diff --git a/src/ie.c b/src/ie.c
index 4c3d4069..de030a76 100644
--- a/src/ie.c
+++ b/src/ie.c
@@ -163,7 +163,7 @@ static void *ie_tlv_vendor_ie_concat(const unsigned char oui[],
  * Elements (the order of these elements in the original packet shall be
  * preserved when concatenating Data components)."
  */
-void *ie_tlv_extract_wsc_payload(const unsigned char *ies, unsigned int len,
+void *ie_tlv_extract_wsc_payload(const unsigned char *ies, size_t len,
 							ssize_t *out_len)
 {
 	static unsigned char oui[3] = { 0x00, 0x50, 0xf2 };
diff --git a/src/ie.h b/src/ie.h
index 52cd3c11..2fc8c2e3 100644
--- a/src/ie.h
+++ b/src/ie.h
@@ -251,7 +251,7 @@ static inline const unsigned char *ie_tlv_iter_get_data(
 	return iter->data;
 }
 
-void *ie_tlv_extract_wsc_payload(const unsigned char *ies, unsigned int len,
+void *ie_tlv_extract_wsc_payload(const uint8_t *ies, size_t len,
 							ssize_t *out_len);
 
 bool ie_tlv_builder_init(struct ie_tlv_builder *builder);