From: Vladimir Oltean <vladimir.oltean@xxxxxxx> [ Upstream commit ff91e1b68490b97c18c649b769618815eb945f11 ] The cross-chip notifier boilerplate code meant to check the presence of ds->ops->port_mrp_add_ring_role before calling it, but checked ds->ops->port_mrp_add instead, before calling ds->ops->port_mrp_add_ring_role. Therefore, a driver which implements one operation but not the other would trigger a NULL pointer dereference. There isn't any such driver in DSA yet, so there is no reason to backport the change. Issue found through code inspection. Cc: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx> Fixes: c595c4330da0 ("net: dsa: add MRP support") Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/dsa/switch.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/dsa/switch.c b/net/dsa/switch.c index 44558fbdc65b3..fb69f2f14234e 100644 --- a/net/dsa/switch.c +++ b/net/dsa/switch.c @@ -644,7 +644,7 @@ static int dsa_switch_mrp_add_ring_role(struct dsa_switch *ds, struct dsa_notifier_mrp_ring_role_info *info) { - if (!ds->ops->port_mrp_add) + if (!ds->ops->port_mrp_add_ring_role) return -EOPNOTSUPP; if (ds->index == info->sw_index) @@ -658,7 +658,7 @@ static int dsa_switch_mrp_del_ring_role(struct dsa_switch *ds, struct dsa_notifier_mrp_ring_role_info *info) { - if (!ds->ops->port_mrp_del) + if (!ds->ops->port_mrp_del_ring_role) return -EOPNOTSUPP; if (ds->index == info->sw_index) -- 2.34.1