Message ID | 1600286999-22059-1-git-send-email-brking@linux.vnet.ibm.com |
---|---|
State | New |
Headers | show |
Series | ibmvfc: Protect vhost->task_set increment by the host lock | expand |
Brian, > In the discovery thread, ibmvfc does a vhost->task_set++ without any > lock held. This could result in two targets getting the same cancel > key, which could have strange effects in error recovery. The actual > probability of this occurring should be extremely small, since this > should all be done in a single threaded loop from the discovery > thread, but let's fix it up anyway to be safe. Applied to 5.10/scsi-staging, thanks! -- Martin K. Petersen Oracle Linux Engineering
On Wed, 16 Sep 2020 15:09:59 -0500, Brian King wrote: > In the discovery thread, ibmvfc does a vhost->task_set++ without > any lock held. This could result in two targets getting the same > cancel key, which could have strange effects in error recovery. > The actual probability of this occurring should be extremely > small, since this should all be done in a single threaded loop > from the discovery thread, but let's fix it up anyway to be safe. Applied to 5.10/scsi-queue, thanks! [1/1] scsi: ibmvfc: Protect vhost->task_set increment by the host lock https://git.kernel.org/mkp/scsi/c/2584e5aef87a
diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c index 322bb30..b393587 100644 --- a/drivers/scsi/ibmvscsi/ibmvfc.c +++ b/drivers/scsi/ibmvscsi/ibmvfc.c @@ -4169,11 +4169,11 @@ static int ibmvfc_alloc_target(struct ibmvfc_host *vhost,struct ibmvfc_discover_ tgt->wwpn = wwpn; tgt->vhost = vhost; tgt->need_login = 1; - tgt->cancel_key = vhost->task_set++; timer_setup(&tgt->timer, ibmvfc_adisc_timeout, 0); kref_init(&tgt->kref); ibmvfc_init_tgt(tgt, ibmvfc_tgt_implicit_logout); spin_lock_irqsave(vhost->host->host_lock, flags); + tgt->cancel_key = vhost->task_set++; list_add_tail(&tgt->queue, &vhost->targets); unlock_out:
In the discovery thread, ibmvfc does a vhost->task_set++ without any lock held. This could result in two targets getting the same cancel key, which could have strange effects in error recovery. The actual probability of this occurring should be extremely small, since this should all be done in a single threaded loop from the discovery thread, but let's fix it up anyway to be safe. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> --- drivers/scsi/ibmvscsi/ibmvfc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)