From patchwork Wed Dec 18 04:47:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Liu X-Patchwork-Id: 13913019 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 60FB135974; Wed, 18 Dec 2024 04:47:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734497251; cv=none; b=Pp5O/mWkpnFnjlJLBEwI08FTcK5ePg6RN6AiMG8HELNQzjiJ2hnY5LxBE9u1GXMoTVqqCc8T/nJEoZxDEnnD5nG+RbOqPL/hFQRNd37i1/xE/90ZJ2RYrR6ZQ4R6EcKAV2snP9bmPGRy4mi/WxWBzktJjy+iFpCu2XcNTm38nRU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734497251; c=relaxed/simple; bh=N06FIWtq5f6afA0TvjPQ7CITRjH8zMnihpeOW6GSQgU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=pehAFYtb8ocJN9Omiw9uL3gKWeLGSI9Lr8aMk6wwMbY+rEZVB8qFfUovDWlGN8NR14t3r1Pir/mMVftwXzQc2tqCo+xJFs26qcQ4cs6JtRBrqowRw/e6Njaw0pY8QHXlEOOk5cuUvi5FBpccMHPGt7Jc0E5mGWWrc9/UviQz3GA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JRc0hi5j; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="JRc0hi5j" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 585EBC4CECE; Wed, 18 Dec 2024 04:47:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1734497251; bh=N06FIWtq5f6afA0TvjPQ7CITRjH8zMnihpeOW6GSQgU=; h=From:To:Cc:Subject:Date:From; b=JRc0hi5j00z2rkJgtsWsJEo9PKFJi7yhUxWNL/MgZMFCVwTxvU4NKT3z1l5R70Ezr f3Q8s2ZnS+F3kCFsvdQjw+jwP7J0ZB4oj6CKoIfa7Tj8nWsjTtUqz1bPFZmjG0TYEJ 8SAUU3cP3C0fOu6Z5YMneq4mVvLhq+i36HlGVIiK3U5hT6OwDZgCrzWVQpcWucB6/K 1rjorh8XdG1E5ba/Nv4PhxaZorKE+xvbhhq6Ida9ujR6xYzGqKVlHgi70WMrfdJpUz mVgWedev1cE+mq0j9dJ1/ycricihXZP0lwieBxBZLDXfrFJCHQjCY0S6RlCBjlsYkO tqOt6EdFp1gwQ== From: Song Liu To: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org Cc: kernel-team@meta.com, andrii@kernel.org, ast@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, kpsingh@kernel.org, mattbobrowski@google.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, memxor@gmail.com, Song Liu Subject: [PATCH v5 bpf-next 0/5] Enable writing xattr from BPF programs Date: Tue, 17 Dec 2024 20:47:06 -0800 Message-ID: <20241218044711.1723221-1-song@kernel.org> X-Mailer: git-send-email 2.43.5 Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add support to set and remove xattr from BPF program. Also add security.bpf. xattr name prefix. kfuncs are added to set and remove xattrs with security.bpf. name prefix. Update kfuncs bpf_get_[file|dentry]_xattr to read xattrs with security.bpf. name prefix. Note that BPF programs can read user. xattrs, but not write and remove them. Cover letter of v1 and v2: Follow up discussion in LPC 2024 [1], that we need security.bpf xattr prefix. This set adds "security.bpf." xattr name prefix, and allows bpf kfuncs bpf_get_[file|dentry]_xattr() to read these xattrs. [1] https://lpc.events/event/18/contributions/1940/ Changes v4 => v5 1. Let verifier pick proper kfunc (_locked or not _locked) based on the calling context. (Alexei) 2. Remove the __failure test (6/6 of v4). v4: https://lore.kernel.org/bpf/20241217063821.482857-1-song@kernel.org/ Changes v3 => v4 1. Do write permission check with inode locked. (Jan Kara) 2. Fix some source_inline warnings. v3: https://lore.kernel.org/bpf/20241210220627.2800362-1-song@kernel.org/ Changes v2 => v3 1. Add kfuncs to set and remove xattr from BPF programs. v2: https://lore.kernel.org/bpf/20241016070955.375923-1-song@kernel.org/ Changes v1 => v2 1. Update comment of bpf_get_[file|dentry]_xattr. (Jiri Olsa) 2. Fix comment for return value of bpf_get_[file|dentry]_xattr. v1: https://lore.kernel.org/bpf/20241002214637.3625277-1-song@kernel.org/ Song Liu (5): fs/xattr: bpf: Introduce security.bpf. xattr name prefix selftests/bpf: Extend test fs_kfuncs to cover security.bpf. xattr names bpf: lsm: Add two more sleepable hooks bpf: fs/xattr: Add BPF kfuncs to set and remove xattrs selftests/bpf: Test kfuncs that set and remove xattr from BPF programs fs/bpf_fs_kfuncs.c | 214 +++++++++++++++++- include/linux/bpf_lsm.h | 8 + include/uapi/linux/xattr.h | 4 + kernel/bpf/bpf_lsm.c | 2 + kernel/bpf/verifier.c | 55 ++++- tools/testing/selftests/bpf/bpf_kfuncs.h | 5 + .../selftests/bpf/prog_tests/fs_kfuncs.c | 162 ++++++++++++- .../selftests/bpf/progs/test_get_xattr.c | 28 ++- .../bpf/progs/test_set_remove_xattr.c | 133 +++++++++++ 9 files changed, 590 insertions(+), 21 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/test_set_remove_xattr.c --- 2.43.5