[PATCH 5.15 153/317] nfp: flower: handle acti_netdevs allocation failure

[Sasha Levin]

From: Duoming Zhou <duoming@xxxxxxxxxx>

[ Upstream commit 84e95149bd341705f0eca6a7fcb955c548805002 ]

The kmalloc_array() in nfp_fl_lag_do_work() will return null, if
the physical memory has run out. As a result, if we dereference
the acti_netdevs, the null pointer dereference bugs will happen.

This patch adds a check to judge whether allocation failure occurs.
If it happens, the delayed work will be rescheduled and try again.

Fixes: bb9a8d031140 ("nfp: flower: monitor and offload LAG groups")
Signed-off-by: Duoming Zhou <duoming@xxxxxxxxxx>
Reviewed-by: Louis Peens <louis.peens@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240308142540.9674-1-duoming@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/netronome/nfp/flower/lag_conf.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c b/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
index 63907aeb3884e..3167f9675ae0f 100644
--- a/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
@@ -308,6 +308,11 @@ static void nfp_fl_lag_do_work(struct work_struct *work)
 
 		acti_netdevs = kmalloc_array(entry->slave_cnt,
 					     sizeof(*acti_netdevs), GFP_KERNEL);
+		if (!acti_netdevs) {
+			schedule_delayed_work(&lag->work,
+					      NFP_FL_LAG_DELAY);
+			continue;
+		}
 
 		/* Include sanity check in the loop. It may be that a bond has
 		 * changed between processing the last notification and the
-- 
2.43.0