evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

iommu/io-pgtable-arm: Check for leaf entry before dereferencing it

Browse source 
[ 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>
This commit is contained in:
Oleksandr Tyshchenko 2017-02-27 14:30:25 +02:00 • committed by Greg Kroah-Hartman
parent cadfa3a688
commit 9bcd5ceef9
1 changed files with 5 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
drivers/iommu/io-pgtable-arm.c
View file

@ -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) if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
pte |= ARM_LPAE_PTE_NSTABLE; pte |= ARM_LPAE_PTE_NSTABLE;
__arm_lpae_set_pte(ptep, pte, cfg); __arm_lpae_set_pte(ptep, pte, cfg);
} else { } else if (!iopte_leaf(pte, lvl)) {
cptep = iopte_deref(pte, data); cptep = iopte_deref(pte, data);
} else {
/* We require an unmap first */
WARN_ON(!selftest_running);
return -EEXIST;
} }
/* Rinse, repeat */ /* Rinse, repeat */