linux-kernel - Re: [PATCH] dma-remap: Avoid de-referencing NULL atomic

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: <3d19909d-0b1b-5641-6698-6bd38c924f81@gmail.com>
Date:   Tue, 11 Jun 2019 09:44:47 -0700
From:   Florian Fainelli <f.fainelli@...il.com>
To:     Christoph Hellwig <hch@....de>,
        Florian Fainelli <f.fainelli@...il.com>
Cc:     linux-kernel@...r.kernel.org,
        bcm-kernel-feedback-list@...adcom.com, akpm@...ux-foundation.org,
        alexey.skidanov@...el.com, olof@...om.net, sjhuang@...vatar.ai,
        Marek Szyprowski <m.szyprowski@...sung.com>,
        Robin Murphy <robin.murphy@....com>,
        "open list:DMA MAPPING HELPERS" <iommu@...ts.linux-foundation.org>
Subject: Re: [PATCH] dma-remap: Avoid de-referencing NULL atomic_pool

On 6/10/19 10:26 PM, Christoph Hellwig wrote:
> Looks good to me.  When did this start to show up?  Do we need
> to push it to Linus this cycle and cc stable?

You need a really contrived memory map layout to reach that situation,
so I don't think it warrants a stable backport.

For ARM64, this seems to date back to 3.18 with
d4932f9e81ae7a7bf3c3967e48373909b9c98ee5 ("arm64: add atomic pool for
non-coherent and CMA allocations") and for ARM 32-bit, I don't think you
could hit that condition since it would mean no lowmem, which would not
lead to a working kernel.
-- 
Florian