Re: [PATCH 4.14] inet: use bigger hash table for IP ID generation (backported to 4.14)

[Amit Klein]

I believe you ask about this one:
[ Upstream commit aa6dd211e4b1dde9d5dc25d699d35f789ae7eeba ]



On Fri, Jun 18, 2021 at 1:24 PM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Fri, Jun 18, 2021 at 02:51:22AM -0700, Amit Klein wrote:
> > Subject: inet: use bigger hash table for IP ID generation (backported to 4.14)
> > From: Amit Klein <aksecurity@xxxxxxxxx>
> >
> > This is a backport to 4.14 of the following patch, originally
> > developed by Eric Dumazet.
> >
> > In commit 73f156a6e8c1 ("inetpeer: get rid of ip_id_count")
> > I used a very small hash table that could be abused
> > by patient attackers to reveal sensitive information.
> >
> > Switch to a dynamic sizing, depending on RAM size.
> >
> > Typical big hosts will now use 128x more storage (2 MB)
> > to get a similar increase in security and reduction
> > of hash collisions.
> >
> > As a bonus, use of alloc_large_system_hash() spreads
> > allocated memory among all NUMA nodes.
> >
> > Fixes: 73f156a6e8c1 ("inetpeer: get rid of ip_id_count")
> > Reported-by: Amit Klein <aksecurity@xxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
> > Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
> > Cc: Willy Tarreau <w@xxxxxx>
> > ---
>
> What is the git commit id of this patch in Linus's tree?
>
> thanks,
>
> greg k-h