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=1792778296; b=Gtf3yLksJ691yMTb/nrbvmKBKbPUzuIsYlNMVLUr6Th83srGftRT/abO50UayKj71x2P IK0J5Yj287FLcQUXEvel880fXvMs/OllN0ZstjNfhKw6NyOeDrNOQqHuDWRU+3nVCYBvp OWDrsdDSGX451MbPnRn8W3LuzV+8z9cCOe9cFp/S2JaYvYYeH3BZlQxna4Avgsjxigk1h triiHv3M4UHMLqLHy6XQsv99E92RLALAy4BZsBxwMhkT1gVU4Tfd1RDACUjDscVf0rMY3 /u5TCn44JgYoScAHBgPOgprtN+awCUZWE4N2vKxLJAJXDbsl+u2Fk9yqExTn4OObUng== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792778296; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=aaRu/xRSEKXEo00KqfWUyR2g6KT0ybLN+e0PUCUN0OQ=; b=JaQ7cF60n+/w+kmDdWFzxDC+LW2tCaXzjrnnpL3x3RIlJyj7nIPNoOEUPwFXHGUYiFZ+ RCtxKFLtkgm4UYhkIiOfsVeVOQDTnSg5Pw8Erb98gUjxQYVRy0BC4U5S324KkIISeBwe3 WjaYtc8hGezXAHnF6+nwLZP6iKLBrl7SKnj7bcw1mealER55emrn+KoIv/uMqoP9uk02l PvLnzFVOoi40Cbs54uh7zsrSCY/ojdo6Vi3iLM4hcVcUbgHfoDfqZMXAxCASMMjyb7rlI VFoWlsF6n188qSIys4u2GspRutFN+tzDF98mqxn31AHrCJM0zetcvDZ5QkZC6nGvYCQ== 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="a/pGS3i6"; 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 015D3606A31A for ; Fri, 23 Oct 2026 17:58:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=a/pGS3i6 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C96E1F01825; Fri, 23 Oct 2026 17:58:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792778295; bh=aaRu/xRSEKXEo00KqfWUyR2g6KT0ybLN+e0PUCUN0OQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=a/pGS3i6JO81P2c1fdsu5w9emhI2A0bbUVx4KiswXBsucbVvDat9Oo1RcmUJQmQx7 8A4skQ8pX7kooz8rfV2vw/r9Ayrb/hD4tU14bHfhi7XUl7XazNg9mKz70BgyebSGbl BbWwwkOZWk1UpM1TgBulsG6a+0L2Oo2I3BkOPiT+IyVYodeymgQ7WQt6G7lVtlHxg4 x0geIpc57BP5gt4Ecxy2/xksfnix1hF1onX0HXmlZWHziz7Qcy5XACKZryaAdDJvyK R844tXpZyj+eYYx+69nPsHOceaNnHImzdIrmaJP4+nQXs7WhedUn5TCDlZQobicryq VJxNGnZjLKMjg== Date: Fri, 23 Oct 2026 19:58:09 +0200 From: Alejandro Colomar To: Grayson Tinker Cc: linux-man@vger.kernel.org Subject: Re: [PATCH] man/man5/tmpfs.5: Specify that noswap may not be used within unprivileged user namespaces Message-ID: References: <20261020015112.127389-1-graysontinker@gmail.com> X-Mailing-List: linux-man@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="xicy4aosbyx24ybt" Content-Disposition: inline In-Reply-To: <20261020015112.127389-1-graysontinker@gmail.com> --xicy4aosbyx24ybt Content-Type: text/plain; protected-headers=v1; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable From: Alejandro Colomar To: Grayson Tinker Cc: linux-man@vger.kernel.org Subject: Re: [PATCH] man/man5/tmpfs.5: Specify that noswap may not be used within unprivileged user namespaces Message-ID: References: <20261020015112.127389-1-graysontinker@gmail.com> MIME-Version: 1.0 In-Reply-To: <20261020015112.127389-1-graysontinker@gmail.com> Hi Grayson, > Date: 2026-10-19 19:51:12-0600 > From: Grayson Tinker > > Since the tmpfs noswap option was added, the kernel has disallowed its us= e while > within an unprivileged user namespace for security reasons. Document this= restriction > so users do not believe noswap to be available in every situation. >=20 > ref. linux.git 01106e140835ff94fdef79d66f166b87b0c89824 ("shmem: restrict= noswap option to initial user namespace") >=20 > Signed-off-by: Grayson Tinker Thanks! I've applied the patch. Have a lovely night! Alex > --- > man/man5/tmpfs.5 | 4 ++++ > 1 file changed, 4 insertions(+) >=20 > diff --git a/man/man5/tmpfs.5 b/man/man5/tmpfs.5 > index 10acbdcfa..a904db2c8 100644 > --- a/man/man5/tmpfs.5 > +++ b/man/man5/tmpfs.5 > @@ -109,6 +109,10 @@ but not a % suffix. > Disables swap. > Remounts must respect the original settings. > By default swap is enabled. > +.IP > +.\" commit 01106e140835ff94fdef79d66f166b87b0c89824 > +.B noswap > +is not available while within an unprivileged user namespace. > .TP > .BR mode =3D\f[I]mode\f[] > Set initial permissions of the root directory. >=20 > Range-diff: > -: --------- > 1: b3b2becca man/man5/tmpfs.5: Specify that noswap may n= ot be used within unprivileged user namespaces > --=20 > 2.55.0 >=20 --=20 --xicy4aosbyx24ybt Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEES7Jt9u9GbmlWADAi64mZXMKQwqkFAmrboDEACgkQ64mZXMKQ wqmoFw/7BwznVvdNti1gKVIuk0KHF9p79qiOc6ys5vZy+JfdtmAeMVWTaamMR2Z9 nFaGDwFJbM7Buykhn/QUwAdt623MABrW61/D8VkWf1knZ8HgwhYUirGuLhDt/BRX s7+T7IG966EpdIvpg4+ZmiqgVfpPm2dCa5S+bsBu8fzze8Zw+dS7jTZuwLQAOwIW +9E36DeQvgP2c93CwJ8yIe6CwLTI2NprliVrfAWfqSyQEM3xruDgjTwdCPaydxeD jsSZKtEsldGZthZozwOzNNf4GuUVj9vyjdYywjnpWnFHrrp/lj8QzIA+7QjTWOMA JGI9jbdJlbWVe78HIPgrrjnzISIJcb1Pqh5hLCsic4Bmca7/cJOsAwDKsRCs0o/W Ht4Tz6wgbTslLQbanJZD+FSgrvQb5OS8AgcSrPmEDnEfOWMBREY2h7Q0qeaFRTlF VbZQIg3WssfWwjc9BdFQ6i7SCbzFQZU3kjDzVi/JaGCLZPVNeR+5ID7Y5RSIjEX1 TBXJA5sy7Ozbo5NP5C4uqoDzbMR6aaE9nCTW9mIRt2eXHshWtf7ElGlAW3HVSRjT 1zf67j82i9gK6hTfYTjPzYqifq/nzkQ2rSmcrPMP2eTnSFP8lXRqTRTijW9kWeK9 CseK0+3ABEzn8wNskZQsDGnPG6sF/or8PUBjlLxvUetEMsOT9rk= =fM67 -----END PGP SIGNATURE----- --xicy4aosbyx24ybt--