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

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

On Mon, 25 Mar 2019, Mukesh Ojha wrote:

> On 3/25/2019 1:26 PM, Lee Jones wrote:
> > 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;
> 
> Seems you are using quite old codebase.
> This patch is already there ..
> 
> https://elixir.bootlin.com/linux/v5.1-rc2/source/drivers/mfd/sm501.c#L1147
> 
> commit ae7b8eda27b3( mfd: sm501: Fix potential NULL pointer dereference )

Confirmed.  Dropping this one.

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
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