From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 1C83C471409; Tue, 21 Jul 2026 17:51:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784656285; cv=none; b=mqb5V1+LED6a9I9hYlW4XrP65fy0sl0/6qjt0OeawCJDrjaSMyy7kjiDOOzSpJcpLdlC1AsinBR22W3oVkA++HwfZ0lkubVNVet0GlGaQMf26wBrD0Wzapqxguu7RFrVwAC06/Hkhp96vfcsRwoVvfOBs3nNVNacmlkey1FGhvM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784656285; c=relaxed/simple; bh=qRXs6gEj2RCCVRrSwZ67qr3bcLciCN6i7c2PCN6WkdA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=fK8bye8k86u1WNXkPHjAgT8bXBngVLUHBnvaqjXEZCjoxCKOdvy/PLu3Farv0qLdW5WsEBxYEjL18PK0suqRWr1nqr0D4lDTS8cb5AZxUOmhFPvafbTB1MZ47K48Dzg0EvGtnLoxZISw+qy1kzH+w2eGS4FoBoYoxv44AGbYDDw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MNzt4Bog; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="MNzt4Bog" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 841551F000E9; Tue, 21 Jul 2026 17:51:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784656284; bh=1PfzzCZkvd0zkv/UcEjxUc1/4Xnb1uAmiidzmZF+0iI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=MNzt4Bog6f2sVXLA/PLvP5Xy28R1+E9MfV95YtyexAZfY3YXr9jJ4Y152dnKhVnte BB3faPwD9DFwtrwYh3LgRdX4MbL/Yxf7W0HaAL5iPZiKKUP67/vc+UM5tpbY1e+AsP 37jZbo5FZ7Mpm9UDZ8KKLFZ3qebhz00tPvMnFjHA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Maciej=20=C5=BBenczykowski?= , Lorenzo Colitti , Yuyang Huang , Alexei Starovoitov , Sasha Levin Subject: [PATCH 6.18 0286/1611] selftests/bpf: add verification for BPF_PROG_QUERY attr size boundaries Date: Tue, 21 Jul 2026 17:06:42 +0200 Message-ID: <20260721152521.492507532@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152514.750365251@linuxfoundation.org> References: <20260721152514.750365251@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yuyang Huang [ Upstream commit 5add3a4ad1a3bc15404e8bd338813ed0a636f5c9 ] Add a new selftest to verify that the BPF syscall (specifically BPF_PROG_QUERY) correctly handles different user-declared attribute sizes. Specifically, verify that: - For cgroup queries, a query with a size that covers 'prog_cnt' but is smaller than 'revision' (OLD_QUERY_SIZE) succeeds, but does not write to 'revision' (verifying backward compatibility). - A query with full size (FULL_QUERY_SIZE) succeeds and writes both 'prog_cnt' and 'revision'. Fixes: 120933984460 ("bpf: Implement mprog API on top of existing cgroup progs") Cc: Maciej Żenczykowski Cc: Lorenzo Colitti Signed-off-by: Yuyang Huang Link: https://lore.kernel.org/r/20260531075600.4058207-3-yuyanghuang@google.com Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- .../selftests/bpf/prog_tests/bpf_attr_size.c | 69 +++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/bpf_attr_size.c diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_attr_size.c b/tools/testing/selftests/bpf/prog_tests/bpf_attr_size.c new file mode 100644 index 00000000000000..32159dc64da8b0 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/bpf_attr_size.c @@ -0,0 +1,69 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2026 Google LLC */ +#include +#include +#include +#include +#include +#include "cgroup_skb_direct_packet_access.skel.h" + +#define OLD_QUERY_SIZE offsetofend(union bpf_attr, query.prog_cnt) +#define FULL_QUERY_SIZE offsetofend(union bpf_attr, query.revision) + +static void test_query_size_boundaries(void) +{ + struct cgroup_skb_direct_packet_access *skel; + struct bpf_link *link = NULL; + union bpf_attr attr; + int cg_fd = -1; + int err; + + skel = cgroup_skb_direct_packet_access__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel_load")) + return; + + cg_fd = test__join_cgroup("/attr_size_cg"); + if (!ASSERT_GE(cg_fd, 0, "join_cgroup")) + goto cleanup; + + link = bpf_program__attach_cgroup(skel->progs.direct_packet_access, + cg_fd); + if (!ASSERT_OK_PTR(link, "cg_attach")) + goto cleanup; + + memset(&attr, 0, sizeof(attr)); + attr.query.target_fd = cg_fd; + attr.query.attach_type = BPF_CGROUP_INET_INGRESS; + attr.query.revision = 0xdeadbeefdeadbeefULL; + + err = syscall(__NR_bpf, BPF_PROG_QUERY, &attr, OLD_QUERY_SIZE); + if (ASSERT_OK(err, "query_old_size")) { + ASSERT_EQ(attr.query.prog_cnt, 1, "prog_cnt_written_old"); + ASSERT_EQ(attr.query.revision, 0xdeadbeefdeadbeefULL, + "revision_not_written_old"); + } + + memset(&attr, 0, sizeof(attr)); + attr.query.target_fd = cg_fd; + attr.query.attach_type = BPF_CGROUP_INET_INGRESS; + + err = syscall(__NR_bpf, BPF_PROG_QUERY, &attr, FULL_QUERY_SIZE); + if (!ASSERT_OK(err, "query_full_size")) + goto cleanup; + + ASSERT_EQ(attr.query.prog_cnt, 1, "prog_cnt_written"); + ASSERT_GT(attr.query.revision, 0, "revision_written"); + +cleanup: + if (link) + bpf_link__destroy(link); + if (cg_fd >= 0) + close(cg_fd); + cgroup_skb_direct_packet_access__destroy(skel); +} + +void test_bpf_attr_size(void) +{ + if (test__start_subtest("query_size_boundaries")) + test_query_size_boundaries(); +} -- 2.53.0