6.6-stable review patch. If anyone has any objections, please let me know.
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From: Namjae Jeon linkinjeon@kernel.org
commit 3aa660c059240e0c795217182cf7df32909dd917 upstream.
ksmbd_work could be freed when after connection release. Increment r_count of ksmbd_conn to indicate that requests are not finished yet and to not release the connection.
Cc: stable@vger.kernel.org Reported-by: Norbert Szetei norbert@doyensec.com Tested-by: Norbert Szetei norbert@doyensec.com Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/smb/server/connection.c | 20 ++++++++++++++++++++ fs/smb/server/connection.h | 2 ++ fs/smb/server/oplock.c | 6 ++++++ fs/smb/server/server.c | 14 ++------------ 4 files changed, 30 insertions(+), 12 deletions(-)
--- a/fs/smb/server/connection.c +++ b/fs/smb/server/connection.c @@ -432,6 +432,26 @@ void ksmbd_conn_init_server_callbacks(st default_conn_ops.terminate_fn = ops->terminate_fn; }
+void ksmbd_conn_r_count_inc(struct ksmbd_conn *conn) +{ + atomic_inc(&conn->r_count); +} + +void ksmbd_conn_r_count_dec(struct ksmbd_conn *conn) +{ + /* + * Checking waitqueue to dropping pending requests on + * disconnection. waitqueue_active is safe because it + * uses atomic operation for condition. + */ + atomic_inc(&conn->refcnt); + if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q)) + wake_up(&conn->r_count_q); + + if (atomic_dec_and_test(&conn->refcnt)) + kfree(conn); +} + int ksmbd_conn_transport_init(void) { int ret; --- a/fs/smb/server/connection.h +++ b/fs/smb/server/connection.h @@ -168,6 +168,8 @@ int ksmbd_conn_transport_init(void); void ksmbd_conn_transport_destroy(void); void ksmbd_conn_lock(struct ksmbd_conn *conn); void ksmbd_conn_unlock(struct ksmbd_conn *conn); +void ksmbd_conn_r_count_inc(struct ksmbd_conn *conn); +void ksmbd_conn_r_count_dec(struct ksmbd_conn *conn);
/* * WARNING --- a/fs/smb/server/oplock.c +++ b/fs/smb/server/oplock.c @@ -634,6 +634,7 @@ static void __smb2_oplock_break_noti(str { struct smb2_oplock_break *rsp = NULL; struct ksmbd_work *work = container_of(wk, struct ksmbd_work, work); + struct ksmbd_conn *conn = work->conn; struct oplock_break_info *br_info = work->request_buf; struct smb2_hdr *rsp_hdr; struct ksmbd_file *fp; @@ -689,6 +690,7 @@ static void __smb2_oplock_break_noti(str
out: ksmbd_free_work_struct(work); + ksmbd_conn_r_count_dec(conn); }
/** @@ -723,6 +725,7 @@ static int smb2_oplock_break_noti(struct work->sess = opinfo->sess;
if (opinfo->op_state == OPLOCK_ACK_WAIT) { + ksmbd_conn_r_count_inc(conn); INIT_WORK(&work->work, __smb2_oplock_break_noti); ksmbd_queue_work(work);
@@ -744,6 +747,7 @@ static void __smb2_lease_break_noti(stru { struct smb2_lease_break *rsp = NULL; struct ksmbd_work *work = container_of(wk, struct ksmbd_work, work); + struct ksmbd_conn *conn = work->conn; struct lease_break_info *br_info = work->request_buf; struct smb2_hdr *rsp_hdr;
@@ -790,6 +794,7 @@ static void __smb2_lease_break_noti(stru
out: ksmbd_free_work_struct(work); + ksmbd_conn_r_count_dec(conn); }
/** @@ -829,6 +834,7 @@ static int smb2_lease_break_noti(struct work->sess = opinfo->sess;
if (opinfo->op_state == OPLOCK_ACK_WAIT) { + ksmbd_conn_r_count_inc(conn); INIT_WORK(&work->work, __smb2_lease_break_noti); ksmbd_queue_work(work); wait_for_break_ack(opinfo); --- a/fs/smb/server/server.c +++ b/fs/smb/server/server.c @@ -270,17 +270,7 @@ static void handle_ksmbd_work(struct wor
ksmbd_conn_try_dequeue_request(work); ksmbd_free_work_struct(work); - /* - * Checking waitqueue to dropping pending requests on - * disconnection. waitqueue_active is safe because it - * uses atomic operation for condition. - */ - atomic_inc(&conn->refcnt); - if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q)) - wake_up(&conn->r_count_q); - - if (atomic_dec_and_test(&conn->refcnt)) - kfree(conn); + ksmbd_conn_r_count_dec(conn); }
/** @@ -310,7 +300,7 @@ static int queue_ksmbd_work(struct ksmbd conn->request_buf = NULL;
ksmbd_conn_enqueue_request(work); - atomic_inc(&conn->r_count); + ksmbd_conn_r_count_inc(conn); /* update activity on connection */ conn->last_active = jiffies; INIT_WORK(&work->work, handle_ksmbd_work);