From 0b1e027b12ae755d22b030b29066222b24b6a4cb Mon Sep 17 00:00:00 2001
From: "Todd C. Miller" <Todd.Miller@courtesan.com>
Date: Fri, 15 May 2015 15:48:24 -0600
Subject: [PATCH] Force flat namespace on darwin to make the getenv() hooking
 work as it does on ELF.

---
 configure       | 41 +++++++++++++++++++++++++++++++++++++++++
 configure.ac    |  5 +++++
 src/Makefile.in |  3 ++-
 3 files changed, 48 insertions(+), 1 deletion(-)

diff --git a/configure b/configure
index 6fb5e4991..2d98bac5d 100755
--- a/configure
+++ b/configure
@@ -792,6 +792,7 @@ LT_LDFLAGS
 ZLIB_LDFLAGS
 LIBUTIL_LDFLAGS
 SUDOERS_LDFLAGS
+SUDO_LDFLAGS
 LDFLAGS
 CPPFLAGS
 PROGS
@@ -2843,6 +2844,7 @@ $as_echo "$as_me: Configuring Sudo version $PACKAGE_VERSION" >&6;}
 
 
 
+
 
 
 #
@@ -15213,6 +15215,45 @@ done
 		fi
 		RTLD_PRELOAD_VAR="DYLD_INSERT_LIBRARIES"
 
+		# We need to force a flat namespace to make libc
+		# symbol hooking work like it does on ELF.
+		{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the linker accepts -Wl,-force_flat_namespace" >&5
+$as_echo_n "checking whether the linker accepts -Wl,-force_flat_namespace... " >&6; }
+if ${ax_cv_check_ldflags___Wl__force_flat_namespace+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$LDFLAGS
+  LDFLAGS="$LDFLAGS  -Wl,-force_flat_namespace"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ax_cv_check_ldflags___Wl__force_flat_namespace=yes
+else
+  ax_cv_check_ldflags___Wl__force_flat_namespace=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+  LDFLAGS=$ax_check_save_flags
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_check_ldflags___Wl__force_flat_namespace" >&5
+$as_echo "$ax_cv_check_ldflags___Wl__force_flat_namespace" >&6; }
+if test x"$ax_cv_check_ldflags___Wl__force_flat_namespace" = xyes; then :
+  SUDO_LDFLAGS="${SUDO_LDFLAGS}${SUDO_LDFLAGS+ }-Wl,-force_flat_namespace"
+else
+  :
+fi
+
+
 		# Examples go in share/examples/sudo
 		if test X"$with_exampledir" = X""; then
 		    exampledir='$(datarootdir)/examples/$(PACKAGE_TARNAME)'
diff --git a/configure.ac b/configure.ac
index d2be85ef9..7ee0ee444 100644
--- a/configure.ac
+++ b/configure.ac
@@ -20,6 +20,7 @@ AC_SUBST([CFLAGS])
 AC_SUBST([PROGS])
 AC_SUBST([CPPFLAGS])
 AC_SUBST([LDFLAGS])
+AC_SUBST([SUDO_LDFLAGS])
 AC_SUBST([SUDOERS_LDFLAGS])
 AC_SUBST([LIBUTIL_LDFLAGS])
 AC_SUBST([ZLIB_LDFLAGS])
@@ -2110,6 +2111,10 @@ case "$host" in
 		fi
 		RTLD_PRELOAD_VAR="DYLD_INSERT_LIBRARIES"
 
+		# We need to force a flat namespace to make libc
+		# symbol hooking work like it does on ELF.
+		AX_CHECK_LINK_FLAG([-Wl,-force_flat_namespace], [SUDO_LDFLAGS="${SUDO_LDFLAGS}${SUDO_LDFLAGS+ }-Wl,-force_flat_namespace"])
+
 		# Examples go in share/examples/sudo
 		if test X"$with_exampledir" = X""; then
 		    exampledir='$(datarootdir)/examples/$(PACKAGE_TARNAME)'
diff --git a/src/Makefile.in b/src/Makefile.in
index ea4f562b9..e5eca3f70 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -48,6 +48,7 @@ CFLAGS = @CFLAGS@
 
 # Flags to pass to the link stage
 LDFLAGS = @LDFLAGS@
+SUDO_LDFLAGS = $(LDFLAGS) @SUDO_LDFLAGS@
 LT_LDFLAGS = @LT_LDFLAGS@
 
 # PIE flags
@@ -130,7 +131,7 @@ Makefile: $(srcdir)/Makefile.in
 	$(LIBTOOL) --mode=compile $(CC) -c $(CPPFLAGS) $(CFLAGS) $(PIE_CFLAGS) $(SSP_CFLAGS) $(DEFS) $<
 
 sudo: $(OBJS) $(LT_LIBS) @STATIC_SUDOERS@
-	$(LIBTOOL) --mode=link $(CC) -o $@ $(OBJS) $(LDFLAGS) $(PIE_LDFLAGS) $(SSP_LDFLAGS) $(LIBS) @STATIC_SUDOERS@
+	$(LIBTOOL) --mode=link $(CC) -o $@ $(OBJS) $(SUDO_LDFLAGS) $(PIE_LDFLAGS) $(SSP_LDFLAGS) $(LIBS) @STATIC_SUDOERS@
 
 sudo_noexec.la: sudo_noexec.lo
 	$(LIBTOOL) --mode=link $(CC) $(LDFLAGS) $(LT_LDFLAGS) $(SSP_LDFLAGS) -o $@ sudo_noexec.lo -module -avoid-version -rpath $(noexecdir) -shrext .so
-- 
2.40.0