return ret;
}
+/*
+ * Return 1 if the given path is readable by the current UID or 0 if not.
+ * Return -1 if the path is EPERM.
+ */
+static int validate_file_read_creds(const char *path)
+{
+ int ret;
+
+ assert(path);
+
+ /* Can we read the file. */
+ ret = access(path, R_OK);
+ if (!ret) {
+ goto valid;
+ }
+ if (errno == EACCES) {
+ return -1;
+ } else {
+ /* Invalid. */
+ return 0;
+ }
+valid:
+ return 1;
+}
+
static
int load_session_from_file(const char *path, const char *session_name,
struct session_config_validation_ctx *validation_ctx, int override)
xmlDocPtr doc = NULL;
xmlNodePtr sessions_node;
xmlNodePtr session_node;
- struct stat sb;
assert(path);
assert(validation_ctx);
- ret = stat(path, &sb);
- if (ret) {
- ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
+ ret = validate_file_read_creds(path);
+ if (ret != 1) {
+ if (ret == -1) {
+ ret = -LTTNG_ERR_EPERM;
+ } else {
+ ret = -LTTNG_ERR_LOAD_SESSION_NOENT;
+ }
goto end;
}
/*
* Validate that the given path's credentials and the current process have the
- * same UID. If so, return 0 else return 1 if it does NOT match.
+ * same UID. If so, return 1 else return 0 if it does NOT match.
*/
static int validate_path_creds(const char *path)
{
assert(path);
- if (uid != 0) {
+ if (uid == 0) {
goto valid;
}
}
valid:
- return 0;
-invalid:
return 1;
+invalid:
+ return 0;
}
LTTNG_HIDDEN
int override, unsigned int autoload)
{
int ret;
+ const char *path_ptr = NULL;
struct session_config_validation_ctx validation_ctx = { 0 };
ret = init_session_config_validation_ctx(&validation_ctx);
char *home_path;
const char *sys_path;
- /*
- * Try system session configuration path. Ignore error here so we can
- * continue loading the home sessions. The above call should print an
- * error to inform the user.
- */
- if (autoload) {
- sys_path = DEFAULT_SESSION_SYSTEM_CONFIGPATH "/"
- DEFAULT_SESSION_CONFIG_AUTOLOAD;
- } else {
- sys_path = DEFAULT_SESSION_HOME_CONFIGPATH;
- }
-
- ret = validate_path_creds(sys_path);
- if (!ret && autoload) {
- (void) load_session_from_path(sys_path, session_name,
- &validation_ctx, override);
- }
-
/* Try home path */
home_path = utils_get_home_dir();
if (home_path) {
char path[PATH_MAX];
+ /*
+ * Try user session configuration path. Ignore error here so we can
+ * continue loading the system wide sessions.
+ */
if (autoload) {
ret = snprintf(path, sizeof(path),
DEFAULT_SESSION_HOME_CONFIGPATH "/"
DEFAULT_SESSION_CONFIG_AUTOLOAD, home_path);
+ if (ret < 0) {
+ PERROR("snprintf session autoload home config path");
+ goto end;
+ }
+
+ /*
+ * Credentials are only validated for the autoload in order to
+ * avoid any user session daemon to try to load kernel sessions
+ * automatically and failing all the times.
+ */
+ ret = validate_path_creds(path);
+ if (ret) {
+ path_ptr = path;
+ }
} else {
ret = snprintf(path, sizeof(path),
DEFAULT_SESSION_HOME_CONFIGPATH, home_path);
+ if (ret < 0) {
+ PERROR("snprintf session home config path");
+ goto end;
+ }
+ path_ptr = path;
}
- if (ret < 0) {
- goto end;
+ if (path_ptr) {
+ ret = load_session_from_path(path_ptr, session_name,
+ &validation_ctx, override);
+ if (ret && ret != -LTTNG_ERR_LOAD_SESSION_NOENT) {
+ goto end;
+ }
+ /*
+ * Continue even if the session was found since we have to try
+ * the system wide sessions.
+ */
}
+ }
- ret = validate_path_creds(path);
- if (ret && autoload) {
- ret = 0;
- goto end;
- }
+ /* Reset path pointer for the system wide dir. */
+ path_ptr = NULL;
- ret = load_session_from_path(path, session_name,
- &validation_ctx, override);
- if (!ret || (ret && ret != -LTTNG_ERR_LOAD_SESSION_NOENT)) {
- /* Session found or an error occured */
- goto end;
+ /* Try system wide configuration directory. */
+ if (autoload) {
+ sys_path = DEFAULT_SESSION_SYSTEM_CONFIGPATH "/"
+ DEFAULT_SESSION_CONFIG_AUTOLOAD;
+ ret = validate_path_creds(sys_path);
+ if (ret) {
+ path_ptr = sys_path;
}
+ } else {
+ sys_path = DEFAULT_SESSION_SYSTEM_CONFIGPATH;
+ path_ptr = sys_path;
+ }
+
+ if (path_ptr) {
+ ret = load_session_from_path(path_ptr, session_name,
+ &validation_ctx, override);
}
} else {
ret = access(path, F_OK);