From 4707893315802a0917231b94cb20cbe50ccbfe03 Mon Sep 17 00:00:00 2001 From: Matt Johnston Date: Tue, 22 Oct 2024 18:25:14 +0800 Subject: [PATCH] mctp i2c: handle NULL header address [ Upstream commit 01e215975fd80af81b5b79f009d49ddd35976c13 ] daddr can be NULL if there is no neighbour table entry present, in that case the tx packet should be dropped. saddr will usually be set by MCTP core, but check for NULL in case a packet is transmitted by a different protocol. Fixes: f5b8abf9fc3d ("mctp i2c: MCTP I2C binding driver") Cc: stable@vger.kernel.org Reported-by: Dung Cao Signed-off-by: Matt Johnston Reviewed-by: Simon Horman Link: https://patch.msgid.link/20241022-mctp-i2c-null-dest-v3-1-e929709956c5@codeconstruct.com.au Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/mctp/mctp-i2c.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/mctp/mctp-i2c.c b/drivers/net/mctp/mctp-i2c.c index 1d67a3ca1fd1..7635a8b3c35c 100644 --- a/drivers/net/mctp/mctp-i2c.c +++ b/drivers/net/mctp/mctp-i2c.c @@ -547,6 +547,9 @@ static int mctp_i2c_header_create(struct sk_buff *skb, struct net_device *dev, if (len > MCTP_I2C_MAXMTU) return -EMSGSIZE; + if (!daddr || !saddr) + return -EINVAL; + lldst = *((u8 *)daddr); llsrc = *((u8 *)saddr);