in the parent namespaces. Any operations performed
diff --git a/src/lxc/utils.c b/src/lxc/utils.c
index fd6075f8..dc0e6c51 100644
--- a/src/lxc/utils.c
+++ b/src/lxc/utils.c
@@ -1909,7 +1909,7 @@ set_env:
 
 
 /* isulad: read file to buffer */
-static int lxc_file2str(const char *filename, char ret[], int cap)
+int lxc_file2str(const char *filename, char ret[], int cap)
 {
 	int fd, num_read;
 
diff --git a/src/lxc/utils.h b/src/lxc/utils.h
index 20407af8..4410ff22 100644
--- a/src/lxc/utils.h
+++ b/src/lxc/utils.h
@@ -323,5 +323,6 @@ extern void lxc_write_error_message(int errfd, const char *format, ...);
 extern bool lxc_process_alive(pid_t pid, unsigned long long start_time);
 
 extern bool is_non_negative_num(const char *s);
+extern int lxc_file2str(const char *filename, char ret[], int cap);
 
 #endif /* __LXC_UTILS_H */
-- 
2.23.0