linux-kernel - Re: [PATCH v0] idb: Add rtnl

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] [day] [month] [year] [list]

Message-ID: <35502986.7352e.18280905841.Coremail.linma@zju.edu.cn>
Date:   Tue, 9 Aug 2022 11:05:19 +0800 (GMT+08:00)
From:   "Lin Ma" <linma@....edu.cn>
To:     "Jakub Kicinski" <kuba@...nel.org>
Cc:     jesse.brandeburg@...el.com, anthony.l.nguyen@...el.com,
        davem@...emloft.net, edumazet@...gle.com, pabeni@...hat.com,
        ast@...nel.org, daniel@...earbox.net, hawk@...nel.org,
        john.fastabend@...il.com, intel-wired-lan@...ts.osuosl.org,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        bpf@...r.kernel.org
Subject: Re: [PATCH v0] idb: Add rtnl_lock to avoid data race

Hello there,

> 
> What about the disable path coming from sysfs? This looks incomplete to
> me. Perhaps take a look at commit 1e53834ce541 ("ixgbe: Add locking to
> prevent panic when setting sriov_numvfs to zero") for some inspiration.

Thanks for the advice, I sent the new version of the patch which uses a new spinlock to avoid race cases such as described in commit 1e53834ce541.

Additionally, I also keep the rtnl_lock to eliminate the races that come from netdev core. Although this can also be handled with the newly added spinlock, I found that adding the spinlock every time accessing the VF resources is not trivial.
(If you think that keep using the spinlock is better I will craft a new version of patch)

It seems that ixgbe_disable_sriov also suffers from the mentioned races from netdev core. If you think the rtnl_lock solution is fine, I will also send a patch for that driver too.

Thanks
Lin Ma