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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 39D18C2D0CE for ; Sun, 29 Dec 2019 17:32:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 03E6C207FD for ; Sun, 29 Dec 2019 17:32:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577640728; bh=b2lAYCsdQxVm++sV8rB0j0PrTWG0XRnBQ7ixlh3Ihrs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1KqXZYC6Sd+L/PzGhdvEZsHJm5/e23pSogcPc3ujy8jLDZKy+Wo85P3Rnr8fAFtGs 78cH9nC3mSH4/komjwKygIkkFSopNENG9cuYDNdVOMRKnudg7avzih/I5z9HNnNhFx urj4leem19tVSFvBlO5F2cxU0KN1fShh47rSf0AU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729258AbfL2RcH (ORCPT ); Sun, 29 Dec 2019 12:32:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:60112 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729234AbfL2RcB (ORCPT ); Sun, 29 Dec 2019 12:32:01 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C6E1A21D7E; Sun, 29 Dec 2019 17:32:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577640721; bh=b2lAYCsdQxVm++sV8rB0j0PrTWG0XRnBQ7ixlh3Ihrs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Jl7pYeCMzbDfZODgx4uHRlFOJZmHTKqfkRzubDsDP4Mb4p1yDPM+vcVVpMRIX49F7 PoX60Tgf6bGTmFMZElIDBhXjCUrIcxjbkZJpHd67AkW7jXRwtM+vkvUlQdActGpvot V7d4CygIo94gFSvt+VjbbdzU8UQLN+ovg+mY8bos= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= , Alexei Starovoitov , Andrii Nakryiko , Sasha Levin Subject: [PATCH 4.19 111/219] libbpf: Fix error handling in bpf_map__reuse_fd() Date: Sun, 29 Dec 2019 18:18:33 +0100 Message-Id: <20191229162525.365128942@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191229162508.458551679@linuxfoundation.org> References: <20191229162508.458551679@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Toke Høiland-Jørgensen [ Upstream commit d1b4574a4b86565325ef2e545eda8dfc9aa07c60 ] bpf_map__reuse_fd() was calling close() in the error path before returning an error value based on errno. However, close can change errno, so that can lead to potentially misleading error messages. Instead, explicitly store errno in the err variable before each goto. Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/157269297769.394725.12634985106772698611.stgit@toke.dk Signed-off-by: Sasha Levin --- tools/lib/bpf/libbpf.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index a62be78fc07b..249fa8d7376e 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1073,16 +1073,22 @@ int bpf_map__reuse_fd(struct bpf_map *map, int fd) return -errno; new_fd = open("/", O_RDONLY | O_CLOEXEC); - if (new_fd < 0) + if (new_fd < 0) { + err = -errno; goto err_free_new_name; + } new_fd = dup3(fd, new_fd, O_CLOEXEC); - if (new_fd < 0) + if (new_fd < 0) { + err = -errno; goto err_close_new_fd; + } err = zclose(map->fd); - if (err) + if (err) { + err = -errno; goto err_close_new_fd; + } free(map->name); map->fd = new_fd; @@ -1101,7 +1107,7 @@ err_close_new_fd: close(new_fd); err_free_new_name: free(new_name); - return -errno; + return err; } static int -- 2.20.1