[binutils-gdb/binutils-2_30-branch] Import patch from mainline to fix a bug that would place executable and non-executables pages in the

[Nick Clifton <nickc at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=355d8ed79b1e830d5216a70026f751f5a38df9e9

commit 355d8ed79b1e830d5216a70026f751f5a38df9e9
Author: Nick Clifton <nickc@redhat.com>
Date:   Thu Feb 15 16:21:02 2018 +0000

    Import patch from mainline to fix a bug that would place executable and non-executables pages in the same segment.
    
    	PR 22758
    bfd	* elf.c (_bfd_elf_map_sections_to_segments): Don't start a new
    	segment when demand paged with lma on the same page.  Test this
    	before load/non-load, executable/non-executable,
    	writable/non-writable tests and simplify.  Delete bogus relro
    	condition in writable/non-writable test.  Delete outdated
    	comment.  Formatting.

Diff:
---
 bfd/ChangeLog | 13 +++++++++++++
 bfd/elf.c     | 42 +++++++++++++++++-------------------------
 2 files changed, 30 insertions(+), 25 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index ecd27e5..2cac4d2 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,16 @@
+2018-02-15  Nick Clifton  <nickc@redhat.com>
+
+	Import patch from mainline:
+	2018-01-30  Alan Modra  <amodra@gmail.com>
+
+	PR 22758
+	* elf.c (_bfd_elf_map_sections_to_segments): Don't start a new
+	segment when demand paged with lma on the same page.  Test this
+	before load/non-load, executable/non-executable,
+	writable/non-writable tests and simplify.  Delete bogus relro
+	condition in writable/non-writable test.  Delete outdated
+	comment.  Formatting.
+
 2018-02-15  Eric Botcazou  <ebotcazou@adacore.com>
 
 	PR ld/22832
diff --git a/bfd/elf.c b/bfd/elf.c
index c132098..325bdd5 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -4727,33 +4727,35 @@ _bfd_elf_map_sections_to_segments (bfd *abfd, struct bfd_link_info *info)
 		 the previous section, then we need a new segment.  */
 	      new_segment = TRUE;
 	    }
+	  else if ((abfd->flags & D_PAGED) != 0
+		   && (((last_hdr->lma + last_size - 1) & -maxpagesize)
+		       == (hdr->lma & -maxpagesize)))
+	    {
+	      /* If we are demand paged then we can't map two disk
+		 pages onto the same memory page.  */
+	      new_segment = FALSE;
+	    }
 	  /* In the next test we have to be careful when last_hdr->lma is close
 	     to the end of the address space.  If the aligned address wraps
 	     around to the start of the address space, then there are no more
 	     pages left in memory and it is OK to assume that the current
 	     section can be included in the current segment.  */
-	  else if ((BFD_ALIGN (last_hdr->lma + last_size, maxpagesize) + maxpagesize
-		    > last_hdr->lma)
-		   && (BFD_ALIGN (last_hdr->lma + last_size, maxpagesize) + maxpagesize
-		       <= hdr->lma))
+	  else if ((BFD_ALIGN (last_hdr->lma + last_size, maxpagesize)
+		    + maxpagesize > last_hdr->lma)
+		   && (BFD_ALIGN (last_hdr->lma + last_size, maxpagesize)
+		       + maxpagesize <= hdr->lma))
 	    {
 	      /* If putting this section in this segment would force us to
 		 skip a page in the segment, then we need a new segment.  */
 	      new_segment = TRUE;
 	    }
 	  else if ((last_hdr->flags & (SEC_LOAD | SEC_THREAD_LOCAL)) == 0
-		   && (hdr->flags & (SEC_LOAD | SEC_THREAD_LOCAL)) != 0
-		   && ((abfd->flags & D_PAGED) == 0
-		       || (((last_hdr->lma + last_size - 1) & -maxpagesize)
-			   != (hdr->lma & -maxpagesize))))
+		   && (hdr->flags & (SEC_LOAD | SEC_THREAD_LOCAL)) != 0)
 	    {
 	      /* We don't want to put a loaded section after a
 		 nonloaded (ie. bss style) section in the same segment
 		 as that will force the non-loaded section to be loaded.
-		 Consider .tbss sections as loaded for this purpose.
-		 However, like the writable/non-writable case below,
-		 if they are on the same page then they must be put
-		 in the same segment.  */
+		 Consider .tbss sections as loaded for this purpose.  */
 	      new_segment = TRUE;
 	    }
 	  else if ((abfd->flags & D_PAGED) == 0)
@@ -4769,21 +4771,11 @@ _bfd_elf_map_sections_to_segments (bfd *abfd, struct bfd_link_info *info)
 	    {
 	      new_segment = TRUE;
 	    }
-	  else if (! writable
-		   && (hdr->flags & SEC_READONLY) == 0
-		   && ((info != NULL
-			&& info->relro_end > info->relro_start)
-		       || (((last_hdr->lma + last_size - 1) & -maxpagesize)
-			   != (hdr->lma & -maxpagesize))))
+          else if (! writable
+		   && (hdr->flags & SEC_READONLY) == 0)
 	    {
 	      /* We don't want to put a writable section in a read only
-		 segment, unless they are on the same page in memory
-		 anyhow and there is no RELRO segment.  We already
-		 know that the last section does not bring us past the
-		 current section on the page, so the only case in which
-		 the new section is not on the same page as the previous
-		 section is when the previous section ends precisely on
-		 a page boundary.  */
+		 segment.  */
 	      new_segment = TRUE;
 	    }
 	  else