projects/linux·commit 1b8d0300

scsi: libiscsi: Fix UAF in iscsi_conn_get_param()/iscsi_conn_teardown()

1b8d0300 · Lixiaokeng <[email protected]> · 2021-12-20 19:39:06 +08:00

|- iscsi_if_destroy_conn            |-dev_attr_show
 |-iscsi_conn_teardown
  |-spin_lock_bh                     |-iscsi_sw_tcp_conn_get_param

  |-kfree(conn->persistent_address)   |-iscsi_conn_get_param
  |-kfree(conn->local_ipaddr)
                                       ==>|-read persistent_address
                                       ==>|-read local_ipaddr
  |-spin_unlock_bh

When iscsi_conn_teardown() and iscsi_conn_get_param() happen in parallel, a
UAF may be triggered.

Link: https://lore.kernel.org/r/[email protected]
Reported-by: Lu Tixiong <[email protected]>
Reviewed-by: Mike Christie <[email protected]>
Reviewed-by: Lee Duncan <[email protected]>
Signed-off-by: Lixiaokeng <[email protected]>
Signed-off-by: Linfeilong <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
Commit
1b8d0300a3e9f216ae4901bab886db7299899ec6
Parents
9020be11

Changes

1 files changed · +4 −2

FileStatusAddDelContent
drivers/scsi/libiscsi.cmodified+4−2View file

drivers/scsi/libiscsi.c

View file
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 284b939..059dae8 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -3100,6 +3100,8 @@ 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;
del_timer_sync(&conn->transport_timer);
@@ -3121,8 +3123,6 @@ 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,
@@ -3134,6 +3134,8 @@ 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);