Re: [PATCH] net: mana: Fix memory leak in mana_gd_setup_irqs

[Maxim Levitsky <mlevitsk@redhat.com>]

On Tue, 2024-12-03 at 16:21 +0000, Simon Horman wrote:
> On Thu, Nov 28, 2024 at 09:49:35PM +0000, Michael Kelley wrote:
> > From: Maxim Levitsky <mlevitsk@redhat.com> Sent: Thursday, November 28, 2024 11:43 AM
> > > Commit 8afefc361209 ("net: mana: Assigning IRQ affinity on HT cores")
> > > added memory allocation in mana_gd_setup_irqs of 'irqs' but the code
> > > doesn't free this temporary array in the success path.
> > > 
> > > This was caught by kmemleak.
> > > 
> > > Fixes: 8afefc361209 ("net: mana: Assigning IRQ affinity on HT cores")
> > > Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
> > > ---
> > >  drivers/net/ethernet/microsoft/mana/gdma_main.c | 1 +
> > >  1 file changed, 1 insertion(+)
> > > 
> > > diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c
> > > b/drivers/net/ethernet/microsoft/mana/gdma_main.c
> > > index e97af7ac2bb2..aba188f9f10f 100644
> > > --- a/drivers/net/ethernet/microsoft/mana/gdma_main.c
> > > +++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c
> > > @@ -1375,6 +1375,7 @@ static int mana_gd_setup_irqs(struct pci_dev *pdev)
> > >  	gc->max_num_msix = nvec;
> > >  	gc->num_msix_usable = nvec;
> > >  	cpus_read_unlock();
> > > +	kfree(irqs);
> > >  	return 0;
> > > 
> > >  free_irq:
> > 
> > FWIW, there's a related error path leak. If the kcalloc() to populate
> > gc->irq_contexts fails, the irqs array is not freed. Probably could
> > extend this patch to fix that leak as well.
> 
> Yes, as that problem also appears to be introduced by the cited commit
> I agree it would be good to fix them both in one patch.
> 
I'll send a v2 tomorrow. Thanks for the review!

Best regards,
	Maxim Levitsky