commit 1b8d0300a3e9 ("scsi: libiscsi: Fix UAF in
iscsi_conn_get_param()/iscsi_conn_teardown()") fixed an UAF in
iscsi_conn_get_param() and introduced 2 tmp_xxx varibles, the
implement looks ugly.We can fix this UAF with the help of device_del() gracefully. Call iscsi_remove_conn() at the beginning of iscsi_conn_teardown would make userspace unable to see iscsi_cls_conn any more, then we can free memory safely. Signed-off-by: Wenchao Hao <[email protected]> Signed-off-by: Wu Bo <[email protected]> --- drivers/scsi/libiscsi.c | 8 ++++---- drivers/scsi/scsi_transport_iscsi.c | 3 ++- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index 43f903bce0b8..0d57521751dd 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -3109,8 +3109,8 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn) { struct iscsi_conn *conn = cls_conn->dd_data; struct iscsi_session *session = conn->session; - char *tmp_persistent_address = conn->persistent_address; - char *tmp_local_ipaddr = conn->local_ipaddr; + + iscsi_remove_conn(cls_conn); del_timer_sync(&conn->transport_timer); @@ -3132,6 +3132,8 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn) spin_lock_bh(&session->frwd_lock); free_pages((unsigned long) conn->data, get_order(ISCSI_DEF_MAX_RECV_SEG_LEN)); + kfree(conn->persistent_address); + kfree(conn->local_ipaddr); /* regular RX path uses back_lock */ spin_lock_bh(&session->back_lock); kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task, @@ -3143,8 +3145,6 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn) mutex_unlock(&session->eh_mutex); iscsi_destroy_conn(cls_conn); - kfree(tmp_persistent_address); - kfree(tmp_local_ipaddr); } EXPORT_SYMBOL_GPL(iscsi_conn_teardown); diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index ca724eed4f4d..7b4d998708e7 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -2165,6 +2165,7 @@ static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data) { if (!iscsi_is_conn_dev(dev)) return 0; + iscsi_remove_conn(iscsi_dev_to_conn(dev)); return iscsi_destroy_conn(iscsi_dev_to_conn(dev)); } @@ -2463,7 +2464,7 @@ int iscsi_destroy_conn(struct iscsi_cls_conn *conn) transport_unregister_device(&conn->dev); ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n"); - device_unregister(&conn->dev); + iscsi_free_conn(conn); return 0; } EXPORT_SYMBOL_GPL(iscsi_destroy_conn); -- 2.32.0 -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/open-iscsi/20220309030916.2932316-4-haowenchao%40huawei.com.
