[PATCH] autoboot: fix illegal memory access when stop key and delay key are empty

[Yuezhang.Mo]

If both stop key and delay key are empty, the length of these
keys is 0. The subtraction operation will cause the u_int type
variable to overflow, will cause illegal memory access in key
input loop.

This commit fixes this bug by using int type instead of u_init.
---
 common/autoboot.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/common/autoboot.c b/common/autoboot.c
index e628baffb8..61fb09f910 100644
--- a/common/autoboot.c
+++ b/common/autoboot.c
@@ -156,9 +156,9 @@ static int passwd_abort_key(uint64_t etime)
        };
 
        char presskey[MAX_DELAY_STOP_STR];
-       u_int presskey_len = 0;
-       u_int presskey_max = 0;
-       u_int i;
+       int presskey_len = 0;
+       int presskey_max = 0;
+       int i;
 
 #  ifdef CONFIG_AUTOBOOT_DELAY_STR
        if (delaykey[0].str == NULL)
-- 
2.25.1