diff options
| author | Miaohe Lin <linmiaohe@huawei.com> | 2021-09-03 00:58:22 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-03 19:58:15 +0300 |
| commit | ea3732f7a1cf636284388988d1a1e56d5cba6044 (patch) | |
| tree | b10edd0c45d46b87164a0804425a4da66e46ed5c | |
| parent | ae611d072c5c2968e2cc29431cf58094d8971b94 (diff) | |
| download | linux-ea3732f7a1cf636284388988d1a1e56d5cba6044.tar.xz | |
mm/hwpoison: fix potential pte_unmap_unlock pte error
If the first pte is equal to poisoned_pfn, i.e. check_hwpoisoned_entry()
return 1, the wrong ptep - 1 would be passed to pte_unmap_unlock().
Link: https://lkml.kernel.org/r/20210814105131.48814-3-linmiaohe@huawei.com
Fixes: ad9c59c24095 ("mm,hwpoison: send SIGBUS with error virutal address")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/memory-failure.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 9793c78c3777..224bd0be223c 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -632,7 +632,7 @@ static int hwpoison_pte_range(pmd_t *pmdp, unsigned long addr, { struct hwp_walk *hwp = (struct hwp_walk *)walk->private; int ret = 0; - pte_t *ptep; + pte_t *ptep, *mapped_pte; spinlock_t *ptl; ptl = pmd_trans_huge_lock(pmdp, walk->vma); @@ -645,14 +645,15 @@ static int hwpoison_pte_range(pmd_t *pmdp, unsigned long addr, if (pmd_trans_unstable(pmdp)) goto out; - ptep = pte_offset_map_lock(walk->vma->vm_mm, pmdp, addr, &ptl); + mapped_pte = ptep = pte_offset_map_lock(walk->vma->vm_mm, pmdp, + addr, &ptl); for (; addr != end; ptep++, addr += PAGE_SIZE) { ret = check_hwpoisoned_entry(*ptep, addr, PAGE_SHIFT, hwp->pfn, &hwp->tk); if (ret == 1) break; } - pte_unmap_unlock(ptep - 1, ptl); + pte_unmap_unlock(mapped_pte, ptl); out: cond_resched(); return ret; |