lkml.org 
[lkml]   [2018]   [Jul]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v1 07/10] Input: atmel_mxt_ts - zero terminate config firmware file
On Mon, Jul 23, 2018 at 03:35:34PM -0700, Dmitry Torokhov wrote:
> On Fri, Jul 20, 2018 at 10:51:19PM +0100, Nick Dyer wrote:
> > From: Nick Dyer <nick.dyer@itdev.co.uk>
> >
> > We use sscanf to parse the configuration file, so it's necessary to zero
> > terminate the configuration otherwise a truncated file can cause the
> > parser to run off into uninitialised memory.
> >
> > Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
> > ---
> > drivers/input/touchscreen/atmel_mxt_ts.c | 36 +++++++++++++++++-------
> > 1 file changed, 26 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
> > index 0ce126e918f1..2d1fddafb7f9 100644
> > --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> > +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> > @@ -279,7 +279,7 @@ enum mxt_suspend_mode {
> >
> > /* Config update context */
> > struct mxt_cfg {
> > - const u8 *raw;
> > + u8 *raw;
> > size_t raw_size;
> > off_t raw_pos;
> >
> > @@ -1451,14 +1451,21 @@ static int mxt_update_cfg(struct mxt_data *data, const struct firmware *fw)
> > u32 info_crc, config_crc, calculated_crc;
> > u16 crc_start = 0;
> >
> > - cfg.raw = fw->data;
> > + /* Make zero terminated copy of the OBP_RAW file */
> > + cfg.raw = kzalloc(fw->size + 1, GFP_KERNEL);
>
> kmemdup_nul()? I guess config it not that big to be concerned with
> kmalloc() vs vmalloc() and allocation failures...

Yes, that looks like it should work. There's a limit on the size of the
data due to the I2C address space, so we should be fine.

Nick

\
 
 \ /
  Last update: 2018-07-24 22:44    [W:1.355 / U:0.000 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site