arm64/efi: Clear PTE_WRITE when applying EFI_MEMORY_RO

set_permissions() sets PTE_RDONLY for regions that the Memory Attributes
Table describes as read-only, but leaves PTE_WRITE set.  PTE_WRITE is
the DBM bit, so when hardware dirty state management is enabled
(TCR_EL1.HD), such a descriptor is writable-clean rather than read-only,
and a write by the firmware will be permitted by the hardware (which
marks the entry dirty) instead of faulting.

Clear PTE_WRITE as well, as pte_wrprotect() does.

Cc: stable@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

0 files changed, 0 insertions, 0 deletions