scripts/kconfig/nconf: fix memmove's length arg
authorCheng Renquan <crquan@gmail.com>
Thu, 1 Sep 2011 17:52:19 +0000 (10:52 -0700)
committerMichal Marek <mmarek@suse.cz>
Fri, 9 Sep 2011 12:40:08 +0000 (14:40 +0200)
In case KEY_BACKSPACE / KEY_DC to delete a char, it memmove only
(len-cursor_position+1) bytes;
the default case is to insert a char, it should also memmove exactly
(len-cursor_position+1) bytes;

the original use of (len+1) is wrong and may access following memory
that doesn't belong to result, may cause SegFault in theory;

case KEY_BACKSPACE:
if (cursor_position > 0) {
memmove(&result[cursor_position-1],
&result[cursor_position],
len-cursor_position+1);
cursor_position--;
}
break;
case KEY_DC:
if (cursor_position >= 0 && cursor_position < len) {
memmove(&result[cursor_position],
&result[cursor_position+1],
len-cursor_position+1);
}
break;
default:
if ((isgraph(res) || isspace(res)) &&
len-2 < result_len) {
/* insert the char at the proper position */
memmove(&result[cursor_position+1],
&result[cursor_position],
len-cursor_position+1);
result[cursor_position] = res;
cursor_position++;
}

Signed-off-by: Cheng Renquan <crquan@gmail.com>
Acked-by: Nir Tzachar <nir.tzachar@gmail.com>
scripts/kconfig/nconf.gui.c

index d3af04e95288bc974c527518c02e9f726b2a7317..3ce2a7c0bda6f846e2f9968d954abb0fedade438 100644 (file)
@@ -457,7 +457,7 @@ int dialog_inputbox(WINDOW *main_window,
                                /* insert the char at the proper position */
                                memmove(&result[cursor_position+1],
                                                &result[cursor_position],
-                                               len+1);
+                                               len-cursor_position+1);
                                result[cursor_position] = res;
                                cursor_position++;
                        } else {