Re: [lvc-project] [PATCH] net-wan: Add check for NULL for utdm in ucc_hdlc_probe

[Alexey Khoroshilov]

On 23.12.2022 17:32, Ekaterina Esina wrote:
> If uhdlc_priv_tsa != 1 then utdm is not initialized.
> And if ret != NULL then goto undo_uhdlc_init, where utdm is dereferenced.
> Same if dev == NULL.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Signed-off-by: Ekaterina Esina <eesina@xxxxxxxxxxxxx>
> ---
>  drivers/net/wan/fsl_ucc_hdlc.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
> index 22edea6ca4b8..2ddb0f71e648 100644
> --- a/drivers/net/wan/fsl_ucc_hdlc.c
> +++ b/drivers/net/wan/fsl_ucc_hdlc.c
> @@ -1243,7 +1243,9 @@ static int ucc_hdlc_probe(struct platform_device *pdev)
>  free_dev:
>  	free_netdev(dev);
>  undo_uhdlc_init:
> -	iounmap(utdm->siram);
> +	if (utdm != NULL) {
> +		iounmap(utdm->siram);
> +	}
>  unmap_si_regs:
>  	iounmap(utdm->si_regs);
>  free_utdm:


But what is about iounmap(utdm->si_regs); that dereferences utdm a few
lines below?

--
Alexey