From: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Date: Fri, 9 Mar 2007 04:48:23 +0000 (-0800)
Subject: [IPV6]: Ensure to truncate result and return full length for sticky options.
X-Git-Tag: firefly_0821_release~30278^2~370
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e5268f12f26f1f51590cd1ed26547e21c46b08f2;p=firefly-linux-kernel-4.4.55.git

[IPV6]: Ensure to truncate result and return full length for sticky options.

Bug noticed by Chris Wright <chrisw@sous-sol.org>.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index eceed09e434d..1d56b465bddb 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -825,9 +825,9 @@ static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
 		return 0;
 
 	len = min_t(unsigned int, len, ipv6_optlen(hdr));
-	if (copy_to_user(optval, hdr, ipv6_optlen(hdr)))
+	if (copy_to_user(optval, hdr, len));
 		return -EFAULT;
-	return len;
+	return ipv6_optlen(hdr);
 }
 
 static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,