pam_systemd: use F_DUPFD_CLOEXEC when dupping session fds

[elogind.git] / src / login / pam-module.c

diff --git a/src/login/pam-module.c b/src/login/pam-module.c
index 3b2966b30cf833fa37d78f13922c19ee3cedeb8c..1259457efc5f43351a6cf2f826e8a228cdeb91cf 100644 (file)
--- a/src/login/pam-module.c
+++ b/src/login/pam-module.c
@@ -234,7 +234,7 @@ _public_ PAM_EXTERN int pam_sm_open_session(
                 return PAM_SESSION_ERR;
 
         if (debug)
-                pam_syslog(handle, LOG_INFO, "pam-systemd initializing");
+                pam_syslog(handle, LOG_DEBUG, "pam-systemd initializing");
 
         r = get_user_data(handle, &username, &pw);
         if (r != PAM_SUCCESS) {
@@ -374,7 +374,7 @@ _public_ PAM_EXTERN int pam_sm_open_session(
                            "uid=%u pid=%u service=%s type=%s class=%s desktop=%s seat=%s vtnr=%u tty=%s display=%s remote=%s remote_user=%s remote_host=%s",
                            pw->pw_uid, getpid(),
                            strempty(service),
-                           type, class, desktop,
+                           type, class, strempty(desktop),
                            strempty(seat), vtnr, strempty(tty), strempty(display),
                            yes_no(remote), strempty(remote_user), strempty(remote_host));
 
@@ -475,7 +475,7 @@ _public_ PAM_EXTERN int pam_sm_open_session(
         }
 
         if (session_fd >= 0) {
-                session_fd = dup(session_fd);
+                session_fd = fcntl(session_fd, F_DUPFD_CLOEXEC, 3);
                 if (session_fd < 0) {
                         pam_syslog(handle, LOG_ERR, "Failed to dup session fd: %m");
                         return PAM_SESSION_ERR;
@@ -484,7 +484,7 @@ _public_ PAM_EXTERN int pam_sm_open_session(
                 r = pam_set_data(handle, "systemd.session-fd", INT_TO_PTR(session_fd+1), NULL);
                 if (r != PAM_SUCCESS) {
                         pam_syslog(handle, LOG_ERR, "Failed to install session fd.");
-                        close_nointr_nofail(session_fd);
+                        safe_close(session_fd);
                         return r;
                 }
         }
@@ -499,7 +499,7 @@ _public_ PAM_EXTERN int pam_sm_close_session(
 
         _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_bus_unref_ sd_bus *bus = NULL;
-        const void *p = NULL, *existing = NULL;
+        const void *existing = NULL;
         const char *id;
         int r;
 
@@ -519,10 +519,8 @@ _public_ PAM_EXTERN int pam_sm_close_session(
 
                 r = sd_bus_open_system(&bus);
                 if (r < 0) {
-                        pam_syslog(handle, LOG_ERR,
-                                  "Failed to connect to system bus: %s", strerror(-r));
-                        r = PAM_SESSION_ERR;
-                        goto finish;
+                        pam_syslog(handle, LOG_ERR, "Failed to connect to system bus: %s", strerror(-r));
+                        return PAM_SESSION_ERR;
                 }
 
                 r = sd_bus_call_method(bus,
@@ -535,20 +533,16 @@ _public_ PAM_EXTERN int pam_sm_close_session(
                                        "s",
                                        id);
                 if (r < 0) {
-                        pam_syslog(handle, LOG_ERR,
-                                   "Failed to release session: %s", bus_error_message(&error, r));
-
-                        r = PAM_SESSION_ERR;
-                        goto finish;
+                        pam_syslog(handle, LOG_ERR, "Failed to release session: %s", bus_error_message(&error, r));
+                        return PAM_SESSION_ERR;
                 }
         }
 
-        r = PAM_SUCCESS;
+        /* Note that we are knowingly leaking the FIFO fd here. This
+         * way, logind can watch us die. If we closed it here it would
+         * not have any clue when that is completed. Given that one
+         * cannot really have multiple PAM sessions open from the same
+         * process this means we will leak one FD at max. */
 
-finish:
-        pam_get_data(handle, "systemd.session-fd", &p);
-        if (p)
-                close_nointr(PTR_TO_INT(p) - 1);
-
-        return r;
+        return PAM_SUCCESS;
 }