2 files changed, 10 insertions, 13 deletions

diff --git a/networking/udhcp/d6_dhcpc.c b/networking/udhcp/d6_dhcpc.c
index 460f3d9a4..f3a7b827c 100644
--- a/networking/udhcp/d6_dhcpc.c
+++ b/networking/udhcp/d6_dhcpc.c
@@ -1465,8 +1465,8 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
                         if (packet.d6_msg_type == D6_MSG_REPLY) {
                                 uint32_t lease_seconds;
                                 struct d6_option *option;
-                                int address_timeout;
-                                int prefix_timeout;
+                                unsigned address_timeout;
+                                unsigned prefix_timeout;
  type_is_ok:
                                 address_timeout = 0;
                                 prefix_timeout = 0;
@@ -1626,12 +1626,9 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
                                         move_from_unaligned32(lease_seconds, iaaddr->data + 16 + 4);
                                         lease_seconds = ntohl(lease_seconds);
 /// TODO: check for 0 lease time?
-                                        /* paranoia: must not be prone to overflows */
-                                        if (lease_seconds > 0x7fffffff / 1000)
-                                                lease_seconds = 0x7fffffff / 1000;
-                                        address_timeout = lease_seconds / 2;
                                         bb_error_msg("%s obtained, lease time %u",
                                                 "IPv6", /*inet_ntoa(temp_addr),*/ (unsigned)lease_seconds);
+                                        address_timeout = lease_seconds;
                                 }
                                 if (option_mask32 & OPT_d) {
                                         struct d6_option *iaprefix;
@@ -1662,18 +1659,16 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
                                         }
                                         move_from_unaligned32(lease_seconds, iaprefix->data + 4);
                                         lease_seconds = ntohl(lease_seconds);
-                                        /* paranoia: must not be prone to overflows */
-                                        if (lease_seconds > 0x7fffffff / 1000)
-                                                lease_seconds = 0x7fffffff / 1000;
-                                        prefix_timeout = lease_seconds / 2;
                                         bb_error_msg("%s obtained, lease time %u",
                                                 "prefix", /*inet_ntoa(temp_addr),*/ (unsigned)lease_seconds);
+                                        prefix_timeout = lease_seconds;
                                 }
                                 if (!address_timeout)
                                         address_timeout = prefix_timeout;
                                 if (!prefix_timeout)
                                         prefix_timeout = address_timeout;
-                                timeout = address_timeout > prefix_timeout ? prefix_timeout : address_timeout;
+                                /* note: "int timeout" will not overflow even with 0xffffffff inputs here: */
+                                timeout = (prefix_timeout < address_timeout ? prefix_timeout : address_timeout) / 2;
                                 /* paranoia: must not be too small */
                                 if (timeout < 0x10)
                                         timeout = 0x10;
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 55f21c187..385fc4998 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -1732,8 +1732,10 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                         /* paranoia: must not be too small and not prone to overflows */
                                         if (lease_seconds < 0x10)
                                                 lease_seconds = 0x10;
-                                        if (lease_seconds > 0x7fffffff / 1000)
-                                                lease_seconds = 0x7fffffff / 1000;
+                                        //if (lease_seconds > 0x7fffffff)
+                                        //      lease_seconds = 0x7fffffff;
+                                        //^^^not necessary since "timeout = lease_seconds / 2"
+                                        //does not overflow even for 0xffffffff.
                                 }
 #if ENABLE_FEATURE_UDHCPC_ARPING
                                 if (opt & OPT_a) {