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| author | Kefeng Wang <wangkefeng.wang@huawei.com> | 2024-10-28 22:56:56 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-12-18 19:04:42 -0800 |
| commit | f5d09de9f1bf9674c6418ff10d0a40cfe29268e1 (patch) | |
| tree | e04a8448059128b36640208d44d046fa71e9c526 /mm | |
| parent | 8aca2bc96c833ba695ede7a45ad7784c836a262e (diff) | |
| download | lwn-f5d09de9f1bf9674c6418ff10d0a40cfe29268e1.tar.gz lwn-f5d09de9f1bf9674c6418ff10d0a40cfe29268e1.zip | |
mm: use aligned address in copy_user_gigantic_page()
In current kernel, hugetlb_wp() calls copy_user_large_folio() with the
fault address. Where the fault address may be not aligned with the huge
page size. Then, copy_user_large_folio() may call
copy_user_gigantic_page() with the address, while
copy_user_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
copy_user_gigantic_page().
Link: https://lkml.kernel.org/r/20241028145656.932941-2-wangkefeng.wang@huawei.com
Fixes: 530dd9926dc1 ("mm: memory: improve copy_user_large_folio()")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Huang Ying <ying.huang@intel.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>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/hugetlb.c | 5 | ||||
| -rw-r--r-- | mm/memory.c | 5 |
2 files changed, 5 insertions, 5 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index ea2ed8e301ef..cec4b121193f 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5340,7 +5340,7 @@ again: break; } ret = copy_user_large_folio(new_folio, pte_folio, - ALIGN_DOWN(addr, sz), dst_vma); + addr, dst_vma); folio_put(pte_folio); if (ret) { folio_put(new_folio); @@ -6643,8 +6643,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, *foliop = NULL; goto out; } - ret = copy_user_large_folio(folio, *foliop, - ALIGN_DOWN(dst_addr, size), dst_vma); + ret = copy_user_large_folio(folio, *foliop, dst_addr, dst_vma); folio_put(*foliop); *foliop = NULL; if (ret) { diff --git a/mm/memory.c b/mm/memory.c index 84864387f965..209885a4134f 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -6852,13 +6852,14 @@ void folio_zero_user(struct folio *folio, unsigned long addr_hint) } static int copy_user_gigantic_page(struct folio *dst, struct folio *src, - unsigned long addr, + unsigned long addr_hint, struct vm_area_struct *vma, unsigned int nr_pages) { - int i; + unsigned long addr = ALIGN_DOWN(addr_hint, folio_size(dst)); struct page *dst_page; struct page *src_page; + int i; for (i = 0; i < nr_pages; i++) { dst_page = folio_page(dst, i); |