nommu configuration has two places where vma gets attached to the vma tree without write-locking it. Add the missing locks to ensure vma is always locked before it's attached. Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx> --- mm/nommu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/nommu.c b/mm/nommu.c index 72c8c505836c..1754e84e5758 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1189,6 +1189,7 @@ unsigned long do_mmap(struct file *file, goto error_just_free; setup_vma_to_mm(vma, current->mm); + vma_start_write(vma); current->mm->map_count++; /* add the VMA to the tree */ vma_iter_store(&vmi, vma, true); @@ -1356,6 +1357,7 @@ static int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, setup_vma_to_mm(vma, mm); setup_vma_to_mm(new, mm); + vma_start_write(new); vma_iter_store(vmi, new, true); mm->map_count++; return 0; -- 2.47.1.613.gc27f4b7a9f-goog
