netdev - Re: [PATCH net] xfrm: fix stack access out of bounds with CONFIG_XFRM_SUB

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

Message-ID: <20170421110643.GA13809@gondor.apana.org.au>
Date:   Fri, 21 Apr 2017 19:06:44 +0800
From:   Herbert Xu <herbert@...dor.apana.org.au>
To:     Sabrina Dubroca <sd@...asysnail.net>
Cc:     netdev@...r.kernel.org,
        Steffen Klassert <steffen.klassert@...unet.com>
Subject: Re: [PATCH net] xfrm: fix stack access out of bounds with
 CONFIG_XFRM_SUB_POLICY

On Fri, Apr 21, 2017 at 12:14:51PM +0200, Sabrina Dubroca wrote:
> When CONFIG_XFRM_SUB_POLICY=y, xfrm_dst stores a copy of the flowi for
> that dst. Unfortunately, the code that allocates and fills this copy
> doesn't care about what type of flowi (flowi, flowi4, flowi6) gets
> passed. In multiple code paths (from raw_sendmsg, from TCP when
> replying to a FIN, in vxlan, geneve, and gre), the flowi that gets
> passed to xfrm is actually an on-stack flowi4, so we end up reading
> memory on the stack past the end of the flowi4 struct.
> 
> Since xfrm_dst->origin isn't used anywhere, just get rid of it.
> xfrm_dst->partner isn't used either, so get rid of that too.
> 
> Fixes: ca116922afa8 ("xfrm: Eliminate "fl" and "pol" args to xfrm_bundle_ok().")

The commit you refer to here doesn't seem to have caused this bug.

Thanks,
-- 
Email: Herbert Xu <herbert@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt