iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ipvlan: don't deref eth hdr before checking it's set

Browse Source 
[ Upstream commit ad8192767c9f9cf97da57b9ffcea70fb100febef ]

IPvlan in L3 mode discards outbound multicast packets but performs
the check before ensuring the ether-header is set or not. This is
an error that Eric found through code browsing.

Fixes: 2ad7bf363841 (“ipvlan: Initial check-in of the IPVLAN driver.”)
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mahesh Bandewar 2020-03-09 15:56:56 -07:00 committed by Greg Kroah-Hartman
parent 8621153cb6
commit 2ad8246c4d
1 changed files with 10 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
drivers/net/ipvlan/ipvlan_core.c
View File

@ -444,19 +444,21 @@ static int ipvlan_process_outbound(struct sk_buff *skb)
struct ethhdr *ethh = eth_hdr(skb);
int ret = NET_XMIT_DROP;
/* In this mode we dont care about multicast and broadcast traffic */
if (is_multicast_ether_addr(ethh->h_dest)) {
pr_debug_ratelimited("Dropped {multi|broad}cast of type=[%x]\n",
ntohs(skb->protocol));
kfree_skb(skb);
goto out;
}
/* The ipvlan is a pseudo-L2 device, so the packets that we receive
* will have L2; which need to discarded and processed further
* in the net-ns of the main-device.
*/
if (skb_mac_header_was_set(skb)) {
/* In this mode we dont care about
* multicast and broadcast traffic */
if (is_multicast_ether_addr(ethh->h_dest)) {
pr_debug_ratelimited(
"Dropped {multi|broad}cast of type=[%x]\n",
ntohs(skb->protocol));
kfree_skb(skb);
goto out;
}
skb_pull(skb, sizeof(*ethh));
skb->mac_header = (typeof(skb->mac_header))~0U;
skb_reset_network_header(skb);