svn commit: r265003 - head/secure/usr.sbin/sshd

[Konstantin Belousov]

Author: kib
Date: Sun Apr 27 05:28:14 2014
New Revision: 265003
URL: http://svnweb.freebsd.org/changeset/base/265003

Log:
  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

Modified:
  head/secure/usr.sbin/sshd/Makefile

Modified: head/secure/usr.sbin/sshd/Makefile
==============================================================================
--- head/secure/usr.sbin/sshd/Makefile	Sun Apr 27 05:19:01 2014	(r265002)
+++ head/secure/usr.sbin/sshd/Makefile	Sun Apr 27 05:28:14 2014	(r265003)
@@ -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