Revert "arm64: Introduce execute-only page access permissions"
This reverts commit bc07c2c6e9ed125d362af0214b6313dca180cb08.
While the aim is increased security for --x memory maps, it does not
protect against kernel level reads. Until SECCOMP is implemented for
arm64, revert this patch to avoid giving a false idea of execute-only
mappings.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 89c6763..bcc965e 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -173,7 +173,8 @@
good_area:
/*
* Check that the permissions on the VMA allow for the fault which
- * occurred.
+ * occurred. If we encountered a write or exec fault, we must have
+ * appropriate permissions, otherwise we allow any permission.
*/
if (!(vma->vm_flags & vm_flags)) {
fault = VM_FAULT_BADACCESS;
@@ -195,7 +196,7 @@
struct task_struct *tsk;
struct mm_struct *mm;
int fault, sig, code;
- unsigned long vm_flags = VM_READ | VM_WRITE;
+ unsigned long vm_flags = VM_READ | VM_WRITE | VM_EXEC;
unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
tsk = current;