Re: [PATCH] openat2: reject RESOLVE_BENEATH|RESOLVE_IN_ROOT

[Christian Brauner]

On Wed, Oct 07, 2020 at 09:36:08PM +1100, Aleksa Sarai wrote:
> This was an oversight in the original implementation, as it makes no
> sense to specify both scoping flags to the same openat2(2) invocation
> (before this patch, the result of such an invocation was equivalent to
> RESOLVE_IN_ROOT being ignored).
> 
> This is a userspace-visible ABI change, but the only user of openat2(2)
> at the moment is LXC which doesn't specify both flags and so no
> userspace programs will break as a result.

Indeed!

> 
> Fixes: fddb5d430ad9 ("open: introduce openat2(2) syscall")
> Signed-off-by: Aleksa Sarai <cyphar@xxxxxxxxxx>
> Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx> # v5.6+
> ---

Thanks! This is a good fix imho.
Christian