From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: "Reshetova, Elena" To: Chris Leech CC: "gregkh@linuxfoundation.org" , "linux-kernel@vger.kernel.org" , "xen-devel@lists.xenproject.org" , "netdev@vger.kernel.org" , "linux1394-devel@lists.sourceforge.net" , "linux-bcache@vger.kernel.org" , "linux-raid@vger.kernel.org" , "linux-media@vger.kernel.org" , "devel@linuxdriverproject.org" , "linux-pci@vger.kernel.org" , "linux-s390@vger.kernel.org" , "fcoe-devel@open-fcoe.org" , "linux-scsi@vger.kernel.org" , "open-iscsi@googlegroups.com" , "devel@driverdev.osuosl.org" , "target-devel@vger.kernel.org" , "linux-serial@vger.kernel.org" , "linux-usb@vger.kernel.org" , "peterz@infradead.org" , Hans Liljestrand , Kees Cook , David Windsor Subject: RE: [PATCH 22/29] drivers, scsi: convert iscsi_task.refcount from atomic_t to refcount_t Date: Thu, 9 Mar 2017 07:18:29 +0000 Message-ID: <2236FBA76BA1254E88B949DDB74E612B41C569DC@IRSMSX102.ger.corp.intel.com> References: <1488810076-3754-1-git-send-email-elena.reshetova@intel.com> <1488810076-3754-23-git-send-email-elena.reshetova@intel.com> <20170308184740.4gueok5csdkt7u62@straylight.hirudinean.org> In-Reply-To: <20170308184740.4gueok5csdkt7u62@straylight.hirudinean.org> Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: > 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 > > Signed-off-by: Hans Liljestrand > > Signed-off-by: Kees Cook > > Signed-off-by: David Windsor > > This looks OK to me. > > Acked-by: Chris Leech 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 > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -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 > >