ipv6 RAW: Disallow IPPROTO_IPV6-level IPV6_CHECKSUM socket option on ICMPv6 sockets.
RFC3542 tells that IPV6_CHECKSUM socket option in the IPPROTO_IPV6
level is not allowed on ICMPv6 sockets. IPPROTO_RAW level
IPV6_CHECKSUM socket option (a Linux extension) is still allowed.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 6193b12..396f0ea 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -971,6 +971,19 @@
switch (optname) {
case IPV6_CHECKSUM:
+ if (inet_sk(sk)->num == IPPROTO_ICMPV6 &&
+ level == IPPROTO_IPV6) {
+ /*
+ * RFC3542 tells that IPV6_CHECKSUM socket
+ * option in the IPPROTO_IPV6 level is not
+ * allowed on ICMPv6 sockets.
+ * If you want to set it, use IPPROTO_RAW
+ * level IPV6_CHECKSUM socket option
+ * (Linux extension).
+ */
+ return -EINVAL;
+ }
+
/* You may get strange result with a positive odd offset;
RFC2292bis agrees with me. */
if (val > 0 && (val&1))
@@ -1046,6 +1059,11 @@
switch (optname) {
case IPV6_CHECKSUM:
+ /*
+ * We allow getsockopt() for IPPROTO_IPV6-level
+ * IPV6_CHECKSUM socket option on ICMPv6 sockets
+ * since RFC3542 is silent about it.
+ */
if (rp->checksum == 0)
val = -1;
else