Re: [PATCH] mfd: fix a potential NULL pointer dereference

[Lee Jones <lee.jones@linaro.org>]

On Fri, 22 Mar 2019, Kangjie Lu wrote:

> Hi Lee Jones,
> 
> Can you review this patch?

Don't poke.

I have a very long list of reviews on my TODO.  Poking only surfaces
your patch to the top of my Inbox, and since I review patches in
reverse chronological order, it puts the review to the back of the
queue.

> > On Mar 9, 2019, at 2:04 AM, Kangjie Lu <kjlu@umn.edu> wrote:
> > 
> > In case devm_kzalloc fails, the fix does NULL check and returns
> > -ENOMEM upon failure so as to avoid NULL pointer dereference.
> > 
> > Signed-off-by: Kangjie Lu <kjlu@umn.edu>
> > ---
> > drivers/mfd/sm501.c | 3 +++
> > 1 file changed, 3 insertions(+)
> > 
> > diff --git a/drivers/mfd/sm501.c b/drivers/mfd/sm501.c
> > index a530972c5a7e..e0173bf4b0dc 100644
> > --- a/drivers/mfd/sm501.c
> > +++ b/drivers/mfd/sm501.c
> > @@ -1145,6 +1145,9 @@ static int sm501_register_gpio_i2c_instance(struct sm501_devdata *sm,
> > 	lookup = devm_kzalloc(&pdev->dev,
> > 			      sizeof(*lookup) + 3 * sizeof(struct gpiod_lookup),
> > 			      GFP_KERNEL);
> > +	if (!lookup)
> > +		return -ENOMEM;
> > +
> > 	lookup->dev_id = "i2c-gpio";
> > 	if (iic->pin_sda < 32)
> > 		lookup->table[0].chip_label = "SM501-LOW";
> 

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog