From: Eric Dumazet <[email protected]> On Sun, 2012-09-02 at 15:28 +0200, Florian Westphal wrote: > Sami Farin <[email protected]> wrote: > > I get this panic every 1-2 days. > > Also with 7a611e69b26069a511d9d5251c6a28af6c521121 (commit before > > 3.6.0-rc4). > > Could you please post iptables-save output? > My guess is you're using NFLOG in INPUT? > > If so, I bet its caused by the tcp early demux stuff. > Does that crash go away with ip_early_demux sysctl off? > > My guess is its assigning skb->sk with TIMEWAIT sockets, which > would explain the crash.
Yes thats probably the reason. First I thought changing demux to not do the lookup of TIMEWAIT slot in __inet_lookup_established(), then it sounds not optimal to redo the full lookup for ESTABLISHED sockets later in TCP stack. So it seems we should fix xt_LOG instead Thanks Florian ! [PATCH] xt_LOG: take care of timewait sockets Sami Farin reported crashes in xt_LOG because it assumes skb->sk is a full blown socket. But with TCP early demux, we can have skb->sk pointing to a timewait socket. Diagnosed-by: Florian Westphal <[email protected]> Reported-by: Sami Farin <[email protected]> Signed-off-by: Eric Dumazet <[email protected]> --- net/netfilter/xt_LOG.c | 33 +++++++++++++++++---------------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/net/netfilter/xt_LOG.c b/net/netfilter/xt_LOG.c index ff5f75f..2a4f969 100644 --- a/net/netfilter/xt_LOG.c +++ b/net/netfilter/xt_LOG.c @@ -145,6 +145,19 @@ static int dump_tcp_header(struct sbuff *m, const struct sk_buff *skb, return 0; } +static void dump_sk_uid_gid(struct sbuff *m, struct sock *sk) +{ + if (!sk || sk->sk_state == TCP_TIME_WAIT) + return; + + read_lock_bh(&sk->sk_callback_lock); + if (sk->sk_socket && sk->sk_socket->file) + sb_add(m, "UID=%u GID=%u ", + sk->sk_socket->file->f_cred->fsuid, + sk->sk_socket->file->f_cred->fsgid); + read_unlock_bh(&sk->sk_callback_lock); +} + /* One level of recursion won't kill us */ static void dump_ipv4_packet(struct sbuff *m, const struct nf_loginfo *info, @@ -361,14 +374,8 @@ static void dump_ipv4_packet(struct sbuff *m, } /* Max length: 15 "UID=4294967295 " */ - if ((logflags & XT_LOG_UID) && !iphoff && skb->sk) { - read_lock_bh(&skb->sk->sk_callback_lock); - if (skb->sk->sk_socket && skb->sk->sk_socket->file) - sb_add(m, "UID=%u GID=%u ", - skb->sk->sk_socket->file->f_cred->fsuid, - skb->sk->sk_socket->file->f_cred->fsgid); - read_unlock_bh(&skb->sk->sk_callback_lock); - } + if ((logflags & XT_LOG_UID) && !iphoff) + dump_sk_uid_gid(m, skb->sk); /* Max length: 16 "MARK=0xFFFFFFFF " */ if (!iphoff && skb->mark) @@ -717,14 +724,8 @@ static void dump_ipv6_packet(struct sbuff *m, } /* Max length: 15 "UID=4294967295 " */ - if ((logflags & XT_LOG_UID) && recurse && skb->sk) { - read_lock_bh(&skb->sk->sk_callback_lock); - if (skb->sk->sk_socket && skb->sk->sk_socket->file) - sb_add(m, "UID=%u GID=%u ", - skb->sk->sk_socket->file->f_cred->fsuid, - skb->sk->sk_socket->file->f_cred->fsgid); - read_unlock_bh(&skb->sk->sk_callback_lock); - } + if ((logflags & XT_LOG_UID) && recurse) + dump_sk_uid_gid(m, skb->sk); /* Max length: 16 "MARK=0xFFFFFFFF " */ if (!recurse && skb->mark) ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ E1000-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/e1000-devel To learn more about Intel® Ethernet, visit http://communities.intel.com/community/wired
