fixes for 4.19

[thirdparty/kernel/stable-queue.git] / releases / 4.4.170 / packet-validate-address-length-if-non-zero.patch

From foo@baz Sat Jan  5 08:30:28 CET 2019
From: Willem de Bruijn <willemb@google.com>
Date: Sat, 22 Dec 2018 16:53:45 -0500
Subject: packet: validate address length if non-zero

From: Willem de Bruijn <willemb@google.com>

[ Upstream commit 6b8d95f1795c42161dc0984b6863e95d6acf24ed ]

Validate packet socket address length if a length is given. Zero
length is equivalent to not setting an address.

Fixes: 99137b7888f4 ("packet: validate address length")
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/packet/af_packet.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -2511,7 +2511,7 @@ static int tpacket_snd(struct packet_soc
 						sll_addr)))
 			goto out;
 		proto	= saddr->sll_protocol;
-		addr	= saddr->sll_addr;
+		addr	= saddr->sll_halen ? saddr->sll_addr : NULL;
 		dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
 		if (addr && dev && saddr->sll_halen < dev->addr_len)
 			goto out;
@@ -2680,7 +2680,7 @@ static int packet_snd(struct socket *soc
 		if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
 			goto out;
 		proto	= saddr->sll_protocol;
-		addr	= saddr->sll_addr;
+		addr	= saddr->sll_halen ? saddr->sll_addr : NULL;
 		dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
 		if (addr && dev && saddr->sll_halen < dev->addr_len)
 			goto out;