From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.3]) (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 5353C3B27C6; Tue, 22 Sep 2026 02:55:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.3 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790045731; cv=none; b=YGSXzCob1x16Rf3YiYhCaiNQb5qWFtidkx3leDdPJMRAutY9gVGHPzums7YUDteDHcDSXEpyzekgpwgPK2+TUdsRZR59Zhylvtaii9GwV/EBfbTgnvlumL08lO313QPNzCCPavIh3NzY8QT4l4uhw85+wC2NYMBdM/Qnm6kd6Mk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790045731; c=relaxed/simple; bh=+7tk65VehXfxdW/hJz5YnXEKaDRQhunCVmEtXDvuLSg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=feJv52DMTdIWEzMx4vldAVcseC6Ld0zAHd8XnJnqeESoSoN70sJHZwDtLntBBv/3gYWVK73jiUlJvhCqQWH61W3e5ODdqD6tG7EaVvi/TjITkEulhxzfaEmCU0oRoo5HLflJ76QjIOKPVlij1jRbrmVhC9oWL5Jl02ho1dn+XCg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=KJ6+18KJ; arc=none smtp.client-ip=220.197.31.3 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="KJ6+18KJ" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=vl kyJfsgylXlYUWQ2UWwJsTEdH4rKHN0ZElZoFLMfkg=; b=KJ6+18KJkW2LVVH234 PpZ4ACc+3fFo8HQupPsTz2+SjIysMgPn62KO/lxrjFIMFURFS/nzoZpIelakCuTD kOyw69RSxEzSB0gy5ki1ht/GdMpnzJ0sAb6PY+Sf8YZd85YoUa9rB6dPFZBVkosK pE28PRC+GNV/wugCu/J70fne8= Received: from localhost (unknown []) by gzsmtp5 (Coremail) with SMTP id QCgvCgCn8HP07bFqT6riAg--.6728S2; Tue, 22 Sep 2026 10:54:45 +0800 (CST) From: Hui Su To: bpf@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Kumar Kartikeya Dwivedi Cc: Yonghong Song , Quentin Monnet , Martin KaFai Lau , Song Liu , Jiri Olsa , Emil Tsalapatis , Ihor Solodrai , Shuah Khan , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Hui Su Subject: [PATCH bpf-next v3 1/3] bpf: Report BPF_F_PREORDER in cgroup program queries Date: Tue, 22 Sep 2026 11:54:40 +0900 Message-ID: <20260922025442.3176057-2-sh_def@163.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260922025442.3176057-1-sh_def@163.com> References: <20260922025442.3176057-1-sh_def@163.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:QCgvCgCn8HP07bFqT6riAg--.6728S2 X-Coremail-Antispam: 1Uf129KBjvJXoW7AF4xCryftw47JrWfZrW7CFg_yoW8Cw17pF s5XFW7K3Wjvryaqw40g34FvrW0g3Z3XF1UCF9xG34fuayagr18tr9akFW5CFy5trZxCr10 vF90vr4Ygr1jvF7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0zioq2tUUUUU= X-CM-SenderInfo: xvkbvvri6rljoofrz/xtbC6hW-H2qx7fXSfwAA3x Extend direct cgroup program queries to merge (pl->flags & BPF_F_PREORDER) with the cgroup-wide flags when copying prog_attach_flags to user space. Only BPF_F_PREORDER is extracted from pl->flags to ensure transient positioning flags (such as BPF_F_BEFORE, BPF_F_AFTER, BPF_F_ID, or BPF_F_REPLACE) are not leaked to user space. This can introduce new prog_attach_flags[] values with BPF_F_PREORDER set, for example 0x40 (BPF_F_PREORDER), 0x41 (BPF_F_ALLOW_OVERRIDE | BPF_F_PREORDER), or 0x42 (BPF_F_ALLOW_MULTI | BPF_F_PREORDER), depending on the cgroup-wide attachment mode. Older bpftool versions treat such combinations as unknown flags; bpftool support is updated later in this series. Signed-off-by: Hui Su --- Notes (bpf-preorder-v3-20260922-check): Testing: - PASS: ./test_progs -t cgroup_mprog_opts (x86_64 QEMU/KVM). - Result reused after a content-equivalent rebase; the patch diff is unchanged. kernel/bpf/cgroup.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 1cb5e6a6ffc1..2bbe77de89f0 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -1515,19 +1515,19 @@ static int __cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr, id = prog_list_id(pl); if (copy_to_user(prog_ids + i, &id, sizeof(id))) return -EFAULT; + if (prog_attach_flags) { + flags = cgrp->bpf.flags[atype] | + (pl->flags & BPF_F_PREORDER); + if (copy_to_user(prog_attach_flags + i, + &flags, sizeof(flags))) + return -EFAULT; + } if (++i == cnt) break; } - if (prog_attach_flags) { - flags = cgrp->bpf.flags[atype]; - - for (i = 0; i < cnt; i++) - if (copy_to_user(prog_attach_flags + i, - &flags, sizeof(flags))) - return -EFAULT; + if (prog_attach_flags) prog_attach_flags += cnt; - } } prog_ids += cnt; -- 2.55.0