diff --git a/bpf_progs/offload.c b/bpf_progs/offload.c
index 4f152bf..3a713a0 100644
--- a/bpf_progs/offload.c
+++ b/bpf_progs/offload.c
@@ -593,7 +593,7 @@
 
     // Calculate the IPv4 one's complement checksum of the IPv4 header.
     __wsum sum4 = 0;
-    for (int i = 0; i < sizeof(*ip) / sizeof(__u16); ++i) {
+    for (unsigned i = 0; i < sizeof(*ip) / sizeof(__u16); ++i) {
         sum4 += ((__u16*)ip)[i];
     }
     // Note that sum4 is guaranteed to be non-zero by virtue of ip4->version == 4