audit: do not complain if kernel lacks audit

When running on a kernel without audit support, systemd currently
writes a mysterious-sounding error to its log:

	systemd[1]: Failed to connect to audit log: Protocol not supported

Better to suppress the audit_open() failure message when (and only
when) it is due to running on a kernel without audit support, since in
this case the admin probably does not mind systemd not writing to the
audit log.  This way, more serious errors like ENOMEM and EACCES will
stand out more.

diff --git a/src/manager.c b/src/manager.c
index 6d20258..111167a 100644 (file)
--- a/src/manager.c
+++ b/src/manager.c
@@ -286,7 +286,10 @@ int manager_new(ManagerRunningAs running_as, Manager **_m) {
                 goto fail;
 
 #ifdef HAVE_AUDIT
-        if ((m->audit_fd = audit_open()) < 0)
+        if ((m->audit_fd = audit_open()) < 0 &&
+            /* If the kernel lacks netlink or audit support,
+             * don't worry about it. */
+            errno != EAFNOSUPPORT && errno != EPROTONOSUPPORT)
                 log_error("Failed to connect to audit log: %m");
 #endif
 

diff --git a/src/update-utmp.c b/src/update-utmp.c
index f81e7f4..12e4d11 100644 (file)
--- a/src/update-utmp.c
+++ b/src/update-utmp.c
@@ -376,7 +376,10 @@ int main(int argc, char *argv[]) {
         umask(0022);
 
 #ifdef HAVE_AUDIT
-        if ((c.audit_fd = audit_open()) < 0)
+        if ((c.audit_fd = audit_open()) < 0 &&
+            /* If the kernel lacks netlink or audit support,
+             * don't worry about it. */
+            errno != EAFNOSUPPORT && errno != EPROTONOSUPPORT)
                 log_error("Failed to connect to audit log: %m");
 #endif