From 1162563f82b434e3099c9e6c1bbdba846d792f0d Mon Sep 17 00:00:00 2001
From: Jiri Pirko <jpirko@redhat.com>
Date: Tue, 2 Mar 2010 20:40:01 +0000
Subject: [PATCH] af_packet: move strict addr_len check right before
dev_[mc/unicast]_[add/del]
My previous patch 914c8ad2d18b62ad1420f518c0cab0b0b90ab308 incorrectly changed
the length check in packet_mc_add to be more strict. The problem is that
userspace is not filling this field (and it stays zeroed) in case of setting
PACKET_MR_PROMISC or PACKET_MR_ALLMULTI. So move the strict check to the point
in path where the addr_len must be set correctly.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Reported-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/packet/af_packet.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 031a5e6fb4aa..1612d417d10c 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1688,6 +1688,8 @@ static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
{
switch (i->type) {
case PACKET_MR_MULTICAST:
+ if (i->alen != dev->addr_len)
+ return -EINVAL;
if (what > 0)
return dev_mc_add(dev, i->addr, i->alen, 0);
else
@@ -1700,6 +1702,8 @@ static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
return dev_set_allmulti(dev, what);
break;
case PACKET_MR_UNICAST:
+ if (i->alen != dev->addr_len)
+ return -EINVAL;
if (what > 0)
return dev_unicast_add(dev, i->addr);
else
@@ -1734,7 +1738,7 @@ static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
goto done;
err = -EINVAL;
- if (mreq->mr_alen != dev->addr_len)
+ if (mreq->mr_alen > dev->addr_len)
goto done;
err = -ENOBUFS;
--
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