iommu/io-pgtable-arm: Check for leaf entry before dereferencing it
authorOleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Mon, 27 Feb 2017 12:30:25 +0000 (14:30 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 8 Oct 2017 08:14:19 +0000 (10:14 +0200)
commit9bcd5ceef96e71d57795c593e4dacf767f935c79
tree671fea799ef7df60eb26b9a6d8edea769328968c
parentcadfa3a688d2f1f618677ddc66cb4f5cdbae6a81
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>
drivers/iommu/io-pgtable-arm.c