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Received: from CH3PR12MB8403.namprd12.prod.outlook.com (2603:10b6:610:133::14) by SJ2PR12MB8875.namprd12.prod.outlook.com (2603:10b6:a03:543::13) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7002.17; Thu, 16 Nov 2023 21:46:03 +0000 Received: from CH3PR12MB8403.namprd12.prod.outlook.com ([fe80::e2:9f06:b82e:9a0f]) by CH3PR12MB8403.namprd12.prod.outlook.com ([fe80::e2:9f06:b82e:9a0f%3]) with mapi id 15.20.7002.019; Thu, 16 Nov 2023 21:46:03 +0000 Message-ID: Date: Thu, 16 Nov 2023 15:46:00 -0600 User-Agent: Mozilla Thunderbird Subject: Re: [RESEND v5 2/4] fs: debugfs: Add write functionality to debugfs blobs Content-Language: en-US To: "Luck, Tony" Cc: "rafael@kernel.org" , "lenb@kernel.org" , "james.morse@arm.com" , "bp@alien8.de" , "gregkh@linuxfoundation.org" , "linux-fsdevel@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "alexey.kardashevskiy@amd.com" , "yazen.ghannam@amd.com" , Avadhut Naik , "linux-acpi@vger.kernel.org" References: <20231107213647.1405493-1-avadhut.naik@amd.com> <20231107213647.1405493-3-avadhut.naik@amd.com> <71ad8b0e-984b-4739-a940-82c5a1456f50@amd.com> From: Avadhut Naik In-Reply-To: Content-Type: text/plain; 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Does that sound good? > > You need write access. I don't think you need to be root. E.g. a validation system might > set up an "einj" group and "chmod" all these files to 0664. But that's nitpicking. > >> >> In any case, using 0666 will result in the below checkpatch warning: >> >> [root avadnaik-linux]# ./scripts/checkpatch.pl --strict -g HEAD >> WARNING: Exporting world writable files is usually an error. Consider more restrictive permissions. >> #84: FILE: fs/debugfs/file.c:1063: >> + return debugfs_create_file_unsafe(name, mode & 0666, parent, blob, &fops_blob); >> >> total: 0 errors, 1 warnings, 0 checks, 54 lines checked > > The warning is dubious. This code isn't necessarily exporting a world writeable file. But > it does allow a caller of this routine to do that. > >> >> Would you be okay with s/0444/0644/? > >> - return debugfs_create_file_unsafe(name, mode & 0444, parent, blob, &fops_blob); >> + return debugfs_create_file_unsafe(name, mode & 0644, parent, blob, &fops_blob); > > > Yes. This is fine (better). Make sure to mention in the commit comment that this allows > callers to create files writeable by owner. > Will do. Thanks for the confirmation! > -Tony > > -- Thanks, Avadhut Naik