RE: [PATCH] function mana_hwc_create_wq leaks memory

From: Dexuan Cui
Date: Thu Jun 10 2021 - 13:28:16 EST


> From: Dexuan Cui <decui@xxxxxxxxxxxxx>
> Sent: Thursday, June 10, 2021 10:18 AM
> ...
> > diff --git a/drivers/net/ethernet/microsoft/mana/hw_channel.c
> > b/drivers/net/ethernet/microsoft/mana/hw_channel.c
> > index 1a923fd99990..4aa4bda518fb 100644
> > --- a/drivers/net/ethernet/microsoft/mana/hw_channel.c
> > +++ b/drivers/net/ethernet/microsoft/mana/hw_channel.c
> > @@ -501,8 +501,10 @@ static int mana_hwc_create_wq(struct
> > hw_channel_context *hwc,
> > *hwc_wq_ptr = hwc_wq;
> > return 0;
> > out:
> > - if (err)
> > + if (err) {
>
> Here the 'err' must be non-zero. Can you please remove this 'if'?
>
> > + kfree(queue);
> > mana_hwc_destroy_wq(hwc, hwc_wq);
> > + }
> > return err;
> > }
>
> Reviewed-by: Dexuan Cui <decui@xxxxxxxxxxxxx>

Hi Dhiraj,
I checked the code again and it looks like your patch is actually
unnecessary as IMO there is no memory leak here: the 'queue'
pointer is passed to mana_hwc_destroy_wq() as hwc_wq->gdma_wq,
and is later freed in mana_gd_destroy_queue() ->
mana_gd_destroy_queue().

The 'if' test can be removed as the 'err's is always non-zero there.

Thanks,
Dexuan