Comment 6 for bug 1873627

Thanks for the strace, these looked like the 'important' parts:

sendto(3, {{len=56, type=AUDIT_SET, flags=NLM_F_REQUEST|NLM_F_ACK, seq=3, pid=0}, "\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa2\xb8\x29\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"...}, 56, 0, {sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, 12) = 56
poll([{fd=3, events=POLLIN}], 1, 500) = 1 ([{fd=3, revents=POLLIN}])
recvfrom(3, {{len=76, type=NLMSG_ERROR, flags=0, seq=3, pid=2734242}, {error=-EEXIST, msg={{len=56, type=AUDIT_SET, flags=NLM_F_REQUEST|NLM_F_ACK, seq=3, pid=0}, "\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa2\xb8\x29\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"...}}}, 8988, MSG_PEEK|MSG_DONTWAIT, {sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, [12]) = 76
recvfrom(3, {{len=76, type=NLMSG_ERROR, flags=0, seq=3, pid=2734242}, {error=-EEXIST, msg={{len=56, type=AUDIT_SET, flags=NLM_F_REQUEST|NLM_F_ACK, seq=3, pid=0}, "\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa2\xb8\x29\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"...}}}, 8988, MSG_DONTWAIT, {sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, [12]) = 76
write(2, "Error setting audit daemon pid ("..., 44Error setting audit daemon pid (File exists)) = 44

...

write(2, "The audit daemon is exiting.", 28The audit daemon is exiting.) = 28
write(2, "\n", 1
) = 1
sendto(3, {{len=56, type=AUDIT_SET, flags=NLM_F_REQUEST|NLM_F_ACK, seq=4, pid=0}, "\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"...}, 56, 0, {sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, 12) = 56
poll([{fd=3, events=POLLIN}], 1, 500) = 1 ([{fd=3, revents=POLLIN}])
recvfrom(3, {{len=76, type=NLMSG_ERROR, flags=0, seq=4, pid=2734242}, {error=-EACCES, msg={{len=56, type=AUDIT_SET, flags=NLM_F_REQUEST|NLM_F_ACK, seq=4, pid=0}, "\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"...}}}, 8988, MSG_PEEK|MSG_DONTWAIT, {sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, [12]) = 76
recvfrom(3, {{len=76, type=NLMSG_ERROR, flags=0, seq=4, pid=2734242}, {error=-EACCES, msg={{len=56, type=AUDIT_SET, flags=NLM_F_REQUEST|NLM_F_ACK, seq=4, pid=0}, "\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"...}}}, 8988, MSG_DONTWAIT, {sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, [12]) = 76
write(2, "Error setting audit daemon pid ("..., 50Error setting audit daemon pid (Permission denied)) = 50
write(2, "\n", 1
) = 1

I don't understand why it's issuing an AUDIT_SET command after it already decided to exit -- maybe it's just trying to tear itself down cleanly.

I found a few cases in the kernel code for returning both file exists and permission denied:

kernel/audit.c audit_netlink_ok():

                /* Only support auditd and auditctl in initial pid namespace
                 * for now. */
                if (task_active_pid_ns(current) != &init_pid_ns)
                        return -EPERM;

                if (!netlink_capable(skb, CAP_AUDIT_CONTROL))
                        err = -EPERM;
                break;

kernel/audit.c audit_receive_msg():

                        auditd_pid = auditd_pid_vnr();
                        if (auditd_pid) {
                                /* replacing a healthy auditd is not allowed */
                                if (new_pid) {
                                        audit_log_config_change("audit_pid",
                                                        new_pid, auditd_pid, 0);
                                        return -EEXIST;
                                }

kernel/audit.c audit_set_feature():

               /* are we changing a locked feature? */
                if (old_lock && (new_feature != old_feature)) {
                        audit_log_feature_change(i, old_feature, new_feature,
                                                 old_lock, new_lock, 0);
                        return -EPERM;
                }

Do any of these feel applicable to your environment?

Thanks