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='2020-03-10 20:26:52 +0100'>2020-03-10</span></td><td><a href='/guix/commit/doc/fdl-1.3.texi?id=21656ffa3b6d78a610f0befced20cc9b4b3baab6'>doc: Use HTTPS for external links.</a><span class='msg-avail'>...<span class='msg-tooltip'>* doc/contributing.texi
  (14.1 Building from Git,
   14.3 The Perfect Setup,
   14.4.1 Software Freedom,
   14.4.4 Synopses and Descriptions,
   14.5.4 Formatting Code):
   Use HTTPS for @uref{}s and @url{}s that support it.

* doc/fdl-1.3.texi
  (Appendix A GNU Free Documentation License):
  Use HTTPS for @uref{}s and @url{}s that support it.

* doc/guix.texi
  (6.3 Build Systems,
   8.8.4 Networking Services,
   8.8.8 Sound Services,
   8.8.16 Web Services,
   8.11 Name Service Switch,
   12.2 Preparing to Use the Bootstrap Binaries);
   Use HTTPS for @uref{}s and @url{}s that support it.

Signed-off-by: Marius Bakke &lt;mbakke@fastmail.com&gt;
</span></span></td><td>Vitaliy Shatrov</td></tr>