diff options
| author | Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> | 2017-02-27 14:30:26 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-20 10:07:19 +0100 |
| commit | 3d40364d333e3de4cc2e49c80ad8ddb242c46315 (patch) | |
| tree | 2903741286b40f106b11e3ed2755923b436ded29 /drivers/iommu | |
| parent | 721c136ac2780e519cd44940ba47f08cdeafec9d (diff) | |
iommu/io-pgtable-arm-v7s: Check for leaf entry before dereferencing it
[ Upstream commit a03849e7210277fa212779b7cd9c30e1ab6194b2 ]
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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/io-pgtable-arm-v7s.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c index f50e51c1a9c8..d68a552cfe8d 100644 --- a/drivers/iommu/io-pgtable-arm-v7s.c +++ b/drivers/iommu/io-pgtable-arm-v7s.c @@ -418,8 +418,12 @@ static int __arm_v7s_map(struct arm_v7s_io_pgtable *data, unsigned long iova, pte |= ARM_V7S_ATTR_NS_TABLE; __arm_v7s_set_pte(ptep, pte, 1, cfg); - } else { + } else if (ARM_V7S_PTE_IS_TABLE(pte, lvl)) { cptep = iopte_deref(pte, lvl); + } else { + /* We require an unmap first */ + WARN_ON(!selftest_running); + return -EEXIST; } /* Rinse, repeat */ |