From 3ae13c8b20856f1003f3e26ee1e578bfeff024e3 Mon Sep 17 00:00:00 2001
From: kib <kib@FreeBSD.org>
Date: Sun, 27 Apr 2014 05:28:14 +0000
Subject: Fix order of libthr and libc in the global dso list for sshd, by
 explicitely linking main binary with -lpthread.  Before, libthr appeared in
 the list due to dependency of one of the kerberos libs. Due to the change in
 ld(1) behaviour of not copying NEEDED entries from direct dependencies into
 the link results, the order becomes reversed.

The libthr must appear before libc to properly interpose libc symbols
and provide working rtld locks implementation.  The symptom was sshd
hanging on rtld bind lock during nested symbol binding from a signal
handler.

Approved by:	des (openssh maintainer)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
---
 secure/usr.sbin/sshd/Makefile | 10 ++++++++++
 1 file changed, 10 insertions(+)

(limited to 'secure')

diff --git a/secure/usr.sbin/sshd/Makefile b/secure/usr.sbin/sshd/Makefile
index 4f730a9..e1c71a3 100644
--- a/secure/usr.sbin/sshd/Makefile
+++ b/secure/usr.sbin/sshd/Makefile
@@ -57,6 +57,16 @@ CFLAGS+= -DNONE_CIPHER_ENABLED
 DPADD+= ${LIBCRYPT} ${LIBCRYPTO} ${LIBZ}
 LDADD+= -lcrypt -lcrypto -lz
 
+# Fix the order of NEEDED entries for libthr and libc. The libthr
+# needs to interpose libc symbols, leaving the libthr loading as
+# dependency of krb causes reversed order and broken interposing. Put
+# the threading library last on the linker command line, just before
+# the -lc added by a compiler driver.
+.if ${MK_KERBEROS_SUPPORT} != "no"
+DPADD+= ${LIBPTHREAD}
+LDADD+= -lpthread
+.endif
+
 .if defined(LOCALBASE)
 CFLAGS+= -DXAUTH_PATH=\"${LOCALBASE}/bin/xauth\"
 .endif
-- 
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