diff --git a/net/ipv6/rpl.c b/net/ipv6/rpl.c
index 488aec9e1a74..d1876f192225 100644
--- a/net/ipv6/rpl.c
+++ b/net/ipv6/rpl.c
@@ -32,7 +32,8 @@ static void *ipv6_rpl_segdata_pos(const struct ipv6_rpl_sr_hdr *hdr, int i)
 size_t ipv6_rpl_srh_size(unsigned char n, unsigned char cmpri,
 			 unsigned char cmpre)
 {
-	return (n * IPV6_PFXTAIL_LEN(cmpri)) + IPV6_PFXTAIL_LEN(cmpre);
+	return sizeof(struct ipv6_rpl_sr_hdr) + (n * IPV6_PFXTAIL_LEN(cmpri)) +
+		IPV6_PFXTAIL_LEN(cmpre);
 }
 
 void ipv6_rpl_srh_decompress(struct ipv6_rpl_sr_hdr *outhdr,