commit 53a556cb4a705f4eae2bcb49552b6427b231378a
Author: ABC <abc@telekom.ru>
Date:   Mon Aug 14 22:55:25 2017 +0300

    Compatibility with kernel 4.13.
    
    Offset patch torvalds/linux@14afee4b6092fde451ee17604e5f5c89da33e71e

diff --git a/compat.h b/compat.h
index 061eb57..275ff58 100644
--- a/compat.h
+++ b/compat.h
@@ -636,4 +636,10 @@ static inline unsigned int xt_hooknum(const struct xt_action_param *par)
 # define SK_CAN_REUSE   1
 #endif
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4,13,0)
+# define compat_refcount_read atomic_read
+#else
+# define compat_refcount_read refcount_read
+#endif
+
 #endif /* COMPAT_NETFLOW_H */
diff --git a/ipt_NETFLOW.c b/ipt_NETFLOW.c
index 494ea74..9365325 100644
--- a/ipt_NETFLOW.c
+++ b/ipt_NETFLOW.c
@@ -622,7 +622,7 @@ static int snmp_seq_show(struct seq_file *seq, void *v)
 
 			seq_printf(seq, " %u %u %u\n",
 			    sk->sk_sndbuf,
-			    atomic_read(&sk->sk_wmem_alloc),
+			    compat_refcount_read(&sk->sk_wmem_alloc),
 			    wmem_peak);
 		} else
 			seq_printf(seq, " 0 0 %u\n", wmem_peak);
@@ -864,7 +864,7 @@ static int nf_seq_show(struct seq_file *seq, void *v)
 			seq_printf(seq, ", sndbuf %u, filled %u, peak %u;"
 			    " err: sndbuf reached %u, connect %u, cberr %u, other %u\n",
 			    sk->sk_sndbuf,
-			    atomic_read(&sk->sk_wmem_alloc),
+			    compat_refcount_read(&sk->sk_wmem_alloc),
 			    atomic_read(&usock->wmem_peak),
 			    usock->err_full,
 			    usock->err_connect,
@@ -2031,7 +2031,7 @@ static void netflow_sendmsg(void *buffer, const int len)
 			printk(KERN_INFO "netflow_sendmsg: sendmsg(%d, %d) [%u %u]\n",
 			       snum,
 			       len,
-			       atomic_read(&usock->sock->sk->sk_wmem_alloc),
+			       compat_refcount_read(&usock->sock->sk->sk_wmem_alloc),
 			       usock->sock->sk->sk_sndbuf);
 		ret = kernel_sendmsg(usock->sock, &msg, &iov, 1, (size_t)len);
 		if (ret < 0) {
@@ -2054,7 +2054,7 @@ static void netflow_sendmsg(void *buffer, const int len)
 			printk(KERN_ERR "ipt_NETFLOW: sendmsg[%d] error %d: data loss %llu pkt, %llu bytes%s\n",
 			       snum, ret, pdu_packets, pdu_traf, suggestion);
 		} else {
-			unsigned int wmem = atomic_read(&usock->sock->sk->sk_wmem_alloc);
+			unsigned int wmem = compat_refcount_read(&usock->sock->sk->sk_wmem_alloc);
 			if (wmem > atomic_read(&usock->wmem_peak))
 				atomic_set(&usock->wmem_peak, wmem);
 			NETFLOW_STAT_INC(exported_pkt);