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From:   Miaohe Lin <linmiaohe@huawei.com>
To:     <akpm@linux-foundation.org>, <mike.kravetz@oracle.com>,
        <songmuchun@bytedance.com>
CC:     <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>,
        <linmiaohe@huawei.com>
Subject: [PATCH] hugetlb: fix memoryleak in hugetlb_mcopy_atomic_pte
Date:   Sat, 9 Jul 2022 17:26:29 +0800
Message-ID: <20220709092629.54291-1-linmiaohe@huawei.com>
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Precedence: bulk

When alloc_huge_page fails, *pagep is set to NULL without put_page first.
So the hugepage indicated by *pagep is leaked.

Fixes: 8cc5fcbb5be8 ("mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
 mm/hugetlb.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 06c2d86b1ba3..598c37279fee 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5962,6 +5962,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
 
 		page = alloc_huge_page(dst_vma, dst_addr, 0);
 		if (IS_ERR(page)) {
+			put_page(*pagep);
 			ret = -ENOMEM;
 			*pagep = NULL;
 			goto out;
-- 
2.23.0