[PATCH] elf: Properly compute offsets of desc and next note

[Nick Clifton]

Hi H.J.

+  /* NB: CORE PT_NOTE segments may have p_align values of 0 or 1.
+     gABI specifies that PT_NOTE alignment should be aligned to 4
+     bytes for 32-bit objects and to 8 bytes for 64-bit objects.  If
+     align is less than 4, we use 4 byte alignment.   */
+  if (align < 4)
+    align = 4;

It occurs to me that we probably ought to be paranoid here and check for
other problematic alignments.  Ie:

  if (align < 4)
    align = 4;
  else if (align > 4)
    align = 8;

Otherwise I bet someone will come up with a fuzzed binary that does something nasty.

Hmm, actually you will probably point out that the checks later on will prevent an
illegal memory access, so how about this instead:

  if (align < 4)
    align = 4;
  else if (align != 4 && align != 8)
    return FALSE;

(We probably ought to check the return value from elf_parse_notes() in 
_bfd_elf_make_section_from_shdr as well).

What do you think ?

Cheers
  Nick