From d1208f70738c91f13b4eadb1b7a694082e439da2 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 11 Dec 2008 17:56:44 -0500 Subject: [PATCH] NLM: nlm_privileged_requester() doesn't recognize mapped loopback address Commit b85e4676 added the nlm_privileged_requester() helper to check whether an RPC request was sent from a local privileged caller. It recognizes IPv4 privileged callers (from "127.0.0.1"), and IPv6 privileged callers (from "::1"). However, IPV6_ADDR_LOOPBACK is not set for the mapped IPv4 loopback address (::ffff:7f00:0001), so the test breaks when the kernel's RPC service is IPv6-enabled but user space is calling via the IPv4 loopback address. This is actually the most common case for IPv6- enabled RPC services on Linux. Rewrite the IPv6 check to handle the mapped IPv4 loopback address as well as a normal IPv6 loopback address. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- include/linux/lockd/lockd.h | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h index 6ab0449bc82..80d7e8a8257 100644 --- a/include/linux/lockd/lockd.h +++ b/include/linux/lockd/lockd.h @@ -299,8 +299,14 @@ static inline int __nlm_privileged_request4(const struct sockaddr *sap) static inline int __nlm_privileged_request6(const struct sockaddr *sap) { const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; - return (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LOOPBACK) && - (ntohs(sin6->sin6_port) < 1024); + + if (ntohs(sin6->sin6_port) > 1023) + return 0; + + if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_MAPPED) + return ipv4_is_loopback(sin6->sin6_addr.s6_addr32[3]); + + return ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LOOPBACK; } #else /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */ static inline int __nlm_privileged_request6(const struct sockaddr *sap) -- 2.41.1