From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 04D791DACB1 for ; Wed, 2 Jul 2025 14:44:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751467449; cv=none; b=N9SPJxMmEJwl+ZBf7qMkmED1qvVmm4BEfFL0/EDA7KgnT0Y2TJBQTnlte5xFZF8kB+YTC0N+IVBmFYt7nQrRdwHstT0/OWweCczu8eJItW+HagtcFPbFKSM34qCAfPdhjIgM+GI59hQwPPHH89f7zhN7gsH2Uppfb/wMs05E+bg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751467449; c=relaxed/simple; bh=6Wb49X0BJHbqwWrkROi+YR+7r3jK71+OW26GsASEmwY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Lldzv2l57FN4BQpp4PnBv+AH0WSg613VACzZwBMgBToC73hB8Usezo+bIfXXHdPcdzYn/k1W8d2xh43DQZxmXjSkyJ02zgphDEdb0nzUOutV0q9hFhK7t1XHtuRQ/KLtvsEmTmrhNQPyGpix/T47HMSMToM2MCOljQeZA0BI8JI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=glBzfBPj; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="glBzfBPj" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1751467446; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=v5kZ8LByR5tDk+2RARWaEVx7RJMhvOELDCL82WVT4Mo=; b=glBzfBPjwTJoMLLS8WuByre84o4A3yZ6yRbphgVibZhvMhwDRHGKlrjQd0qzruaG9GIg+B EdOkidyAhRdeO2KrgcTQF5eSML+DzJ1dQ7ITMumVPlB8x0ad/FXENU2r/hrDYrvb4yVgwI 8MUCvZEKvkYevcW4F8wdmdTW4jNS+tw= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-649-mZHA4WJ-O2WYc1xxDP2HMg-1; Wed, 02 Jul 2025 10:44:05 -0400 X-MC-Unique: mZHA4WJ-O2WYc1xxDP2HMg-1 X-Mimecast-MFC-AGG-ID: mZHA4WJ-O2WYc1xxDP2HMg_1751467444 Received: by mail-wr1-f69.google.com with SMTP id ffacd0b85a97d-3af3c860ed7so1149413f8f.1 for ; Wed, 02 Jul 2025 07:44:04 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751467444; x=1752072244; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:cc:to:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=v5kZ8LByR5tDk+2RARWaEVx7RJMhvOELDCL82WVT4Mo=; b=VY/qSeK7tkxKb03vb/GC1DJOFVwvKkV2nc7XH7m8reFOJh78QPR4KZjQId3FF9Ce58 jn6VfVXYWxxiV1ubwJRDnPa/EM5z8FaQJPXS+ojQcgXkHq3SsgiBTwaHL1yy75yUIY+S 4m1JHWGq6mI/EO8iC+JAFgte9pJujTPBnpFULNwDFp5B8V+aLIDipL/6CN8ZdboGqV1A lzLSSNmCwuVLlsV5LBOYAyCkoIYwpnG09U2B22n3XtEZEznNn7yj3JuTJjA7bMsotw66 /jfBnVelYIln6XmMST+oQfk4GRKEnQ1CaJKnxvnNjPiT4AtqBPrw8kulLmgE92yy/j49 xvwg== X-Forwarded-Encrypted: i=1; AJvYcCWU6BAv0M38/1p5VEOXm7Vb2D8mbC8B2Wm4zkDWjWz/IXX4ef0jXd5wrmAf8mVIvu3aJqDaezZCm6yqRoM=@vger.kernel.org X-Gm-Message-State: AOJu0YxYNnDXrxeAcKxpzTvQhx27MBIp5ciWZ4ZbGOKAjEdAqhPef9QE Tn8cKW1vQv9MG0YLZ0oFYPuy3282Ve8Z1B7EJt/3GXM33pYzoBfUdV9acTo6yHnBLKRESCFPLsb 5Mb3sIptZ+bdBAyW62qgJgkXdi4ry8cm/JlHffG96yPc438rAf9S+uKNOMPg4DwYjlA== X-Gm-Gg: ASbGncuRMcB0fFZD1sv/4lVgmsu8H1hmc2UVtaefBcz1bkngy+dx/r6/vG7rPMBdQNs HdGCuDanjvM/JOYYbes9/EkyZF7Y9IRAzAq1e2wt7a5Dm6EJl1pIkJeZCLJ7aZXaknC1dQHhile HnNTv4lMW13ad0OyaZNBGLVljr86DqiH8J755msEZTaazKnWRVca+lXYHWLXcsaIOZ2yHtIQVvN 8SQf4a9jhH1j2+C3x9jggwimz5Rni1bmx4Wu4lH61KOo8kIp04cKyHPOESo5OBrD5GhU212OgR9 eEPoUhM7gXZn8aC8/JgYBBqOkMrG0mChOQxtT42IK/uB9vVJklYbiFg= X-Received: by 2002:adf:9b84:0:b0:3a4:f744:e00c with SMTP id ffacd0b85a97d-3b20095ce61mr1968565f8f.29.1751467443770; Wed, 02 Jul 2025 07:44:03 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFp7NbPcO7rJZWXvSnrni21vm6TsH+e1Wf8nuopye15pGumcNSxUt3JtyGqe+Gm1zDhsN9hOA== X-Received: by 2002:adf:9b84:0:b0:3a4:f744:e00c with SMTP id ffacd0b85a97d-3b20095ce61mr1968544f8f.29.1751467443279; Wed, 02 Jul 2025 07:44:03 -0700 (PDT) Received: from ?IPV6:2a09:80c0:192:0:5dac:bf3d:c41:c3e7? ([2a09:80c0:192:0:5dac:bf3d:c41:c3e7]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3a892e52a26sm16417581f8f.51.2025.07.02.07.44.02 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 02 Jul 2025 07:44:02 -0700 (PDT) Message-ID: <693725d9-a293-414f-a706-f77446e335b1@redhat.com> Date: Wed, 2 Jul 2025 16:44:01 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH next] mm/maps: move kmalloc() call location in do_procmap_query() out of RCU critical section To: Jeongjun Park , akpm@linux-foundation.org Cc: andrii@kernel.org, osalvador@suse.de, Liam.Howlett@Oracle.com, surenb@google.com, christophe.leroy@csgroup.eu, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, syzbot+6246a83e7bd9f8a3e239@syzkaller.appspotmail.com References: <20250702135332.291866-1-aha310510@gmail.com> From: David Hildenbrand Content-Language: en-US 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: <20250702135332.291866-1-aha310510@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 02.07.25 15:53, Jeongjun Park wrote: > In do_procmap_query(), we are allocating name_buf as much as name_buf_sz > with kmalloc(). > > However, due to the previous commit eff061546ca5 > ("mm/maps: execute PROCMAP_QUERY ioctl under per-vma locks"), > the location of kmalloc() is located inside the RCU critical section. > > This causes might_sleep_if() to be called inside the RCU critical section, > so we need to move the call location of kmalloc() outside the RCU critical > section to prevent this. > > Reported-by: syzbot+6246a83e7bd9f8a3e239@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=6246a83e7bd9f8a3e239 > Fixes: eff061546ca5 ("mm/maps: execute PROCMAP_QUERY ioctl under per-vma locks") That commit is not upstream yet (and the commit id is not stable), so it should be squashed into the problematic commit. As a side note: the patch subject of this and the original patch should start with "fs/proc/task_mmu", not "mm/maps". -- Cheers, David / dhildenb