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netfilter: fix crashes in bridge netfilter caused by fragment jumps
commit 8fa9ff6849 upstream.
When fragments from bridge netfilter are passed to IPv4 or IPv6 conntrack
and a reassembly queue with the same fragment key already exists from
reassembling a similar packet received on a different device (f.i. with
multicasted fragments), the reassembled packet might continue on a different
codepath than where the head fragment originated. This can cause crashes
in bridge netfilter when a fragment received on a non-bridge device (and
thus with skb->nf_bridge == NULL) continues through the bridge netfilter
code.
Add a new reassembly identifier for packets originating from bridge
netfilter and use it to put those packets in insolated queues.
Fixes http://bugzilla.kernel.org/show_bug.cgi?id=14805
Reported-and-Tested-by: Chong Qiao <qiaochong@loongson.cn>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
committed by
Greg Kroah-Hartman
parent
89cf4f4c85
commit
048a424c28
@@ -342,6 +342,7 @@ enum ip_defrag_users
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IP_DEFRAG_CALL_RA_CHAIN,
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IP_DEFRAG_CONNTRACK_IN,
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IP_DEFRAG_CONNTRACK_OUT,
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IP_DEFRAG_CONNTRACK_BRIDGE_IN,
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IP_DEFRAG_VS_IN,
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IP_DEFRAG_VS_OUT,
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IP_DEFRAG_VS_FWD
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@@ -358,6 +358,7 @@ enum ip6_defrag_users {
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IP6_DEFRAG_LOCAL_DELIVER,
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IP6_DEFRAG_CONNTRACK_IN,
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IP6_DEFRAG_CONNTRACK_OUT,
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IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
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};
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struct ip6_create_arg {
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@@ -14,6 +14,7 @@
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#include <net/route.h>
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#include <net/ip.h>
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#include <linux/netfilter_bridge.h>
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#include <linux/netfilter_ipv4.h>
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#include <net/netfilter/ipv4/nf_defrag_ipv4.h>
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@@ -34,6 +35,20 @@ static int nf_ct_ipv4_gather_frags(struct sk_buff *skb, u_int32_t user)
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return err;
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}
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static enum ip_defrag_users nf_ct_defrag_user(unsigned int hooknum,
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struct sk_buff *skb)
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{
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#ifdef CONFIG_BRIDGE_NETFILTER
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if (skb->nf_bridge &&
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skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)
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return IP_DEFRAG_CONNTRACK_BRIDGE_IN;
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#endif
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if (hooknum == NF_INET_PRE_ROUTING)
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return IP_DEFRAG_CONNTRACK_IN;
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else
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return IP_DEFRAG_CONNTRACK_OUT;
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}
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static unsigned int ipv4_conntrack_defrag(unsigned int hooknum,
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struct sk_buff *skb,
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const struct net_device *in,
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@@ -50,10 +65,8 @@ static unsigned int ipv4_conntrack_defrag(unsigned int hooknum,
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#endif
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/* Gather fragments. */
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if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
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if (nf_ct_ipv4_gather_frags(skb,
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hooknum == NF_INET_PRE_ROUTING ?
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IP_DEFRAG_CONNTRACK_IN :
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IP_DEFRAG_CONNTRACK_OUT))
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enum ip_defrag_users user = nf_ct_defrag_user(hooknum, skb);
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if (nf_ct_ipv4_gather_frags(skb, user))
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return NF_STOLEN;
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}
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return NF_ACCEPT;
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@@ -20,6 +20,7 @@
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#include <net/ipv6.h>
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#include <net/inet_frag.h>
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#include <linux/netfilter_bridge.h>
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#include <linux/netfilter_ipv6.h>
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#include <net/netfilter/nf_conntrack.h>
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#include <net/netfilter/nf_conntrack_helper.h>
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@@ -190,6 +191,11 @@ out:
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static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum,
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struct sk_buff *skb)
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{
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#ifdef CONFIG_BRIDGE_NETFILTER
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if (skb->nf_bridge &&
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skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)
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return IP6_DEFRAG_CONNTRACK_BRIDGE_IN;
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#endif
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if (hooknum == NF_INET_PRE_ROUTING)
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return IP6_DEFRAG_CONNTRACK_IN;
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else
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