[binutils-gdb] Tidy commit 49910fd88dcd

[Alan Modra]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=f8dd36465839e5bc60ffc5e894633d430ec55a06

commit f8dd36465839e5bc60ffc5e894633d430ec55a06
Author: Alan Modra <amodra@gmail.com>
Date:   Sat Jul 10 10:07:17 2021 +0930

    Tidy commit 49910fd88dcd
    
    Pointer range checking is UB if the values compared are outside the
    underlying array elements (plus one).
    
            * dwarf2.c (read_address): Remove accidental commit.
            (read_ranges): Compare offset rather than pointers.

Diff:
---
 bfd/ChangeLog | 5 +++++
 bfd/dwarf2.c  | 9 +++------
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 9cbb9f91dd4..4dc3d685255 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,8 @@
+2021-07-10  Alan Modra  <amodra@gmail.com>
+
+	* dwarf2.c (read_address): Remove accidental commit.
+	(read_ranges): Compare offset rather than pointers.
+
 2021-07-08  Nick Clifton  <nickc@redhat.com>
 
 	* po/pt.po: Updated Portuguese translation.
diff --git a/bfd/dwarf2.c b/bfd/dwarf2.c
index 1247f952def..04f56a7b187 100644
--- a/bfd/dwarf2.c
+++ b/bfd/dwarf2.c
@@ -909,8 +909,7 @@ read_address (struct comp_unit *unit, bfd_byte **ptr, bfd_byte *buf_end)
   if (bfd_get_flavour (unit->abfd) == bfd_target_elf_flavour)
     signed_vma = get_elf_backend_data (unit->abfd)->sign_extend_vma;
 
-  if (unit->addr_size > (size_t) (buf_end - buf)
-      || (buf > buf_end))
+  if (unit->addr_size > (size_t) (buf_end - buf))
     {
       *ptr = buf_end;
       return 0;
@@ -3094,12 +3093,10 @@ read_ranges (struct comp_unit *unit, struct arange *arange,
 	return false;
     }
 
-  ranges_ptr = unit->file->dwarf_ranges_buffer + offset;
-  if (ranges_ptr < unit->file->dwarf_ranges_buffer)
+  if (offset > unit->file->dwarf_ranges_size)
     return false;
+  ranges_ptr = unit->file->dwarf_ranges_buffer + offset;
   ranges_end = unit->file->dwarf_ranges_buffer + unit->file->dwarf_ranges_size;
-  if (ranges_ptr >= ranges_end)
-    return false;
 
   for (;;)
     {