From e77a9be11193f7f8fdbad75351fce39090261ad5 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Fri, 10 Jun 2022 21:42:02 -0700 Subject: [PATCH] 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. Signed-off-by: Suren Baghdasaryan Reviewed-by: Laurent Dufour --- mm/mmap.c | 1 + mm/mremap.c | 1 + 2 files changed, 2 insertions(+) diff --git a/mm/mmap.c b/mm/mmap.c index ae585a6287ea..eeb8b098443a 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -3267,6 +3267,7 @@ 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_write_lock(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 e7093def4760..2c3e2a0540d4 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -622,6 +622,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, return -ENOMEM; } + vma_write_lock(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); -- 2.50.1