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Diffstat (limited to 'arch/powerpc/mm/fault.c')
-rw-r--r--arch/powerpc/mm/fault.c48
1 files changed, 45 insertions, 3 deletions
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 2bef19cc1b98..531177a4ee08 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -271,11 +271,16 @@ static bool access_error(bool is_write, bool is_exec, struct vm_area_struct *vma
}
/*
- * Check for a read fault. This could be caused by a read on an
- * inaccessible page (i.e. PROT_NONE), or a Radix MMU execute-only page.
+ * VM_READ, VM_WRITE and VM_EXEC all imply read permissions, as
+ * defined in protection_map[]. Read faults can only be caused by
+ * a PROT_NONE mapping, or with a PROT_EXEC-only mapping on Radix.
*/
- if (unlikely(!(vma->vm_flags & VM_READ)))
+ if (unlikely(!vma_is_accessible(vma)))
return true;
+
+ if (unlikely(radix_enabled() && ((vma->vm_flags & VM_ACCESS_FLAGS) == VM_EXEC)))
+ return true;
+
/*
* We should ideally do the vma pkey access check here. But in the
* fault path, handle_mm_fault() also does the same check. To avoid
@@ -469,6 +474,40 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address,
if (is_exec)
flags |= FAULT_FLAG_INSTRUCTION;
+#ifdef CONFIG_PER_VMA_LOCK
+ if (!(flags & FAULT_FLAG_USER))
+ goto lock_mmap;
+
+ vma = lock_vma_under_rcu(mm, address);
+ if (!vma)
+ goto lock_mmap;
+
+ if (unlikely(access_pkey_error(is_write, is_exec,
+ (error_code & DSISR_KEYFAULT), vma))) {
+ vma_end_read(vma);
+ goto lock_mmap;
+ }
+
+ if (unlikely(access_error(is_write, is_exec, vma))) {
+ vma_end_read(vma);
+ goto lock_mmap;
+ }
+
+ fault = handle_mm_fault(vma, address, flags | FAULT_FLAG_VMA_LOCK, regs);
+ vma_end_read(vma);
+
+ if (!(fault & VM_FAULT_RETRY)) {
+ count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
+ goto done;
+ }
+ count_vm_vma_lock_event(VMA_LOCK_RETRY);
+
+ if (fault_signal_pending(fault, regs))
+ return user_mode(regs) ? 0 : SIGBUS;
+
+lock_mmap:
+#endif /* CONFIG_PER_VMA_LOCK */
+
/* When running in the kernel we expect faults to occur only to
* addresses in user space. All other faults represent errors in the
* kernel and should generate an OOPS. Unfortunately, in the case of an
@@ -545,6 +584,9 @@ retry:
mmap_read_unlock(current->mm);
+#ifdef CONFIG_PER_VMA_LOCK
+done:
+#endif
if (unlikely(fault & VM_FAULT_ERROR))
return mm_fault_error(regs, address, fault);