From mboxrd@z Thu Jan 1 00:00:00 1970 From: YOSHIFUJI Hideaki / =?iso-2022-jp?B?GyRCNUhGIzFRTEAbKEI=?= Subject: [PATCH] Ensure to use icmpv6_socket in non-preemptive context. Date: Sun, 12 Jun 2005 23:03:58 +0900 (JST) Message-ID: <20050612.230358.119812619.yoshfuji@linux-ipv6.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: yoshfuji@linux-ipv6.org, netdev@oss.sgi.com Return-path: To: davem@davemloft.net Sender: netdev-bounce@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org Hello. [IPV6] Make sure to use icmpv6_socket in non-preemptive context. We saw following trace several times: |BUG: using smp_processor_id() in preemptible [00000001] code: httpd/30137 |caller is icmpv6_send+0x23/0x540 | [] smp_processor_id+0x9b/0xb8 | [] icmpv6_send+0x23/0x540 This is because of icmpv6_socket, which is the only one user of smp_processor_id() in icmpv6_send(), AFAIK. Since it should be used in non-preemptive context, let's defer the dereference after disabling preemption (by icmpv6_xmit_lock()). Signed-off-by: YOSHIFUJI Hideaki diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c --- a/net/ipv6/icmp.c +++ b/net/ipv6/icmp.c @@ -277,8 +277,8 @@ void icmpv6_send(struct sk_buff *skb, in { struct inet6_dev *idev = NULL; struct ipv6hdr *hdr = skb->nh.ipv6h; - struct sock *sk = icmpv6_socket->sk; - struct ipv6_pinfo *np = inet6_sk(sk); + struct sock *sk; + struct ipv6_pinfo *np; struct in6_addr *saddr = NULL; struct dst_entry *dst; struct icmp6hdr tmp_hdr; @@ -358,6 +358,9 @@ void icmpv6_send(struct sk_buff *skb, in if (icmpv6_xmit_lock()) return; + sk = icmpv6_socket->sk; + np = inet6_sk(sk); + if (!icmpv6_xrlim_allow(sk, type, &fl)) goto out; @@ -423,9 +426,9 @@ out: static void icmpv6_echo_reply(struct sk_buff *skb) { - struct sock *sk = icmpv6_socket->sk; + struct sock *sk; struct inet6_dev *idev; - struct ipv6_pinfo *np = inet6_sk(sk); + struct ipv6_pinfo *np; struct in6_addr *saddr = NULL; struct icmp6hdr *icmph = (struct icmp6hdr *) skb->h.raw; struct icmp6hdr tmp_hdr; @@ -454,6 +457,9 @@ static void icmpv6_echo_reply(struct sk_ if (icmpv6_xmit_lock()) return; + sk = icmpv6_socket->sk; + np = inet6_sk(sk); + if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst)) fl.oif = np->mcast_oif; -- YOSHIFUJI Hideaki @ USAGI Project GPG-FP : 9022 65EB 1ECF 3AD1 0BDF 80D8 4807 F894 E062 0EEA