Fix CVE-2017-8779:

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-8779

Patch copied from the bug reporter's 3rd-party repository:

https://github.com/guidovranken/rpcbomb/blob/master/rpcbind_patch.txt

diff --git a/src/rpcb_svc_com.c b/src/rpcb_svc_com.c
index 5862c26..e11f61b 100644
--- a/src/rpcb_svc_com.c
+++ b/src/rpcb_svc_com.c
@@ -48,6 +48,7 @@
 #include <rpc/rpc.h>
 #include <rpc/rpcb_prot.h>
 #include <rpc/svc_dg.h>
+#include <rpc/rpc_com.h>
 #include <netconfig.h>
 #include <errno.h>
 #include <syslog.h>
@@ -432,7 +433,7 @@ rpcbproc_taddr2uaddr_com(void *arg, struct svc_req *rqstp /*__unused*/,
 static bool_t
 xdr_encap_parms(XDR *xdrs, struct encap_parms *epp)
 {
-	return (xdr_bytes(xdrs, &(epp->args), (u_int *) &(epp->arglen), ~0));
+	return (xdr_bytes(xdrs, &(epp->args), (u_int *) &(epp->arglen), RPC_MAXDATASIZE));
 }
 
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<tr><td><span title='2018-12-23 16:37:51 +0200'>2018-12-23</span></td><td><a href='/guix/commit/gnu/packages/datamash.scm?id=b83ddd03d961ea0a0cf75eb6649ecec4fbd4fb94'>gnu: datamash: Update to 1.4.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-04-12 22:55:51 -0500'>2018-04-12</span></td><td><a href='/guix/commit/gnu/packages/datamash.scm?id=de7f234a3a3e583e7af832e956b44455c71dc5cb'>gnu: datamash: Fix tests on ARM systems.</a><span class='msg-avail'>...</span></td><td>Eric Bavier</td></tr>
<tr><td><span title='2018-03-18 00:02:06 +0100'>2018-03-18</span></td><td><a href='/guix/commit/gnu/packages/datamash.scm?id=80f565d3137eceb479b8f7d39c26e00385dd65f6'>gnu: datamash: Update to 1.3.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-08-24 10:35:00 +0300'>2017-08-24</span></td><td><a href='/guix/commit/gnu/packages/datamash.scm?id=c47048c328843bcc26772bd6c96d03962972b173'>gnu: datamash: Update to 1.2.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>