Re: [PATCH] x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task

[Eric Dumazet]

On Sat, Aug 15, 2020 at 4:48 AM Ingo Molnar <mingo@xxxxxxxxxx> wrote:
>
>
> * Eric Dumazet <edumazet@xxxxxxxxxx> wrote:
>
> > syzbot found its way in 86_fsgsbase_read_task() [1]
> >
> > Fix is to make sure ldt pointer is not NULL.
>
> Thanks for this fix. Linus has picked it up (inclusive the typos to
> the x86_fsgsbase_read_task() function name ;-), it's now upstream
> under:
>
>   8ab49526b53d: ("x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task")
>
> By the fixes tag it looks like this should probably be backported all
> the way back to ~v4.20 or so?

This is absolutely right, sorry about the lack of a stable tag.

Most of my patches usually land into David Miller trees, where the
stable tag is not welcomed.
We use  Fixes: tags to convey the exact information needed for stable backports.

Thanks.