RE: [PATCH] net/af_xdp: fix resources leak when xsk configure fails

[wangyunjian <wangyunjian@huawei.com>]

> -----Original Message-----
> From: Loftus, Ciara [mailto:ciara.loftus@intel.com]
> Sent: Thursday, February 22, 2024 7:06 PM
> To: Tahhan, Maryam <mtahhan@redhat.com>; wangyunjian
> <wangyunjian@huawei.com>
> Cc: dev@dpdk.org; ferruh.yigit@amd.com; stable@dpdk.org
> Subject: RE: [PATCH] net/af_xdp: fix resources leak when xsk configure fails
> 
> >
> > On 22/02/2024 03:07, Yunjian Wang wrote:
> > In xdp_umem_configure() allocated some resources for the xsk umem, we
> > should delete them when xsk configure fails, otherwise it will lead to
> > resources leak.
> >
> > Fixes: f1debd77efaf ("net/af_xdp: introduce AF_XDP PMD")
> > Cc: mailto:stable@dpdk.org
> >
> > Signed-off-by: Yunjian Wang mailto:wangyunjian@huawei.com
> > ---
> >  drivers/net/af_xdp/rte_eth_af_xdp.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c
> > b/drivers/net/af_xdp/rte_eth_af_xdp.c
> > index 2d151e45c7..8b8b2cff9f 100644
> > --- a/drivers/net/af_xdp/rte_eth_af_xdp.c
> > +++ b/drivers/net/af_xdp/rte_eth_af_xdp.c
> > @@ -1723,8 +1723,10 @@ xsk_configure(struct pmd_internals *internals,
> > struct pkt_rx_queue *rxq,
> >  out_xsk:
> >  	xsk_socket__delete(rxq->xsk);
> >  out_umem:
> > -	if (__atomic_fetch_sub(&rxq->umem->refcnt, 1,
> > __ATOMIC_ACQUIRE) - 1 == 0)
> > +	if (__atomic_fetch_sub(&rxq->umem->refcnt, 1,
> > __ATOMIC_ACQUIRE) - 1 == 0) {
> > +		(void)xsk_umem__delete(rxq->umem->umem);
> >  		xdp_umem_destroy(rxq->umem);
> > +	}
> >
> >  	return ret;
> >  }
> >
> > Does it make sense to: move `xsk_umem__delete()` inside
> > `xdp_umem_destroy()` to be invoked after a NULL check for `umem->umem`
> > and then fixup the places where both functions are called to only
> > invoke `xdp_umem_destroy()`? (Keeping all the umem cleanup code in one
> > place) @Yunjian WDYT?
> >
> > @Ciara WDYT?
> 
> Thanks for the patch Yunjian.
> 
> @Maryam +1 for the suggestion I think it would be a good optimisation for the
> cleanup code.

OK, I will update it in next version.

> 
> Thanks,
> Ciara
> 
> >