From patchwork Fri Jun 23 14:15:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 13290710 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 4425FEB64DD for ; Fri, 23 Jun 2023 14:16:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231715AbjFWOQ3 (ORCPT ); Fri, 23 Jun 2023 10:16:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48866 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229564AbjFWOQ2 (ORCPT ); Fri, 23 Jun 2023 10:16:28 -0400 Received: from mail-oa1-x2e.google.com (mail-oa1-x2e.google.com [IPv6:2001:4860:4864:20::2e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B161C1BDF; Fri, 23 Jun 2023 07:16:27 -0700 (PDT) Received: by mail-oa1-x2e.google.com with SMTP id 586e51a60fabf-1acfce1fc0bso544507fac.2; Fri, 23 Jun 2023 07:16:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1687529787; x=1690121787; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=VR64Cmt8i5FJsJGupQTPYJtgTllYuN+cFKijdvjcj5o=; b=EQ7iNkE7ti0f7zBc5e//BENDi552fhrE7IpR9u5FeBTGZdzSKCVDhsvM2Aa77gqDcw sHKdRyqJcO2vIufs5qlCx7uo6hwODOzuWkI689nmevebIK2EB1ezWJ3brS8bEjJ23am4 NibywcXiPYFOMaqeMb9/oJo889m0lADlR6hkV67HhHPk6LWx0CJvDmHgyB85yZN5Uxg6 1D9RPnzxN+LVS20sHas8jQ7F7nu+b29jTqE45Dj3z/+Ta2PCoRGzx1FkjQVeH4Bq9Pk8 Kop+RjrkxNBSp6X1gt/dU1041lqsn+Wb42D8ROdytdWsycyXSfXv9ZhRbFzrkeoeHYef zgwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687529787; x=1690121787; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=VR64Cmt8i5FJsJGupQTPYJtgTllYuN+cFKijdvjcj5o=; b=CmXotASDEYeYgS5EPiFmHMj6kMUh5ckTDZcpxZ9o3XfvBwqvFuJaSa4WANxfJUq7Gn 57lrQwYLx0B7if9VpMXOSCSgvEJfaPl5cH9c/dFn9uZbc10QcoQ7RWzYpXgvEQJWjJmp ogg6mKWjDHRmvInvcwXpSOCHkRdlv5En0YY5OEYfQxWKp974xc9HZIQzf26+VsN6mf63 ubSsUqBWLfrCVDUhSGuRWXa7XXHwdwVRpX51s+wHEApFWE7uuYvU4KUCoSaMr3dcOp7c hwxtHQhQccjDkb1fLAMdwIzeLsVKJevnT/M8IjWwJX1mEXCIymxqQx0M2UiEW6DklMP9 YBvg== X-Gm-Message-State: AC+VfDwrPc1wIjDfp9LjKP7aiS7i9ql6spsDujNmOwh4mx2ne6qEuJKf m3ypAS1brWp5GKW/fImbWNE= X-Google-Smtp-Source: ACHHUZ42HZuuQHS2WbQ0zQXjoMb8L5bxZPsRe8wyzSeG/Hj0exEthhJb++8LC4+zFak4KVBYeS12DA== X-Received: by 2002:a05:6870:c805:b0:1a6:c04a:84ef with SMTP id ee5-20020a056870c80500b001a6c04a84efmr10844401oab.6.1687529786912; Fri, 23 Jun 2023 07:16:26 -0700 (PDT) Received: from vultr.guest ([2001:19f0:ac01:1058:5400:4ff:fe7c:972]) by smtp.gmail.com with ESMTPSA id p14-20020a63e64e000000b005533c53f550sm6505942pgj.45.2023.06.23.07.16.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 23 Jun 2023 07:16:26 -0700 (PDT) From: Yafang Shao To: ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@fb.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, quentin@isovalent.com, rostedt@goodmis.org, mhiramat@kernel.org Cc: bpf@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Yafang Shao Subject: [PATCH v5 bpf-next 07/11] bpf: Add a common helper bpf_copy_to_user() Date: Fri, 23 Jun 2023 14:15:42 +0000 Message-Id: <20230623141546.3751-8-laoar.shao@gmail.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20230623141546.3751-1-laoar.shao@gmail.com> References: <20230623141546.3751-1-laoar.shao@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org Add a common helper bpf_copy_to_user(), which will be used at multiple places. No functional change. Signed-off-by: Yafang Shao --- kernel/bpf/syscall.c | 34 ++++++++++++++++++++-------------- 1 file changed, 20 insertions(+), 14 deletions(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index a75c54b..f3e2d4e 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3291,6 +3291,25 @@ static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link, raw_tp_link->btp->tp->name); } +static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen, + u32 len) +{ + if (ulen >= len + 1) { + if (copy_to_user(ubuf, buf, len + 1)) + return -EFAULT; + } else { + char zero = '\0'; + + if (copy_to_user(ubuf, buf, ulen - 1)) + return -EFAULT; + if (put_user(zero, ubuf + ulen - 1)) + return -EFAULT; + return -ENOSPC; + } + + return 0; +} + static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, struct bpf_link_info *info) { @@ -3309,20 +3328,7 @@ static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link, if (!ubuf) return 0; - if (ulen >= tp_len + 1) { - if (copy_to_user(ubuf, tp_name, tp_len + 1)) - return -EFAULT; - } else { - char zero = '\0'; - - if (copy_to_user(ubuf, tp_name, ulen - 1)) - return -EFAULT; - if (put_user(zero, ubuf + ulen - 1)) - return -EFAULT; - return -ENOSPC; - } - - return 0; + return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len); } static const struct bpf_link_ops bpf_raw_tp_link_lops = {