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

From: Herton Ronaldo Krzesinski
Date: Tue Feb 19 2013 - 13:52:52 EST


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

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

From: Cong Wang <xiyou.wangcong@xxxxxxxxx>

commit c9be4a5c49cf51cc70a993f004c5bb30067a65ce upstream.

A regression is introduced by the following commit:

commit 4d52cfbef6266092d535237ba5a4b981458ab171
Author: Eric Dumazet <eric.dumazet@xxxxxxxxx>
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@xxxxxxxxx>
Cc: nitin padalia <padalia.nitin@xxxxxxxxx>
Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Acked-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@xxxxxxxxxxxxx>
---
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

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