linux-kernel - Re: [PATCH 1/6] mm: mmap: fix fput in error path

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

Date:   Sat, 10 Oct 2020 01:48:04 +0000
From:   linmiaohe <linmiaohe@...wei.com>
To:     Jason Gunthorpe <jgg@...pe.ca>,
        Andrew Morton <akpm@...ux-foundation.org>
CC:     Christian König 
        <ckoenig.leichtzumerken@...il.com>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linaro-mm-sig@...ts.linaro.org" <linaro-mm-sig@...ts.linaro.org>,
        "dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
        "linux-media@...r.kernel.org" <linux-media@...r.kernel.org>,
        "chris@...is-wilson.co.uk" <chris@...is-wilson.co.uk>,
        "airlied@...hat.com" <airlied@...hat.com>,
        "daniel@...ll.ch" <daniel@...ll.ch>,
        "sumit.semwal@...aro.org" <sumit.semwal@...aro.org>,
        "willy@...radead.org" <willy@...radead.org>,
        "jhubbard@...dia.com" <jhubbard@...dia.com>
Subject: Re: [PATCH 1/6] mm: mmap: fix fput in error path

Jason Gunthorpe <jgg@...pe.ca> wrote:
> On Fri, Oct 09, 2020 at 03:04:20PM -0700, Andrew Morton wrote:
>> On Fri,  9 Oct 2020 17:03:37 +0200 "Christian König" <ckoenig.leichtzumerken@...il.com> wrote:
>> 
>> > Patch "495c10cc1c0c CHROMIUM: dma-buf: restore args..."
>> > adds a workaround for a bug in mmap_region.
>> > 
>> > As the comment states ->mmap() callback can change
>> > vma->vm_file and so we might call fput() on the wrong file.
>> > 
>> > Revert the workaround and proper fix this in mmap_region.
>> > 
>> 
>> Doesn't this patch series address the same thing as 
>> https://lkml.kernel.org/r/20200916090733.31427-1-linmiaohe@huawei.com?
>
>Same basic issue, looks like both of these patches should be combined to plug it fully.
>
>Jason 

I think so too. Both of these patches fix the fput at possible wrong @file due to ->mmap() callback can change vma->vm_file.