From 1c21ea3fa43fca0c486e12eb9d0b0b371f1ad7fd Mon Sep 17 00:00:00 2001
From: Namjae Jeon <linkinjeon@kernel.org>
Date: Thu, 29 Aug 2024 17:34:43 +0900
Subject: [PATCH] ksmbd: add refcnt to ksmbd_conn struct

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
---
 connection.c |  4 +++-
 connection.h |  1 +
 oplock.c     | 28 +++++++++-------------------
 3 files changed, 13 insertions(+), 20 deletions(-)

diff --git a/connection.c b/connection.c
index d0554836..c32fb46d 100644
--- a/connection.c
+++ b/connection.c
@@ -42,7 +42,8 @@ void ksmbd_conn_free(struct ksmbd_conn *conn)
 	xa_destroy(&conn->sessions);
 	kvfree(conn->request_buf);
 	kfree(conn->preauth_info);
-	kfree(conn);
+	if (atomic_dec_and_test(&conn->refcnt))
+		kfree(conn);
 }
 
 /**
@@ -75,6 +76,7 @@ struct ksmbd_conn *ksmbd_conn_alloc(void)
 		conn->um = NULL;
 	atomic_set(&conn->req_running, 0);
 	atomic_set(&conn->r_count, 0);
+	atomic_set(&conn->refcnt, 1);
 	conn->total_credits = 1;
 	conn->outstanding_credits = 0;
 
diff --git a/connection.h b/connection.h
index 5b947175..b379ae4f 100644
--- a/connection.h
+++ b/connection.h
@@ -106,6 +106,7 @@ struct ksmbd_conn {
 	bool				signing_negotiated;
 	__le16				signing_algorithm;
 	bool				binding;
+	atomic_t			refcnt;
 };
 
 struct ksmbd_conn_ops {
diff --git a/oplock.c b/oplock.c
index 10e16e2a..ff5fa92c 100644
--- a/oplock.c
+++ b/oplock.c
@@ -57,6 +57,7 @@ static struct oplock_info *alloc_opinfo(struct ksmbd_work *work,
 	init_waitqueue_head(&opinfo->oplock_brk);
 	atomic_set(&opinfo->refcount, 1);
 	atomic_set(&opinfo->breaking_cnt, 0);
+	atomic_inc(&opinfo->conn->refcnt);
 
 	return opinfo;
 }
@@ -130,6 +131,8 @@ static void free_opinfo(struct oplock_info *opinfo)
 {
 	if (opinfo->is_lease)
 		free_lease(opinfo);
+	if (atomic_dec_and_test(&opinfo->conn->refcnt))
+		kfree(opinfo->conn);
 	kfree(opinfo);
 }
 
@@ -155,8 +158,7 @@ static struct oplock_info *opinfo_get_list(struct ksmbd_inode *ci)
 	opinfo = list_first_entry(&ci->m_op_list, struct oplock_info,
 					op_entry);
 	if (opinfo) {
-		if (opinfo->conn == NULL ||
-		    !atomic_inc_not_zero(&opinfo->refcount))
+		if (!atomic_inc_not_zero(&opinfo->refcount))
 			opinfo = NULL;
 		else {
 			atomic_inc(&opinfo->conn->r_count);
@@ -1320,7 +1322,7 @@ void smb_send_parent_lease_break_noti(struct ksmbd_file *fp,
 
 	down_read(&p_ci->m_lock);
 	list_for_each_entry(opinfo, &p_ci->m_op_list, op_entry) {
-		if (opinfo->conn == NULL || !opinfo->is_lease)
+		if (!opinfo->is_lease)
 			continue;
 
 		if (opinfo->o_lease->state != SMB2_OPLOCK_LEVEL_NONE &&
@@ -1330,11 +1332,8 @@ void smb_send_parent_lease_break_noti(struct ksmbd_file *fp,
 			if (!atomic_inc_not_zero(&opinfo->refcount))
 				continue;
 
-			atomic_inc(&opinfo->conn->r_count);
-			if (ksmbd_conn_releasing(opinfo->conn)) {
-				atomic_dec(&opinfo->conn->r_count);
+			if (ksmbd_conn_releasing(opinfo->conn))
 				continue;
-			}
 
 			oplock_break(opinfo, SMB2_OPLOCK_LEVEL_NONE);
 			opinfo_conn_put(opinfo);
@@ -1361,18 +1360,15 @@ void smb_lazy_parent_lease_break_close(struct ksmbd_file *fp)
 
 	down_read(&p_ci->m_lock);
 	list_for_each_entry(opinfo, &p_ci->m_op_list, op_entry) {
-		if (opinfo->conn == NULL || !opinfo->is_lease)
+		if (!opinfo->is_lease)
 			continue;
 
 		if (opinfo->o_lease->state != SMB2_OPLOCK_LEVEL_NONE) {
 			if (!atomic_inc_not_zero(&opinfo->refcount))
 				continue;
 
-			atomic_inc(&opinfo->conn->r_count);
-			if (ksmbd_conn_releasing(opinfo->conn)) {
-				atomic_dec(&opinfo->conn->r_count);
+			if (ksmbd_conn_releasing(opinfo->conn))
 				continue;
-			}
 			oplock_break(opinfo, SMB2_OPLOCK_LEVEL_NONE);
 			opinfo_conn_put(opinfo);
 		}
@@ -1571,17 +1567,11 @@ void smb_break_all_levII_oplock(struct ksmbd_work *work, struct ksmbd_file *fp,
 
 	down_read(&ci->m_lock);
 	list_for_each_entry(brk_op, &ci->m_op_list, op_entry) {
-		if (brk_op->conn == NULL)
-			continue;
-
 		if (!atomic_inc_not_zero(&brk_op->refcount))
 			continue;
 
-		atomic_inc(&brk_op->conn->r_count);
-		if (ksmbd_conn_releasing(brk_op->conn)) {
-			atomic_dec(&brk_op->conn->r_count);
+		if (ksmbd_conn_releasing(brk_op->conn))
 			continue;
-		}
 
 #ifdef CONFIG_SMB_INSECURE_SERVER
 		if (brk_op->is_smb2) {