netdev - Re: [PATCH v2 net-next] net: make skb_set_owner

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:	Mon, 02 Nov 2015 15:26:10 -0500 (EST)
From:	David Miller <davem@...emloft.net>
To:	eric.dumazet@...il.com
Cc:	haiyangz@...rosoft.com, edumazet@...gle.com,
	netdev@...r.kernel.org, kys@...rosoft.com
Subject: Re: [PATCH v2 net-next] net: make skb_set_owner_w() more robust

From: Eric Dumazet <eric.dumazet@...il.com>
Date: Mon, 02 Nov 2015 12:09:25 -0800

> On Mon, 2015-11-02 at 20:05 +0000, Haiyang Zhang wrote:
> 
>> Thanks for the fix!
>> For some driver, like ours, this condition may not be "unlikely".
>> So could you remove the "unlikely"?
> 
> No, I wont remove the unlikely.
> 
> Look, your main issue is about reallocating skbs, because of excessive
> dev->needed_headroom.
> 
> An unlikely() mismatch is 1000 times less expensive, why would you
> care ?
> 
> If you really care, fix your driver to not abuse skb->head to store 220
> bytes of private data.

+1

And I've been saying this from the beginning.  This driver must place
it's private per-packet data in another location if it wants optimal
behavior inside of the Linux networking stack.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html