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Re: [rfc] Detect dwarf address size mismatch
On Wed, Jul 11, 2007 at 01:30:48PM -0700, Jim Blandy wrote:
> True. But I think the check should go after the switch in any case;
> there's no reason to only apply sanity checking to that one opcode.
Reasonable enough. I've checked in this version.
--
Daniel Jacobowitz
CodeSourcery
2007-07-17 Daniel Jacobowitz <dan@codesourcery.com>
* dwarf2read.c (dwarf_decode_lines): Detect address size mismatches.
Index: dwarf2read.c
===================================================================
RCS file: /cvs/src/src/gdb/dwarf2read.c,v
retrieving revision 1.227
diff -u -p -r1.227 dwarf2read.c
--- dwarf2read.c 22 Jun 2007 12:26:59 -0000 1.227
+++ dwarf2read.c 17 Jul 2007 12:45:22 -0000
@@ -6668,9 +6668,9 @@ static void
dwarf_decode_lines (struct line_header *lh, char *comp_dir, bfd *abfd,
struct dwarf2_cu *cu, struct partial_symtab *pst)
{
- gdb_byte *line_ptr;
+ gdb_byte *line_ptr, *extended_end;
gdb_byte *line_end;
- unsigned int bytes_read;
+ unsigned int bytes_read, extended_len;
unsigned char op_code, extended_op, adj_opcode;
CORE_ADDR baseaddr;
struct objfile *objfile = cu->objfile;
@@ -6745,8 +6745,9 @@ dwarf_decode_lines (struct line_header *
else switch (op_code)
{
case DW_LNS_extended_op:
- read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
+ extended_len = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
line_ptr += bytes_read;
+ extended_end = line_ptr + extended_len;
extended_op = read_1_byte (abfd, line_ptr);
line_ptr += 1;
switch (extended_op)
@@ -6792,6 +6793,15 @@ dwarf_decode_lines (struct line_header *
_("mangled .debug_line section"));
return;
}
+ /* Make sure that we parsed the extended op correctly. If e.g.
+ we expected a different address size than the producer used,
+ we may have read the wrong number of bytes. */
+ if (line_ptr != extended_end)
+ {
+ complaint (&symfile_complaints,
+ _("mangled .debug_line section"));
+ return;
+ }
break;
case DW_LNS_copy:
if (lh->num_file_names < file)