From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 838534409; Tue, 15 Oct 2024 05:07:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728968823; cv=none; b=Bp12kjbr0NeQ3lzdvFW9t0q0u3nX3/EuHPiNmUHUoNdtufLn5GSpUtini4Xm/e7K3sv4ae9DWrpQPaZxqB1DJ+FGUn5e9Wunki/4OIW1EdpEmTZ5mX/uLB8zw649Fv4NZFEQvKWTCLZCauzgl4aYq+wWNlCY93joTlLKXvdaNQM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728968823; c=relaxed/simple; bh=y1bijim7KlOGaI1ex/rUIONGaO9ypMdpazMW81g0y44=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qvCsWcuPuSA9ia6IYZwYAN4bK0UfujuThrrQBUIdMnS3Xc2PgV2VOECs/w0BMqc/89/tREry1F2R97hd+v9xLhUljJgqEE6daLvCEnp8wyATR0lfhX/2ZMRFjUWYuGqQ3fTYXBq0Zn5c8QUtVBw1AeG3GahkCBZU95/w8aJ6YjI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=gYPBXpC7; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="gYPBXpC7" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Vdd/N/H/gZ9ZTAqpv8rIHR89YOMK7NFLE+bbZiJgO5o=; b=gYPBXpC74S7yn+Lv+QzdsLA+ZD 3h19h8fDUL9+Lcs+vCjx6xYXMJAn2VJspa2T/hJG090BSdliwC8ICv027sHkc00kZ5rWPwyYzrNP9 SNCuvUpPZKFS6bRlR9O8wlUlFn+5hojksdCd18P84IX2nkfpj/YkojDSjBJjMlt8QeODjOEsYdMJb ZucREtXgwMl8BQjzGH+ALLS6X3/72Yu97PM1zL+R4JHoc7nm4JHI/QASyShv1BOfep8xbd/n9MoMl x5Zo7o7K4bDZPLhrjjnGQKm9YLmwN8QVvuTi0W1BQj64lOa5tC97Jk/qeU9yd6xzb7gtUH2ImlsDy MdfjnOVQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1t0Zls-000000075Dr-2wOl; Tue, 15 Oct 2024 05:07:00 +0000 Date: Mon, 14 Oct 2024 22:07:00 -0700 From: Christoph Hellwig To: Song Liu Cc: bpf@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, andrii@kernel.org, eddyz87@gmail.com, ast@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, kpsingh@kernel.org, mattbobrowski@google.com Subject: Re: [PATCH bpf-next 2/2] selftests/bpf: Extend test fs_kfuncs to cover security.bpf xattr names Message-ID: References: <20241002214637.3625277-1-song@kernel.org> <20241002214637.3625277-3-song@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241002214637.3625277-3-song@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Wed, Oct 02, 2024 at 02:46:37PM -0700, Song Liu wrote: > Extend test_progs fs_kfuncs to cover different xattr names. Specifically: > xattr name "user.kfuncs", "security.bpf", and "security.bpf.xxx" can be > read from BPF program with kfuncs bpf_get_[file|dentry]_xattr(); while > "security.bpfxxx" and "security.selinux" cannot be read. So you read code from untrusted user.* xattrs? How can you carve out that space and not known any pre-existing userspace cod uses kfuncs for it's own purpose?