More fixes for memory access errors triggered by attemps to examine corrupted binaries.

	PR binutils/17512
	* dwarf.c (display_block): Do nothing if the block starts after
	the end of the buffer.
	(read_and_display_attr_value): Add range checks.
	(struct Frame_Chunk): Make the ncols and ra fields unsigned.
	(frame_need_space): Test for an ncols of zero.
	(read_cie): Fail if the augmentation data extends off the end of
	the buffer.
	(display_debug_frames): Add checks for read_cie failing.  Add
	range checks.
	* coff-h8300.c (rtype2howto): Replace abort with returning a NULL
	value.
	* coff-h8500.c (rtype2howto): Likewise.
	* coff-tic30.c (rtype2howto): Likewise.
	* coff-z80.c (rtype2howto): Likewise.
	* coff-z8k.c (rtype2howto): Likewise.
	* coff-ia64.c (RTYPE2HOWTO): Always return a valid howto.
	* coff-m68k.c (m68k_rtype2howto): Return a NULL howto if none
	could be found.
	* coff-mcore.c (RTYPE2HOWTO): Add range checking.
	* coff-w65.c (rtype2howto): Likewise.
	* coff-we32k.c (RTYPE2HOWTO): Likewise.
	* pe-mips.c (RTYPE2HOWTO): Likewise.
	* coff-x86_64.c (coff_amd64_reloc): Likewise.  Replace abort with
	an error return.
	* coffcode.h (coff_slurp_reloc_table): Allow the rel parameter to
	be unused.
	* coffgen.c (make_a_section_from_file): Check the length of a
	section name before testing to see if it is a debug section name.
	(coff_object_p): Zero out any uninitialised bytes in the opt
	header.
	* ecoff.c (_bfd_ecoff_slurp_symbolic_info): Test for the raw
	source being empty when there are values to be processed.
	(_bfd_ecoff_slurp_symbol_table): Add range check.
	* mach-o.c (bfd_mach_o_canonicalize_one_reloc): Likewise.
	(bfd_mach_o_mangle_sections): Move test for too many sections to
	before the allocation of the section table.
	(bfd_mach_o_read_symtab_strtab): If the read fails, free the
	memory and nullify the symbol pointer.
	* reloc.c (bfd_generic_get_relocated_section_contents): Add
	handling of a bfd_reloc_notsupported return value.
	* versados.c (EDATA): Add range checking.
	(get_record): Likewise.
	(process_otr): Check for contents being available before updating
	them.
	(versados_canonicalize_reloc): Add range check.

1 files changed, 7 insertions, 2 deletions

diff --git a/bfd/coff-we32k.c b/bfd/coff-we32k.c
index d5481b8..b754815 100644
--- a/bfd/coff-we32k.c
+++ b/bfd/coff-we32k.c
@@ -53,14 +53,19 @@ static reloc_howto_type howto_table[] =
   HOWTO(R_PCRLONG,	       0,  2, 	32, TRUE,  0, complain_overflow_signed, 0, "DISP32",   TRUE, 0xffffffff,0xffffffff, FALSE),
 };
 
+#define NUM_HOWTOS (sizeof (howto_table) / sizeof (howto_table[0]))
+
 /* Turn a howto into a reloc  nunmber */
 
 #define SELECT_RELOC(x,howto) { x.r_type = howto->type; }
 #define BADMAG(x) WE32KBADMAG(x)
 #define WE32K	1
 
-#define RTYPE2HOWTO(cache_ptr, dst) \
-	    (cache_ptr)->howto = howto_table + (dst)->r_type;
+#define RTYPE2HOWTO(cache_ptr, dst)				\
+  ((cache_ptr)->howto =						\
+   ((dst)->r_type < NUM_HOWTOS					\
+    ? howto_table + (dst)->r_type				\
+    : NULL))
 
 #ifndef bfd_pe_print_pdata
 #define bfd_pe_print_pdata	NULL