[PATCH net v3 5/7] octeon_ep_vf: Fix null dereferences to IQ/OQ pointers

[Shinas Rasheed]

During unload, sometimes race scenarios are seen wherein
the get stats callback proceeds to retrieve the IQ/OQ stats,
but by then the IQ/OQ might have been already freed.

Protect against such conditions by defensively checking if
the IQ/OQ pointers are null before dereference.

Fixes: cb7dd712189f ("octeon_ep_vf: Add driver framework and device initialization")
Signed-off-by: Shinas Rasheed <srasheed@xxxxxxxxxxx>
---
V3:
  - Added back "Fixes" to the changelist

V2: https://lore.kernel.org/all/20241107132846.1118835-6-srasheed@xxxxxxxxxxx/
  - Split into a separate patch
  - Added more context

V1: https://lore.kernel.org/all/20241101103416.1064930-4-srasheed@xxxxxxxxxxx/

 drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_main.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_main.c b/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_main.c
index 7e6771c9cdbb..79d9ffd593eb 100644
--- a/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_main.c
+++ b/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_main.c
@@ -790,6 +790,9 @@ static void octep_vf_get_stats64(struct net_device *netdev,
 		struct octep_vf_iq *iq = oct->iq[q];
 		struct octep_vf_oq *oq = oct->oq[q];
 
+		if (!iq || !oq)
+			return;
+
 		tx_packets += iq->stats.instr_completed;
 		tx_bytes += iq->stats.bytes_sent;
 		rx_packets += oq->stats.packets;
-- 
2.25.1