[PATHv2 2/9] net: sandbox: fix NULL pointer derefences

[Sean Anderson]

On 12/26/23 01:18, Maxim Uvarov wrote:
> 
> 
> On Tue, 26 Dec 2023 at 04:43, Sean Anderson <seanga2 at gmail.com <mailto:seanga2 at gmail.com>> wrote:
> 
>     On 12/25/23 10:39, Maxim Uvarov wrote:
>      > Add additional checks for NULL pointers.
>      >
>      > Signed-off-by: Maxim Uvarov <maxim.uvarov at linaro.org <mailto:maxim.uvarov at linaro.org>>
>      > ---
>      >   drivers/net/sandbox.c | 3 +++
>      >   1 file changed, 3 insertions(+)
>      >
>      > diff --git a/drivers/net/sandbox.c b/drivers/net/sandbox.c
>      > index 13022addb6..d91935e032 100644
>      > --- a/drivers/net/sandbox.c
>      > +++ b/drivers/net/sandbox.c
>      > @@ -65,6 +65,9 @@ int sandbox_eth_arp_req_to_reply(struct udevice *dev, void *packet,
>      >       struct ethernet_hdr *eth_recv;
>      >       struct arp_hdr *arp_recv;
>      >
>      > +     if (!priv)
>      > +             return -EAGAIN;
>      > +
> 
>     When can priv be NULL?
> 
>     --Sean
> 
> 
> Function
> struct eth_sandbox_priv *priv = dev_get_priv(dev)
> can return NULL. If you ask why it doesn't return NULL without lwip patches and can return NULL with lwip patch while there is no clear code dependency..
> Then I can not say right now and need additional investigation. But anyway the return code of dev_dev_priv() has to be checked I think.

If you set priv_auto to a nonzero value, dev_get_priv will always return non-null
and does not need to be checked. So this is a NACK from me until you can justify this.

--Sean