2020-11-20 07:47:15

by Qinglang Miao

Subject: [PATCH] scsi: iscsi: fix inappropriate use of put_device

kfree(conn) is called inside put_device(&conn->dev) so that
another one would cause use-after-free. Besides, device_unregister
should be used here rather than put_device.

Fixes: f3c893e3dbb5 ("scsi: iscsi: Fail session and connection on transport registration failure")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: Qinglang Miao <[email protected]>
---
drivers/scsi/scsi_transport_iscsi.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 2eb3e4f93..2e68c0a87 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -2313,7 +2313,9 @@ iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
return conn;

release_conn_ref:
- put_device(&conn->dev);
+ device_unregister(&conn->dev);
+ put_device(&session->dev);
+ return NULL;
release_parent_ref:
put_device(&session->dev);
free_conn:
--
2.23.0

2020-12-02 19:38:20

by Mike Christie

Subject: Re: [PATCH] scsi: iscsi: fix inappropriate use of put_device

On 11/20/20 1:48 AM, Qinglang Miao wrote:
> kfree(conn) is called inside put_device(&conn->dev) so that
> another one would cause use-after-free. Besides, device_unregister
> should be used here rather than put_device.
>
> Fixes: f3c893e3dbb5 ("scsi: iscsi: Fail session and connection on transport registration failure")
> Reported-by: Hulk Robot <[email protected]>
> Signed-off-by: Qinglang Miao <[email protected]>
> ---
> drivers/scsi/scsi_transport_iscsi.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
> index 2eb3e4f93..2e68c0a87 100644
> --- a/drivers/scsi/scsi_transport_iscsi.c
> +++ b/drivers/scsi/scsi_transport_iscsi.c
> @@ -2313,7 +2313,9 @@ iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
> return conn;
>
> release_conn_ref:
> - put_device(&conn->dev);
> + device_unregister(&conn->dev);
> + put_device(&session->dev);
> + return NULL;
> release_parent_ref:
> put_device(&session->dev);
> free_conn:
>

Reviewed-by: Mike Christie <[email protected]>

2020-12-09 17:28:54

by Martin K. Petersen

Subject: Re: [PATCH] scsi: iscsi: fix inappropriate use of put_device

On Fri, 20 Nov 2020 15:48:52 +0800, Qinglang Miao wrote:

> kfree(conn) is called inside put_device(&conn->dev) so that
> another one would cause use-after-free. Besides, device_unregister
> should be used here rather than put_device.

Applied to 5.11/scsi-queue, thanks!

[1/1] scsi: iscsi: fix inappropriate use of put_device
https://git.kernel.org/mkp/scsi/c/6dc1c7ab6f04

--
Martin K. Petersen Oracle Linux Engineering