From 776bd5c7a207de546918f805090bfc823d2660c8 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 18 Mar 2009 20:45:28 -0400 Subject: [PATCH] SUNRPC: Don't flag empty RPCB_GETADDR reply as bogus In 2007, commit e65fe3976f594603ed7b1b4a99d3e9b867f573ea added additional sanity checking to rpcb_decode_getaddr() to make sure we were getting a reply that was long enough to be an actual universal address. If the uaddr string isn't long enough, the XDR decoder returns EIO. However, an empty string is a valid RPCB_GETADDR response if the requested service isn't registered. Moreover, "::.n.m" is also a valid RPCB_GETADDR response for IPv6 addresses that is shorter than rpcb_decode_getaddr()'s lower limit of 11. So this sanity check introduced a regression for rpcbind requests against IPv6 remotes. So revert the lower bound check added by commit e65fe3976f594603ed7b1b4a99d3e9b867f573ea, and add an explicit check for an empty uaddr string, similar to libtirpc's rpcb_getaddr(3). Pointed-out-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- net/sunrpc/rpcb_clnt.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c index 03ae007641e..2caa7edeeab 100644 --- a/net/sunrpc/rpcb_clnt.c +++ b/net/sunrpc/rpcb_clnt.c @@ -703,11 +703,16 @@ static int rpcb_decode_getaddr(struct rpc_rqst *req, __be32 *p, *portp = 0; addr_len = ntohl(*p++); + if (addr_len == 0) { + dprintk("RPC: rpcb_decode_getaddr: " + "service is not registered\n"); + return 0; + } + /* - * Simple sanity check. The smallest possible universal - * address is an IPv4 address string containing 11 bytes. + * Simple sanity check. */ - if (addr_len < 11 || addr_len > RPCBIND_MAXUADDRLEN) + if (addr_len > RPCBIND_MAXUADDRLEN) goto out_err; /* -- 2.39.2