[PATCH 5.13 717/800] staging: gdm724x: check for overflow in gdm_lte_netif_rx()
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-07-12 08:53:31
Also in:
lkml
Subsystem:
staging subsystem, the rest · Maintainers:
Greg Kroah-Hartman, Linus Torvalds
From: Dan Carpenter <redacted>
[ 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 <redacted>
Link: https://lore.kernel.org/r/YMcoTPsCYlhh2TQo@mwanda (local)
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