Commit d6ac235d authored by Suren Baghdasaryan's avatar Suren Baghdasaryan Committed by Andrew Morton
Browse files

mm/mremap: write-lock VMA while remapping it to a new address range 

Write-lock VMA as locked before copying it and when copy_vma produces a
new VMA.

Link: https://lkml.kernel.org/r/20230227173632.3292573-18-surenb@google.com


Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
Reviewed-by: default avatarLaurent Dufour <laurent.dufour@fr.ibm.com>
Reviewed-by: default avatarHyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 10fca64a

mm/mmap.c

+1 −0
Original line number Diff line number Diff line
@@ -3197,6 +3197,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, 
			get_file(new_vma->vm_file);

		if (new_vma->vm_ops && new_vma->vm_ops->open)

			new_vma->vm_ops->open(new_vma);

		vma_start_write(new_vma);

		if (vma_link(mm, new_vma))

			goto out_vma_link;

		*need_rmap_locks = false;

mm/mremap.c

+1 −0
Original line number Diff line number Diff line
@@ -623,6 +623,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, 
			return -ENOMEM;

	}



	vma_start_write(vma);

	new_pgoff = vma->vm_pgoff + ((old_addr - vma->vm_start) >> PAGE_SHIFT);

	new_vma = copy_vma(&vma, new_addr, new_len, new_pgoff,

			   &need_rmap_locks);