| From c87bf26fd33f86aed5daf23995cab7220c136f78 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 14 Jun 2021 12:58:36 +0300 |
| Subject: staging: gdm724x: check for overflow in gdm_lte_netif_rx() |
| |
| From: Dan Carpenter <dan.carpenter@oracle.com> |
| |
| [ Upstream commit 7002b526f4ff1f6da34356e67085caafa6be383a ] |
| |
| This code assumes that "len" is at least 62 bytes, but we need a check |
| to prevent a read overflow. |
| |
| Fixes: 61e121047645 ("staging: gdm7240: adding LTE USB driver") |
| Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> |
| Link: https://lore.kernel.org/r/YMcoTPsCYlhh2TQo@mwanda |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/staging/gdm724x/gdm_lte.c | 10 ++++++---- |
| 1 file changed, 6 insertions(+), 4 deletions(-) |
| |
| diff --git a/drivers/staging/gdm724x/gdm_lte.c b/drivers/staging/gdm724x/gdm_lte.c |
| index a41af7aa74ec..bd5f87433404 100644 |
| --- a/drivers/staging/gdm724x/gdm_lte.c |
| +++ b/drivers/staging/gdm724x/gdm_lte.c |
| @@ -611,10 +611,12 @@ static void gdm_lte_netif_rx(struct net_device *dev, char *buf, |
| * bytes (99,130,83,99 dec) |
| */ |
| } __packed; |
| - void *addr = buf + sizeof(struct iphdr) + |
| - sizeof(struct udphdr) + |
| - offsetof(struct dhcp_packet, chaddr); |
| - ether_addr_copy(nic->dest_mac_addr, addr); |
| + int offset = sizeof(struct iphdr) + |
| + sizeof(struct udphdr) + |
| + offsetof(struct dhcp_packet, chaddr); |
| + if (offset + ETH_ALEN > len) |
| + return; |
| + ether_addr_copy(nic->dest_mac_addr, buf + offset); |
| } |
| } |
| |
| -- |
| 2.30.2 |
| |