* coding.c: Integer and buffer overflow fixes.

(Funencodable_char_position, Fcheck_coding_systems_region)
(get_translation, handle_composition_annotation, consume_chars):
Use ptrdiff_t, not int, to avoid needless 32-bit limit on 64-bit hosts.
(consume_chars): Rewrite to avoid calculating an address outside buffer.

diff --git a/src/ChangeLog b/src/ChangeLog
index 696123c..a273fd6 100644 (file)
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -167,8 +167,10 @@
        Don't assume fixnums fit in int.
        (decode_coding_gap, decode_coding_object, encode_coding_object)
        (Fread_coding_system, Fdetect_coding_region)
-       (Funencodable_char_position, Fcheck_coding_systems_region):
+       (Funencodable_char_position, Fcheck_coding_systems_region)
+       (get_translation, handle_composition_annotation, consume_chars):
        Use ptrdiff_t, not int, to avoid needless 32-bit limit on 64-bit hosts.
+       (consume_chars): Rewrite to avoid calculating an address outside buffer.
        (Ffind_operation_coding_system): NATNUMP can eval its arg twice.
        (Fdefine_coding_system_internal): Check for charset-id overflow.
        (ENCODE_ISO_CHARACTER): Use unsigned, not int, to store the unsigned

diff --git a/src/coding.c b/src/coding.c
index 4450647..25ac0e9 100644 (file)
--- a/src/coding.c
+++ b/src/coding.c
@@ -6613,8 +6613,8 @@ get_translation (Lisp_Object trans, int *buf, int *buf_end)
     {
       Lisp_Object val = XCAR (trans);
       Lisp_Object from = XCAR (val);
-      int len = ASIZE (from);
-      int i;
+      ptrdiff_t len = ASIZE (from);
+      ptrdiff_t i;
 
       for (i = 0; i < len; i++)
        {
@@ -7132,7 +7132,7 @@ handle_composition_annotation (ptrdiff_t pos, ptrdiff_t limit,
          if (method != COMPOSITION_RELATIVE)
            {
              Lisp_Object components;
-             int len, i, i_byte;
+             ptrdiff_t i, len, i_byte;
 
              components = COMPOSITION_COMPONENTS (prop);
              if (VECTORP (components))
@@ -7303,7 +7303,7 @@ consume_chars (struct coding_system *coding, Lisp_Object translation_table,
        *buf++ = c;
       else
        {
-         int from_nchars = 1, to_nchars = 1;
+         ptrdiff_t from_nchars = 1, to_nchars = 1;
          int *lookup_buf_end;
          const unsigned char *p = src;
          int i;
@@ -7324,7 +7324,7 @@ consume_chars (struct coding_system *coding, Lisp_Object translation_table,
              else
                {
                  to_nchars = ASIZE (trans);
-                 if (buf + to_nchars > buf_end)
+                 if (buf_end - buf < to_nchars)
                    break;
                  c = XINT (AREF (trans, 0));
                }