scsi: libiscsi: qedi: convert iscsi_task.refcount from atomic_t to refcount_t

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>
Acked-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Elena Reshetova 2017-03-09 13:46:58 +02:00 committed by Martin K. Petersen
parent 22c70d1a9c
commit 6dc618cdd6
3 changed files with 7 additions and 6 deletions

View File

@ -517,13 +517,13 @@ 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);
@ -745,7 +745,7 @@ __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);
@ -1617,7 +1617,7 @@ 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;

View File

@ -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;
}

View File

@ -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 */
};