[RFC][PATCH] IPv6:Remove options header when setsockopt's optlen is 0

[RFC][PATCH] IPv6:Remove options header when setsockopt's optlen is 0

[Shan Wei]

Remove the sticky Hop-by-Hop options header by calling setsockopt() for IPV6_HOPOPTS
with a zero option length, per RFC3542.

Routing header and Destination options header does the same as Hop-by-Hop options header. 


Signed-off-by: Shan Wei<shanwei@cn.fujitsu.com>
---
 net/ipv6/ipv6_sockglue.c |   11 +++++++----
 1 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index c042ce1..86e28a7 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -345,18 +345,21 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 	case IPV6_DSTOPTS:
 	{
 		struct ipv6_txoptions *opt;
+
+		/* remove any sticky options header with a zero option
+		 * length, per RFC3542.
+		 */
 		if (optlen == 0)
 			optval = NULL;
+		else if (optlen < sizeof(struct ipv6_opt_hdr) ||
+			 optlen & 0x7 || optlen > 8 * 255)
+			goto e_inval;
 
 		/* hop-by-hop / destination options are privileged option */
 		retv = -EPERM;
 		if (optname != IPV6_RTHDR && !capable(CAP_NET_RAW))
 			break;
 
-		if (optlen < sizeof(struct ipv6_opt_hdr) ||
-		    optlen & 0x7 || optlen > 8 * 255)
-			goto e_inval;
-
 		opt = ipv6_renew_options(sk, np->opt, optname,
 					 (struct ipv6_opt_hdr __user *)optval,
 					 optlen);

Re: [RFC][PATCH] IPv6:Remove options header when setsockopt's optlen is 0

[YOSHIFUJI Hideaki / 吉藤英明]

In article <4858AE3D.6070101@cn.fujitsu.com> (at Wed, 18 Jun 2008 14:42:05 +0800), Shan Wei <shanwei@cn.fujitsu.com> says:

> Remove the sticky Hop-by-Hop options header by calling setsockopt() for IPV6_HOPOPTS
> with a zero option length, per RFC3542.
> 
> Routing header and Destination options header does the same as Hop-by-Hop options header. 
> 
> 
> Signed-off-by: Shan Wei<shanwei@cn.fujitsu.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

--yoshfuji

Re: [RFC][PATCH] IPv6:Remove options header when setsockopt's optlen is 0

[David Miller]

From: YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@linux-ipv6.org>
Date: Thu, 19 Jun 2008 16:52:18 +0900 (JST)

> In article <4858AE3D.6070101@cn.fujitsu.com> (at Wed, 18 Jun 2008 14:42:05 +0800), Shan Wei <shanwei@cn.fujitsu.com> says:
> 
> > Remove the sticky Hop-by-Hop options header by calling setsockopt() for IPV6_HOPOPTS
> > with a zero option length, per RFC3542.
> > 
> > Routing header and Destination options header does the same as Hop-by-Hop options header. 
> > 
> > 
> > Signed-off-by: Shan Wei<shanwei@cn.fujitsu.com>
> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

Applied to net-2.6, thanks!