[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <A2975661238FB949B60364EF0F2C257439D5DF53@SHSMSX104.ccr.corp.intel.com>
Date: Mon, 5 Nov 2018 05:21:35 +0000
From: "Liu, Yi L" <yi.l.liu@...el.com>
To: Lu Baolu <baolu.lu@...ux.intel.com>,
Joerg Roedel <joro@...tes.org>,
David Woodhouse <dwmw2@...radead.org>
CC: "Raj, Ashok" <ashok.raj@...el.com>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"iommu@...ts.linux-foundation.org" <iommu@...ts.linux-foundation.org>
Subject: RE: [PATCH 1/1] iommu/vtd: Fix NULL pointer dereference in
prq_event_thread()
Hi Baolu,
> From: iommu-bounces@...ts.linux-foundation.org [mailto:iommu-
> bounces@...ts.linux-foundation.org] On Behalf Of Lu Baolu
> Sent: Monday, November 5, 2018 10:19 AM
> To: Joerg Roedel <joro@...tes.org>; David Woodhouse <dwmw2@...radead.org>
> Cc: Raj, Ashok <ashok.raj@...el.com>; linux-kernel@...r.kernel.org;
> iommu@...ts.linux-foundation.org
> Subject: [PATCH 1/1] iommu/vtd: Fix NULL pointer dereference in prq_event_thread()
>
> When handling page request without pasid event, go to "no_pasid"
> branch instead of "bad_req". Otherwise, a NULL pointer deference will happen there.
>
> Cc: Ashok Raj <ashok.raj@...el.com>
> Cc: Jacob Pan <jacob.jun.pan@...ux.intel.com>
> Cc: Sohil Mehta <sohil.mehta@...el.com>
> Signed-off-by: Lu Baolu <baolu.lu@...ux.intel.com>
> ---
> drivers/iommu/intel-svm.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index
> db301efe126d..887150907526 100644
> --- a/drivers/iommu/intel-svm.c
> +++ b/drivers/iommu/intel-svm.c
> @@ -595,7 +595,7 @@ static irqreturn_t prq_event_thread(int irq, void *d)
> pr_err("%s: Page request without PASID: %08llx %08llx\n",
> iommu->name, ((unsigned long long *)req)[0],
> ((unsigned long long *)req)[1]);
> - goto bad_req;
> + goto no_pasid;
> }
>
> if (!svm || svm->pasid != req->pasid) {
> --
I'm afraid it is still necessary to goto "bad_req". The following code behind
"bad_req" will trigger fault_cb registered by in-kernel drivers. It is reasonable
that PRQ without PASID can be handled by such callbacks. So I would suggest
to keep the existing logic.
if (sdev && sdev->ops && sdev->ops->fault_cb) {
int rwxp = (req->rd_req << 3) | (req->wr_req << 2) |
(req->exe_req << 1) | (req->priv_req);
sdev->ops->fault_cb(sdev->dev, req->pasid, req->addr, req->private, rwxp, result);
}
Thanks,
Yi Liu
Powered by blists - more mailing lists