Re: [PATCH v2 1/9] sysctl: fix lax sysctl_check_table() sanity check

[Kees Cook]

On Fri, Feb 10, 2017 at 4:36 PM, Luis R. Rodriguez <mcgrof@xxxxxxxxxx> wrote:
> Commit 7c60c48f58a7 ("sysctl: Improve the sysctl sanity checks")
> improved sanity checks considerbly, however the enhancements on
> sysctl_check_table() meant adding a functional change so that
> only the last table entry's sanity error is propagated. It also
> changed the way errors were propagated so that each new check
> reset the err value, this means only last sanity check computed
> is used for an error. This has been in the kernel since v3.4 days.
>
> Fix this by carrying on errors from previous checks and iterations
> as we traverse the table and ensuring we keep any error from previous
> checks. We keep iterating on the table even if an error is found so
> we can complain for all errors found in one shot. This works as
> -EINVAL is always returned on error anyway, and the check for error
> is any non-zero value.

I assume this didn't catch anything that was broken-but-hidden in the kernel?

>
> Fixes: 7c60c48f58a7 ("sysctl: Improve the sysctl sanity checks")
> Signed-off-by: Luis R. Rodriguez <mcgrof@xxxxxxxxxx>

Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>

-Kees

-- 
Kees Cook
Pixel Security