libcgroup: open files with O_CLOEXEC

We don't want file handles to remain open across execs.
Therefore open files with the O_CLOEXEC flag which closes
the files on exec.

Signed-off-by: Dhaval Giani <dhaval.giani@gmail.com>

diff --git a/src/api.c b/src/api.c
index 53c94300b9ab5598afe5d9f703f50f6a257b7c61..4823006108ab583720b890c29ebe6ab41e09d25e 100644 (file)
--- a/src/api.c
+++ b/src/api.c
@@ -373,7 +373,7 @@ static int cgroup_parse_rules(bool cache, uid_t muid,
 
        /* Open the configuration file. */
        pthread_rwlock_wrlock(&rl_lock);
-       fp = fopen(CGRULES_CONF_FILE, "r");
+       fp = fopen(CGRULES_CONF_FILE, "re");
        if (!fp) {
                cgroup_dbg("Failed to open configuration file %s with"
                                " error: %s\n", CGRULES_CONF_FILE,
@@ -667,7 +667,7 @@ int cgroup_init(void)
 
        pthread_rwlock_wrlock(&cg_mount_table_lock);
 
-       proc_cgroup = fopen("/proc/cgroups", "r");
+       proc_cgroup = fopen("/proc/cgroups", "re");
 
        if (!proc_cgroup) {
                last_errno = errno;
@@ -705,7 +705,7 @@ int cgroup_init(void)
        }
        controllers[i] = NULL;
 
-       proc_mount = fopen("/proc/mounts", "r");
+       proc_mount = fopen("/proc/mounts", "re");
        if (proc_mount == NULL) {
                ret = ECGFAIL;
                goto unlock_exit;
@@ -832,7 +832,7 @@ static int cg_test_mounted_fs(void)
        char mntent_buff[4 * FILENAME_MAX];
        int ret = 1;
 
-       proc_mount = fopen("/proc/mounts", "r");
+       proc_mount = fopen("/proc/mounts", "re");
        if (proc_mount == NULL)
                return 0;
 
@@ -917,7 +917,7 @@ static int __cgroup_attach_task_pid(char *path, pid_t tid)
        int ret = 0;
        FILE *tasks = NULL;
 
-       tasks = fopen(path, "w");
+       tasks = fopen(path, "we");
        if (!tasks) {
                switch (errno) {
                case EPERM:
@@ -1128,7 +1128,7 @@ static int cg_set_control_value(char *path, const char *val)
        if (!cg_test_mounted_fs())
                return ECGROUPNOTMOUNTED;
 
-       control_file = fopen(path, "r+");
+       control_file = fopen(path, "r+e");
 
        if (!control_file) {
                if (errno == EPERM) {
@@ -1145,7 +1145,7 @@ static int cg_set_control_value(char *path, const char *val)
                                len--;
                        *(path+len+1) = '\0';
                        strncat(path, "tasks", sizeof(path) - strlen(path));
-                       control_file = fopen(path, "r");
+                       control_file = fopen(path, "re");
                        if (!control_file) {
                                if (errno == ENOENT)
                                        return ECGROUPSUBSYSNOTMOUNTED;
@@ -1627,7 +1627,7 @@ static int cg_delete_cgroup_controller(char *cgroup_name, char *controller,
                return ECGROUPSUBSYSNOTMOUNTED;
        strncat(path, "tasks", sizeof(path) - strlen(path));
 
-       delete_tasks = fopen(path, "r");
+       delete_tasks = fopen(path, "re");
        if (delete_tasks) {
                ret = cg_move_task_files(delete_tasks, target_tasks);
                fclose(delete_tasks);
@@ -1800,7 +1800,7 @@ int cgroup_delete_cgroup_ext(struct cgroup *cgroup, int flags)
                strncat(parent_path, "/tasks", sizeof(parent_path)
                                - strlen(parent_path));
 
-               parent_tasks = fopen(parent_path, "w");
+               parent_tasks = fopen(parent_path, "we");
                if (!parent_tasks) {
                        last_errno = errno;
                        ret = ECGOTHER;
@@ -1857,7 +1857,7 @@ static int cg_rd_ctrl_file(const char *subsys, const char *cgroup,
                return ECGFAIL;
 
        strncat(path, file, sizeof(path) - strlen(path));
-       ctrl_file = fopen(path, "r");
+       ctrl_file = fopen(path, "re");
        if (!ctrl_file)
                return ECGROUPVALUENOTEXIST;
 
@@ -2528,7 +2528,7 @@ int cgroup_get_current_controller_path(pid_t pid, const char *controller,
        }
 
        ret = ECGROUPNOTEXIST;
-       pid_cgroup_fd = fopen(path, "r");
+       pid_cgroup_fd = fopen(path, "re");
        if (!pid_cgroup_fd)
                goto cleanup_path;
 
@@ -2859,7 +2859,7 @@ int cgroup_read_stats_begin(const char *controller, const char *path,
 
        sprintf(stat_file, "%s/%s.stat", stat_file, controller);
 
-       fp = fopen(stat_file, "r");
+       fp = fopen(stat_file, "re");
        if (!fp) {
                cgroup_dbg("fopen failed\n");
                return ECGINVAL;
@@ -2926,7 +2926,7 @@ int cgroup_get_task_begin(const char *cgroup, const char *controller,
                return ECGOTHER;
        }
 
-       *handle = (void *) fopen(fullpath, "r");
+       *handle = (void *) fopen(fullpath, "re");
        free(fullpath);
 
        if (!*handle) {
@@ -3030,7 +3030,7 @@ int cgroup_get_uid_gid_from_procfs(pid_t pid, uid_t *euid, gid_t *egid)
        bool found_egid = false;
 
        sprintf(path, "/proc/%d/status", pid);
-       f = fopen(path, "r");
+       f = fopen(path, "re");
        if (!f)
                return ECGROUPNOTEXIST;
 
@@ -3081,7 +3081,7 @@ static int cg_get_procname_from_proc_status(pid_t pid, char **procname_status)
        char buf[4092];
 
        sprintf(path, "/proc/%d/status", pid);
-       f = fopen(path, "r");
+       f = fopen(path, "re");
        if (!f)
                return ECGROUPNOTEXIST;
 
@@ -3132,7 +3132,7 @@ static int cg_get_procname_from_proc_cmdline(pid_t pid,
                return ECGROUPNOTEXIST;
 
        sprintf(path, "/proc/%d/cmdline", pid);
-       f = fopen(path, "r");
+       f = fopen(path, "re");
        if (!f)
                return ECGROUPNOTEXIST;
 
@@ -3372,7 +3372,7 @@ int cgroup_get_all_controller_begin(void **handle, struct controller_data *info)
        if (!info)
                return ECGINVAL;
 
-       proc_cgroup = fopen("/proc/cgroups", "r");
+       proc_cgroup = fopen("/proc/cgroups", "re");
        if (!proc_cgroup) {
                last_errno = errno;
                return ECGOTHER;

diff --git a/src/config.c b/src/config.c
index e0d23fc7077ef0e1e25409fb628bda503ac7bc4d..a29649a92d29954ae2fa937a1def785323a4772d 100644 (file)
--- a/src/config.c
+++ b/src/config.c
@@ -674,7 +674,7 @@ int cgroup_config_load_config(const char *pathname)
        int error;
        int namespace_enabled = 0;
        int mount_enabled = 0;
-       yyin = fopen(pathname, "r");
+       yyin = fopen(pathname, "re");
 
        if (!yyin) {
                cgroup_dbg("Failed to open file %s\n", pathname);