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d=ucw.cz; s=gen1; t=1714120444; 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: in-reply-to:in-reply-to:references:references; bh=QvibUhHYADzPBz5EC0L11wDXL1jTgRw8iSeBq8eHVAM=; b=r1+96OokA5XnKcE0vuf1HJX1Ft1NJRMVXB5Y6SoF6NZ+LhN73MJbxf6L6vZMvey5Kjcj0e 9cOjaBw82DXwSN7HFQyB9TyKY1Q/O16uAIueJST+3SO64nnoP8t+r5PZ+EVeT1RVPuI9a7 2Vj+jc1gpnbG7eTWMr9PAYK0TEF4RsA= Date: Fri, 26 Apr 2024 10:34:03 +0200 From: Pavel Machek To: Matthew Wilcox Cc: Kent Overstreet , Kees Cook , Andrew Morton , Suren Baghdasaryan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] alloc_tag: Tighten file permissions on /proc/allocinfo Message-ID: References: <20240425200844.work.184-kees@kernel.org> <64cngpnwyav4odustofs6hgsh7htpc5nu23tx4lb3vxaltmqf2@sxn63f2gg4gu> <202404251532.F8860056AE@keescook> <20240425164718.e8e187dd0c5b0a87371d8316@linux-foundation.org> <202404251740.81F21E54@keescook> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Hfd8D8Tcgbk/y9Re" Content-Disposition: inline In-Reply-To: --Hfd8D8Tcgbk/y9Re Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri 2024-04-26 04:25:40, Matthew Wilcox wrote: > On Thu, Apr 25, 2024 at 08:58:34PM -0400, Kent Overstreet wrote: > > On Thu, Apr 25, 2024 at 05:43:33PM -0700, Kees Cook wrote: > > > All this said, I'm still not excited about any of these files living > > > in /proc at all -- we were supposed to use /sys for this kind of thin= g, > > > but its interface wasn't great for this kind of more "free-form" data, > > > and debugfs isn't good for production interfaces. /proc really should > > > only have pid information -- we end up exposing these top-level files= to > > > every mount namespace with a /proc mount. :( But that's a yet-to-be-s= olved > > > problem... > >=20 > > It really wouldn't be that hard to relax the 4k file limit in sysfs. >=20 > It's a lot harder to relax the GregKH opposition to multiple values per > file in sysfs. With all the "vulnerability" files including multiple-files with english text, you may be able to renegotiate that :-). Joking, really the vulnerability files should be fixed. Pavel --=20 People of Russia, stop Putin before his war on Ukraine escalates. --Hfd8D8Tcgbk/y9Re Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABECAB0WIQRPfPO7r0eAhk010v0w5/Bqldv68gUCZitm+wAKCRAw5/Bqldv6 8ll4AJ9jdqA72f4HoYEdP44jUJtvFz4NiwCfS7dHjbTz44v8yKIi6pQk9qVCu6s= =C7Pf -----END PGP SIGNATURE----- --Hfd8D8Tcgbk/y9Re--