Re: [PATCH] isdn: mISDN: Fix potential NULL pointer dereference of kzalloc

[Gustavo A. R. Silva]

On 3/2/19 3:20 PM, Aditya Pakki wrote:
> Allocating memory via kzalloc for phi may fail and causes a
> NULL pointer dereference. This patch avoids such a scenario.
> 

Was this detected by Coccinelle?

If so, please mention it in the commit log.

Thanks
--
Gustavo

> Signed-off-by: Aditya Pakki <pakki...@umn.edu>
> ---
>  drivers/isdn/hardware/mISDN/hfcsusb.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/isdn/hardware/mISDN/hfcsusb.c 
> b/drivers/isdn/hardware/mISDN/hfcsusb.c
> index 124ff530da82..26e3182bbca8 100644
> --- a/drivers/isdn/hardware/mISDN/hfcsusb.c
> +++ b/drivers/isdn/hardware/mISDN/hfcsusb.c
> @@ -263,6 +263,9 @@ hfcsusb_ph_info(struct hfcsusb *hw)
>       int i;
>  
>       phi = kzalloc(struct_size(phi, bch, dch->dev.nrbchan), GFP_ATOMIC);
> +     if (!phi)
> +             return;
> +
>       phi->dch.ch.protocol = hw->protocol;
>       phi->dch.ch.Flags = dch->Flags;
>       phi->dch.state = dch->state;
>