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=1793210865; b=ZMXNRbXtRNSdYE87hz401e8Tj/Gb37d2tvuDYhG79MB5Lqb7I65vr3UHOF/T6sjSKkKP cTjOdBsELZpL6uYoPW5ZaIhQN+xIyyIFEXr8kEpjYsZ/W7ivSl1zhQVAm9uoSfUx072z1 ujV7xmMn4iHM6FkEaw6HzqShzkROdU6C9gOlEw+B7kUAYk1R0H2xqRhRlir/EuAmqdJPV Ybo7wJYcvCHGDqkbUEBJemd3DPkOncTvRizjfsZ49ukU08NEdsLPTLSfhdgTjfwM1MAGv EtSIh73buaPs4iRT19JYQccta811mGsOUXqkiqcnvY0Oazd6RKmGlUdFp0PHVmwRAIA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793210865; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=1QymhgOg/76tJKj+piGg4eRtQ0QyG1Y+W8oL9ZVUd0s=; b=xFB8fiX3y9YcJWvna/tk4RyIBrI82fMAp3Yl/B6eG1ddbnecfhVJgjRayTtyvaAdElsz CdXgiVUbhXWF+hDhbdnilOylTVCf8FWFdZkjnITSL+AijSL06Eg6K0U1UfrRYm0zCe9Qd /F1xeuAG4AY77aM9qPJXfVrnf08BkuH3LJz9tvT6H4sYSJGF47qlZW8TaD0dk9oYlwonk OFh/xZYBBi3xYwNvg0iqh94w6Q4iQWkhERiwXESWY3cwzcUawMVitENIaBQJfM4WvXNk4 QN/dipqFIBrstcoe8uTNn3RjNhyPxoGP6fvv2V8r/zZ2+85Ri/h+eM6zJvq7JNjBTPg== 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=B2MBID+h; 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 B4E8A606A31A; Wed, 28 Oct 2026 18:07:44 +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=B2MBID+h Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B63C1F01825; Wed, 28 Oct 2026 18:07:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793210864; bh=1QymhgOg/76tJKj+piGg4eRtQ0QyG1Y+W8oL9ZVUd0s=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=B2MBID+h5JXphOHFX4EjjP5TGNlc2R/fSyqoRU9W9KNvjSp7JIstOtAxppz9j49wa +TwFNSs79rS5qKmO08xnqr9p89KK2NeIsdRKgEwMlIMV+hgIyvNTMq6sNSmeW9fmvO 4ik8PWQP3XaGr9QMwBbtSyAvm6rSs8Ui+CA+mDhxKm9BE5UfN1WI+Q6yQT0/f7EQtL WdEK/w6psIVF6nkrFHO7ro26OVvH46YVNgaW2dHjsyPJxWg3UCs7+20rwE48zGS2ue tmagc6CXl1YtkosYW44oqYa1MT8oxzt6iV+0/VFEpDWJa0BA5pOa7BT8uJtsGIgd7w ftDck6ngIk+Tw== Date: Wed, 28 Oct 2026 11:07:42 -0700 From: Eric Biggers To: fsverity@lists.linux.dev Cc: linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, Christoph Hellwig , stable@vger.kernel.org Subject: Re: [PATCH] fsverity: Set S_VERITY only after rollback is no longer possible Message-ID: <20261028180742.GD1876@quark> References: <20261025204807.122875-1-ebiggers@kernel.org> X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261025204807.122875-1-ebiggers@kernel.org> On Sun, Oct 25, 2026 at 01:48:07PM -0700, Eric Biggers wrote: > However, ext4 and btrfs can roll back verity after they set S_VERITY, > causing a use-after-free. > > Fix that by making ext4 and btrfs set S_VERITY only after rollback is no > longer possible. On failure, don't roll back S_VERITY, but do roll back > the filesystem-specific verity flag. Applied to https://git.kernel.org/pub/scm/fs/fsverity/linux.git/log/?h=for-current Acks from the ext4 and btrfs maintainers would be appreciated. - Eric