# Re: \[PATCH\] lockdown: ratelimit denial messages

- From: Paul Moore \<paul@paul-moore.com\>
- Date: 2022-09-14 11:43:44 
- List: linux-security-module
- Page: https://ratatoskr.run/linux-security-module/2022/09/1933354
- Thread: https://ratatoskr.run/linux-security-module/2022/09/1927350/t.md

```text
On Fri, Sep 9, 2022 at 10:05 AM Paul Moore [ref] wrote:
> On Thu, Sep 8, 2022 at 6:02 PM Nathan Lynch [ref] wrote:
> >
> > User space can flood the log with lockdown denial messages:
> >
> > [  662.555584] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
> > [  662.563237] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
> > [  662.571134] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
> > [  662.578668] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
> > [  662.586021] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
> > [  662.593398] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
> >
> > Ratelimiting these shouldn't meaningfully degrade the quality of the
> > information logged.
> >
> > Signed-off-by: Nathan Lynch <redacted>
> > ---
> >  security/lockdown/lockdown.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
>
> This seems reasonable.  While the last visible lockdown message to the
> console might be incorrect/old, I think it would give the user a good
> indication that lockdown is being hit and hopefully preserve the start
> of the denial storm.  It is also worth noting that this does introduce
> a spinlock to this code path, but since it is only an issue on error I
> doubt it will have any significant impact.
>
> I'll leave this until next week to give people a chance to
> comment/object, but if there are no further comments I'll plan on
> merging this into lsm/next.

Now merged into lsm/next, thanks!

-- 
paul-moore.com
```