From 8cdb46da06ea94543a3b2e53e3e92736421d1093 Mon Sep 17 00:00:00 2001 From: Hans Schillstrom Date: Wed, 15 May 2013 01:23:45 +0000 Subject: netfilter: log: netns NULL ptr bug when calling from conntrack Since (69b34fb netfilter: xt_LOG: add net namespace support for xt_LOG), we hit this: [ 4224.708977] BUG: unable to handle kernel NULL pointer dereference at 0000000000000388 [ 4224.709074] IP: [] ipt_log_packet+0x29/0x270 when callling log functions from conntrack both in and out are NULL i.e. the net pointer is invalid. Adding struct net *net in call to nf_logfn() will secure that there always is a vaild net ptr. Reported as netfilter's bugzilla bug 818: https://bugzilla.netfilter.org/show_bug.cgi?id=818 Reported-by: Ronald Signed-off-by: Hans Schillstrom Signed-off-by: Pablo Neira Ayuso --- net/ipv4/netfilter/ipt_ULOG.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'net/ipv4') diff --git a/net/ipv4/netfilter/ipt_ULOG.c b/net/ipv4/netfilter/ipt_ULOG.c index f8a222cb..cf08218 100644 --- a/net/ipv4/netfilter/ipt_ULOG.c +++ b/net/ipv4/netfilter/ipt_ULOG.c @@ -162,7 +162,8 @@ static struct sk_buff *ulog_alloc_skb(unsigned int size) return skb; } -static void ipt_ulog_packet(unsigned int hooknum, +static void ipt_ulog_packet(struct net *net, + unsigned int hooknum, const struct sk_buff *skb, const struct net_device *in, const struct net_device *out, @@ -174,7 +175,6 @@ static void ipt_ulog_packet(unsigned int hooknum, size_t size, copy_len; struct nlmsghdr *nlh; struct timeval tv; - struct net *net = dev_net(in ? in : out); struct ulog_net *ulog = ulog_pernet(net); /* ffs == find first bit set, necessary because userspace @@ -291,12 +291,15 @@ alloc_failure: static unsigned int ulog_tg(struct sk_buff *skb, const struct xt_action_param *par) { - ipt_ulog_packet(par->hooknum, skb, par->in, par->out, + struct net *net = dev_net(par->in ? par->in : par->out); + + ipt_ulog_packet(net, par->hooknum, skb, par->in, par->out, par->targinfo, NULL); return XT_CONTINUE; } -static void ipt_logfn(u_int8_t pf, +static void ipt_logfn(struct net *net, + u_int8_t pf, unsigned int hooknum, const struct sk_buff *skb, const struct net_device *in, @@ -318,7 +321,7 @@ static void ipt_logfn(u_int8_t pf, strlcpy(loginfo.prefix, prefix, sizeof(loginfo.prefix)); } - ipt_ulog_packet(hooknum, skb, in, out, &loginfo, prefix); + ipt_ulog_packet(net, hooknum, skb, in, out, &loginfo, prefix); } static int ulog_tg_check(const struct xt_tgchk_param *par) -- cgit v1.1