netdev - Re: [PATCH net-next 1/3] ipv6: sr: Fix MAC comparison to be constant-time

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20250818203022.GA1305@sol>
Date: Mon, 18 Aug 2025 13:30:22 -0700
From: Eric Biggers <ebiggers@...nel.org>
To: Andrea Mayer <andrea.mayer@...roma2.it>
Cc: netdev@...r.kernel.org, David Lebrun <dlebrun@...gle.com>,
	stable@...r.kernel.org, stefano.salsano@...roma2.it,
	Paolo Lungaroni <paolo.lungaroni@...roma2.it>
Subject: Re: [PATCH net-next 1/3] ipv6: sr: Fix MAC comparison to be
 constant-time

On Mon, Aug 18, 2025 at 07:38:52PM +0000, Eric Biggers wrote:
> On Mon, Aug 18, 2025 at 09:16:07PM +0200, Andrea Mayer wrote:
> > On Fri, 15 Aug 2025 20:11:34 -0700
> > Eric Biggers <ebiggers@...nel.org> wrote:
> > 
> > > To prevent timing attacks, MACs need to be compared in constant time.
> > > Use the appropriate helper function for this.
> > > 
> > > Fixes: bf355b8d2c30 ("ipv6: sr: add core files for SR HMAC support")
> > > Cc: stable@...r.kernel.org
> > > Signed-off-by: Eric Biggers <ebiggers@...nel.org>
> > > ---
> > >  net/ipv6/seg6_hmac.c | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > > 
> > 
> > Hi Eric,
> > 
> > Thanks for the fix!
> > 
> > I believe it would be best to submit this fix separately from the current patch
> > set. Since this addresses a bug rather than an enhancement or cleanup, sending
> > it individually with the 'net' tag will help facilitate applying this patch to
> > the net tree.
> > 
> > Ciao,
> > Andrea
> 
> Then there would be a merge conflict between the two patchsets.
> 
> I can do that if you want, but then I'd probably have to wait for this
> patch to reach net-next before the rest can proceed.

I guess patches 2 and 3 have to wait for "ipv6: sr: validate HMAC
algorithm ID in seg6_hmac_info_add" anyway, as they conflict with that
too.  Okay, I resent patch 1 as a standalone patch targeting "net":
https://lore.kernel.org/netdev/20250818202724.15713-1-ebiggers@kernel.org/

- Eric