diff options
| author | Jacob Pan <jacob.jun.pan@linux.intel.com> | 2020-03-20 07:32:30 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-04-23 11:38:18 +0300 |
| commit | 2cf6e0ec9b7f970904e97a6d886862e974e3188b (patch) | |
| tree | c5d5d65a941b988442b5c4dc8a013a168c74971c | |
| parent | 06cf124d3dbbfb71d01f87a2d9401af9a457c266 (diff) | |
| download | linux-2cf6e0ec9b7f970904e97a6d886862e974e3188b.tar.xz | |
iommu/vt-d: Fix mm reference leak
[ Upstream commit 902baf61adf6b187f0a6b789e70d788ea71ff5bc ]
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>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/iommu/intel-svm.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index d7f2a5358900..fc7d78876e02 100644 --- a/drivers/iommu/intel-svm.c +++ b/drivers/iommu/intel-svm.c @@ -611,14 +611,15 @@ 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) |