netdev - Re: [PATCH v2 net] net/tls: fix encryption error checking

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: <20200519150420.485c800d@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
Date:   Tue, 19 May 2020 15:04:20 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     Vadim Fedorenko <vfedorenko@...ek.ru>
Cc:     Boris Pismenny <borisp@...lanox.com>,
        Aviad Yehezkel <aviadye@...lanox.com>,
        John Fastabend <john.fastabend@...il.com>,
        Daniel Borkmann <daniel@...earbox.net>,
        "David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org
Subject: Re: [PATCH v2 net] net/tls: fix encryption error checking

On Tue, 19 May 2020 13:20:43 +0300 Vadim Fedorenko wrote:
> bpf_exec_tx_verdict() can return negative value for copied
> variable. In that case this value will be pushed back to caller
> and the real error code will be lost. Fix it using signed type and
> checking for positive value.
> 
> Fixes: d10523d0b3d7 ("net/tls: free the record on encryption error")
> Fixes: d3b18ad31f93 ("tls: add bpf support to sk_msg handling")
> Signed-off-by: Vadim Fedorenko <vfedorenko@...ek.ru>

If the error encountered is transient we will still drop some data from
the stream, because the record that was freed may have included data
from a previous send call. Still, cleaning up the error code seems like
an improvement.

John, do you have an opinion on this?