diff options
| author | Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> | 2017-02-27 14:30:25 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-08 10:14:19 +0200 |
| commit | 9bcd5ceef96e71d57795c593e4dacf767f935c79 (patch) | |
| tree | 671fea799ef7df60eb26b9a6d8edea769328968c /drivers/iommu | |
| parent | cadfa3a688d2f1f618677ddc66cb4f5cdbae6a81 (diff) | |
iommu/io-pgtable-arm: Check for leaf entry before dereferencing it
[ Upstream commit ed46e66cc1b3d684042f92dfa2ab15ee917b4cac ]
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.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 dad768caa9c5..18751b1dfd3d 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 */ |