PR 6494 Internal error due to malformed relro header

[Alan Modra]

glibc ld.so only uses p_memsz of PT_GNU_RELRO so let's no fuss too much
if we find p_filesz doesn't match p_memsz, as in the libpthread.so
testcase given in the PR.  It's a bit of a mystery how we could have
generated such a relro header in the first place.

	PR 6494
	* elf.c (copy_elf_program_header): Do not check that PT_GNU_RELRO
	p_filesz and p_memsz are equal.  Use p_memsz as the segment size.
	(assign_file_positions_for_non_load_sections): Zap PT_GNU_RELRO
	if we don't find matching PT_LOAD when copying.

Index: bfd/elf.c
===================================================================
RCS file: /cvs/src/src/bfd/elf.c,v
retrieving revision 1.479
diff -u -p -r1.479 elf.c
--- bfd/elf.c	18 Mar 2009 16:26:54 -0000	1.479
+++ bfd/elf.c	26 Mar 2009 07:46:48 -0000
@@ -4683,13 +4680,11 @@ assign_file_positions_for_non_load_secti
 	      p->p_align = 1;
 	      p->p_flags = (lp->p_flags & ~PF_W);
 	    }
-	  else if (link_info != NULL)
+	  else
 	    {
 	      memset (p, 0, sizeof *p);
 	      p->p_type = PT_NULL;
 	    }
-	  else
-	    abort ();
 	}
       else if (m->count != 0)
 	{
@@ -5838,14 +5833,13 @@ copy_elf_program_header (bfd *ibfd, bfd 
       map->p_align_valid = 1;
       map->p_vaddr_offset = 0;
 
-      if (map->p_type == PT_GNU_RELRO
-	  && segment->p_filesz == segment->p_memsz)
+      if (map->p_type == PT_GNU_RELRO)
 	{
 	  /* The PT_GNU_RELRO segment may contain the first a few
 	     bytes in the .got.plt section even if the whole .got.plt
 	     section isn't in the PT_GNU_RELRO segment.  We won't
 	     change the size of the PT_GNU_RELRO segment.  */
-	  map->p_size = segment->p_filesz;
+	  map->p_size = segment->p_memsz;
 	  map->p_size_valid = 1;
 	}
 

-- 
Alan Modra
Australia Development Lab, IBM