Blob Blame History Raw
This patch is based on the following upstream commit:

commit 94a4e9e4f401ffe829a992820439977ead0a0ce7
Author: Florian Weimer <fweimer@redhat.com>
Date:   Thu Apr 25 10:41:43 2019 +0200

    Extend BIND_NOW to installed programs with --enable-bind-now
    
    Commit 2d6ab5df3b675e96ee587ae6a8c2ce004c6b1ba9 ("Document and fix
    --enable-bind-now [BZ #21015]") extended BIND_NOW to all installed
    shared objects.  This change also covers installed programs.
    
    Reviewed-by: Carlos O'Donell <carlos@redhat.com>

diff --git a/INSTALL b/INSTALL
index 230be71b9d0821c2..277ea46d9c25a9ae 100644
--- a/INSTALL
+++ b/INSTALL
@@ -144,10 +144,10 @@ will be used, and CFLAGS sets optimization options for the compiler.
      Enable lock elision for pthread mutexes by default.
 
 '--enable-bind-now'
-     Disable lazy binding for installed shared objects.  This provides
-     additional security hardening because it enables full RELRO and a
-     read-only global offset table (GOT), at the cost of slightly
-     increased program load times.
+     Disable lazy binding for installed shared objects and programs.
+     This provides additional security hardening because it enables full
+     RELRO and a read-only global offset table (GOT), at the cost of
+     slightly increased program load times.
 
 `--disable-werror'
      By default, the GNU C Library is built with `-Werror'.  If you wish
diff --git a/Makeconfig b/Makeconfig
index 1ad9b6f0d494c027..bc13b39c2ea5708a 100644
--- a/Makeconfig
+++ b/Makeconfig
@@ -389,6 +389,8 @@ endif
 # test modules.
 ifeq ($(bind-now),yes)
 LDFLAGS-lib.so += -Wl,-z,now
+# Extra flags for dynamically linked non-test main programs.
+link-extra-flags += -Wl,-z,now
 endif
 
 # Additional libraries to link into every test.
@@ -405,7 +407,8 @@ ifndef +link-pie
 						    S$(start-installed-name))\
 			  $(+preinit) $(link-extra-libs) \
 			  $(common-objpfx)libc% $(+postinit),$^) \
-	     $(link-extra-libs) $(link-libc) $(+postctorS) $(+postinit)
+	     $(link-extra-libs) $(link-extra-flags) $(link-libc) \
+	     $(+postctorS) $(+postinit)
 endif
 # Command for statically linking programs with the C library.
 ifndef +link-static
@@ -419,8 +422,8 @@ ifndef +link-static
 			   $(common-objpfx)libc% $(+postinit),$^) \
 	      $(link-extra-libs-static)
 +link-static-after-libc = $(+postctorT) $(+postinit)
-+link-static = $(+link-static-before-libc) $(link-libc-static) \
-	       $(+link-static-after-libc)
++link-static = $(+link-static-before-libc) $(link-extra-flags) \
+	       $(link-libc-static) $(+link-static-after-libc)
 +link-static-tests = $(+link-static-before-libc) $(link-libc-static-tests) \
 		     $(+link-static-after-libc)
 endif
@@ -438,7 +441,8 @@ ifeq (yes,$(build-shared))
 			   $(common-objpfx)libc% $(+postinit),$^) \
 	      $(link-extra-libs)
 +link-after-libc = $(+postctor) $(+postinit)
-+link = $(+link-before-libc) $(link-libc) $(+link-after-libc)
++link = $(+link-before-libc) $(link-extra-flags) $(link-libc) \
+	$(+link-after-libc)
 +link-tests = $(+link-before-libc) $(link-libc-tests) $(+link-after-libc)
 else
 +link = $(+link-static)
diff --git a/manual/install.texi b/manual/install.texi
index 47d832cc59bc695e..5cacd974ce093ce9 100644
--- a/manual/install.texi
+++ b/manual/install.texi
@@ -161,10 +161,10 @@ so that they can be invoked directly.
 Enable lock elision for pthread mutexes by default.
 
 @item --enable-bind-now
-Disable lazy binding for installed shared objects.  This provides
-additional security hardening because it enables full RELRO and a
-read-only global offset table (GOT), at the cost of slightly increased
-program load times.
+Disable lazy binding for installed shared objects and programs.  This
+provides additional security hardening because it enables full RELRO
+and a read-only global offset table (GOT), at the cost of slightly
+increased program load times.
 
 @pindex pt_chown
 @findex grantpt