iSulad/0061-check-file-system-ro-before-merge-network-for-syscon.patch

From fa7428d0baf2c310c852b1ece41736b21ea441f9 Mon Sep 17 00:00:00 2001
From: zhangxiaoyu <zhangxiaoyu58@huawei.com>
Date: Fri, 9 Dec 2022 17:26:10 +0800
Subject: [PATCH 61/65] check file system ro before merge network for
 syscontainer

Signed-off-by: zhangxiaoyu <zhangxiaoyu58@huawei.com>
---
 .../executor/container_cb/execution_network.c | 29 +++++++++++++++++++
 src/utils/cutils/utils_fs.c                   | 27 +++++++++++++++++
 src/utils/cutils/utils_fs.h                   |  1 +
 3 files changed, 57 insertions(+)

diff --git a/src/daemon/executor/container_cb/execution_network.c b/src/daemon/executor/container_cb/execution_network.c
index bbc35e80..b738d02f 100644
--- a/src/daemon/executor/container_cb/execution_network.c
+++ b/src/daemon/executor/container_cb/execution_network.c
@@ -761,9 +761,38 @@ out:
     return ret;
 }
 
+static int check_readonly_fs_for_etc(const char *rootfs, bool *ro)
+{
+    char *path = NULL;
+
+    if (util_realpath_in_scope(rootfs, "/etc", &path) < 0) {
+        SYSERROR("Failed to get real path '/etc' under rootfs '%s'", rootfs);
+        isulad_set_error_message("Failed to get real path '/etc' under rootfs '%s'", rootfs);
+        return -1;
+    }
+
+    *ro = util_check_readonly_fs(path);
+
+    free(path);
+    return 0;
+}
+
+// modify network file in rootfs
+// make sure network file saved if rootfs migrate to another host
 static int merge_network_for_syscontainer(const host_config *host_spec, const char *rootfs, const char *hostname)
 {
     int ret = 0;
+    bool ro = false;
+
+    if (check_readonly_fs_for_etc(rootfs, &ro) != 0) {
+        ERROR("Failed to check network path");
+        return -1;
+    }
+
+    if (ro) {
+        WARN("Readonly filesystem for etc under %s. Skip merge network for syscontainer", rootfs);
+        return 0;
+    }
 
     ret = write_hostname_to_file(rootfs, hostname);
     if (ret) {
diff --git a/src/utils/cutils/utils_fs.c b/src/utils/cutils/utils_fs.c
index 218e2fe8..e7165f26 100644
--- a/src/utils/cutils/utils_fs.c
+++ b/src/utils/cutils/utils_fs.c
@@ -22,6 +22,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <sys/types.h>
+#include <sys/statvfs.h>
 #include <linux/magic.h>
 #include <sys/statfs.h>
 #include <dirent.h>
@@ -620,3 +621,29 @@ child_out:
 cleanup:
     return ret;
 }
+
+bool util_check_readonly_fs(const char *path)
+{
+    int i;
+    const int max_retry = 10;
+    struct statfs fsbuf;
+
+    for (i = 0; i < max_retry; i++) {
+        if (statfs(path, &fsbuf) == 0) {
+            break;
+        }
+        if (errno == EINTR) {
+            continue;
+        }
+
+        ERROR("Stat fs failed: %s", strerror(errno));
+        return false;
+    }
+
+    if (i >= max_retry) {
+        ERROR("Too much interrupted");
+        return false;
+    }
+
+    return (fsbuf.f_flags & ST_RDONLY) != 0;
+}
diff --git a/src/utils/cutils/utils_fs.h b/src/utils/cutils/utils_fs.h
index 6ab6b78e..6ad64a1a 100644
--- a/src/utils/cutils/utils_fs.h
+++ b/src/utils/cutils/utils_fs.h
@@ -38,6 +38,7 @@ int util_ensure_mounted_as(const char *dst, const char *mntopts);
 int util_mount_from(const char *base, const char *src, const char *dst, const char *mtype, const char *mntopts);
 typedef int (*mount_info_call_back_t)(const char *, const char *);
 bool util_deal_with_mount_info(mount_info_call_back_t cb, const char *);
+bool util_check_readonly_fs(const char *path);
 #ifdef __cplusplus
 }
 #endif
-- 
2.25.1