[PATCH] Fix crash when disassembling invalid range on powerpc vle

[Luis Machado]

I got a report of a gdb crash for vle and further investigation showed an
attempt to disassemble an invalid memory range.  I tracked the crash down
to the code in get_powerpc_dialect, where we fail to make sure we have a
valid section pointer before dereferencing it.

There is no such problem for rs6000-based disassembling.

The following patch fixes this.

OK?

opcodes/ChangeLog:

2016-12-08  Luis Machado  <lgustavo@codesourcery.com>

	* ppc-dis.c (get_powerpc_dialect): Check NULL info->section.
---
 opcodes/ppc-dis.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/opcodes/ppc-dis.c b/opcodes/ppc-dis.c
index da1301e..efca157 100644
--- a/opcodes/ppc-dis.c
+++ b/opcodes/ppc-dis.c
@@ -236,7 +236,7 @@ get_powerpc_dialect (struct disassemble_info *info)
 
   /* Disassemble according to the section headers flags for VLE-mode.  */
   if (dialect & PPC_OPCODE_VLE
-      && info->section->owner != NULL
+      && info->section != NULL && info->section->owner != NULL
       && bfd_get_flavour (info->section->owner) == bfd_target_elf_flavour
       && elf_object_id (info->section->owner) == PPC32_ELF_DATA
       && (elf_section_flags (info->section) & SHF_PPC_VLE) != 0)
-- 
2.7.4