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='2023-05-11 16:38:29 +0200'>2023-05-11</span></td><td><a href='/guix/commit/gnu/services/monitoring.scm?id=0e3bb48d363e2527401f168174f4586383bc6283'>services: Add vnstat-service-type.</a><span class='msg-avail'>...</span></td><td>Bruno Victal</td></tr>
<tr><td><span title='2023-02-27 23:40:43 +0100'>2023-02-27</span></td><td><a href='/guix/commit/gnu/services/monitoring.scm?id=43c36c5c9f7a31649eb059fd16ed82bde20da3fc'>ui: 'display-hint' quotes extra arguments for Texinfo.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>