scripts/kconfig/nconf: fix memmove's length arg
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>
diff --git a/scripts/kconfig/nconf.gui.c b/scripts/kconfig/nconf.gui.c
index d3af04e..3ce2a7c 100644
--- a/scripts/kconfig/nconf.gui.c
+++ b/scripts/kconfig/nconf.gui.c
@@ -457,7 +457,7 @@
/* 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 {