linux-kernel - Re: [PATCH v9] Input: synaptics-rmi4 - add support for F34 V7 bootloader

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

Date:   Mon, 12 Dec 2016 11:03:19 -0800
From:   Dmitry Torokhov <dmitry.torokhov@...il.com>
To:     Nick Dyer <nick@...anahar.org>
Cc:     Andrew Duggan <aduggan@...aptics.com>,
        Chris Healy <cphealy@...il.com>,
        Henrik Rydberg <rydberg@...math.org>,
        Benjamin Tissoires <benjamin.tissoires@...hat.com>,
        Linus Walleij <linus.walleij@...aro.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        linux-input@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v9] Input: synaptics-rmi4 - add support for F34 V7
 bootloader

On Sun, Dec 11, 2016 at 08:16:31PM +0000, Nick Dyer wrote:
> On Sun, Dec 11, 2016 at 12:03:49AM -0800, Dmitry Torokhov wrote:
> > On Sun, Dec 11, 2016 at 12:18:26AM +0000, Nick Dyer wrote:
> > > +static void rmi_f34v7_parse_img_header_10_bl_container(struct f34_data *f34,
> > > +						       const u8 *image)
> > > +{
> > > +	int i;
> > > +	int num_of_containers;
> > > +	unsigned int addr;
> > > +	unsigned int container_id;
> > > +	unsigned int length;
> > > +	const u8 *content;
> > > +	struct container_descriptor *descriptor;
> > > +
> > > +	BUG_ON(f34->v7.img.bootloader.size < 4);
> > 
> > Killing the box because you got bad firmware is not very nice...
> > 
> > > +
> > > +	num_of_containers = (f34->v7.img.bootloader.size - 4) / 4;
> > 
> > Wouldn't
> > 
> > 	num_of_containes = f34->v7.img.bootloader.size / 4 - 1;
> > 
> > give the same result but be less "suspicious". The variable is 'int' so
> > for size < 4 we'll get a negative and the loop won't execute.
> 
> Neat!
> 
> > > +
> > > +	for (i = 1; i <= num_of_containers; i++) {
> > > +		addr = get_unaligned_le32(f34->v7.img.bootloader.data + i*4);
> > > +		descriptor = (struct container_descriptor *)(image + addr);
> > 
> > This casts away constness, which is not nice. DOes it still work if you
> > apply the below on top?
> 
> I've run it through a few flash cycles with no issues.
> 
> Tested-by: Nick Dyer <nick@...anahar.org>

Great, I'll fold and apply then. Thanks!

-- 
Dmitry