[PATCH AUTOSEL 4.9 7/8] net: tulip: de4x5: fix the problem that the array 'lp->phy[8]' may be out of bound

From: Sasha Levin
Date: Thu Nov 25 2021 - 21:46:46 EST


From: zhangyue <zhangyue1@xxxxxxxxxx>

[ Upstream commit 61217be886b5f7402843677e4be7e7e83de9cb41 ]

In line 5001, if all id in the array 'lp->phy[8]' is not 0, when the
'for' end, the 'k' is 8.

At this time, the array 'lp->phy[8]' may be out of bound.

Signed-off-by: zhangyue <zhangyue1@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/dec/tulip/de4x5.c | 30 +++++++++++++++-----------
1 file changed, 17 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/dec/tulip/de4x5.c b/drivers/net/ethernet/dec/tulip/de4x5.c
index 005c79b5b3f01..b39e8315e4e27 100644
--- a/drivers/net/ethernet/dec/tulip/de4x5.c
+++ b/drivers/net/ethernet/dec/tulip/de4x5.c
@@ -4995,19 +4995,23 @@ mii_get_phy(struct net_device *dev)
}
if ((j == limit) && (i < DE4X5_MAX_MII)) {
for (k=0; k < DE4X5_MAX_PHY && lp->phy[k].id; k++);
- lp->phy[k].addr = i;
- lp->phy[k].id = id;
- lp->phy[k].spd.reg = GENERIC_REG; /* ANLPA register */
- lp->phy[k].spd.mask = GENERIC_MASK; /* 100Mb/s technologies */
- lp->phy[k].spd.value = GENERIC_VALUE; /* TX & T4, H/F Duplex */
- lp->mii_cnt++;
- lp->active++;
- printk("%s: Using generic MII device control. If the board doesn't operate,\nplease mail the following dump to the author:\n", dev->name);
- j = de4x5_debug;
- de4x5_debug |= DEBUG_MII;
- de4x5_dbg_mii(dev, k);
- de4x5_debug = j;
- printk("\n");
+ if (k < DE4X5_MAX_PHY) {
+ lp->phy[k].addr = i;
+ lp->phy[k].id = id;
+ lp->phy[k].spd.reg = GENERIC_REG; /* ANLPA register */
+ lp->phy[k].spd.mask = GENERIC_MASK; /* 100Mb/s technologies */
+ lp->phy[k].spd.value = GENERIC_VALUE; /* TX & T4, H/F Duplex */
+ lp->mii_cnt++;
+ lp->active++;
+ printk("%s: Using generic MII device control. If the board doesn't operate,\nplease mail the following dump to the author:\n", dev->name);
+ j = de4x5_debug;
+ de4x5_debug |= DEBUG_MII;
+ de4x5_dbg_mii(dev, k);
+ de4x5_debug = j;
+ printk("\n");
+ } else {
+ goto purgatory;
+ }
}
}
purgatory:
--
2.33.0