From b0dd663b60944a3ce86430fa35549fb37968bda0 Mon Sep 17 00:00:00 2001 From: Sonic Zhang Date: Wed, 11 Sep 2013 11:31:53 +0800 Subject: netpoll: Should handle ETH_P_ARP other than ETH_P_IP in netpoll_neigh_reply The received ARP request type in the Ethernet packet head is ETH_P_ARP other than ETH_P_IP. [ Bug introduced by commit b7394d2429c198b1da3d46ac39192e891029ec0f ("netpoll: prepare for ipv6") ] Signed-off-by: Sonic Zhang Signed-off-by: David S. Miller --- net/core/netpoll.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core/netpoll.c') diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 2c637e9a0b27..c3c7b27c112d 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -550,7 +550,7 @@ static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo return; proto = ntohs(eth_hdr(skb)->h_proto); - if (proto == ETH_P_IP) { + if (proto == ETH_P_ARP) { struct arphdr *arp; unsigned char *arp_ptr; /* No arp on this interface */ -- cgit v1.2.2 From d0fe8c888b1fd1a2f84b9962cabcb98a70988aec Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Thu, 19 Sep 2013 15:02:35 +0200 Subject: netpoll: fix NULL pointer dereference in netpoll_cleanup I've been hitting a NULL ptr deref while using netconsole because the np->dev check and the pointer manipulation in netpoll_cleanup are done without rtnl and the following sequence happens when having a netconsole over a vlan and we remove the vlan while disabling the netconsole: CPU 1 CPU2 removes vlan and calls the notifier enters store_enabled(), calls netdev_cleanup which checks np->dev and then waits for rtnl executes the netconsole netdev release notifier making np->dev == NULL and releases rtnl continues to dereference a member of np->dev which at this point is == NULL Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- net/core/netpoll.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'net/core/netpoll.c') diff --git a/net/core/netpoll.c b/net/core/netpoll.c index c3c7b27c112d..fc75c9e461b8 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -1284,15 +1284,14 @@ EXPORT_SYMBOL_GPL(__netpoll_free_async); void netpoll_cleanup(struct netpoll *np) { - if (!np->dev) - return; - rtnl_lock(); + if (!np->dev) + goto out; __netpoll_cleanup(np); - rtnl_unlock(); - dev_put(np->dev); np->dev = NULL; +out: + rtnl_unlock(); } EXPORT_SYMBOL(netpoll_cleanup); -- cgit v1.2.2