linux-kernel - Re: [PATCH v3 11/41] media/v4l2-core/mm: convert put_page() to put_user

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: <8a02b10a-507b-2eb3-19aa-1cb498c1a4af@xs4all.nl>
Date:   Wed, 7 Aug 2019 10:07:02 +0200
From:   Hans Verkuil <hverkuil-cisco@...all.nl>
To:     john.hubbard@...il.com, Andrew Morton <akpm@...ux-foundation.org>
Cc:     Christoph Hellwig <hch@...radead.org>,
        Dan Williams <dan.j.williams@...el.com>,
        Dave Chinner <david@...morbit.com>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Ira Weiny <ira.weiny@...el.com>, Jan Kara <jack@...e.cz>,
        Jason Gunthorpe <jgg@...pe.ca>,
        Jérôme Glisse <jglisse@...hat.com>,
        LKML <linux-kernel@...r.kernel.org>,
        amd-gfx@...ts.freedesktop.org, ceph-devel@...r.kernel.org,
        devel@...verdev.osuosl.org, devel@...ts.orangefs.org,
        dri-devel@...ts.freedesktop.org, intel-gfx@...ts.freedesktop.org,
        kvm@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-block@...r.kernel.org, linux-crypto@...r.kernel.org,
        linux-fbdev@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        linux-media@...r.kernel.org, linux-mm@...ck.org,
        linux-nfs@...r.kernel.org, linux-rdma@...r.kernel.org,
        linux-rpi-kernel@...ts.infradead.org, linux-xfs@...r.kernel.org,
        netdev@...r.kernel.org, rds-devel@....oracle.com,
        sparclinux@...r.kernel.org, x86@...nel.org,
        xen-devel@...ts.xenproject.org, John Hubbard <jhubbard@...dia.com>,
        Mauro Carvalho Chehab <mchehab@...nel.org>,
        Kees Cook <keescook@...omium.org>,
        Hans Verkuil <hans.verkuil@...co.com>,
        Sakari Ailus <sakari.ailus@...ux.intel.com>,
        Robin Murphy <robin.murphy@....com>,
        Souptick Joarder <jrdr.linux@...il.com>
Subject: Re: [PATCH v3 11/41] media/v4l2-core/mm: convert put_page() to
 put_user_page*()

On 8/7/19 3:33 AM, john.hubbard@...il.com wrote:
> From: John Hubbard <jhubbard@...dia.com>
> 
> For pages that were retained via get_user_pages*(), release those pages
> via the new put_user_page*() routines, instead of via put_page() or
> release_pages().
> 
> This is part a tree-wide conversion, as described in commit fc1d8e7cca2d
> ("mm: introduce put_user_page*(), placeholder versions").
> 
> Cc: Mauro Carvalho Chehab <mchehab@...nel.org>
> Cc: Kees Cook <keescook@...omium.org>
> Cc: Hans Verkuil <hans.verkuil@...co.com>
> Cc: Sakari Ailus <sakari.ailus@...ux.intel.com>
> Cc: Jan Kara <jack@...e.cz>
> Cc: Robin Murphy <robin.murphy@....com>
> Cc: Souptick Joarder <jrdr.linux@...il.com>
> Cc: Dan Williams <dan.j.williams@...el.com>
> Cc: linux-media@...r.kernel.org
> Signed-off-by: John Hubbard <jhubbard@...dia.com>

Acked-by: Hans Verkuil <hverkuil-cisco@...all.nl>

> ---
>  drivers/media/v4l2-core/videobuf-dma-sg.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/media/v4l2-core/videobuf-dma-sg.c b/drivers/media/v4l2-core/videobuf-dma-sg.c
> index 66a6c6c236a7..d6eeb437ec19 100644
> --- a/drivers/media/v4l2-core/videobuf-dma-sg.c
> +++ b/drivers/media/v4l2-core/videobuf-dma-sg.c
> @@ -349,8 +349,7 @@ int videobuf_dma_free(struct videobuf_dmabuf *dma)
>  	BUG_ON(dma->sglen);
>  
>  	if (dma->pages) {
> -		for (i = 0; i < dma->nr_pages; i++)
> -			put_page(dma->pages[i]);
> +		put_user_pages(dma->pages, dma->nr_pages);
>  		kfree(dma->pages);
>  		dma->pages = NULL;
>  	}
>