6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Namjae Jeon <linkinjeon@xxxxxxxxxx>
commit 0a77715db22611df50b178374c51e2ba0d58866e upstream.
There is a race condition between ksmbd_smb2_session_create and
ksmbd_expire_session. This patch add missing sessions_table_lock
while adding/deleting session from global session table.
Cc: stable@xxxxxxxxxxxxxxx # v5.15+
Reported-by: Norbert Szetei <norbert@xxxxxxxxxxxx>
Tested-by: Norbert Szetei <norbert@xxxxxxxxxxxx>
Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/smb/server/mgmt/user_session.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/fs/smb/server/mgmt/user_session.c
+++ b/fs/smb/server/mgmt/user_session.c
@@ -174,6 +174,7 @@ static void ksmbd_expire_session(struct
unsigned long id;
struct ksmbd_session *sess;
+ down_write(&sessions_table_lock);
down_write(&conn->session_lock);
xa_for_each(&conn->sessions, id, sess) {
if (atomic_read(&sess->refcnt) == 0 &&
@@ -187,6 +188,7 @@ static void ksmbd_expire_session(struct
}
}
up_write(&conn->session_lock);
+ up_write(&sessions_table_lock);
}
int ksmbd_session_register(struct ksmbd_conn *conn,
@@ -228,7 +230,6 @@ void ksmbd_sessions_deregister(struct ks
}
}
}
- up_write(&sessions_table_lock);
down_write(&conn->session_lock);
xa_for_each(&conn->sessions, id, sess) {
@@ -248,6 +249,7 @@ void ksmbd_sessions_deregister(struct ks
}
}
up_write(&conn->session_lock);
+ up_write(&sessions_table_lock);
}
struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
