From 734fb3ac6c3e5708ed05b6c5b1d8af92838ee3f5 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@penguin.cs.ucla.edu>
Date: Wed, 27 Apr 2016 15:52:53 -0700
Subject: [PATCH] Port dumping to NetBSD with PaX

Problem reported by Thomas Klausner (Bug#23371).
* configure.ac (PAXCTL_dumped, PAXCTL_notdumped): New vars.
Set them to setfattr and/or paxctl commands appropriate for
GNU/Linux and/or NetBSD; the latter prefers paxctl +a.  Search
for paxctl only if setfattr is not found.
* src/Makefile.in (PAXCTL_dumped, PAXCTL_notdumped):
New vars, replacing PAXCTL_if_present and SETFATTR_if_present.
All uses changed.
---
 configure.ac    | 38 +++++++++++++++++++++++++++++---------
 src/Makefile.in | 18 ++++++++++++------
 2 files changed, 41 insertions(+), 15 deletions(-)

diff --git a/configure.ac b/configure.ac
index 4f169b67dc3..8f8c38bd832 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1140,16 +1140,9 @@ AC_PATH_PROG(GZIP_PROG, gzip)
 test $with_compress_install != yes && test -n "$GZIP_PROG" && \
    GZIP_PROG=" # $GZIP_PROG # (disabled by configure --without-compress-install)"
 
+PAXCTL_dumped=
+PAXCTL_notdumped=
 if test $opsys = gnu-linux; then
-  AC_PATH_PROG(PAXCTL, paxctl,,
-    [$PATH$PATH_SEPARATOR/sbin$PATH_SEPARATOR/usr/sbin])
-  if test "X$PAXCTL" != X; then
-    AC_MSG_CHECKING([whether binaries have a PT_PAX_FLAGS header])
-    AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
-      [if $PAXCTL -v conftest$EXEEXT >/dev/null 2>&1; then AC_MSG_RESULT(yes)
-      else AC_MSG_RESULT(no); PAXCTL=""; fi])
-  fi
-
   if test "${SETFATTR+set}" != set; then
     AC_CACHE_CHECK([for setfattr],
       [emacs_cv_prog_setfattr],
@@ -1160,6 +1153,7 @@ if test $opsys = gnu-linux; then
 	 emacs_cv_prog_setfattr=no
        fi])
     if test "$emacs_cv_prog_setfattr" = yes; then
+      PAXCTL_notdumped='$(SETFATTR) -n user.pax.flags -v er'
       SETFATTR=setfattr
     else
       SETFATTR=
@@ -1168,6 +1162,32 @@ if test $opsys = gnu-linux; then
     AC_SUBST([SETFATTR])
   fi
 fi
+case $opsys,$PAXCTL_notdumped in
+  gnu-linux, | netbsd,)
+    AC_PATH_PROG([PAXCTL], [paxctl], [],
+      [$PATH$PATH_SEPARATOR/sbin$PATH_SEPARATOR/usr/sbin])
+    if test -n "$PAXCTL"; then
+      if test "$opsys" = netbsd; then
+	PAXCTL_dumped='$(PAXCTL) +a'
+	PAXCTL_notdumped=$PAXCTL_dumped
+      else
+	AC_MSG_CHECKING([whether binaries have a PT_PAX_FLAGS header])
+	AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
+	  [if $PAXCTL -v conftest$EXEEXT >/dev/null 2>&1; then
+	     AC_MSG_RESULT([yes])
+	   else
+	     AC_MSG_RESULT([no])
+	     PAXCTL=
+	   fi])
+	if test -n "$PAXCTL"; then
+	  PAXCTL_dumped='$(PAXCTL) -zex'
+	  PAXCTL_notdumped='$(PAXCTL) -r'
+	fi
+      fi
+    fi;;
+esac
+AC_SUBST([PAXCTL_dumped])
+AC_SUBST([PAXCTL_notdumped])
 
 ## Need makeinfo >= 4.7 (?) to build the manuals.
 if test "$MAKEINFO" != "no"; then
diff --git a/src/Makefile.in b/src/Makefile.in
index 1f0df6f3ec8..d54670932d3 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -114,8 +114,9 @@ TEMACS_LDFLAGS = $(LD_SWITCH_SYSTEM) $(LD_SWITCH_SYSTEM_TEMACS)
 ## around this, newer ones setfattr.  See Bug#11398 and Bug#16343.
 PAXCTL = @PAXCTL@
 SETFATTR = @SETFATTR@
-PAXCTL_if_present = $(or $(PAXCTL),: paxctl)
-SETFATTR_if_present = $(or $(SETFATTR),: setfattr)
+## Commands to set PaX flags on dumped and not-dumped instances of Emacs.
+PAXCTL_dumped = @PAXCTL_dumped@
+PAXCTL_notdumped = @PAXCTL_notdumped@
 
 ## Some systems define this to request special libraries.
 LIBS_SYSTEM=@LIBS_SYSTEM@
@@ -532,7 +533,9 @@ ifeq ($(CANNOT_DUMP),yes)
 	ln -f temacs$(EXEEXT) $@
 else
 	LC_ALL=C $(RUN_TEMACS) -batch -l loadup dump
-	$(PAXCTL_if_present) -zex $@
+  ifneq ($(PAXCTL_dumped),)
+	$(PAXCTL_dumped) $@
+  endif
 	ln -f $@ bootstrap-emacs$(EXEEXT)
 endif
 
@@ -594,8 +597,9 @@ temacs$(EXEEXT): $(LIBXMENU) $(ALLOBJS) \
 	  -o temacs $(ALLOBJS) $(lib)/libgnu.a $(W32_RES_LINK) $(LIBES)
 	$(MKDIR_P) $(etc)
 ifneq ($(CANNOT_DUMP),yes)
-	$(PAXCTL_if_present) -r $@
-	$(SETFATTR_if_present) -n user.pax.flags -v er $@
+  ifneq ($(PAXCTL_notdumped),)
+	$(PAXCTL_notdumped) $@
+  endif
 endif
 
 ## The following oldxmenu-related rules are only (possibly) used if
@@ -734,7 +738,9 @@ ifeq ($(CANNOT_DUMP),yes)
 	ln -f temacs$(EXEEXT) $@
 else
 	$(RUN_TEMACS) --batch --load loadup bootstrap
-	$(PAXCTL_if_present) -zex emacs$(EXEEXT)
+  ifneq ($(PAXCTL_dumped),)
+	$(PAXCTL_dumped) emacs$(EXEEXT)
+  endif
 	mv -f emacs$(EXEEXT) $@
 endif
 	@: Compile some files earlier to speed up further compilation.
-- 
2.39.2