Re: [RFC PATCH] audit: Send netlink ACK before setting connection in auditd_set

[Paul Moore]

On Fri, Sep 22, 2023 at 11:28 AM Chris Riches <chris.riches@xxxxxxxxxxx> wrote:
>
> When auditd_set sets the auditd_conn pointer, audit messages can
> immediately be put on the socket by other kernel threads. If the backlog
> is large or the rate is high, this can immediately fill the socket
> buffer. If the audit daemon requested an ACK for this operation, a full
> socket buffer causes the ACK to get dropped, also setting ENOBUFS on the
> socket.
>
> To avoid this race and ensure ACKs get through, fast-track the ACK in
> this specific case to ensure it is sent before auditd_conn is set.
>
> Signed-off-by: Chris Riches <chris.riches@xxxxxxxxxxx>
>
> ---
>
> This mail is more of an RFC than a patch, though the included patch is a
> useful illustation and might even be suitable for inclusion ...

Hi Chris,

Thanks for the patch and the background information, that's always
helpful.  Unfortunately I have limited network access at the moment,
but I'll put this on my list to look at next week.

-- 
paul-moore.com