[src/trunk]: src/sys/kern Remember the end of the last text segment and set u...

[joerg <joerg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/753cf8d7d5ff
branches:  trunk
changeset: 757619:753cf8d7d5ff
user:      joerg <joerg%NetBSD.org@localhost>
date:      Tue Sep 07 21:32:03 2010 +0000

description:
Remember the end of the last text segment and set up a fake data segment
if size 0 and starting after the text segments, if no data segment was
found. Unbreaks sbrk on platforms where all loaded segments are
executable (PR 43817). The cast of executable segments after data
segments is left out for now.

diffstat:

 sys/kern/exec_elf.c |  14 ++++++--------
 1 files changed, 6 insertions(+), 8 deletions(-)

diffs (56 lines):

diff -r a600fc153f6e -r 753cf8d7d5ff sys/kern/exec_elf.c
--- a/sys/kern/exec_elf.c       Tue Sep 07 21:11:10 2010 +0000
+++ b/sys/kern/exec_elf.c       Tue Sep 07 21:32:03 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: exec_elf.c,v 1.24 2010/08/20 14:59:53 joerg Exp $      */
+/*     $NetBSD: exec_elf.c,v 1.25 2010/09/07 21:32:03 joerg Exp $      */
 
 /*-
  * Copyright (c) 1994, 2000, 2005 The NetBSD Foundation, Inc.
@@ -57,7 +57,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(1, "$NetBSD: exec_elf.c,v 1.24 2010/08/20 14:59:53 joerg Exp $");
+__KERNEL_RCSID(1, "$NetBSD: exec_elf.c,v 1.25 2010/09/07 21:32:03 joerg Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_pax.h"
@@ -636,7 +636,7 @@
 {
        Elf_Ehdr *eh = epp->ep_hdr;
        Elf_Phdr *ph, *pp;
-       Elf_Addr phdr = 0, pos = 0;
+       Elf_Addr phdr = 0, pos = 0, end_text = 0;
        int error, i, nload;
        char *interp = NULL;
        u_long phsize;
@@ -737,9 +737,6 @@
                         * Consider this as text segment, if it is executable.
                         * If there is more than one text segment, pick the
                         * largest.
-                        *
-                        * If it is not executable, use the last section
-                        * as data segment to make break() happy.
                         */
                        if (ph[i].p_flags & PF_X) {
                                if (epp->ep_taddr == ELFDEFNNAME(NO_ADDR) ||
@@ -747,6 +744,7 @@
                                        epp->ep_taddr = addr;
                                        epp->ep_tsize = size;
                                }
+                               end_text = addr + size;
                        } else {
                                epp->ep_daddr = addr;
                                epp->ep_dsize = size;
@@ -775,8 +773,8 @@
        }
 
        if (epp->ep_daddr == ELFDEFNNAME(NO_ADDR)) {
-               epp->ep_daddr = epp->ep_taddr;
-               epp->ep_dsize = epp->ep_tsize;
+               epp->ep_daddr = end_text;
+               epp->ep_dsize = 0;
        }
 
        /*