From: Szymon Heidrich <szymon.heidrich@gmail.com>
Date: Mon, 13 Mar 2023 23:00:45 +0100
Subject: [PATCH] net: usb: smsc75xx: Limit packet length to skb->len
References: bsc#1012628
Patch-mainline: 6.2.8
Git-commit: d8b228318935044dafe3a5bc07ee71a1f1424b8d
[ Upstream commit d8b228318935044dafe3a5bc07ee71a1f1424b8d ]
Packet length retrieved from skb data may be larger than
the actual socket buffer length (up to 9026 bytes). In such
case the cloned skb passed up the network stack will leak
kernel memory contents.
Fixes: d0cad871703b ("smsc75xx: SMSC LAN75xx USB gigabit ethernet adapter driver")
Signed-off-by: Szymon Heidrich <szymon.heidrich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/net/usb/smsc75xx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c
index 95de452f..db34f8d1 100644
--- a/drivers/net/usb/smsc75xx.c
+++ b/drivers/net/usb/smsc75xx.c
@@ -2212,7 +2212,8 @@ static int smsc75xx_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
dev->net->stats.rx_frame_errors++;
} else {
/* MAX_SINGLE_PACKET_SIZE + 4(CRC) + 2(COE) + 4(Vlan) */
- if (unlikely(size > (MAX_SINGLE_PACKET_SIZE + ETH_HLEN + 12))) {
+ if (unlikely(size > (MAX_SINGLE_PACKET_SIZE + ETH_HLEN + 12) ||
+ size > skb->len)) {
netif_dbg(dev, rx_err, dev->net,
"size err rx_cmd_a=0x%08x\n",
rx_cmd_a);
--
2.35.3