From: Mike Yuan <me@yhndnzj.com>
Date: Fri, 19 Jan 2024 12:00:31 +0000 (+0800)
Subject: pam_systemd: always check if session is busy
X-Git-Tag: v256-rc1~1099^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F31012%2Fhead;p=thirdparty%2Fsystemd.git

pam_systemd: always check if session is busy

We need to check for BUS_ERROR_SESSION_BUSY no matter
whether pidfd is used, i.e. after we retry with
CreateSession().
---

diff --git a/src/login/pam_systemd.c b/src/login/pam_systemd.c
index b8313b92ccc..db623a3eaa1 100644
--- a/src/login/pam_systemd.c
+++ b/src/login/pam_systemd.c
@@ -1080,33 +1080,33 @@ _public_ PAM_EXTERN int pam_sm_open_session(
                 return pam_bus_log_create_error(handle, r);
 
         r = sd_bus_call(bus, m, LOGIN_SLOW_BUS_CALL_TIMEOUT_USEC, &error, &reply);
+        if (r < 0 && sd_bus_error_has_name(&error, SD_BUS_ERROR_UNKNOWN_METHOD)) {
+                sd_bus_error_free(&error);
+                pam_debug_syslog(handle, debug,
+                                 "CreateSessionWithPIDFD() API is not available, retrying with CreateSession().");
+
+                m = sd_bus_message_unref(m);
+                r = create_session_message(bus,
+                                           handle,
+                                           &context,
+                                           /* avoid_pidfd = */ true,
+                                           &m);
+                if (r < 0)
+                        return pam_bus_log_create_error(handle, r);
+
+                r = sd_bus_call(bus, m, LOGIN_SLOW_BUS_CALL_TIMEOUT_USEC, &error, &reply);
+        }
         if (r < 0) {
                 if (sd_bus_error_has_name(&error, BUS_ERROR_SESSION_BUSY)) {
+                        /* We are already in a session, don't do anything */
                         pam_debug_syslog(handle, debug,
                                          "Not creating session: %s", bus_error_message(&error, r));
-                        /* We are already in a session, don't do anything */
                         goto success;
-                } else if (sd_bus_error_has_name(&error, SD_BUS_ERROR_UNKNOWN_METHOD)) {
-                        pam_debug_syslog(handle, debug,
-                                         "CreateSessionWithPIDFD() API is not available, retrying with CreateSession().");
-
-                        m = sd_bus_message_unref(m);
-                        r = create_session_message(bus,
-                                                   handle,
-                                                   &context,
-                                                   true /* avoid_pidfd = */,
-                                                   &m);
-                        if (r < 0)
-                                return pam_bus_log_create_error(handle, r);
-
-                        sd_bus_error_free(&error);
-                        r = sd_bus_call(bus, m, LOGIN_SLOW_BUS_CALL_TIMEOUT_USEC, &error, &reply);
-                }
-                if (r < 0) {
-                        pam_syslog(handle, LOG_ERR,
-                                   "Failed to create session: %s", bus_error_message(&error, r));
-                        return PAM_SESSION_ERR;
                 }
+
+                pam_syslog(handle, LOG_ERR,
+                           "Failed to create session: %s", bus_error_message(&error, r));
+                return PAM_SESSION_ERR;
         }
 
         r = sd_bus_message_read(reply,