linux-kernel - Re: [PATCH] gspca: add missing .type field check in VIDIOC_G

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: <49C1DD0C.4050500@freemail.hu>
Date:	Thu, 19 Mar 2009 06:50:04 +0100
From:	Németh Márton <nm127@...email.hu>
To:	David Ellingsworth <david@...ntd.dyndns.org>
CC:	Jean-Francois Moine <moinejf@...e.fr>, linux-media@...r.kernel.org,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] gspca: add missing .type field check in VIDIOC_G_PARM

David Ellingsworth wrote:
> 2009/3/18 Németh Márton <nm127@...email.hu>:
>> From: Márton Németh <nm127@...email.hu>
>>
>> The gspca webcam driver does not check the .type field of struct v4l2_streamparm.
>> This field is an input parameter for the driver according to V4L2 API specification,
>> revision 0.24 [1]. Add the missing check.
>>
>> The missing check was recognised by v4l-test 0.10 [2] together with gspca_sunplus driver
>> and with "Trust 610 LCD POWERC@M ZOOM" webcam. This patch was verified also with
>> v4l-test 0.10.
>>
>> References:
>> [1] V4L2 API specification, revision 0.24
>>    http://v4l2spec.bytesex.org/spec/r11680.htm
>>
>> [2] v4l-test: Test environment for Video For Linux Two API
>>    http://v4l-test.sourceforge.net/
>>
>> Signed-off-by: Márton Németh <nm127@...email.hu>
>> ---
>> --- linux-2.6.29-rc8/drivers/media/video/gspca/gspca.c.orig     2009-03-14 12:29:38.000000000 +0100
>> +++ linux-2.6.29-rc8/drivers/media/video/gspca/gspca.c  2009-03-18 16:51:03.000000000 +0100
>> @@ -1320,6 +1320,9 @@ static int vidioc_g_parm(struct file *fi
>>  {
>>        struct gspca_dev *gspca_dev = priv;
>>
>> +       if (parm->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
>> +               return -EINVAL;
>> +
>>        memset(parm, 0, sizeof *parm);
>>        parm->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> ^^^^^^^^^^^^^^^^^^^
> This line should be deleted as it's no longer needed.

Because memset() clears the whole parm structure this line is necessary. In other
drivers the following code is there:

    tmp = parm->type;
    memset(parm, 0, sizeof(*parm));
    parm->type = parm;

Maybe changing the code similar to this would be easier to read?

	Márton Németh
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/