netdev - Re: [PATCH] net: fec: Fixed panic problem with non-tso

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]

Date:   Tue, 17 Jan 2017 20:21:23 -0800
From:   Eric Dumazet <eric.dumazet@...il.com>
To:     "Ashizuka, Yuusuke" <ashiduka@...fujitsu.com>
Cc:     Andy Duan <fugang.duan@....com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: [PATCH] net: fec: Fixed panic problem with non-tso

On Wed, 2017-01-18 at 03:12 +0000, Ashizuka, Yuusuke wrote:

> indeed.
> 
> In the case of TSO with i.MX6 system (highmem enabled) with 2GB memory,
> "this_frag->page.p" did not become highmem area.
> (We confirmed by transferring about 100MB of files)
> 
> However, in the case of non-tso on an i.MX6 system with 2GB of memory,
> "this_frag->page.p" may become a highmem area.
> (Occurred with approximately 2MB of file transfer)
> 
> For non-tso only, I do not know the reason why "this_frag-> page.p" 
> in this driver shows highmem area.

This worries me, since this driver does not set NETIF_F_HIGHDMA in its
features.

No packet should be given to this driver with a highmem fragment

Check is done in illegal_highdma() in net/core/dev.c