Re: [RFC PATCH v3] audit: use proper refcount locking on audit_sock
On 2016-12-13 16:19, Cong Wang wrote:
On Tue, Dec 13, 2016 at 7:03 AM, Richard Guy Briggs
<rgb(a)redhat.com> wrote:
> @@ -1283,8 +1299,10 @@ static void __net_exit audit_net_exit(struct net *net)
> {
> struct audit_net *aunet = net_generic(net, audit_net_id);
> struct sock *sock = aunet->nlsk;
> + mutex_lock(&audit_cmd_mutex);
> if (sock == audit_sock)
> auditd_reset();
> + mutex_unlock(&audit_cmd_mutex);
This still doesn't look correct to me, b/c here we release the audit_sock
refcnt twice:
1) inside audit_reset()
The audit_reset() refcount decrement corresponds to a setting of
audit_sock only if audit_sock is still non-NULL.
2) netlink_kernel_release()
This refcount decrement corresponds to netlink_kernel_create().
- RGB
--
Richard Guy Briggs <rgb(a)redhat.com>
Kernel Security Engineering, Base Operating Systems, Red Hat
Remote, Ottawa, Canada
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