libbacktrace: correct buffer overflow tests

	* dwarf.c (resolve_string): Use > rather than >= to check whether
	string index extends past buffer.
	(resolve_addr_index): Similarly for address index.

diff --git a/libbacktrace/dwarf.c b/libbacktrace/dwarf.c
index 582f34bc816b27b305e805507d1967182d33b127..0c913c95983b2d9f90a4276934817bc3765d9c66 100644 (file)
--- a/libbacktrace/dwarf.c
+++ b/libbacktrace/dwarf.c
@@ -1053,7 +1053,7 @@ resolve_string (const struct dwarf_sections *dwarf_sections, int is_dwarf64,
 
        offset = val->u.uint * (is_dwarf64 ? 8 : 4) + str_offsets_base;
        if (offset + (is_dwarf64 ? 8 : 4)
-           >= dwarf_sections->size[DEBUG_STR_OFFSETS])
+           > dwarf_sections->size[DEBUG_STR_OFFSETS])
          {
            error_callback (data, "DW_FORM_strx value out of range", 0);
            return 0;
@@ -1097,7 +1097,7 @@ resolve_addr_index (const struct dwarf_sections *dwarf_sections,
   struct dwarf_buf addr_buf;
 
   offset = addr_index * addrsize + addr_base;
-  if (offset + addrsize >= dwarf_sections->size[DEBUG_ADDR])
+  if (offset + addrsize > dwarf_sections->size[DEBUG_ADDR])
     {
       error_callback (data, "DW_FORM_addrx value out of range", 0);
       return 0;