Re: [PATCH] ice: Fix some null pointer dereference issues in ice_ptp.c

[Przemek Kitszel]

On 12/11/23 10:32, Kunwu Chan wrote:
> Thanks for your suggestion.
>
> I made the patch based on linux-next.git(tag:next-20231211).
>
> Our code is just self-similar, i didn't override the old name.
> I keep the logic as it was before.
> The newest code is:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/net/ethernet/intel/ice/ice_ptp.c#n2747
>
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/net/ethernet/intel/ice/ice_ptp.c#n2993

sure, I just checked those, no huge benefit of dedup

> I'll update v2 patch with:
> 1. update suject prefix to "[PATCH v2 iwl-next]"
> 2. remove 'dev_err'
>
>
> Thanks again,
> Kunwu

Thank you too

> On 2023/12/11 15:15, Przemek Kitszel wrote:
> > On 12/11/23 07:26, Kunwu Chan wrote:
> > > devm_kasprintf() returns a pointer to dynamically allocated memory
> > > which can be NULL upon failure.
> > >
> > > Fixes: d938a8cca88a ("ice: Auxbus devices & driver for E822 TS")
> > > Cc: Kunwu Chan <kunwu.chan@xxxxxxxxxxx>
> > > Signed-off-by: Kunwu Chan <chentao@xxxxxxxxxx>
> >
> > I would suggest adding "iwl-net" as a target here
> >
> > > ---
> > >   drivers/net/ethernet/intel/ice/ice_ptp.c | 6 ++++++
> > >   1 file changed, 6 insertions(+)
> > >
> > > diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c 
> > > b/drivers/net/ethernet/intel/ice/ice_ptp.c
> > > index 1eddcbe89b0c..59794ce4f243 100644
> > > --- a/drivers/net/ethernet/intel/ice/ice_ptp.c
> > > +++ b/drivers/net/ethernet/intel/ice/ice_ptp.c
> > > @@ -2668,6 +2668,8 @@ static int 
> > > ice_ptp_register_auxbus_driver(struct ice_pf *pf)
> > >       name = devm_kasprintf(dev, GFP_KERNEL, "ptp_aux_dev_%u_%u_clk%u",
> > >                     pf->pdev->bus->number, PCI_SLOT(pf->pdev->devfn),
> > >                     ice_get_ptp_src_clock_index(&pf->hw));
> > > +    if (!name)
> > > +        return -ENOMEM;
> > >       aux_driver->name = name;
> > >       aux_driver->shutdown = ice_ptp_auxbus_shutdown;
> > > @@ -2929,6 +2931,10 @@ static int ice_ptp_create_auxbus_device(struct 
> > > ice_pf *pf)
> > >       name = devm_kasprintf(dev, GFP_KERNEL, "ptp_aux_dev_%u_%u_clk%u",
> > >                     pf->pdev->bus->number, PCI_SLOT(pf->pdev->devfn),
> > >                     ice_get_ptp_src_clock_index(&pf->hw));
> > > +    if (!name) {
> > > +        dev_err(dev, "Failed to allocate memory\n");
> >
> > Kuba @ [1]:
> > no warnings on allocation failures, there will be a splat for GFP_KERNEL
> > (checkpatch should catch this)
> >
> > [1] https://lore.kernel.org/netdev/20231206195304.6226771d@xxxxxxxxxx/T/
> >
> > so just "return -ENOMEM" would be sufficient
> >
> > > +        return -ENOMEM;
> > > +    }
> > >       aux_dev->name = name;
> > >       aux_dev->id = id;
> >
> > I didn't checked but having same code in two places raises questions.
> > Are you overwriting old name here, or our code is just self similar?