From 58e7504a3c532832a7753f530efa3b96adfc0807 Mon Sep 17 00:00:00 2001
From: Anthony Hayward <anthayward@microsoft.com>
Date: Tue, 6 Sep 2022 08:16:24 +0100
Subject: [PATCH] Add hash_remove and use in transp to fix #261

---
 include/re_hash.h |  1 +
 src/hash/hash.c   | 17 +++++++++++++++++
 src/sip/transp.c  |  6 +-----
 3 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/include/re_hash.h b/include/re_hash.h
index 8858dbcb..8ba2a4f3 100644
--- a/include/re_hash.h
+++ b/include/re_hash.h
@@ -12,6 +12,7 @@ struct pl;
 int  hash_alloc(struct hash **hp, uint32_t bsize);
 void hash_append(struct hash *h, uint32_t key, struct le *le, void *data);
 void hash_unlink(struct le *le);
+void hash_remove(struct le *le);
 struct le *hash_lookup(const struct hash *h, uint32_t key, list_apply_h *ah,
 		       void *arg);
 struct le *hash_apply(const struct hash *h, list_apply_h *ah, void *arg);
diff --git a/src/hash/hash.c b/src/hash/hash.c
index 45aa11e3..32d1cc14 100644
--- a/src/hash/hash.c
+++ b/src/hash/hash.c
@@ -95,6 +95,23 @@ void hash_unlink(struct le *le)
 }
 
 
+/**
+ * If the element is present in the hashmap table, unlink it and deref the object,
+ * otherwise do nothing.  This is like hash_flush but for a single entry.
+ *
+ * @param le     List element
+ */
+void hash_remove(struct le *le)
+{
+	if (le->list != NULL)
+	{
+		void *data = le->data;
+		list_unlink(le);
+		mem_deref(data);
+	}
+}
+
+
 /**
  * Apply a handler function to all elements in the hashmap with a matching key
  *
diff --git a/src/sip/transp.c b/src/sip/transp.c
index aed33bb0..625b650f 100644
--- a/src/sip/transp.c
+++ b/src/sip/transp.c
@@ -175,7 +175,6 @@ static void conn_close(struct sip_conn *conn, int err)
 	conn->tc = mem_deref(conn->tc);
 	tmr_cancel(&conn->tmr_ka);
 	tmr_cancel(&conn->tmr);
-	hash_unlink(&conn->he);
 
 	le = list_head(&conn->ql);
 
@@ -195,6 +194,7 @@ static void conn_close(struct sip_conn *conn, int err)
 	}
 
 	sip_keepalive_signal(&conn->kal, err);
+	hash_remove(&conn->he);
 }
 
 
@@ -203,7 +203,6 @@ static void conn_tmr_handler(void *arg)
 	struct sip_conn *conn = arg;
 
 	conn_close(conn, ETIMEDOUT);
-	mem_deref(conn);
 }
 
 
@@ -221,7 +220,6 @@ static void conn_keepalive_handler(void *arg)
 	err = tcp_send(conn->tc, &mb);
 	if (err) {
 		conn_close(conn, err);
-		mem_deref(conn);
 		return;
 	}
 
@@ -448,7 +446,6 @@ static void tcp_recv_handler(struct mbuf *mb, void *arg)
  out:
 	if (err) {
 		conn_close(conn, err);
-		mem_deref(conn);
 	}
 }
 
@@ -492,7 +489,6 @@ static void tcp_close_handler(int err, void *arg)
 	struct sip_conn *conn = arg;
 
 	conn_close(conn, err ? err : ECONNRESET);
-	mem_deref(conn);
 }