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));
 }
 
 /*
value='switch'/></form></td></tr>
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<tr><td><span title='2024-04-15 22:36:42 +0200'>2024-04-15</span></td><td><a href='/guix/commit/tests/cpio.scm?id=54be7795b5cc2f6cad05f8649121372c9d5af806'>utils: Don’t re-export ‘call-with-temporary-output-file’.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/utils.scm: Remove re-export of ‘call-with-temporary-output-file’.
Autoload a number of modules.
* guix/download.scm, guix/import/hackage.scm,
guix/import/hexpm.scm, guix/import/opam.scm,
guix/import/pypi.scm, tests/cpio.scm, tests/egg.scm,
tests/opam.scm, tests/publish.scm, tests/store-database.scm,
tests/utils.scm: Adjust imports accordingly.

Change-Id: I3f5e94631397996a30be2ea4ff8b50a3371e8ee7
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-12-20 16:56:03 +0100'>2022-12-20</span></td><td><a href='/guix/commit/tests/cpio.scm?id=2880dc3046170e9129437caca586f13956d0d811'>cpio: Skip test on inode numbers that don't fit on 32 bits.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://issues.guix.gnu.org/60202&gt;.
Reported by Christopher Baines &lt;mail@cbaines.net&gt;.

* tests/cpio.scm (%test-file): New variable.
("file-&gt;cpio-header + write-cpio-header + read-cpio-header"): Use it.
Skip test when the inode number of %TEST-FILE is too big.
</span></span></td><td>Ludovic Courtès</td></tr>