udhcpc: fix OPTION_6RD parsing (could overflow its malloced buffer)
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 48097bc..2fe84e1 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -113,7 +113,7 @@
[OPTION_IP ] = sizeof("255.255.255.255 "),
[OPTION_IP_PAIR ] = sizeof("255.255.255.255 ") * 2,
[OPTION_STATIC_ROUTES ] = sizeof("255.255.255.255/32 255.255.255.255 "),
- [OPTION_6RD ] = sizeof("32 128 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff 255.255.255.255 "),
+ [OPTION_6RD ] = sizeof("132 128 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff 255.255.255.255 "),
[OPTION_STRING ] = 1,
[OPTION_STRING_HOST ] = 1,
#if ENABLE_FEATURE_UDHCP_RFC3397
@@ -222,7 +222,7 @@
type = optflag->flags & OPTION_TYPE_MASK;
optlen = dhcp_option_lengths[type];
upper_length = len_of_option_as_string[type]
- * ((unsigned)(len + optlen - 1) / (unsigned)optlen);
+ * ((unsigned)(len + optlen) / (unsigned)optlen);
dest = ret = xmalloc(upper_length + strlen(opt_name) + 2);
dest += sprintf(ret, "%s=", opt_name);