X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flogin%2Fpam_elogind.c;h=f66f1ce8428bfcfc6ee135dd940e330e4cd62ae1;hp=f75b8ac2c91aece4029ae3e0cfee83c22cead8fd;hb=c73bfb05cb09992935ede3247a1cc4726e54a44d;hpb=b767c85a403ee56b5f87bc9414638b857dabd18d

diff --git a/src/login/pam_elogind.c b/src/login/pam_elogind.c
index f75b8ac2c..f66f1ce84 100644
--- a/src/login/pam_elogind.c
+++ b/src/login/pam_elogind.c
@@ -31,6 +31,7 @@
 #include <security/pam_ext.h>
 #include <security/pam_misc.h>
 
+#include "bus-common-errors.h"
 #include "util.h"
 #include "audit.h"
 #include "macro.h"
@@ -178,24 +179,37 @@ static int export_legacy_dbus_address(
                 const char *runtime) {
 
         _cleanup_free_ char *s = NULL;
-        int r;
-
-        /* skip export if kdbus is not active */
-        if (!is_kdbus_available())
-                return PAM_SUCCESS;
-
-        if (asprintf(&s, KERNEL_USER_BUS_ADDRESS_FMT ";" UNIX_USER_BUS_ADDRESS_FMT, uid, runtime) < 0) {
-                pam_syslog(handle, LOG_ERR, "Failed to set bus variable.");
-                return PAM_BUF_ERR;
+        int r = PAM_BUF_ERR;
+
+        if (is_kdbus_available()) {
+                if (asprintf(&s, KERNEL_USER_BUS_ADDRESS_FMT ";" UNIX_USER_BUS_ADDRESS_FMT, uid, runtime) < 0)
+                        goto error;
+        } else {
+                /* FIXME: We *really* should move the access() check into the
+                 * daemons that spawn dbus-daemon, instead of forcing
+                 * DBUS_SESSION_BUS_ADDRESS= here. */
+
+                s = strjoin(runtime, "/bus", NULL);
+                if (!s)
+                        goto error;
+
+                if (access(s, F_OK) < 0)
+                        return PAM_SUCCESS;
+
+                s = mfree(s);
+                if (asprintf(&s, UNIX_USER_BUS_ADDRESS_FMT, runtime) < 0)
+                        goto error;
         }
 
         r = pam_misc_setenv(handle, "DBUS_SESSION_BUS_ADDRESS", s, 0);
-        if (r != PAM_SUCCESS) {
-                pam_syslog(handle, LOG_ERR, "Failed to set bus variable.");
-                return r;
-        }
+        if (r != PAM_SUCCESS)
+                goto error;
 
         return PAM_SUCCESS;
+
+error:
+        pam_syslog(handle, LOG_ERR, "Failed to set bus variable.");
+        return r;
 }
 
 _public_ PAM_EXTERN int pam_sm_open_session(
@@ -243,7 +257,7 @@ _public_ PAM_EXTERN int pam_sm_open_session(
         }
 
         /* Make sure we don't enter a loop by talking to
-         * logind when it is actually waiting for the
+         * systemd-logind when it is actually waiting for the
          * background to finish start-up. If the service is
          * "systemd-user" we simply set XDG_RUNTIME_DIR and
          * leave. */
@@ -399,8 +413,13 @@ _public_ PAM_EXTERN int pam_sm_open_session(
                                remote_host,
                                0);
         if (r < 0) {
-                pam_syslog(handle, LOG_ERR, "Failed to create session: %s", bus_error_message(&error, r));
-                return PAM_SYSTEM_ERR;
+                if (sd_bus_error_has_name(&error, BUS_ERROR_SESSION_BUSY)) {
+                        pam_syslog(handle, LOG_DEBUG, "Cannot create session: %s", bus_error_message(&error, r));
+                        return PAM_SUCCESS;
+                } else {
+                        pam_syslog(handle, LOG_ERR, "Failed to create session: %s", bus_error_message(&error, r));
+                        return PAM_SYSTEM_ERR;
+                }
         }
 
         r = sd_bus_message_read(reply,