File emacs-24-0019-ELF-unexec-align-section-header.p... of Package emacs

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File emacs-24-0019-ELF-unexec-align-section-header.patch of Package emacs (Revision 6345346ae4b931ed9579cd039ca05b77)

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From 0de7316751e94c29aeb4b75731ac6e8c9eba77e6 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Mon, 16 Nov 2015 17:48:08 -0800
Subject: ELF unexec: align section header
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Emacs should build on ppc64el.  A problem with the bss has been fixed.

This upstream patch has been added [10/10]:

ELF unexec: align section header

This ports the recent unexelf.c changes to Fedora x86-64
  when configured with GCC’s -fsanitize=undefined option.
  * src/unexelf.c (unexec): Align new_data2_size to a multiple
  of ElfW (Shdr)’s alignment, so that NEW_SECTION_H returns a
  pointer aligned appropriately for its type.

Origin: upstream, commit: c9fd597a4cffcae873b25381ee8cc755f0debe95
Bug: http://debbugs.gnu.org/20614
Bug-Debian: http://bugs.debian.org/808347
Added-by: Rob Browning <rlb@defaultvalue.org>
---
 src/unexelf.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/src/unexelf.c b/src/unexelf.c
index f2462d1..c69be0d 100644
--- a/src/unexelf.c
+++ b/src/unexelf.c
@@ -247,7 +247,7 @@ unexec (const char *new_name, const char *old_name)
 
   ElfW (Phdr) *old_bss_seg, *new_bss_seg;
   ElfW (Addr) old_bss_addr, new_bss_addr;
-  ElfW (Word) old_bss_size, new_data2_size;
+  ElfW (Word) old_bss_size, bss_size_growth, new_data2_size;
   ElfW (Off) old_bss_offset, new_data2_offset;
 
   ptrdiff_t n;
@@ -332,7 +332,11 @@ unexec (const char *new_name, const char *old_name)
 
   new_break = sbrk (0);
   new_bss_addr = (ElfW (Addr)) new_break;
-  new_data2_size = new_bss_addr - old_bss_addr;
+  bss_size_growth = new_bss_addr - old_bss_addr;
+  new_data2_size = bss_size_growth;
+  new_data2_size += alignof (ElfW (Shdr)) - 1;
+  new_data2_size -= new_data2_size % alignof (ElfW (Shdr));
+
   new_data2_offset = old_bss_offset;
 
 #ifdef UNEXELF_DEBUG
@@ -400,7 +404,8 @@ unexec (const char *new_name, const char *old_name)
   new_bss_seg->p_memsz = new_bss_seg->p_filesz;
 
   /* Copy over what we have in memory now for the bss area. */
-  memcpy (new_base + new_data2_offset, (caddr_t) old_bss_addr, new_data2_size);
+  memcpy (new_base + new_data2_offset, (caddr_t) old_bss_addr,
+	  bss_size_growth);
 
   /* Walk through all section headers, copying data and updating.  */
   for (n = 1; n < old_file_h->e_shnum; n++)

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File emacs-24-0019-ELF-unexec-align-section-header.patch of Package emacs (Revision 6345346ae4b931ed9579cd039ca05b77)

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