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| author | Jacob Pan <jacob.jun.pan@linux.intel.com> | 2020-03-20 05:32:30 +0100 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2020-03-27 11:03:04 +0100 |
| commit | 902baf61adf6b187f0a6b789e70d788ea71ff5bc (patch) | |
| tree | 91a72f88bcc5e8498465c609098468ab3880e457 /drivers/iommu | |
| parent | Linux 5.6-rc3 (diff) | |
| download | linux-902baf61adf6b187f0a6b789e70d788ea71ff5bc.tar.xz linux-902baf61adf6b187f0a6b789e70d788ea71ff5bc.zip | |
iommu/vt-d: Fix mm reference leak
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>
Diffstat (limited to 'drivers/iommu')
| -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) |