From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cong Wang Subject: [Patch] arp: fix a regression in arp_solicit() Date: Sun, 23 Dec 2012 22:42:58 +0800 Message-ID: <1356273778-19113-1-git-send-email-xiyou.wangcong@gmail.com> Cc: Sedat Dilek , Eric Dumazet , "David S. Miller" , Julian Anastasov , Cong Wang To: netdev@vger.kernel.org Return-path: Received: from mail-da0-f50.google.com ([209.85.210.50]:65040 "EHLO mail-da0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750947Ab2LWOvD (ORCPT ); Sun, 23 Dec 2012 09:51:03 -0500 Received: by mail-da0-f50.google.com with SMTP id h15so2823209dan.23 for ; Sun, 23 Dec 2012 06:51:03 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: From: Cong Wang Sedat reported the following commit caused a regression: commit 9650388b5c56578fdccc79c57a8c82fb92b8e7f1 Author: Eric Dumazet Date: Fri Dec 21 07:32:10 2012 +0000 ipv4: arp: fix a lockdep splat in arp_solicit This is due to the 6th parameter of arp_send() needs to be NULL for broatcase case, the above commit changed it to all-zero non-NULL hw addr. Reported-by: Sedat Dilek Tested-by: Sedat Dilek Cc: Sedat Dilek Cc: Eric Dumazet Cc: David S. Miller Cc: Julian Anastasov Signed-off-by: Cong Wang --- diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index 1169ed4..9547a273 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -321,7 +321,7 @@ static void arp_error_report(struct neighbour *neigh, struct sk_buff *skb) static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb) { __be32 saddr = 0; - u8 dst_ha[MAX_ADDR_LEN]; + u8 dst_ha[MAX_ADDR_LEN], *dst_hw = NULL; struct net_device *dev = neigh->dev; __be32 target = *(__be32 *)neigh->primary_key; int probes = atomic_read(&neigh->probes); @@ -364,8 +364,8 @@ static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb) if (!(neigh->nud_state & NUD_VALID)) pr_debug("trying to ucast probe in NUD_INVALID\n"); neigh_ha_snapshot(dst_ha, neigh, dev); + dst_hw = dst_ha; } else { - memset(dst_ha, 0, dev->addr_len); probes -= neigh->parms->app_probes; if (probes < 0) { #ifdef CONFIG_ARPD @@ -376,7 +376,7 @@ static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb) } arp_send(ARPOP_REQUEST, ETH_P_ARP, target, dev, saddr, - dst_ha, dev->dev_addr, NULL); + dst_hw, dev->dev_addr, NULL); } static int arp_ignore(struct in_device *in_dev, __be32 sip, __be32 tip)