diff --git a/src/core/ipv4/icmp.c b/src/core/ipv4/icmp.c
index 0df7dd40..19c9b0fd 100644
--- a/src/core/ipv4/icmp.c
+++ b/src/core/ipv4/icmp.c
@@ -196,7 +196,7 @@ icmp_input(struct pbuf *p, struct netif *inp)
       ICMPH_TYPE_SET(iecho, ICMP_ER);
 #if CHECKSUM_GEN_ICMP
       /* adjust the checksum */
-      if (iecho->chksum >= PP_HTONS(0xffffU - (ICMP_ECHO << 8))) {
+      if (iecho->chksum > PP_HTONS(0xffffU - (ICMP_ECHO << 8))) {
         iecho->chksum += PP_HTONS(ICMP_ECHO << 8) + 1;
       } else {
         iecho->chksum += PP_HTONS(ICMP_ECHO << 8);