| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <E1LCl3n-00052k-6h@gondolin.me.apana.org.au>
Date: Wed, 17 Dec 2008 12:18:47 +1100
From: Herbert Xu <herbert@...dor.apana.org.au>
To: ilpo.jarvinen@...sinki.fi (Ilpo J??rvinen)
Cc: davem@...emloft.net, netdev@...r.kernel.org, ptesarik@...e.cz
Subject: Re: [PATCH] tcp: make urg+gso work for real this time
Ilpo J??rvinen <ilpo.jarvinen@...sinki.fi> wrote:
>
> I should have noticed this earlier... :-) The previous solution
> to URG+GSO/TSO will cause SACK block tcp_fragment to do zig-zig
> patterns, or even worse, a steep downward slope into packet
> counting because each skb pcount would be truncated to pcount
> of 2 and then the following fragments of the later portion would
> restore the window again.
How about just handling it, URG isn't that hard. If anyone is
bored you can do this for GRO as well.
tcp: Add GSO support for urgent data
When segmenting packets with urgent data we need to clear the
urgent flag/pointer once we move past the end of the urgent data.
This was not handled correctly in GSO or (presumably) in existing
hardware.
This patch adds a new GSO flag for TCP urgent data and also fixes
its handling in GSO.
Signed-off-by: Herbert Xu <herbert@...dor.apana.org.au>
Cheers,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index e26f549..4508c48 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -532,9 +532,11 @@ struct net_device
#define NETIF_F_GSO_ROBUST (SKB_GSO_DODGY << NETIF_F_GSO_SHIFT)
#define NETIF_F_TSO_ECN (SKB_GSO_TCP_ECN << NETIF_F_GSO_SHIFT)
#define NETIF_F_TSO6 (SKB_GSO_TCPV6 << NETIF_F_GSO_SHIFT)
+#define NETIF_F_TSO_URG (SKB_GSO_TCP_URG << NETIF_F_GSO_SHIFT)
/* List of features with software fallbacks. */
-#define NETIF_F_GSO_SOFTWARE (NETIF_F_TSO | NETIF_F_TSO_ECN | NETIF_F_TSO6)
+#define NETIF_F_GSO_SOFTWARE (NETIF_F_TSO | NETIF_F_TSO_ECN | \
+ NETIF_F_TSO6 | NETIF_F_TSO_URG)
#define NETIF_F_GEN_CSUM (NETIF_F_NO_CSUM | NETIF_F_HW_CSUM)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 2725f4e..56e9179 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -188,6 +188,9 @@ enum {
SKB_GSO_TCP_ECN = 1 << 3,
SKB_GSO_TCPV6 = 1 << 4,
+
+ /* This indicates the tcp segment has URG set. */
+ SKB_GSO_TCP_URG = 1 << 5,
};
#if BITS_PER_LONG > 32
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 1aa2dc9..33305f6 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1202,6 +1202,7 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
SKB_GSO_UDP |
SKB_GSO_DODGY |
SKB_GSO_TCP_ECN |
+ SKB_GSO_TCP_URG |
0)))
goto out;
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index c5aca0b..e6796a8 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2383,6 +2383,7 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int features)
__be32 delta;
unsigned int oldlen;
unsigned int len;
+ unsigned int urg_ptr;
if (!pskb_may_pull(skb, sizeof(*th)))
goto out;
@@ -2408,6 +2409,7 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int features)
SKB_GSO_DODGY |
SKB_GSO_TCP_ECN |
SKB_GSO_TCPV6 |
+ SKB_GSO_TCP_URG |
0) ||
!(type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))))
goto out;
@@ -2429,6 +2431,7 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int features)
skb = segs;
th = tcp_hdr(skb);
seq = ntohl(th->seq);
+ urg_ptr = th->urg ? ntohs(th->urg_ptr) : 0;
do {
th->fin = th->psh = 0;
@@ -2446,6 +2449,14 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int features)
th->seq = htonl(seq);
th->cwr = 0;
+
+ if (urg_ptr <= len)
+ urg_ptr = 0;
+ else
+ urg_ptr -= len;
+
+ th->urg = !!urg_ptr;
+ th->urg_ptr = htons(urg_ptr);
} while (skb->next);
delta = htonl(oldlen + (skb->tail - skb->transport_header) +
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index fe3b4bd..d4dc0fa 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -667,6 +667,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
between(tp->snd_up, tcb->seq + 1, tcb->seq + 0xFFFF))) {
th->urg_ptr = htons(tp->snd_up - tcb->seq);
th->urg = 1;
+ skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_URG;
}
tcp_options_write((__be32 *)(th + 1), tp, &opts, &md5_hash_location);
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 01edac8..c11d3d9 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -746,6 +746,7 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, int features)
SKB_GSO_DODGY |
SKB_GSO_TCP_ECN |
SKB_GSO_TCPV6 |
+ SKB_GSO_TCP_URG |
0)))
goto out;
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists