Re: [PATCH] Audit: netlink socket can be auto-bound to pid other than current->pid

Eric Paris wrote: > On 3/18/08, Pavel Emelyanov <xemul(a)openvz.org&gt; wrote: > > Can we please just leave audit_pid as the one flag to tell us if > auditd is supposedly up there in userspace? Use audit_nlk_pid to send > messages to the right place, but leave everything else to do with > audit_pid alone. OK, point taken ;) Is that patch looks OK? If yes, I'll comment it properly and re-send to Andrew. The audit_nlk_pid reset to 0 is not required, since all the decisions are taken based on audit_pid value only.

Signed-off-by: Pavel Emelyanov <xemul(a)openvz.org&gt; diff --git a/kernel/audit.c b/kernel/audit.c index ccc7d0e..12a0278 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -77,9 +77,13 @@ static int audit_default; /* If auditing cannot proceed, audit_failure selects what happens. */ static int audit_failure = AUDIT_FAIL_PRINTK; -/* If audit records are to be written to the netlink socket, audit_pid - * contains the (non-zero) pid. */ +/* + * If audit records are to be written to the netlink socket, audit_pid + * contains the pid of the auditd process and audit_nlk_pid contains + * the pid to use to send netlink messages to that process. + */ int audit_pid; +static int audit_nlk_pid; /* If audit_rate_limit is non-zero, limit the rate of sending audit records * to that number per second. This prevents DoS attacks, but results in @@ -349,7 +353,7 @@ static int kauditd_thread(void *dummy) wake_up(&audit_backlog_wait); if (skb) { if (audit_pid) { - int err = netlink_unicast(audit_sock, skb, audit_pid, 0); + int err = netlink_unicast(audit_sock, skb, audit_nlk_pid, 0); if (err < 0) { BUG_ON(err != -ECONNREFUSED); /* Shoudn't happen */ printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid); @@ -626,6 +630,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) sid, 1); audit_pid = new_pid; + audit_nlk_pid = NETLINK_CB(skb).pid; } if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) err = audit_set_rate_limit(status_get->rate_limit,