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Howlett" , x86@kernel.org References: <94c35e89-f915-4122-b1a0-436893201373@stanley.mountain> <92c40df4-2e93-40ca-929e-a0b50ab2b631@redhat.com> 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: <92c40df4-2e93-40ca-929e-a0b50ab2b631@redhat.com> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: CxQl6_dXiXz-FtA3WVXdy1OCpjjxSIpttmhXeQHTo4E_1743769649 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: rspam03 X-Rspamd-Queue-Id: 494CA2000A X-Stat-Signature: frqxhzhjz7z8rr1rcpgajp549qws6u3a X-HE-Tag: 1743769654-28163 X-HE-Meta: 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 Jv3+7+Ib etY+QBhk9GbE8Lh4EZnRD4rrDZgxLv6XizP4e4sNYKvyAWwNrdTthS4TAL2NasZuLgPu78fuowZZ3CzIjH/k/xcYJs/efQrrmfGhkRzpLLiiElyxUQO7eAFczXg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, 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 04.04.25 14:20, David Hildenbrand wrote: > On 04.04.25 13:52, Lorenzo Stoakes wrote: >> On Thu, Apr 03, 2025 at 10:59:12PM +0200, David Hildenbrand wrote: >>> On 03.04.25 17:14, Dan Carpenter wrote: >>>> Sorry, I've been having trouble with my email recently... I replied >>>> earlier but my email got eaten on the way out. >>>> >>>> What happened here is that the zero day bot emails go to me first and >>>> then I review them or forward them depending on if they're a real >>>> issue or not. >>>> >>>> Here it's a false postive because it's set and used if the >>>> (src_vma->vm_flags & VM_PFNMAP) flag is set. Smatch doesn't parse >>>> this correctly. I've been meaning to fix this in Smatch for a >>>> while. >>> >>> There is a slight complication (on top of the VM_PFNMAP checks): >>> >>> If "src_vma->vm_flags & VM_PAT" we >>> * set pfn >>> * set dst_vma->vm_flags |= VM_PFNMAP >>> >>> Then, we only consume the pfn if "dst_vma->vm_flags & VM_PFNMAP" >>> >>> While we won't be using the uninitialized pfn (good), we'd still pass an >>> uninitialized pfn, which IIRC is UB; likely nothing happens on GCC clang, >>> but we better handle it. >>> >>> So that should better be changed; I'll send a fix. >> >> Maybe just worth setting pfn = 0 _as well_ in the caller, belts + braces maybe? > > I'm planning on doing the following, just didn't get to testing it: > Ah, now I get your comment. Yeah, we could just set pfn=0 in the caller as well to make smatch completely happy I guess. -- Cheers, David / dhildenb