New upstream version 241upstream/241

1 files changed, 51 insertions, 5 deletions

diff --git a/src/login/pam_systemd.c b/src/login/pam_systemd.c
index c7d9dcf4e2..997b74eb88 100644
--- a/src/login/pam_systemd.c
+++ b/src/login/pam_systemd.c
@@ -28,6 +28,7 @@
 #include "path-util.h"
 #include "process-util.h"
 #include "socket-util.h"
+#include "stdio-util.h"
 #include "strv.h"
 #include "terminal-util.h"
 #include "util.h"
@@ -190,6 +191,45 @@ static int get_seat_from_display(const char *display, const char **seat, uint32_
         return 0;
 }
 
+static int export_legacy_dbus_address(
+                pam_handle_t *handle,
+                uid_t uid,
+                const char *runtime) {
+
+        const char *s;
+        _cleanup_free_ char *t = NULL;
+        int r = PAM_BUF_ERR;
+
+        /* We need to export $DBUS_SESSION_BUS_ADDRESS because various applications will not connect
+         * correctly to the bus without it. This setting matches what dbus.socket does for the user
+         * session using 'systemctl --user set-environment'. We want to have the same configuration
+         * in processes started from the PAM session.
+         *
+         * The setting of the address is guarded by the access() check because it is also possible to compile
+         * dbus without --enable-user-session, in which case this socket is not used, and
+         * $DBUS_SESSION_BUS_ADDRESS should not be set. An alternative approach would to not do the access()
+         * check here, and let applications try on their own, by using "unix:path=%s/bus;autolaunch:". But we
+         * expect the socket to be present by the time we do this check, so we can just as well check once
+         * here. */
+
+        s = strjoina(runtime, "/bus");
+        if (access(s, F_OK) < 0)
+                return PAM_SUCCESS;
+
+        if (asprintf(&t, DEFAULT_USER_BUS_ADDRESS_FMT, runtime) < 0)
+                goto error;
+
+        r = pam_misc_setenv(handle, "DBUS_SESSION_BUS_ADDRESS", t, 0);
+        if (r != PAM_SUCCESS)
+                goto error;
+
+        return PAM_SUCCESS;
+
+error:
+        pam_syslog(handle, LOG_ERR, "Failed to set bus variable.");
+        return r;
+}
+
 static int append_session_memory_max(pam_handle_t *handle, sd_bus_message *m, const char *limit) {
         uint64_t val;
         int r;
@@ -392,11 +432,9 @@ _public_ PAM_EXTERN int pam_sm_open_session(
 
         pam_get_item(handle, PAM_SERVICE, (const void**) &service);
         if (streq_ptr(service, "systemd-user")) {
-                _cleanup_free_ char *rt = NULL;
-
-                if (asprintf(&rt, "/run/user/"UID_FMT, pw->pw_uid) < 0)
-                        return PAM_BUF_ERR;
+                char rt[STRLEN("/run/user/") + DECIMAL_STR_MAX(uid_t)];
 
+                xsprintf(rt, "/run/user/"UID_FMT, pw->pw_uid);
                 if (validate_runtime_directory(handle, rt, pw->pw_uid)) {
                         r = pam_misc_setenv(handle, "XDG_RUNTIME_DIR", rt, 0);
                         if (r != PAM_SUCCESS) {
@@ -405,6 +443,10 @@ _public_ PAM_EXTERN int pam_sm_open_session(
                         }
                 }
 
+                r = export_legacy_dbus_address(handle, pw->pw_uid, rt);
+                if (r != PAM_SUCCESS)
+                        return r;
+
                 return PAM_SUCCESS;
         }
 
@@ -569,7 +611,7 @@ _public_ PAM_EXTERN int pam_sm_open_session(
         if (r < 0) {
                 if (sd_bus_error_has_name(&error, BUS_ERROR_SESSION_BUSY)) {
                         if (debug)
-                                pam_syslog(handle, LOG_DEBUG, "Cannot create session: %s", bus_error_message(&error, r));
+                                pam_syslog(handle, LOG_DEBUG, "Not creating 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));
@@ -613,6 +655,10 @@ _public_ PAM_EXTERN int pam_sm_open_session(
                         if (r != PAM_SUCCESS)
                                 return r;
                 }
+
+                r = export_legacy_dbus_address(handle, pw->pw_uid, runtime_path);
+                if (r != PAM_SUCCESS)
+                        return r;
         }
 
         /* Most likely we got the session/type/class from environment variables, but might have gotten the data