udhcpc: ensure at least one unicast renew attempt

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 6 insertions, 4 deletions

diff --git a/networking/udhcp/d6_dhcpc.c b/networking/udhcp/d6_dhcpc.c
index 66e4b6c6a..e2f8a6a9c 100644
--- a/networking/udhcp/d6_dhcpc.c
+++ b/networking/udhcp/d6_dhcpc.c
@@ -1738,8 +1738,9 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
                                 /* 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;
+                                /* timeout > 60 - ensures at least one unicast renew attempt */
+                                if (timeout < 61)
+                                        timeout = 61;
                                 /* enter bound state */
                                 d6_run_script(packet.d6_options, packet_end,
                                         (state == REQUESTING ? "bound" : "renew"));
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index ab3e5a463..d2f165904 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -1725,8 +1725,9 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                         move_from_unaligned32(lease_seconds, temp);
                                         lease_seconds = ntohl(lease_seconds);
                                         /* paranoia: must not be too small and not prone to overflows */
-                                        if (lease_seconds < 0x10)
-                                                lease_seconds = 0x10;
+                                        /* timeout > 60 - ensures at least one unicast renew attempt */
+                                        if (lease_seconds < 2 * 61)
+                                                lease_seconds = 2 * 61;
                                         //if (lease_seconds > 0x7fffffff)
                                         //      lease_seconds = 0x7fffffff;
                                         //^^^not necessary since "timeout = lease_seconds / 2"