From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794662480; b=cEdv73HgkrECR2ts3tTtVv/1wUu9yVaHOilWTh+NfzGtVQ+hmjNj9NT3O6tMgS3KyDAT 86vQxSPlIHfJYY71dsztW4PpH1+ALHOBiHM76LReBv8vqtl59pw5SkvcCLXSAHCBeQqfa PQ/EOmkFoOxtW1dK3rOSfRyNh3kZCV3bfFlOfqKq32cUK1V62cmXsVmQk235L3tKGNNge hPH9u83DPdtVBl7hmyXAyN/p/OJkQ5awC9N6ZisB86HqSO99RV7dWTWzO/uXW87PjqHGc oLLws5zq5hIzq3Vu1hQcxFXQiDIq5bLMy56nPpcU5vxIKbl2rrUMvqf7mO3IHwWRmjA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794662480; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=xm3maFW+oMKNy+weeZrbl/H+YFEXCZUk3YE2LJJAPmA=; b=jy1tFyyE5oSNUU7Ep+/pkoptl246Mrj3Pw/h/7zqcFdNjWCzq1Bdy0a9ojGPYR0JwWwI Kpzg+2/M77VoFQa5dJvZXlsvTNDvYiWGSEurF1Cyn4DNqkYAtI2lg/NELBQRvX50vFHue yqbgJEE3XXF5oZXG5csIE+b07CjWWbiIp3KpF+i3ikweKmZpV2ciGNnoskA/6SUCgxEPj T/0rxUkV47xIGCKkVEvRBeMNehUp/sLygGQ679WjKa96dNEgwRj+A6mpr+ImBSXCztFtx TK/lFK+XIlDxDtlBOjP7I2dlhzVle8R/KIYg21cU7hltzmb2NGESsWxm3lthJ1UpjqQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ajaQzgId; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 41DDC606A327; Sat, 14 Nov 2026 13:21:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ajaQzgId Received: by smtp.kernel.org (Postfix) with ESMTPSA id 873F71F000C4; Sat, 14 Nov 2026 13:21:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794662480; bh=xm3maFW+oMKNy+weeZrbl/H+YFEXCZUk3YE2LJJAPmA=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=ajaQzgIdkkm7BSuZG/5h38p+6Adw7f8VGMm6ZCFJbIL8wow6lBTJ55fJfkIM2Y70R vd7kWeVSqsn6zK3ZkvgfvMiX4+DaU/MuhhjFXv4yOO0HK7Bbsz0HtDq40b8fp86b5U y3b2Q77zvIbA0kpaZN542FPgXaL+FRQGAg3EvShYziToeGzYw6Jic3ceejLKTtu34c aCSm8ziCuwq9Lso4ZwbpxlX2VCh3eiKQdIt2FzwEPElvOEJ5uXrBr/btSx1TiDWd7P 8K642+tKvgVdZcl0KtDtcEoijCvUqiN/p7PrsNGAagqxol0QTibygv2JZY8awCmIy/ sa6W5Nav3yHGA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH RFC v2 36/42] nvmet: refuse files on pseudo filesystems as namespace backing files Reply-To: sashiko-reviews@lists.linux.dev To: "Christian Brauner" Cc: linux-security-module@vger.kernel.org, selinux@vger.kernel.org, linux-s390@vger.kernel.org, linux-usb@vger.kernel.org, "Heiko Carstens" , "Vasily Gorbik" , "Alexander Gordeev" , "Christian Borntraeger" , "Mark Fasheh" , "Joel Becker" , "Joseph Qi" In-Reply-To: <20261114-work-loop-pseudo-v2-36-98639a2286fb@kernel.org> References: <20261114-work-loop-pseudo-v2-0-98639a2286fb@kernel.org> <20261114-work-loop-pseudo-v2-36-98639a2286fb@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Sat, 14 Nov 2026 13:21:19 +0000 X-Mailing-List: selinux@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > The file backend takes any file that can be opened for reading and > writing. With buffered_io=3D1 that includes files on procfs or sysfs which > then get read and written by a kernel worker on behalf of the host. > Refuse files on pseudo filesystems just like loop does by switching to > file_check_backing(). >=20 > Note that the helper only accepts regular files and block devices. A > block device ends up in the file backend when buffered_io is set. But > so far the file backend also took anything else with ->read_iter() and > ->write_iter() such as character devices and FIFOs. The size of the > namespace is the size of the inode which is zero for all of them. So > such a namespace was unusable anyway. Refuse them. >=20 > Signed-off-by: Christian Brauner (Amutable) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261114-work-loop-= pseudo-v2-0-98639a2286fb@kernel.org?part=3D36