Taken from https://salsa.debian.org/debian/libtirpc/-/raw/master/debian/patches/06-hurd-client-port.diff

Description: Fix client code for hurd, avoiding malloc overflow
 When trying to setup a inet connection, it happens the following:
 - in libtirp, src/clnt_vc.c, clnt_vc_create gets called
 - when trying to allocate vc_fd_locks, __rpc_dtbsize() is used as size
   for that array of fd locks
 - __rpc_dtbsize(), in src/rpc_generic.c, queries using rlimit the
   maximum (rlim_max) number of file descriptors (RLIMIT_NOFILE):
   - on Linux, the default is { rlim_cur = 1024, rlim_max = 4096 }
   - on kFreeBSD, the default is { rlim_cur = 1024, rlim_max = 1024 }
   - on Hurd, the default is { rlim_cur = 1024, rlim_max = RLIM_INFINITY }
  meaning that on Hurd the memory allocation fails (as
  __rpc_dtbsize() * sizeof(int) overflows and is negative)

 Change libtiprc so __rpc_dtbsize falls back on rlim_cur if rlim_max
 is unlimited.

 This patch fixes the client connection using inet sockets; local unix
 sockets are not working, for two reasons so far:
 - getpeername on them gives EOPNOTSUPP
 - SO_REUSEADDR is not implemented for them
Author: Pino Toscano <pino@debian.org>

Bug-Debian: http://bugs.debian.org/739674
Forwarded: no
Reviewed-By: Petter Reinholdtsen
Last-Update: 2014-03-03

--- a/src/rpc_generic.c
+++ b/src/rpc_generic.c
@@ -107,12 +107,17 @@
 {
 	static int tbsize;
 	struct rlimit rl;
+	rlim_t lim;
 
 	if (tbsize) {
 		return (tbsize);
 	}
 	if (getrlimit(RLIMIT_NOFILE, &rl) == 0) {
-		return (tbsize = (int)rl.rlim_max);
+		lim = rl.rlim_max;
+		if (lim == RLIM_INFINITY) {
+			lim = rl.rlim_cur;
+		}
+		return (tbsize = (int)lim);
 	}
 	/*
 	 * Something wrong.  I'll try to save face by returning a
