netdev - Re: [PATCH v2] iov_iter: don't revert iov buffer if csum error

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: <20170429024647.GO29622@ZenIV.linux.org.uk>
Date:   Sat, 29 Apr 2017 03:46:47 +0100
From:   Al Viro <viro@...IV.linux.org.uk>
To:     Ding Tianhong <dingtianhong@...wei.com>
Cc:     David Miller <davem@...emloft.net>, pabeni@...hat.com,
        edumazet@...gle.com, hannes@...essinduktion.org,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        LinuxArm <linuxarm@...wei.com>,
        "weiyongjun (A)" <weiyongjun1@...wei.com>
Subject: Re: [PATCH v2] iov_iter: don't revert iov buffer if csum error

On Sat, Apr 29, 2017 at 10:38:48AM +0800, Ding Tianhong wrote:
> The patch 327868212381 (make skb_copy_datagram_msg() et.al. preserve
> ->msg_iter on error) will revert the iov buffer if copy to iter
> failed, but it didn't copy any datagram if the skb_checksum_complete
> error, so no need to revert any data at this place.

The bug is real, but I would suggest a simpler fix:
                if (__skb_checksum_complete(skb))
                        return -EINVAL;
leaving the rest as-is.