ICMPv6: treat dest unreachable codes 5 and 6 as EACCES, not EPROTO

[ Upstream commit 61e76b178dbe7145e8d6afa84bb4ccea71918994 ]

RFC 4443 has defined two additional codes for ICMPv6 type 1 (destination
unreachable) messages:
        5 - Source address failed ingress/egress policy
	6 - Reject route to destination

Now they are treated as protocol error and icmpv6_err_convert() converts them
to EPROTO.

RFC 4443 says:
	"Codes 5 and 6 are more informative subsets of code 1."

Treat codes 5 and 6 as code 1 (EACCES)

Btw, connect() returning -EPROTO confuses firefox, so that fallback to
other/IPv4 addresses does not work:
https://bugzilla.mozilla.org/show_bug.cgi?id=910773

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 11 insertions, 1 deletions

diff --git a/include/uapi/linux/icmpv6.h b/include/uapi/linux/icmpv6.h
index e0133c73c304..590beda78ea0 100644
--- a/include/uapi/linux/icmpv6.h
+++ b/include/uapi/linux/icmpv6.h
@@ -115,6 +115,8 @@ struct icmp6hdr {
 #define ICMPV6_NOT_NEIGHBOUR            2
 #define ICMPV6_ADDR_UNREACH             3
 #define ICMPV6_PORT_UNREACH             4
+#define ICMPV6_POLICY_FAIL              5
+#define ICMPV6_REJECT_ROUTE             6
 
 /*
  *      Codes for Time Exceeded
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index b4ff0a42b8c7..70e704d49007 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -931,6 +931,14 @@ static const struct icmp6_err {
                 .err    = ECONNREFUSED,
                 .fatal  = 1,
         },
+        {       /* POLICY_FAIL */
+                .err    = EACCES,
+                .fatal  = 1,
+        },
+        {       /* REJECT_ROUTE */
+                .err    = EACCES,
+                .fatal  = 1,
+        },
 };
 
 int icmpv6_err_convert(u8 type, u8 code, int *err)
@@ -942,7 +950,7 @@ int icmpv6_err_convert(u8 type, u8 code, int *err)
         switch (type) {
         case ICMPV6_DEST_UNREACH:
                 fatal = 1;
-                if (code <= ICMPV6_PORT_UNREACH) {
+                if (code < ARRAY_SIZE(tab_unreach)) {
                         *err  = tab_unreach[code].err;
                         fatal = tab_unreach[code].fatal;
                 }