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,URIBL_BLOCKED,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 0B49BC07533 for ; Sun, 8 Sep 2019 12:50:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D9FC021920 for ; Sun, 8 Sep 2019 12:49:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567946999; bh=XnMCGqNX4fqjv1YWON+5G92IJbWmNbmH9o/BmbQb2Vc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mZydDsu5muasqTABURBKQt/mPylHghyrPPM4QwmLMkcsUqjrJrXtAqJoAl3qAHij1 F6fLE7jcGaS/DFOKwZHf+KGWUQLUgwZzMQBsTyjkRejQaqQLrmHzt6dKXZaq1anjFE zaWRcfBqoRHx5LpTQy/MZfYC8GZpXMyl37AoAdtA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731879AbfIHMt6 (ORCPT ); Sun, 8 Sep 2019 08:49:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:40308 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731838AbfIHMt4 (ORCPT ); Sun, 8 Sep 2019 08:49:56 -0400 Received: from localhost (unknown [62.28.240.114]) (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 684AE218AF; Sun, 8 Sep 2019 12:49:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567946995; bh=XnMCGqNX4fqjv1YWON+5G92IJbWmNbmH9o/BmbQb2Vc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QPU78k6zNS2RhRSdqnTRFqLSvO4bJsJe+vOZgXmEhIH/+SRulL+ug5priE2Z0XdQr 0Iruy8NhOJqYtKV8U3m7SgBLKAbW6hNc+ToFuH2OGDVZlv/Sv7Tb3LxjHBcwGPfOcv 1XkCY2dSb6uYUPCkChJ4ElJ0YRIeLa9ItTmiZ2uA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrey Ignatov , Andrii Nakryiko , Alexei Starovoitov , Sasha Levin Subject: [PATCH 5.2 22/94] libbpf: set BTF FD for prog only when there is supported .BTF.ext data Date: Sun, 8 Sep 2019 13:41:18 +0100 Message-Id: <20190908121151.074226634@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190908121150.420989666@linuxfoundation.org> References: <20190908121150.420989666@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 [ Upstream commit 3415ec643e7bd644b03026efbe2f2b36cbe9b34b ] 5d01ab7bac46 ("libbpf: fix erroneous multi-closing of BTF FD") introduced backwards-compatibility issue, manifesting itself as -E2BIG error returned on program load due to unknown non-zero btf_fd attribute value for BPF_PROG_LOAD sys_bpf() sub-command. This patch fixes bug by ensuring that we only ever associate BTF FD with program if there is a BTF.ext data that was successfully loaded into kernel, which automatically means kernel supports func_info/line_info and associated BTF FD for progs (checked and ensured also by BTF sanitization code). Fixes: 5d01ab7bac46 ("libbpf: fix erroneous multi-closing of BTF FD") Reported-by: Andrey Ignatov Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- tools/lib/bpf/libbpf.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 21355f6be2434..0ccf6aa533ae9 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2071,7 +2071,11 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, load_attr.license = license; load_attr.kern_version = kern_version; load_attr.prog_ifindex = prog->prog_ifindex; - btf_fd = bpf_object__btf_fd(prog->obj); + /* if .BTF.ext was loaded, kernel supports associated BTF for prog */ + if (prog->obj->btf_ext) + btf_fd = bpf_object__btf_fd(prog->obj); + else + btf_fd = -1; load_attr.prog_btf_fd = btf_fd >= 0 ? btf_fd : 0; load_attr.func_info = prog->func_info; load_attr.func_info_rec_size = prog->func_info_rec_size; -- 2.20.1