4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Willem de Bruijn <willemb@xxxxxxxxxx>
[ 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@xxxxxxxxxx>
Signed-off-by: Willem de Bruijn <willemb@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
@@ -2625,7 +2625,7 @@ 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;
@@ -2825,7 +2825,7 @@ 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;
