From: Diana Craciun OSS <diana.craciun@oss.nxp.com>
To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Alex Williamson <alex.williamson@redhat.com>,
Cornelia Huck <cohuck@redhat.com>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
kernel-janitors@vger.kernel.org
Subject: Re: [PATCH 2/2] vfio/fsl-mc: prevent underflow in vfio_fsl_mc_mmap()
Date: Tue, 3 Nov 2020 14:03:08 +0200 [thread overview]
Message-ID: <de18ce14-9138-dcc4-253f-fa50d63b3ae2@oss.nxp.com> (raw)
In-Reply-To: <20201023112947.GF282278@mwanda>
Acked-by: Diana Craciun <diana.craciun@oss.nxp.com>
On 10/23/2020 2:29 PM, Dan Carpenter wrote:
> My static analsysis tool complains that the "index" can be negative.
> There are some checks in do_mmap() which try to prevent underflows but
> I don't know if they are sufficient for this situation. Either way,
> making "index" unsigned is harmless so let's do it just to be safe.
>
> Fixes: 67247289688d ("vfio/fsl-mc: Allow userspace to MMAP fsl-mc device MMIO regions")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> drivers/vfio/fsl-mc/vfio_fsl_mc.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> index 21f22e3da11f..f27e25112c40 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> @@ -472,7 +472,7 @@ static int vfio_fsl_mc_mmap(void *device_data, struct vm_area_struct *vma)
> {
> struct vfio_fsl_mc_device *vdev = device_data;
> struct fsl_mc_device *mc_dev = vdev->mc_dev;
> - int index;
> + unsigned int index;
>
> index = vma->vm_pgoff >> (VFIO_FSL_MC_OFFSET_SHIFT - PAGE_SHIFT);
>
>
prev parent reply other threads:[~2020-11-03 12:03 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-23 11:29 [PATCH 2/2] vfio/fsl-mc: prevent underflow in vfio_fsl_mc_mmap() Dan Carpenter
2020-11-02 21:45 ` Alex Williamson
2020-11-03 12:03 ` Diana Craciun OSS [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=de18ce14-9138-dcc4-253f-fa50d63b3ae2@oss.nxp.com \
--to=diana.craciun@oss.nxp.com \
--cc=alex.williamson@redhat.com \
--cc=cohuck@redhat.com \
--cc=dan.carpenter@oracle.com \
--cc=kernel-janitors@vger.kernel.org \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox