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

From: Gustavo A. R. Silva
Date: Sat Mar 02 2019 - 16:26:15 EST




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 <pakki001@xxxxxxx>
> ---
> 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;
>