asan : use of uninitialized value in buffer_and_nest

	* macro.c (buffer_and_nest): Don't read past end of string buffer.

diff --git a/gas/macro.c b/gas/macro.c
index 9327a6dea76dd4dc208ebe7caf91ac8ff01ee1c2..cbb9574fd667ab45fe8036d7ba4d7012fb788c58 100644 (file)
--- a/gas/macro.c
+++ b/gas/macro.c
@@ -184,14 +184,24 @@ buffer_and_nest (const char *from, const char *to, sb *ptr,
        {
          if (! flag_m68k_mri && ptr->ptr[i] == '.')
            i++;
-         if (from == NULL
-            && strncasecmp (ptr->ptr + i, "IRPC", from_len = 4) != 0
-            && strncasecmp (ptr->ptr + i, "IRP", from_len = 3) != 0
-            && strncasecmp (ptr->ptr + i, "IREPC", from_len = 5) != 0
-            && strncasecmp (ptr->ptr + i, "IREP", from_len = 4) != 0
-            && strncasecmp (ptr->ptr + i, "REPT", from_len = 4) != 0
-            && strncasecmp (ptr->ptr + i, "REP", from_len = 3) != 0)
-           from_len = 0;
+         if (from == NULL)
+           {
+             size_t len = ptr->len - i;
+             if (len >= 5 && strncasecmp (ptr->ptr + i, "IREPC", 5) == 0)
+               from_len = 5;
+             else if (len >= 4 && strncasecmp (ptr->ptr + i, "IREP", 4) == 0)
+               from_len = 4;
+             else if (len >= 4 && strncasecmp (ptr->ptr + i, "IRPC", 4) == 0)
+               from_len = 4;
+             else if (len >= 4 && strncasecmp (ptr->ptr + i, "REPT", 4) == 0)
+               from_len = 4;
+             else if (len >= 3 && strncasecmp (ptr->ptr + i, "IRP", 3) == 0)
+               from_len = 3;
+             else if (len >= 3 && strncasecmp (ptr->ptr + i, "REP", 3) == 0)
+               from_len = 3;
+             else
+               from_len = 0;
+           }
          if ((from != NULL
               ? strncasecmp (ptr->ptr + i, from, from_len) == 0
               : from_len > 0)
@@ -199,7 +209,8 @@ buffer_and_nest (const char *from, const char *to, sb *ptr,
                  || ! (is_part_of_name (ptr->ptr[i + from_len])
                        || is_name_ender (ptr->ptr[i + from_len]))))
            depth++;
-         if (strncasecmp (ptr->ptr + i, to, to_len) == 0
+         if (ptr->len - i >= to_len
+             && strncasecmp (ptr->ptr + i, to, to_len) == 0
              && (ptr->len == (i + to_len)
                  || ! (is_part_of_name (ptr->ptr[i + to_len])
                        || is_name_ender (ptr->ptr[i + to_len]))))