From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
---
arch/x86/entry/vdso/vma.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 235a5794296a..c0b160a9585d 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -128,15 +128,19 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
struct mm_struct *mm = task->mm;
struct vm_area_struct *vma;
+ MA_STATE(mas, &mm->mm_mt, 0, 0);
+
mmap_read_lock(mm);
+ rcu_read_lock();
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ mas_for_each(&mas, vma, ULONG_MAX) {
unsigned long size = vma->vm_end - vma->vm_start;
if (vma_is_special_mapping(vma, &vvar_mapping))
zap_page_range(vma, vma->vm_start, size);
}
+ rcu_read_unlock();
mmap_read_unlock(mm);
return 0;
}
@@ -354,6 +358,7 @@ int map_vdso_once(const struct vdso_image *image, unsigned long addr)
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
+ MA_STATE(mas, &mm->mm_mt, 0, 0);
mmap_write_lock(mm);
/*
@@ -363,13 +368,16 @@ int map_vdso_once(const struct vdso_image *image, unsigned long addr)
* We could search vma near context.vdso, but it's a slowpath,
* so let's explicitly check all VMAs to be completely sure.
*/
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ mas_lock(&mas);
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (vma_is_special_mapping(vma, &vdso_mapping) ||
vma_is_special_mapping(vma, &vvar_mapping)) {
+ mas_unlock(&mas);
mmap_write_unlock(mm);
return -EEXIST;
}
}
+ mas_unlock(&mas);
mmap_write_unlock(mm);
return map_vdso(image, addr);
--
2.30.2
