From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9971FC4332F for ; Mon, 24 Jan 2022 22:17:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1582898AbiAXWQF (ORCPT ); Mon, 24 Jan 2022 17:16:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53302 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1453889AbiAXVbI (ORCPT ); Mon, 24 Jan 2022 16:31:08 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13214C0A893A; Mon, 24 Jan 2022 12:19:58 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id C43DCB8122C; Mon, 24 Jan 2022 20:19:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9A5AC340E5; Mon, 24 Jan 2022 20:19:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643055595; bh=rISzfO/DwKslH0NWHGM+V6cir+6QSkvk9BZL5LLR0cQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=afQGDGhPIvd4baQLstkA3So3yYzrp2EgZ40w0qtQy3AhXokzLwjrheqoOPND4plJU FAaVFfFL0shr8aIhzbQ1oS9C+kgDvK8f4Dj9DOIiLBoal3mgkwqKwdbJ5RYFkkQkLI wnRPS8DpuTuYOchKg3uNY6DtT3wBjr7pxWbIbAHg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hou Tao , Alexei Starovoitov , Yonghong Song , Martin KaFai Lau , Sasha Levin Subject: [PATCH 5.15 202/846] bpf: Disallow BPF_LOG_KERNEL log level for bpf(BPF_BTF_LOAD) Date: Mon, 24 Jan 2022 19:35:19 +0100 Message-Id: <20220124184107.906960330@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124184100.867127425@linuxfoundation.org> References: <20220124184100.867127425@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Hou Tao [ Upstream commit 866de407444398bc8140ea70de1dba5f91cc34ac ] BPF_LOG_KERNEL is only used internally, so disallow bpf_btf_load() to set log level as BPF_LOG_KERNEL. The same checking has already been done in bpf_check(), so factor out a helper to check the validity of log attributes and use it in both places. Fixes: 8580ac9404f6 ("bpf: Process in-kernel BTF") Signed-off-by: Hou Tao Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20211203053001.740945-1-houtao1@huawei.com Signed-off-by: Sasha Levin --- include/linux/bpf_verifier.h | 7 +++++++ kernel/bpf/btf.c | 3 +-- kernel/bpf/verifier.c | 6 +++--- 3 files changed, 11 insertions(+), 5 deletions(-) diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index 5424124dbe365..364550dd19c4a 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -396,6 +396,13 @@ static inline bool bpf_verifier_log_needed(const struct bpf_verifier_log *log) log->level == BPF_LOG_KERNEL); } +static inline bool +bpf_verifier_log_attr_valid(const struct bpf_verifier_log *log) +{ + return log->len_total >= 128 && log->len_total <= UINT_MAX >> 2 && + log->level && log->ubuf && !(log->level & ~BPF_LOG_MASK); +} + #define BPF_MAX_SUBPROGS 256 struct bpf_subprog_info { diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 79c0bcdcab842..b8ed4da63bc8c 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -4332,8 +4332,7 @@ static struct btf *btf_parse(bpfptr_t btf_data, u32 btf_data_size, log->len_total = log_size; /* log attributes have to be sane */ - if (log->len_total < 128 || log->len_total > UINT_MAX >> 2 || - !log->level || !log->ubuf) { + if (!bpf_verifier_log_attr_valid(log)) { err = -EINVAL; goto errout; } diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index b84e63d62b8af..18c75d6d98960 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -13759,11 +13759,11 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr) log->ubuf = (char __user *) (unsigned long) attr->log_buf; log->len_total = attr->log_size; - ret = -EINVAL; /* log attributes have to be sane */ - if (log->len_total < 128 || log->len_total > UINT_MAX >> 2 || - !log->level || !log->ubuf || log->level & ~BPF_LOG_MASK) + if (!bpf_verifier_log_attr_valid(log)) { + ret = -EINVAL; goto err_unlock; + } } if (IS_ERR(btf_vmlinux)) { -- 2.34.1