[PATCH] net: stmmac: fix off-by-one error in sanity check

From: Arnd Bergmann
Date: Mon Sep 27 2021 - 09:58:59 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

My previous patch had an off-by-one error in the added sanity
check, the arrays are MTL_MAX_{RX,TX}_QUEUES long, so if that
index is that number, it has overflown.

The patch silenced the warning anyway because the strings could
no longer overlap with the input, but they could still overlap
with other fields.

Fixes: 3e0d5699a975 ("net: stmmac: fix gcc-10 -Wrestrict warning")
Reported-by: Russell King (Oracle) <linux@xxxxxxxxxxxxxxx>
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 640c0ffdff3d..fd4c6517125e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -3502,7 +3502,7 @@ static int stmmac_request_irq_multi_msi(struct net_device *dev)

/* Request Rx MSI irq */
for (i = 0; i < priv->plat->rx_queues_to_use; i++) {
- if (i > MTL_MAX_RX_QUEUES)
+ if (i >= MTL_MAX_RX_QUEUES)
break;
if (priv->rx_irq[i] == 0)
continue;
@@ -3527,7 +3527,7 @@ static int stmmac_request_irq_multi_msi(struct net_device *dev)

/* Request Tx MSI irq */
for (i = 0; i < priv->plat->tx_queues_to_use; i++) {
- if (i > MTL_MAX_TX_QUEUES)
+ if (i >= MTL_MAX_TX_QUEUES)
break;
if (priv->tx_irq[i] == 0)
continue;
--
2.29.2