lkml.org 
[lkml]   [2001]   [Apr]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: Kernel Oops when using the Netfilter QUEUE target
On Wed, 25 Apr 2001, Martin Clausen wrote:

> Hi there!
>
> I have encountered a problem (perhaps a bug)! The attached code makes my kernel oops
> in some cases when injecting new packets through Netfilter's QUEUE target. The problem
> only appears when the original packet is a TCP packet; i have tried with ICMP and UDP packets
> also but this does not trigger any oops. I have tried to code on several computers and they
> all oops. The following description regards the case when submitting new packets instead
> of TCP packets.

Please try the patch below.

- James
--
James Morris
<jmorris@intercode.com.au>

diff -urN linux-2.4.3/net/ipv4/netfilter/ip_queue.c linux-2.4.3-fix/net/ipv4/netfilter/ip_queue.c
--- linux-2.4.3/net/ipv4/netfilter/ip_queue.c Tue Dec 12 07:37:04 2000
+++ linux-2.4.3-fix/net/ipv4/netfilter/ip_queue.c Wed Apr 25 16:10:24 2001
@@ -24,8 +24,10 @@
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <net/sock.h>
+#include <net/route.h>

#include <linux/netfilter_ipv4/ip_queue.h>
+#include <linux/netfilter_ipv4/ip_tables.h>

#define IPQ_QMAX_DEFAULT 1024
#define IPQ_PROC_FS_NAME "ip_queue"
@@ -198,6 +200,32 @@
kfree(q);
}

+/* With a chainsaw... */
+static int route_me_harder(struct sk_buff *skb)
+{
+ struct iphdr *iph = skb->nh.iph;
+ struct rtable *rt;
+
+ struct rt_key key = {
+ dst:iph->daddr, src:iph->saddr,
+ oif:skb->sk ? skb->sk->bound_dev_if : 0,
+ tos:RT_TOS(iph->tos)|RTO_CONN,
+#ifdef CONFIG_IP_ROUTE_FWMARK
+ fwmark:skb->nfmark
+#endif
+ };
+
+ if (ip_route_output_key(&rt, &key) != 0) {
+ printk("route_me_harder: No more route.\n");
+ return -EINVAL;
+ }
+
+ /* Drop old route. */
+ dst_release(skb->dst);
+ skb->dst = &rt->u.dst;
+ return 0;
+}
+
static int ipq_mangle_ipv4(ipq_verdict_msg_t *v, ipq_queue_element_t *e)
{
int diff;
@@ -223,6 +251,8 @@
"in mangle, dropping packet\n");
return -ENOMEM;
}
+ if (e->skb->sk)
+ skb_set_owner_w(newskb, e->skb->sk);
kfree_skb(e->skb);
e->skb = newskb;
}
@@ -230,7 +260,13 @@
}
memcpy(e->skb->data, v->payload, v->data_len);
e->skb->nfcache |= NFC_ALTERED;
- return 0;
+
+ /*
+ * Extra routing needed on local out, as the QUEUE target never
+ * returns control to the table.
+ */
+ return ((e->info->hook == NF_IP_LOCAL_OUT) ?
+ route_me_harder(e->skb) : 0);
}

static inline int id_cmp(ipq_queue_element_t *e, unsigned long id)
diff -urN linux-2.4.3/net/ipv4/netfilter/iptable_mangle.c linux-2.4.3-fix/net/ipv4/netfilter/iptable_mangle.c
--- linux-2.4.3/net/ipv4/netfilter/iptable_mangle.c Tue Jan 30 03:07:30 2001
+++ linux-2.4.3-fix/net/ipv4/netfilter/iptable_mangle.c Wed Apr 25 16:09:02 2001
@@ -148,7 +148,7 @@

ret = ipt_do_table(pskb, hook, in, out, &packet_mangler, NULL);
/* Reroute for ANY change. */
- if (ret != NF_DROP && ret != NF_STOLEN
+ if (ret != NF_DROP && ret != NF_STOLEN && ret != NF_QUEUE
&& ((*pskb)->nh.iph->saddr != saddr
|| (*pskb)->nh.iph->daddr != daddr
|| (*pskb)->nfmark != nfmark

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:28    [W:0.061 / U:0.180 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site