Write-lock VMA as locked before copying it and when copy_vma produces a new VMA. Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx> Reviewed-by: Laurent Dufour <laurent.dufour@xxxxxxxxxx> --- mm/mmap.c | 1 + mm/mremap.c | 1 + 2 files changed, 2 insertions(+) diff --git a/mm/mmap.c b/mm/mmap.c index f079e5bbcd57..0eaa3d1a6cd1 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -3202,6 +3202,7 @@ 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; diff --git a/mm/mremap.c b/mm/mremap.c index 411a85682b58..dd541e59edda 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -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); -- 2.39.1
