[PATCH 43/81] net: prevent setting ttl=0 via IP_TTL

[Herton Ronaldo Krzesinski]

3.5.7.6 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Cong Wang <xiyou.wangcong at gmail.com>

commit c9be4a5c49cf51cc70a993f004c5bb30067a65ce upstream.

A regression is introduced by the following commit:

	commit 4d52cfbef6266092d535237ba5a4b981458ab171
	Author: Eric Dumazet <eric.dumazet at gmail.com>
	Date:   Tue Jun 2 00:42:16 2009 -0700

	    net: ipv4/ip_sockglue.c cleanups

	    Pure cleanups

but it is not a pure cleanup...

	-               if (val != -1 && (val < 1 || val>255))
	+               if (val != -1 && (val < 0 || val > 255))

Since there is no reason provided to allow ttl=0, change it back.

Reported-by: nitin padalia <padalia.nitin at gmail.com>
Cc: nitin padalia <padalia.nitin at gmail.com>
Cc: Eric Dumazet <eric.dumazet at gmail.com>
Cc: David S. Miller <davem at davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong at gmail.com>
Acked-by: Eric Dumazet <edumazet at google.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 net/ipv4/ip_sockglue.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 8285f00..aabeb7b 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -589,7 +589,7 @@ static int do_ip_setsockopt(struct sock *sk, int level,
 	case IP_TTL:
 		if (optlen < 1)
 			goto e_inval;
-		if (val != -1 && (val < 0 || val > 255))
+		if (val != -1 && (val < 1 || val > 255))
 			goto e_inval;
 		inet->uc_ttl = val;
 		break;
-- 
1.7.9.5