Commit ccf1d78d authored by Suren Baghdasaryan's avatar Suren Baghdasaryan Committed by Andrew Morton
Browse files

mm/mmap: move vma_prepare before vma_adjust_trans_huge 

vma_prepare() acquires all locks required before VMA modifications.  Move
vma_prepare() before vma_adjust_trans_huge() so that VMA is locked before
any modification.

Link: https://lkml.kernel.org/r/20230227173632.3292573-15-surenb@google.com


Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent c7322933

mm/mmap.c

+5 −5
Original line number Diff line number Diff line
@@ -683,12 +683,12 @@ int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma, 
	if (vma_iter_prealloc(vmi))

		goto nomem;



	vma_prepare(&vp);

	vma_adjust_trans_huge(vma, start, end, 0);

	/* VMA iterator points to previous, so set to start if necessary */

	if (vma_iter_addr(vmi) != start)

		vma_iter_set(vmi, start);



	vma_prepare(&vp);

	vma->vm_start = start;

	vma->vm_end = end;

	vma->vm_pgoff = pgoff;
@@ -723,8 +723,8 @@ int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma, 
		return -ENOMEM;



	init_vma_prep(&vp, vma);

	vma_adjust_trans_huge(vma, start, end, 0);

	vma_prepare(&vp);

	vma_adjust_trans_huge(vma, start, end, 0);



	if (vma->vm_start < start)

		vma_iter_clear(vmi, vma->vm_start, start);
@@ -1010,12 +1010,12 @@ struct vm_area_struct *vma_merge(struct vma_iterator *vmi, struct mm_struct *mm, 
	if (vma_iter_prealloc(vmi))

		return NULL;



	vma_adjust_trans_huge(vma, vma_start, vma_end, adj_start);

	init_multi_vma_prep(&vp, vma, adjust, remove, remove2);

	VM_WARN_ON(vp.anon_vma && adjust && adjust->anon_vma &&

		   vp.anon_vma != adjust->anon_vma);



	vma_prepare(&vp);

	vma_adjust_trans_huge(vma, vma_start, vma_end, adj_start);

	if (vma_start < vma->vm_start || vma_end > vma->vm_end)

		vma_expanded = true;
@@ -2214,10 +2214,10 @@ int __split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, 
	if (new->vm_ops && new->vm_ops->open)

		new->vm_ops->open(new);



	vma_adjust_trans_huge(vma, vma->vm_start, addr, 0);

	init_vma_prep(&vp, vma);

	vp.insert = new;

	vma_prepare(&vp);

	vma_adjust_trans_huge(vma, vma->vm_start, addr, 0);



	if (new_below) {

		vma->vm_start = addr;
@@ -2920,9 +2920,9 @@ static int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma, 
		if (vma_iter_prealloc(vmi))

			goto unacct_fail;



		vma_adjust_trans_huge(vma, vma->vm_start, addr + len, 0);

		init_vma_prep(&vp, vma);

		vma_prepare(&vp);

		vma_adjust_trans_huge(vma, vma->vm_start, addr + len, 0);

		vma->vm_end = addr + len;

		vm_flags_set(vma, VM_SOFTDIRTY);

		vma_iter_store(vmi, vma);