From: Jacob Pan <jacob.jun.pan@linux.intel.com>
To: LKML <linux-kernel@vger.kernel.org>,
iommu@lists.linux-foundation.org,
"Lu Baolu" <baolu.lu@linux.intel.com>,
Joerg Roedel <joro@8bytes.org>,
David Woodhouse <dwmw2@infradead.org>
Cc: Raj Ashok <ashok.raj@intel.com>
Subject: [PATCH 2/3] iommu/vt-d: Fix mm reference leak
Date: Thu, 19 Mar 2020 21:32:30 -0700 [thread overview]
Message-ID: <1584678751-43169-3-git-send-email-jacob.jun.pan@linux.intel.com> (raw)
In-Reply-To: <1584678751-43169-1-git-send-email-jacob.jun.pan@linux.intel.com>
Move canonical address check before mmget_not_zero() to avoid mm
reference leak.
Fixes: 9d8c3af31607 ("iommu/vt-d: IOMMU Page Request needs to check if
address is canonical.")
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
---
drivers/iommu/intel-svm.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index 1483f1845762..56253c59ca10 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -861,14 +861,15 @@ static irqreturn_t prq_event_thread(int irq, void *d)
* any faults on kernel addresses. */
if (!svm->mm)
goto bad_req;
- /* If the mm is already defunct, don't handle faults. */
- if (!mmget_not_zero(svm->mm))
- goto bad_req;
/* If address is not canonical, return invalid response */
if (!is_canonical_address(address))
goto bad_req;
+ /* If the mm is already defunct, don't handle faults. */
+ if (!mmget_not_zero(svm->mm))
+ goto bad_req;
+
down_read(&svm->mm->mmap_sem);
vma = find_extend_vma(svm->mm, address);
if (!vma || address < vma->vm_start)
--
2.7.4
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next prev parent reply other threads:[~2020-03-20 4:26 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-20 4:32 [PATCH 0/3] Misc bug fixes for VT-d SVM Jacob Pan
2020-03-20 4:32 ` [PATCH 1/3] iommu/vt-d: Remove redundant IOTLB flush Jacob Pan
2020-03-20 13:45 ` Lu Baolu
2020-03-20 16:20 ` Jacob Pan
2020-03-21 1:32 ` Lu Baolu
2020-03-24 15:31 ` Jacob Pan
2020-03-25 0:48 ` Lu Baolu
2020-03-20 4:32 ` Jacob Pan [this message]
2020-03-20 13:49 ` [PATCH 2/3] iommu/vt-d: Fix mm reference leak Lu Baolu
2020-03-20 4:32 ` [PATCH 3/3] iommu/vt-d: Add build dependency on IOASID Jacob Pan
2020-03-20 13:57 ` Lu Baolu
2020-03-27 10:04 ` [PATCH 0/3] Misc bug fixes for VT-d SVM Joerg Roedel
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