[PATCH 0/1][Disco][Cosmic][Bionic] Backport race condition fix

classic Classic list List threaded Threaded
6 messages Options
Reply | Threaded
Open this post in threaded view
|

[PATCH 0/1][Disco][Cosmic][Bionic] Backport race condition fix

Ike Panhc
Please backport patch b90cd6f2b9 from upstream for bionic,
cosmic and disco. This patch can be cleanly cherry-picked.

Buglink: http://bugs.launchpad.net/bugs/1808912

Jason Yan (1):
  scsi: libsas: fix a race condition when smp task timeout

 drivers/scsi/libsas/sas_expander.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

--
2.17.1


--
kernel-team mailing list
[hidden email]
https://lists.ubuntu.com/mailman/listinfo/kernel-team
Reply | Threaded
Open this post in threaded view
|

[PATCH 1/1] scsi: libsas: fix a race condition when smp task timeout

Ike Panhc
From: Jason Yan <[hidden email]>

Buglink: http://bugs.launchpad.net/bugs/1808912

When the lldd is processing the complete sas task in interrupt and set the
task stat as SAS_TASK_STATE_DONE, the smp timeout timer is able to be
triggered at the same time. And smp_task_timedout() will complete the task
wheter the SAS_TASK_STATE_DONE is set or not. Then the sas task may freed
before lldd end the interrupt process. Thus a use-after-free will happen.

Fix this by calling the complete() only when SAS_TASK_STATE_DONE is not
set. And remove the check of the return value of the del_timer(). Once the
LLDD sets DONE, it must call task->done(), which will call
smp_task_done()->complete() and the task will be completed and freed
correctly.

Reported-by: chenxiang <[hidden email]>
Signed-off-by: Jason Yan <[hidden email]>
CC: John Garry <[hidden email]>
CC: Johannes Thumshirn <[hidden email]>
CC: Ewan Milne <[hidden email]>
CC: Christoph Hellwig <[hidden email]>
CC: Tomas Henzl <[hidden email]>
CC: Dan Williams <[hidden email]>
CC: Hannes Reinecke <[hidden email]>
Reviewed-by: Hannes Reinecke <[hidden email]>
Reviewed-by: John Garry <[hidden email]>
Reviewed-by: Johannes Thumshirn <[hidden email]>
Signed-off-by: Martin K. Petersen <[hidden email]>
(cherry picked from commit b90cd6f2b905905fb42671009dc0e27c310a16ae)
Signed-off-by: Ike Panhc <[hidden email]>
---
 drivers/scsi/libsas/sas_expander.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c
index 6a4f8198b78e..0ebed2a86b97 100644
--- a/drivers/scsi/libsas/sas_expander.c
+++ b/drivers/scsi/libsas/sas_expander.c
@@ -48,17 +48,16 @@ static void smp_task_timedout(struct timer_list *t)
  unsigned long flags;
 
  spin_lock_irqsave(&task->task_state_lock, flags);
- if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
+ if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
  task->task_state_flags |= SAS_TASK_STATE_ABORTED;
+ complete(&task->slow_task->completion);
+ }
  spin_unlock_irqrestore(&task->task_state_lock, flags);
-
- complete(&task->slow_task->completion);
 }
 
 static void smp_task_done(struct sas_task *task)
 {
- if (!del_timer(&task->slow_task->timer))
- return;
+ del_timer(&task->slow_task->timer);
  complete(&task->slow_task->completion);
 }
 
--
2.17.1


--
kernel-team mailing list
[hidden email]
https://lists.ubuntu.com/mailman/listinfo/kernel-team
Reply | Threaded
Open this post in threaded view
|

ACK: [PATCH 0/1][Disco][Cosmic][Bionic] Backport race condition fix

Khaled Elmously
In reply to this post by Ike Panhc
On 2018-12-18 14:08:49 , Ike Panhc wrote:

> Please backport patch b90cd6f2b9 from upstream for bionic,
> cosmic and disco. This patch can be cleanly cherry-picked.
>
> Buglink: http://bugs.launchpad.net/bugs/1808912
>
> Jason Yan (1):
>   scsi: libsas: fix a race condition when smp task timeout
>
>  drivers/scsi/libsas/sas_expander.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
>

Acked-by: Khalid Elmously <[hidden email]>
 

--
kernel-team mailing list
[hidden email]
https://lists.ubuntu.com/mailman/listinfo/kernel-team
Reply | Threaded
Open this post in threaded view
|

ACK: [PATCH 1/1] scsi: libsas: fix a race condition when smp task timeout

Kleber Souza
In reply to this post by Ike Panhc
On 12/18/18 7:09 AM, Ike Panhc wrote:

> From: Jason Yan <[hidden email]>
>
> Buglink: http://bugs.launchpad.net/bugs/1808912
>
> When the lldd is processing the complete sas task in interrupt and set the
> task stat as SAS_TASK_STATE_DONE, the smp timeout timer is able to be
> triggered at the same time. And smp_task_timedout() will complete the task
> wheter the SAS_TASK_STATE_DONE is set or not. Then the sas task may freed
> before lldd end the interrupt process. Thus a use-after-free will happen.
>
> Fix this by calling the complete() only when SAS_TASK_STATE_DONE is not
> set. And remove the check of the return value of the del_timer(). Once the
> LLDD sets DONE, it must call task->done(), which will call
> smp_task_done()->complete() and the task will be completed and freed
> correctly.
>
> Reported-by: chenxiang <[hidden email]>
> Signed-off-by: Jason Yan <[hidden email]>
> CC: John Garry <[hidden email]>
> CC: Johannes Thumshirn <[hidden email]>
> CC: Ewan Milne <[hidden email]>
> CC: Christoph Hellwig <[hidden email]>
> CC: Tomas Henzl <[hidden email]>
> CC: Dan Williams <[hidden email]>
> CC: Hannes Reinecke <[hidden email]>
> Reviewed-by: Hannes Reinecke <[hidden email]>
> Reviewed-by: John Garry <[hidden email]>
> Reviewed-by: Johannes Thumshirn <[hidden email]>
> Signed-off-by: Martin K. Petersen <[hidden email]>
> (cherry picked from commit b90cd6f2b905905fb42671009dc0e27c310a16ae)
> Signed-off-by: Ike Panhc <[hidden email]>
Acked-by: Kleber Sacilotto de Souza <[hidden email]>

> ---
>  drivers/scsi/libsas/sas_expander.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c
> index 6a4f8198b78e..0ebed2a86b97 100644
> --- a/drivers/scsi/libsas/sas_expander.c
> +++ b/drivers/scsi/libsas/sas_expander.c
> @@ -48,17 +48,16 @@ static void smp_task_timedout(struct timer_list *t)
>   unsigned long flags;
>  
>   spin_lock_irqsave(&task->task_state_lock, flags);
> - if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
> + if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
>   task->task_state_flags |= SAS_TASK_STATE_ABORTED;
> + complete(&task->slow_task->completion);
> + }
>   spin_unlock_irqrestore(&task->task_state_lock, flags);
> -
> - complete(&task->slow_task->completion);
>  }
>  
>  static void smp_task_done(struct sas_task *task)
>  {
> - if (!del_timer(&task->slow_task->timer))
> - return;
> + del_timer(&task->slow_task->timer);
>   complete(&task->slow_task->completion);
>  }
>  



--
kernel-team mailing list
[hidden email]
https://lists.ubuntu.com/mailman/listinfo/kernel-team
Reply | Threaded
Open this post in threaded view
|

APPLIED[D]: [PATCH 0/1][Disco][Cosmic][Bionic] Backport race condition fix

Seth Forshee
In reply to this post by Ike Panhc
On Tue, Dec 18, 2018 at 02:08:49PM +0800, Ike Panhc wrote:
> Please backport patch b90cd6f2b9 from upstream for bionic,
> cosmic and disco. This patch can be cleanly cherry-picked.
>
> Buglink: http://bugs.launchpad.net/bugs/1808912

Applied to disco/master-next, thanks!

--
kernel-team mailing list
[hidden email]
https://lists.ubuntu.com/mailman/listinfo/kernel-team
Reply | Threaded
Open this post in threaded view
|

APPLIED[B/C]: [PATCH 0/1][Disco][Cosmic][Bionic] Backport race condition fix

Kleber Souza
In reply to this post by Ike Panhc
On 12/18/18 7:08 AM, Ike Panhc wrote:

> Please backport patch b90cd6f2b9 from upstream for bionic,
> cosmic and disco. This patch can be cleanly cherry-picked.
>
> Buglink: http://bugs.launchpad.net/bugs/1808912
>
> Jason Yan (1):
>   scsi: libsas: fix a race condition when smp task timeout
>
>  drivers/scsi/libsas/sas_expander.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
>
Applied to bionic/master-next and cosmic/master-next branches.

Thanks,
Kleber


--
kernel-team mailing list
[hidden email]
https://lists.ubuntu.com/mailman/listinfo/kernel-team