6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ze Tan [ Upstream commit 99b25b046e47e4904373cfeb445c5483f1633d88 ] See the procedure below: smb2_sess_setup ksmbd_smb2_session_create __session_create atomic_set(&sess->refcnt, 2) hash_add(sessions_table, &sess->hlist, sess->id) ksmbd_session_register xa_store(&conn->sessions, sess->id, sess) // fail ksmbd_user_session_put atomic_dec(&sess->refcnt) // refcnt is 1, session is not freed Remove the session from sessions_table and drop its table reference if xa_store() fails. Fixes: f5c779b7ddbd ("ksmbd: fix racy issue from session setup and logoff") Signed-off-by: Ze Tan Reviewed-by: ChenXiaoSong Signed-off-by: Namjae Jeon Signed-off-by: Sasha Levin --- fs/smb/server/mgmt/user_session.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/smb/server/mgmt/user_session.c b/fs/smb/server/mgmt/user_session.c index 26c1bfff242a5..3c10a928e325a 100644 --- a/fs/smb/server/mgmt/user_session.c +++ b/fs/smb/server/mgmt/user_session.c @@ -212,10 +212,20 @@ static void ksmbd_expire_session(struct ksmbd_conn *conn) int ksmbd_session_register(struct ksmbd_conn *conn, struct ksmbd_session *sess) { + int ret; + sess->dialect = conn->dialect; memcpy(sess->ClientGUID, conn->ClientGUID, SMB2_CLIENT_GUID_SIZE); ksmbd_expire_session(conn); - return xa_err(xa_store(&conn->sessions, sess->id, sess, GFP_KERNEL)); + ret = xa_err(xa_store(&conn->sessions, sess->id, sess, GFP_KERNEL)); + if (ret) { + down_write(&sessions_table_lock); + hash_del(&sess->hlist); + up_write(&sessions_table_lock); + ksmbd_user_session_put(sess); + } + + return ret; } static int ksmbd_chann_del(struct ksmbd_conn *conn, struct ksmbd_session *sess) -- 2.53.0