libc NLS, NFS mounted /usr/local, DHCP, no default route causes hangs

[Jilles Tjoelker]

On Fri, Apr 23, 2010 at 04:17:36PM +0200, Jilles Tjoelker wrote:
> The changes to use NLS for strerror sometimes cause one of my virtual
> machines to deadlock. This virtual machine runs 9-CURRENT, acquires its
> IP address via DHCP (virtualbox host-only networking), has no default
> route and has /usr/local and /usr/home NFS mounted.

> When the DHCP lease expires such as by resetting the date after a VM
> save&restore, one of the route(8) commands executed by
> dhclient-script(8) fails and calls strerror(3). Following the default
> NLSPATH, catopen(3) looks in /usr/share/nls first; because the catalog
> is not there it then tries in /usr/local/share/nls which deadlocks
> because the network is not available.

> I currently use the attached patch which returns failure on any attempt
> to open a catalog for language "C", but I think this is not correct.
> Am I using a configuration that is not supposed to work (NFS mounted
> /usr/local with DHCP in particular), or should this be fixed in some
> other way?

The patch:

Index: lib/libc/nls/msgcat.c
===================================================================
--- lib/libc/nls/msgcat.c	(revision 206760)
+++ lib/libc/nls/msgcat.c	(working copy)
@@ -138,6 +138,9 @@
 			lang = "C";
 	}
 
+	if (strcmp(lang, "C") == 0)
+		NLRETERR(ENOENT);
+
 	/* Try to get it from the cache first */
 	RLOCK(NLERR);
 	SLIST_FOREACH(np, &cache, list) {

-- 
Jilles Tjoelker