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[2003:cb:c702:bf00:abf6:cc3a:24d6:fa55]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-42286fe9263sm29998255e9.15.2024.06.12.08.27.47 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 12 Jun 2024 08:27:48 -0700 (PDT) Message-ID: <541d1a37-7d3f-4f9a-b4d8-572aacd96f1e@redhat.com> Date: Wed, 12 Jun 2024 17:27:47 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] mm: fix possible OOB in numa_rebuild_large_mapping() To: Kefeng Wang , Andrew Morton Cc: ying.huang@intel.com, Baolin Wang , linux-mm@kvack.org, John Hubbard , Mel Gorman , Ryan Roberts , liushixin2@huawei.com References: <20240612122822.4033433-1-wangkefeng.wang@huawei.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: <20240612122822.4033433-1-wangkefeng.wang@huawei.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 7A50E40009 X-Stat-Signature: 5uqjat75uti5w6ap93im18756b1cubqa X-HE-Tag: 1718206073-927824 X-HE-Meta: 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 NDst9djy poxWiWCUN9reRU0xAxzOjFAwD4z0P99KnDK/ynA0Xv6ltb3V7PP/K/YPcvNXib+wOi7Q/DU16GCmSdY+UOp6X/L9BZ3t9ASxM3VpoI/sUZPLhRGZagO1LPjG3jA557E9sVQ5Vae7r/FFFgtGX26NFRnYxpKsQbnHSg49RISIi6WxaSpjbunm4yBl6GgvthovjsVNfUBnpCWfbMIkvCfEJqOTr22OFADND/e5zlpvyvpY9Ncdz3UF5l1VySCPtXumjh3sJ8habu3uDic9vFCGrSeJ/1zLf8/TcWnX5JC/G88le7IZ44+3f/HxSDXfX5i9pSwW0EZL0T5v4KNhL2tUZ9imT5KETQtK5CpnrHNfHcCNe6zWPPKKGRg/cq2TEtKhcVVo74JYGnFlaPNwNqsOrXuQQDzMMWWpDEdbFXlpUMH773VE= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 12.06.24 14:28, Kefeng Wang wrote: > The large folio is mapped with folio size(not greater PMD_SIZE) aligned > virtual address during the pagefault, ie, 'addr = ALIGN_DOWN(vmf->address, > nr_pages * PAGE_SIZE)' in do_anonymous_page(). But after the mremap(), > the virtual address only requires PAGE_SIZE alignment. Also pte is moved > to new in move_page_tables(), then traversal of the new pte in the > numa_rebuild_large_mapping() could hit the following issue, > > Unable to handle kernel paging request at virtual address 00000a80c021a788 > Mem abort info: > ESR = 0x0000000096000004 > EC = 0x25: DABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > FSC = 0x04: level 0 translation fault > Data abort info: > ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 > CM = 0, WnR = 0, TnD = 0, TagAccess = 0 > GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 > user pgtable: 4k pages, 48-bit VAs, pgdp=00002040341a6000 > [00000a80c021a788] pgd=0000000000000000, p4d=0000000000000000 > Internal error: Oops: 0000000096000004 [#1] SMP > ... > CPU: 76 PID: 15187 Comm: git Kdump: loaded Tainted: G W 6.10.0-rc2+ #209 > Hardware name: Huawei TaiShan 2280 V2/BC82AMDD, BIOS 1.79 08/21/2021 > pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : numa_rebuild_large_mapping+0x338/0x638 > lr : numa_rebuild_large_mapping+0x320/0x638 > sp : ffff8000b41c3b00 > x29: ffff8000b41c3b30 x28: ffff8000812a0000 x27: 00000000000a8000 > x26: 00000000000000a8 x25: 0010000000000001 x24: ffff20401c7170f0 > x23: 0000ffff33a1e000 x22: 0000ffff33a76000 x21: ffff20400869eca0 > x20: 0000ffff33976000 x19: 00000000000000a8 x18: ffffffffffffffff > x17: 0000000000000000 x16: 0000000000000020 x15: ffff8000b41c36a8 > x14: 0000000000000000 x13: 205d373831353154 x12: 5b5d333331363732 > x11: 000000000011ff78 x10: 000000000011ff10 x9 : ffff800080273f30 > x8 : 000000320400869e x7 : c0000000ffffd87f x6 : 00000000001e6ba8 > x5 : ffff206f3fb5af88 x4 : 0000000000000000 x3 : 0000000000000000 > x2 : 0000000000000000 x1 : fffffdffc0000000 x0 : 00000a80c021a780 > Call trace: > numa_rebuild_large_mapping+0x338/0x638 > do_numa_page+0x3e4/0x4e0 > handle_pte_fault+0x1bc/0x238 > __handle_mm_fault+0x20c/0x400 > handle_mm_fault+0xa8/0x288 > do_page_fault+0x124/0x498 > do_translation_fault+0x54/0x80 > do_mem_abort+0x4c/0xa8 > el0_da+0x40/0x110 > el0t_64_sync_handler+0xe4/0x158 > el0t_64_sync+0x188/0x190 > > Fix it by making the start and end not only within the vma range, but > also within the page table range. > > Fixes: d2136d749d76 ("mm: support multi-size THP numa balancing") > Signed-off-by: Kefeng Wang > --- > v2: > - don't pass nr_pages into numa_rebuild_large_mapping() > - address comment and suggestion from David > > mm/memory.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > > diff --git a/mm/memory.c b/mm/memory.c > index 0d309cfb703c..60f7a05ad0cd 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -5228,10 +5228,16 @@ static void numa_rebuild_large_mapping(struct vm_fault *vmf, struct vm_area_stru > bool ignore_writable, bool pte_write_upgrade) > { > int nr = pte_pfn(fault_pte) - folio_pfn(folio); > - unsigned long start = max(vmf->address - nr * PAGE_SIZE, vma->vm_start); > - unsigned long end = min(vmf->address + (folio_nr_pages(folio) - nr) * PAGE_SIZE, vma->vm_end); > - pte_t *start_ptep = vmf->pte - (vmf->address - start) / PAGE_SIZE; > - unsigned long addr; > + unsigned long start, end, addr = vmf->address; > + unsigned long addr_start = addr - (nr << PAGE_SHIFT); > + unsigned long pt_start = ALIGN_DOWN(addr, PMD_SIZE); > + pte_t *start_ptep; > + > + /* Stay within the VMA and within the page table. */ > + start = max3(addr_start, pt_start, vma->vm_start); > + end = min3(addr_start + folio_size(folio), pt_start + PMD_SIZE, > + vma->vm_end); > + start_ptep = vmf->pte - ((addr - start) >> PAGE_SHIFT); > > /* Restore all PTEs' mapping of the large folio */ > for (addr = start; addr != end; start_ptep++, addr += PAGE_SIZE) { Should do the trick, hopefully ;) Acked-by: David Hildenbrand -- Cheers, David / dhildenb