diff mbox

[22/29] drivers, scsi: convert iscsi_task.refcount from atomic_t to refcount_t

Message ID 1488810076-3754-23-git-send-email-elena.reshetova@intel.com (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Reshetova, Elena March 6, 2017, 2:21 p.m. UTC
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
---
 drivers/scsi/libiscsi.c        | 8 ++++----
 drivers/scsi/qedi/qedi_iscsi.c | 2 +-
 include/scsi/libiscsi.h        | 3 ++-
 3 files changed, 7 insertions(+), 6 deletions(-)

Comments

Chris Leech March 8, 2017, 6:47 p.m. UTC | #1
On Mon, Mar 06, 2017 at 04:21:09PM +0200, Elena Reshetova wrote:
> refcount_t type and corresponding API should be
> used instead of atomic_t when the variable is used as
> a reference counter. This allows to avoid accidental
> refcounter overflows that might lead to use-after-free
> situations.
> 
> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
> Signed-off-by: Kees Cook <keescook@chromium.org>
> Signed-off-by: David Windsor <dwindsor@gmail.com>

This looks OK to me.

Acked-by: Chris Leech <cleech@redhat.com>

> ---
>  drivers/scsi/libiscsi.c        | 8 ++++----
>  drivers/scsi/qedi/qedi_iscsi.c | 2 +-
>  include/scsi/libiscsi.h        | 3 ++-
>  3 files changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
> index 834d121..7eb1d2c 100644
> --- a/drivers/scsi/libiscsi.c
> +++ b/drivers/scsi/libiscsi.c
> @@ -516,13 +516,13 @@ static void iscsi_free_task(struct iscsi_task *task)
>  
>  void __iscsi_get_task(struct iscsi_task *task)
>  {
> -	atomic_inc(&task->refcount);
> +	refcount_inc(&task->refcount);
>  }
>  EXPORT_SYMBOL_GPL(__iscsi_get_task);
>  
>  void __iscsi_put_task(struct iscsi_task *task)
>  {
> -	if (atomic_dec_and_test(&task->refcount))
> +	if (refcount_dec_and_test(&task->refcount))
>  		iscsi_free_task(task);
>  }
>  EXPORT_SYMBOL_GPL(__iscsi_put_task);
> @@ -744,7 +744,7 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
>  	 * released by the lld when it has transmitted the task for
>  	 * pdus we do not expect a response for.
>  	 */
> -	atomic_set(&task->refcount, 1);
> +	refcount_set(&task->refcount, 1);
>  	task->conn = conn;
>  	task->sc = NULL;
>  	INIT_LIST_HEAD(&task->running);
> @@ -1616,7 +1616,7 @@ static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
>  	sc->SCp.phase = conn->session->age;
>  	sc->SCp.ptr = (char *) task;
>  
> -	atomic_set(&task->refcount, 1);
> +	refcount_set(&task->refcount, 1);
>  	task->state = ISCSI_TASK_PENDING;
>  	task->conn = conn;
>  	task->sc = sc;
> diff --git a/drivers/scsi/qedi/qedi_iscsi.c b/drivers/scsi/qedi/qedi_iscsi.c
> index b9f79d3..3895bd5 100644
> --- a/drivers/scsi/qedi/qedi_iscsi.c
> +++ b/drivers/scsi/qedi/qedi_iscsi.c
> @@ -1372,7 +1372,7 @@ static void qedi_cleanup_task(struct iscsi_task *task)
>  {
>  	if (!task->sc || task->state == ISCSI_TASK_PENDING) {
>  		QEDI_INFO(NULL, QEDI_LOG_IO, "Returning ref_cnt=%d\n",
> -			  atomic_read(&task->refcount));
> +			  refcount_read(&task->refcount));
>  		return;
>  	}
>  
> diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
> index b0e275d..24d74b5 100644
> --- a/include/scsi/libiscsi.h
> +++ b/include/scsi/libiscsi.h
> @@ -29,6 +29,7 @@
>  #include <linux/timer.h>
>  #include <linux/workqueue.h>
>  #include <linux/kfifo.h>
> +#include <linux/refcount.h>
>  #include <scsi/iscsi_proto.h>
>  #include <scsi/iscsi_if.h>
>  #include <scsi/scsi_transport_iscsi.h>
> @@ -139,7 +140,7 @@ struct iscsi_task {
>  
>  	/* state set/tested under session->lock */
>  	int			state;
> -	atomic_t		refcount;
> +	refcount_t		refcount;
>  	struct list_head	running;	/* running cmd list */
>  	void			*dd_data;	/* driver/transport data */
>  };
> -- 
> 2.7.4
>
Reshetova, Elena March 9, 2017, 7:18 a.m. UTC | #2
> On Mon, Mar 06, 2017 at 04:21:09PM +0200, Elena Reshetova wrote:
> > refcount_t type and corresponding API should be
> > used instead of atomic_t when the variable is used as
> > a reference counter. This allows to avoid accidental
> > refcounter overflows that might lead to use-after-free
> > situations.
> >
> > Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> > Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
> > Signed-off-by: Kees Cook <keescook@chromium.org>
> > Signed-off-by: David Windsor <dwindsor@gmail.com>
> 
> This looks OK to me.
> 
> Acked-by: Chris Leech <cleech@redhat.com>

Thank you for review! Do you have a tree that can take this change? 

Best Regards,
Elena.

> 
> > ---
> >  drivers/scsi/libiscsi.c        | 8 ++++----
> >  drivers/scsi/qedi/qedi_iscsi.c | 2 +-
> >  include/scsi/libiscsi.h        | 3 ++-
> >  3 files changed, 7 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
> > index 834d121..7eb1d2c 100644
> > --- a/drivers/scsi/libiscsi.c
> > +++ b/drivers/scsi/libiscsi.c
> > @@ -516,13 +516,13 @@ static void iscsi_free_task(struct iscsi_task *task)
> >
> >  void __iscsi_get_task(struct iscsi_task *task)
> >  {
> > -	atomic_inc(&task->refcount);
> > +	refcount_inc(&task->refcount);
> >  }
> >  EXPORT_SYMBOL_GPL(__iscsi_get_task);
> >
> >  void __iscsi_put_task(struct iscsi_task *task)
> >  {
> > -	if (atomic_dec_and_test(&task->refcount))
> > +	if (refcount_dec_and_test(&task->refcount))
> >  		iscsi_free_task(task);
> >  }
> >  EXPORT_SYMBOL_GPL(__iscsi_put_task);
> > @@ -744,7 +744,7 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct
> iscsi_hdr *hdr,
> >  	 * released by the lld when it has transmitted the task for
> >  	 * pdus we do not expect a response for.
> >  	 */
> > -	atomic_set(&task->refcount, 1);
> > +	refcount_set(&task->refcount, 1);
> >  	task->conn = conn;
> >  	task->sc = NULL;
> >  	INIT_LIST_HEAD(&task->running);
> > @@ -1616,7 +1616,7 @@ static inline struct iscsi_task *iscsi_alloc_task(struct
> iscsi_conn *conn,
> >  	sc->SCp.phase = conn->session->age;
> >  	sc->SCp.ptr = (char *) task;
> >
> > -	atomic_set(&task->refcount, 1);
> > +	refcount_set(&task->refcount, 1);
> >  	task->state = ISCSI_TASK_PENDING;
> >  	task->conn = conn;
> >  	task->sc = sc;
> > diff --git a/drivers/scsi/qedi/qedi_iscsi.c b/drivers/scsi/qedi/qedi_iscsi.c
> > index b9f79d3..3895bd5 100644
> > --- a/drivers/scsi/qedi/qedi_iscsi.c
> > +++ b/drivers/scsi/qedi/qedi_iscsi.c
> > @@ -1372,7 +1372,7 @@ static void qedi_cleanup_task(struct iscsi_task *task)
> >  {
> >  	if (!task->sc || task->state == ISCSI_TASK_PENDING) {
> >  		QEDI_INFO(NULL, QEDI_LOG_IO, "Returning
> ref_cnt=%d\n",
> > -			  atomic_read(&task->refcount));
> > +			  refcount_read(&task->refcount));
> >  		return;
> >  	}
> >
> > diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
> > index b0e275d..24d74b5 100644
> > --- a/include/scsi/libiscsi.h
> > +++ b/include/scsi/libiscsi.h
> > @@ -29,6 +29,7 @@
> >  #include <linux/timer.h>
> >  #include <linux/workqueue.h>
> >  #include <linux/kfifo.h>
> > +#include <linux/refcount.h>
> >  #include <scsi/iscsi_proto.h>
> >  #include <scsi/iscsi_if.h>
> >  #include <scsi/scsi_transport_iscsi.h>
> > @@ -139,7 +140,7 @@ struct iscsi_task {
> >
> >  	/* state set/tested under session->lock */
> >  	int			state;
> > -	atomic_t		refcount;
> > +	refcount_t		refcount;
> >  	struct list_head	running;	/* running cmd list */
> >  	void			*dd_data;	/*
> driver/transport data */
> >  };
> > --
> > 2.7.4
> >
Johannes Thumshirn March 9, 2017, 8:43 a.m. UTC | #3
On 03/09/2017 08:18 AM, Reshetova, Elena wrote:
>> On Mon, Mar 06, 2017 at 04:21:09PM +0200, Elena Reshetova wrote:
>>> refcount_t type and corresponding API should be
>>> used instead of atomic_t when the variable is used as
>>> a reference counter. This allows to avoid accidental
>>> refcounter overflows that might lead to use-after-free
>>> situations.
>>>
>>> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
>>> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
>>> Signed-off-by: Kees Cook <keescook@chromium.org>
>>> Signed-off-by: David Windsor <dwindsor@gmail.com>
>>
>> This looks OK to me.
>>
>> Acked-by: Chris Leech <cleech@redhat.com>
> 
> Thank you for review! Do you have a tree that can take this change? 

Hi Elena,

iscsi like fcoe should go via the SCSI tree.

Byte,
	Johannes
Reshetova, Elena March 9, 2017, 9:26 a.m. UTC | #4
> On 03/09/2017 08:18 AM, Reshetova, Elena wrote:
> >> On Mon, Mar 06, 2017 at 04:21:09PM +0200, Elena Reshetova wrote:
> >>> refcount_t type and corresponding API should be
> >>> used instead of atomic_t when the variable is used as
> >>> a reference counter. This allows to avoid accidental
> >>> refcounter overflows that might lead to use-after-free
> >>> situations.
> >>>
> >>> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> >>> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
> >>> Signed-off-by: Kees Cook <keescook@chromium.org>
> >>> Signed-off-by: David Windsor <dwindsor@gmail.com>
> >>
> >> This looks OK to me.
> >>
> >> Acked-by: Chris Leech <cleech@redhat.com>
> >
> > Thank you for review! Do you have a tree that can take this change?
> 
> Hi Elena,
> 
> iscsi like fcoe should go via the SCSI tree.

Thanks Johannes! Should I resend with "Acked-by" added in order for it to be picked up? 

Best Regards,
Elena.


> 
> Byte,
> 	Johannes
> 
> --
> Johannes Thumshirn                                          Storage
> jthumshirn@suse.de                                +49 911 74053 689
> SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
> GF: Felix Imendörffer, Jane Smithard, Graham Norton
> HRB 21284 (AG Nürnberg)
> Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850
Johannes Thumshirn March 9, 2017, 9:32 a.m. UTC | #5
On 03/09/2017 10:26 AM, Reshetova, Elena wrote:
> 
>> On 03/09/2017 08:18 AM, Reshetova, Elena wrote:
>>>> On Mon, Mar 06, 2017 at 04:21:09PM +0200, Elena Reshetova wrote:
>>>>> refcount_t type and corresponding API should be
>>>>> used instead of atomic_t when the variable is used as
>>>>> a reference counter. This allows to avoid accidental
>>>>> refcounter overflows that might lead to use-after-free
>>>>> situations.
>>>>>
>>>>> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
>>>>> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
>>>>> Signed-off-by: Kees Cook <keescook@chromium.org>
>>>>> Signed-off-by: David Windsor <dwindsor@gmail.com>
>>>>
>>>> This looks OK to me.
>>>>
>>>> Acked-by: Chris Leech <cleech@redhat.com>
>>>
>>> Thank you for review! Do you have a tree that can take this change?
>>
>> Hi Elena,
>>
>> iscsi like fcoe should go via the SCSI tree.
> 
> Thanks Johannes! Should I resend with "Acked-by" added in order for it to be picked up? 

Yes I think this would be a good way to go.

Byte,
	Johannes
diff mbox

Patch

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 834d121..7eb1d2c 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -516,13 +516,13 @@  static void iscsi_free_task(struct iscsi_task *task)
 
 void __iscsi_get_task(struct iscsi_task *task)
 {
-	atomic_inc(&task->refcount);
+	refcount_inc(&task->refcount);
 }
 EXPORT_SYMBOL_GPL(__iscsi_get_task);
 
 void __iscsi_put_task(struct iscsi_task *task)
 {
-	if (atomic_dec_and_test(&task->refcount))
+	if (refcount_dec_and_test(&task->refcount))
 		iscsi_free_task(task);
 }
 EXPORT_SYMBOL_GPL(__iscsi_put_task);
@@ -744,7 +744,7 @@  __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 	 * released by the lld when it has transmitted the task for
 	 * pdus we do not expect a response for.
 	 */
-	atomic_set(&task->refcount, 1);
+	refcount_set(&task->refcount, 1);
 	task->conn = conn;
 	task->sc = NULL;
 	INIT_LIST_HEAD(&task->running);
@@ -1616,7 +1616,7 @@  static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
 	sc->SCp.phase = conn->session->age;
 	sc->SCp.ptr = (char *) task;
 
-	atomic_set(&task->refcount, 1);
+	refcount_set(&task->refcount, 1);
 	task->state = ISCSI_TASK_PENDING;
 	task->conn = conn;
 	task->sc = sc;
diff --git a/drivers/scsi/qedi/qedi_iscsi.c b/drivers/scsi/qedi/qedi_iscsi.c
index b9f79d3..3895bd5 100644
--- a/drivers/scsi/qedi/qedi_iscsi.c
+++ b/drivers/scsi/qedi/qedi_iscsi.c
@@ -1372,7 +1372,7 @@  static void qedi_cleanup_task(struct iscsi_task *task)
 {
 	if (!task->sc || task->state == ISCSI_TASK_PENDING) {
 		QEDI_INFO(NULL, QEDI_LOG_IO, "Returning ref_cnt=%d\n",
-			  atomic_read(&task->refcount));
+			  refcount_read(&task->refcount));
 		return;
 	}
 
diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index b0e275d..24d74b5 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -29,6 +29,7 @@ 
 #include <linux/timer.h>
 #include <linux/workqueue.h>
 #include <linux/kfifo.h>
+#include <linux/refcount.h>
 #include <scsi/iscsi_proto.h>
 #include <scsi/iscsi_if.h>
 #include <scsi/scsi_transport_iscsi.h>
@@ -139,7 +140,7 @@  struct iscsi_task {
 
 	/* state set/tested under session->lock */
 	int			state;
-	atomic_t		refcount;
+	refcount_t		refcount;
 	struct list_head	running;	/* running cmd list */
 	void			*dd_data;	/* driver/transport data */
 };