[PATCH 5.17 120/225] net: lan966x: fix a couple off by one bugs

From: Greg Kroah-Hartman
Date: Wed May 04 2022 - 13:43:23 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit 9810c58c7051ae83e7ac326fca3daa823da6b778 ]

The lan966x->ports[] array has lan966x->num_phys_ports elements. These
are assigned in lan966x_probe(). That means the > comparison should be
changed to >=.

The first off by one check is harmless but the second one could lead to
an out of bounds access and a crash.

Fixes: 5ccd66e01cbe ("net: lan966x: add support for interrupts from analyzer")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/microchip/lan966x/lan966x_mac.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_mac.c b/drivers/net/ethernet/microchip/lan966x/lan966x_mac.c
index 2679111ef669..005e56ea5da1 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_mac.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_mac.c
@@ -346,7 +346,7 @@ static void lan966x_mac_irq_process(struct lan966x *lan966x, u32 row,

lan966x_mac_process_raw_entry(&raw_entries[column],
mac, &vid, &dest_idx);
- if (WARN_ON(dest_idx > lan966x->num_phys_ports))
+ if (WARN_ON(dest_idx >= lan966x->num_phys_ports))
continue;

/* If the entry in SW is found, then there is nothing
@@ -393,7 +393,7 @@ static void lan966x_mac_irq_process(struct lan966x *lan966x, u32 row,

lan966x_mac_process_raw_entry(&raw_entries[column],
mac, &vid, &dest_idx);
- if (WARN_ON(dest_idx > lan966x->num_phys_ports))
+ if (WARN_ON(dest_idx >= lan966x->num_phys_ports))
continue;

mac_entry = lan966x_mac_alloc_entry(mac, vid, dest_idx);
--
2.35.1