readelf: DW_OP_call_ref and DW_OP_GNU_implicit_pointer are invalid for CFA.

print_cfa_program might call print_ops with zero offset size. We don't
need (and don't know) the DWARF offset size in that case. DW_OP_call_ref
and DW_OP_GNU_implicit_pointer need to know the offset size because they
reference a DIE. But they are invalid when used from CFA.

Signed-off-by: Mark Wielaard <mjw@redhat.com>

diff --git a/src/ChangeLog b/src/ChangeLog
index c149a9c..ccbd6e8 100644 (file)
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2014-12-07  Mark Wielaard  <mjw@redhat.com>
+
+       * readelf.c (print_ops): Handle zero ref_size for DW_OP_call_ref
+       and DW_OP_GNU_implicit_pointer.
+
 2014-12-04  Mark Wielaard  <mjw@redhat.com>
 
        * objdump.c (show_relocs_x): Make sure destshdr exists.

diff --git a/src/readelf.c b/src/readelf.c
index 89b1754..881bb45 100644 (file)
--- a/src/readelf.c
+++ b/src/readelf.c
@@ -3999,6 +3999,8 @@ print_ops (Dwfl_Module *dwflmod, Dwarf *dbg, int indent, int indentrest,
 
        case DW_OP_call_ref:
          /* Offset operand.  */
+         if (ref_size == 0)
+           goto invalid; /* Cannot be used in CFA.  */
          NEED (ref_size);
          if (ref_size == 4)
            addr = read_4ubyte_unaligned (dbg, data);
@@ -4203,6 +4205,8 @@ print_ops (Dwfl_Module *dwflmod, Dwarf *dbg, int indent, int indentrest,
          /* DIE offset operand.  */
          start = data;
          NEED (ref_size + 1);
+         if (ref_size == 0)
+           goto invalid; /* Cannot be used in CFA.  */
          if (ref_size == 4)
            addr = read_4ubyte_unaligned (dbg, data);
          else