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| author | Kefeng Wang <wangkefeng.wang@huawei.com> | 2024-10-28 22:56:55 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-12-18 19:04:42 -0800 |
| commit | 8aca2bc96c833ba695ede7a45ad7784c836a262e (patch) | |
| tree | 42029e980fc3487e203e0741321e7d385f7bd412 | |
| parent | dad2dc9c92e0f93f33cebcb0595b8daa3d57473f (diff) | |
| download | lwn-8aca2bc96c833ba695ede7a45ad7784c836a262e.tar.gz lwn-8aca2bc96c833ba695ede7a45ad7784c836a262e.zip | |
mm: use aligned address in clear_gigantic_page()
In current kernel, hugetlb_no_page() calls folio_zero_user() with the
fault address. Where the fault address may be not aligned with the huge
page size. Then, folio_zero_user() may call clear_gigantic_page() with
the address, while clear_gigantic_page() requires the address to be huge
page size aligned. So, this may cause memory corruption or information
leak, addtional, use more obvious naming 'addr_hint' instead of 'addr' for
clear_gigantic_page().
Link: https://lkml.kernel.org/r/20241028145656.932941-1-wangkefeng.wang@huawei.com
Fixes: 78fefd04c123 ("mm: memory: convert clear_huge_page() to folio_zero_user()")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | fs/hugetlbfs/inode.c | 2 | ||||
| -rw-r--r-- | mm/memory.c | 3 |
2 files changed, 3 insertions, 2 deletions
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 90f883d6b8fd..fc1ae5132127 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -825,7 +825,7 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset, error = PTR_ERR(folio); goto out; } - folio_zero_user(folio, ALIGN_DOWN(addr, hpage_size)); + folio_zero_user(folio, addr); __folio_mark_uptodate(folio); error = hugetlb_add_to_page_cache(folio, mapping, index); if (unlikely(error)) { diff --git a/mm/memory.c b/mm/memory.c index 75c2dfd04f72..84864387f965 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -6815,9 +6815,10 @@ static inline int process_huge_page( return 0; } -static void clear_gigantic_page(struct folio *folio, unsigned long addr, +static void clear_gigantic_page(struct folio *folio, unsigned long addr_hint, unsigned int nr_pages) { + unsigned long addr = ALIGN_DOWN(addr_hint, folio_size(folio)); int i; might_sleep(); |