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| author | Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> | 2017-02-27 15:30:25 +0300 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2017-03-10 21:23:34 +0300 |
| commit | ed46e66cc1b3d684042f92dfa2ab15ee917b4cac (patch) | |
| tree | a0307607cdfb450cabc1494fd2bc9945d967bdb3 /drivers/iommu/io-pgtable-arm.c | |
| parent | c1ae3cfa0e89fa1a7ecc4c99031f5e9ae99d9201 (diff) | |
| download | linux-ed46e66cc1b3d684042f92dfa2ab15ee917b4cac.tar.xz | |
iommu/io-pgtable-arm: Check for leaf entry before dereferencing it
Do a check for already installed leaf entry at the current level before
dereferencing it in order to avoid walking the page table down with
wrong pointer to the next level.
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'drivers/iommu/io-pgtable-arm.c')
| -rw-r--r-- | drivers/iommu/io-pgtable-arm.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c index feacc54bec68..f9bc6ebb8140 100644 --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -335,8 +335,12 @@ static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova, if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS) pte |= ARM_LPAE_PTE_NSTABLE; __arm_lpae_set_pte(ptep, pte, cfg); - } else { + } else if (!iopte_leaf(pte, lvl)) { cptep = iopte_deref(pte, data); + } else { + /* We require an unmap first */ + WARN_ON(!selftest_running); + return -EEXIST; } /* Rinse, repeat */ |