From: Rik van Riel <riel@xxxxxxxxxxx>
Hugetlbfs leaves a dangling pointer in the VMA if mmap fails.
This has not been a problem so far, but other code in this patch
series tries to follow that pointer.
Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Signed-off-by: Rik van Riel <riel@xxxxxxxxxxx>
Cc: stable@xxxxxxxxxx
Fixes: 04ada095dcfc ("hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing")
---
mm/hugetlb.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ba6d39b71cb1..a86e070d735b 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1138,8 +1138,7 @@ static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map)
VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma);
VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma);
- set_vma_private_data(vma, (get_vma_private_data(vma) &
- HPAGE_RESV_MASK) | (unsigned long)map);
+ set_vma_private_data(vma, (unsigned long)map);
}
static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags)
@@ -6806,8 +6805,10 @@ bool hugetlb_reserve_pages(struct inode *inode,
*/
if (chg >= 0 && add < 0)
region_abort(resv_map, from, to, regions_needed);
- if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER))
+ if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
kref_put(&resv_map->refs, resv_map_release);
+ set_vma_resv_map(vma, NULL);
+ }
return false;
}
--
2.41.0
