diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 288693981b00..5d2587cd1920 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -4704,6 +4704,7 @@ int tcp_abort(struct sock *sk, int err)
 	bh_unlock_sock(sk);
 	local_bh_enable();
 	tcp_write_queue_purge(sk);
+	printk("%s, %p\n", __func__, sk);
 	release_sock(sk);
 	return 0;
 }
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index ea370afa70ed..562fb2b89494 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1246,6 +1246,7 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
 			md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk));
 			rcu_assign_pointer(tp->md5sig_info, NULL);
 			kfree_rcu(md5sig, rcu);
+			printk("%s, %p \n", __func__, md5sig);
 			return -EUSERS;
 		}
 	}
@@ -1271,6 +1272,7 @@ int tcp_md5_key_copy(struct sock *sk, const union tcp_md5_addr *addr,
 			md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk));
 			net_warn_ratelimited("Too many TCP-MD5 keys in the system\n");
 			rcu_assign_pointer(tp->md5sig_info, NULL);
+			printk("%s, %p \n", __func__, md5sig);
 			kfree_rcu(md5sig, rcu);
 			return -EUSERS;
 		}
@@ -1292,6 +1294,7 @@ int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family,
 		return -ENOENT;
 	hlist_del_rcu(&key->node);
 	atomic_sub(sizeof(*key), &sk->sk_omem_alloc);
+	printk("%s, %p \n", __func__, key);
 	kfree_rcu(key, rcu);
 	return 0;
 }
@@ -1309,6 +1312,7 @@ static void tcp_clear_md5_list(struct sock *sk)
 	hlist_for_each_entry_safe(key, n, &md5sig->head, node) {
 		hlist_del_rcu(&key->node);
 		atomic_sub(sizeof(*key), &sk->sk_omem_alloc);
+		printk("%s, %p \n", __func__, key);
 		kfree_rcu(key, rcu);
 	}
 }
@@ -2310,9 +2314,12 @@ void tcp_v4_destroy_sock(struct sock *sk)
 #ifdef CONFIG_TCP_MD5SIG
 	/* Clean up the MD5 key list, if any */
 	if (tp->md5sig_info) {
+		struct tcp_md5sig_info *md5sig;
 		tcp_clear_md5_list(sk);
-		kfree_rcu(rcu_dereference_protected(tp->md5sig_info, 1), rcu);
-		tp->md5sig_info = NULL;
+		md5sig = rcu_dereference_protected(tp->md5sig_info, 1);
+		printk("%s, %p, %p \n", __func__, tp->md5sig_info, md5sig);
+		rcu_assign_pointer(tp->md5sig_info, NULL);
+		kfree_rcu(md5sig, rcu);
 		static_branch_slow_dec_deferred(&tcp_md5_needed);
 	}
 #endif
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 71d01cf3c13e..1c0c50027c48 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1091,6 +1091,7 @@ void tcp_release_cb(struct sock *sk)
 		tcp_tsq_write(sk);
 		__sock_put(sk);
 	}
+	printk("%p, %s\n", sk, __func__);
 	/* Here begins the tricky part :
 	 * We are called from release_sock() with :
 	 * 1) BH disabled