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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?fya20NtotSRyjKEI61RGLA+q2U/D51K8DaqTfM/bxEKPbNDbBxoylNE1qUvA?= =?us-ascii?Q?9f9yBN/0UswZ0tii5sfvME4IHZEILgYSM29QbgGrEAjymqWarzTzj2DwI7gE?= =?us-ascii?Q?8fL5X9E9mmh/FY3DAxZ4/q2VXTqrZbT6xb37ZxeCuY6KsKLfTwG77Dl3+uB7?= =?us-ascii?Q?XCm/jbkGy/WwP530g+u27ZsF8x7ONj78vafn1iQf4tOsGG6NtARLMCE4GtW6?= =?us-ascii?Q?Ma0CkWC16NXFo/VaJTDzcZxRUx7rCcgnTKgNOwyOTnp8g9LEu1kLkIjHUFxw?= =?us-ascii?Q?V9pnHTxDGBvuztE9J/FhUrVqDHjzaZSBJ84wJ7owjXGKh0ZfrQoP0vqmIGCa?= =?us-ascii?Q?+iPzVyE3wfeZ0JJOt2tZ8FJAJ8M2KVYbJS8d77Pkm1j69PNjyS1prud0Lpof?= =?us-ascii?Q?+wFe835W/1dbeF8kKdeQzD2s2JO3Kb3pGRduUIrWsOQiol2W/454VZJtpqYR?= =?us-ascii?Q?lwpIxUQILblpeiRkLZFMpf8K5/4Cm8dhQdoTqH/nRKJ4cDuY36rQbDgcgJSK?= =?us-ascii?Q?6VElf8j6bXvMyCcBXLnNdj5J9XR55rlFWqnIOn/c0MUt3mv2QGb8L+ecRrZ2?= =?us-ascii?Q?WXivVGdXf5bwBkYbMXU3EdfbkMUVikmwFRLKPHmxJnbCiR5S/danOzAAp1fn?= =?us-ascii?Q?s1u0tJUq0YEXREwkuwxYq/NcGGgEYfjYsw30F2hmDhrjoE8YMnJo/lF0ck8X?= =?us-ascii?Q?oTXjNmHFrqd+fSumBfhdjFnBD8WKOJ0q/bya30fjWe0RX5HYUM4dRgXFsKkH?= =?us-ascii?Q?3f/EDMY8B2PcQSYEBbv9PFLk8pHADYPopygzCo68AIVa3exU96tdS+Lj9vAS?= =?us-ascii?Q?cVUXuALe0eWHfCLAxO28ztrtHmQ7KvPQeHnLmnyL7x1qdWDry2w36oyVsHgp?= =?us-ascii?Q?QvO85eFRfakIhxqqMGMyJ7e+cq9kOgqKu4SxIc0nlDNPbkAmvhSKDbVnC6ra?= =?us-ascii?Q?pHpG24F85vk4HXjF75jW1DtNvm39n3SiNp9iAz4PQO5O+sWixV0AEWGB/5lT?= =?us-ascii?Q?0zllHdqcRpbukJ/QI35FpAsZh4W8zAF1ifoRGPpuUl4KY1/W3sJeVP3ADVKC?= =?us-ascii?Q?WZ2cdkZh/TGqXFk+Ezj2FyeXfs+ZC4Yjq0QTx61/s8Rc97OPmIpd8wcr/54M?= =?us-ascii?Q?dZlKkUlKMski2LOIZS7J0rp1LMe0C8/mvtf1kaKgG11cG/6XLmjWKqqpJanr?= =?us-ascii?Q?In00vcFkR/OFAkRdjwpgXba5o1XMcTNxUybZVT+qGZ/qKJ8qslYyt9LI8P0t?= =?us-ascii?Q?NabszSe5Ude4QNn8rO9O1CSCD+jnDPtlmDq7B0OYc1a1FPGQQYSpNoUENv0W?= =?us-ascii?Q?3sjj7NHgqRrnVW24UY8rS/xrphInpYdZqpIxuwczuWR/kMlAm8273yrOwfDE?= =?us-ascii?Q?y/NAPqr2rPF+zHE8X3aLi3c7I09mZTFBdksK+aQIg/cdQuUoIYPrsUAJRYlS?= =?us-ascii?Q?bazD5suVyCf0fTyLibus636mEqvmIsPfl/1n7z9exoHdsUTlANTeFNBt/i0J?= =?us-ascii?Q?JFC4aLD1L8M/XWbxTvRX911PrflU8nCGSNp0r+DLf4OqfGCXNHC5E5/QQYK5?= =?us-ascii?Q?sxGN8N4Q9pC6xzTftrkS7YNJNMqLiNV9RNh/nsuX?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d53ea4d6-85c5-40b7-004f-08dbb4c92e81 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB5744.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Sep 2023 02:20:36.5922 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: tsNmGDk5LSy771iOfPR+k8ZYJQIdPnc0Hp8++wvyNNzTT7g18+WC4sa85ZLnhvuR X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB6554 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=_MailMate_74C351E6-48C1-42FF-9A9C-4ACD7EF1135C_= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On 13 Sep 2023, at 16:12, Zi Yan wrote: > From: Zi Yan > > When dealing with hugetlb pages, manipulating struct page pointers > directly can get to wrong struct page, since struct page is not guarant= eed > to be contiguous on SPARSEMEM without VMEMMAP. Use nth_page() to handle= > it properly. > > Fixes: 57a196a58421 ("hugetlb: simplify hugetlb handling in follow_page= _mask") > Cc: > Signed-off-by: Zi Yan > Reviewed-by: Muchun Song > --- > mm/hugetlb.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index af74e83d92aa..8e68e6c53e66 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -6469,7 +6469,7 @@ struct page *hugetlb_follow_page_mask(struct vm_a= rea_struct *vma, > } > } > > - page +=3D ((address & ~huge_page_mask(h)) >> PAGE_SHIFT); > + page =3D nth_page(page, ((address & ~huge_page_mask(h)) >> PAGE_SHIF= T)); > > /* > * Note that page may be a sub-page, and with vmemmap > -- = > 2.40.1 A wrong or non-existing page might be tried to be grabbed, either leading= to a non freeable page or kernel memory access errors. No bug is reported. It comes from code inspection. -- Best Regards, Yan, Zi --=_MailMate_74C351E6-48C1-42FF-9A9C-4ACD7EF1135C_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEE6rR4j8RuQ2XmaZol4n+egRQHKFQFAmUCbe8PHHppeUBudmlk aWEuY29tAAoJEOJ/noEUByhUW50P/0q0HmZLnLMGBOXlPnpTJwjbaMv+1xcVjt+P bemMuWmxqORchNyBXRed0jzkaDe/f/IFRt5Ft6BPV3iBH1/Km1c26xhhHI+RNvBu 2T5Yy598b8SZgB+LqCk4htj7GVjA9PSpolkEKHqKjcIRHn11EQDLpo+pAy1CvDPf lFRwNqBcIlWcd2pBGWuzZSghPRziY5l6qJOFk6QSC+tL22va3zx/YxWZtKNWWxuU 3zosiUMnlPtcCv9NCgjiOXsiEzz6STdwjCx+Ihp5p7+WT52ypI2i/s4tcXOzs9JW MVkfKeaniodnEIuZTsykMYuLqvsubi74eKOrO1NP0VwHCXrcsQiKfDlGmgAfqECL MzUx32wQtF2BiS5yL0qrMf7/W8eOWwWT4Pm2JwGUcmfCeRU153D9mGpIW6CtgzQE 7KzRhFqGM/VNnqGFjFrZnbaM3NyqzKI2p5QuXQ4EaV1mJFvDPOGG5UfgmkCA/VON B3b3El/nycroPSJKXvtLc7nyE5oKReBzkuwKgxm6Y7TTBH6tH+nR9dy6WuzZTiOv m66Xvl+xqf1M2CrzAD9Vzdsn3cpqlXiNPN+MfZQCnghDcElHgqlhyCkAX1eFynTv wKynwlIfS0bi+7XRNBWbW+/VA4hHURRn+CY2HkFVEQrbW7wQPp07r4Wu77BlNdl3 6RNqr8fr =I0h5 -----END PGP SIGNATURE----- --=_MailMate_74C351E6-48C1-42FF-9A9C-4ACD7EF1135C_=--