[125/192] mm/memory.c: use vma_lookup() in __access_remote_vm()

Commit Message

Andrew Morton June 29, 2021, 2:39 a.m. UTC

From: Liam Howlett <[e-mail]>
Subject: mm/memory.c: use vma_lookup() in __access_remote_vm()

Use vma_lookup() to find the VMA at a specific address.  As vma_lookup()
will return NULL if the address is not within any VMA, the start address
no longer needs to be validated.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Liam R. Howlett <[e-mail]>
Reviewed-by: Laurent Dufour <[e-mail]>
Acked-by: David Hildenbrand <[e-mail]>
Acked-by: Davidlohr Bueso <[e-mail]>
Cc: Geert Uytterhoeven <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 mm/memory.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Patch

--- a/mm/memory.c~mm-memoryc-use-vma_lookup-in-__access_remote_vm
+++ a/mm/memory.c
@@ -4994,8 +4994,8 @@  int __access_remote_vm(struct mm_struct
 			 * Check if this is a VM_IO | VM_PFNMAP VMA, which
 			 * we can access using slightly different code.
 			 */
-			vma = find_vma(mm, addr);
-			if (!vma || vma->vm_start > addr)
+			vma = vma_lookup(mm, addr);
+			if (!vma)
 				break;
 			if (vma->vm_ops && vma->vm_ops->access)
 				ret = vma->vm_ops->access(vma, addr, buf,