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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6B53CC28CF2 for ; Mon, 15 Nov 2021 23:36:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 590EF61AFF for ; Mon, 15 Nov 2021 23:36:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355019AbhKOXiv (ORCPT ); Mon, 15 Nov 2021 18:38:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:44642 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343637AbhKOTVc (ORCPT ); Mon, 15 Nov 2021 14:21:32 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 469EE63361; Mon, 15 Nov 2021 18:43:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637001812; bh=Q5zjcowLXCgqtp8SfhHkbhKdn/gk/gQrke78Df4ajHM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cxAwFqlXzl6UIEpPHQ0EtjuPC+uHeNd5wtD+fT0VXk9bNNz3OL1L68wYZB6mrV7Ea Vy5iO3iUSmD/RyVymPL1g+xmmvkulTi93WBEBUK4MsoPxXE81OUZ7LJ0eXnOIeAZse jzlrMFammWjQ+xgIhJMTG8WG+7Oe629eXkWGE1Fg= 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?= , Andrii Nakryiko , Sasha Levin Subject: [PATCH 5.15 330/917] libbpf: Dont crash on object files with no symbol tables Date: Mon, 15 Nov 2021 17:57:05 +0100 Message-Id: <20211115165439.948895580@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165428.722074685@linuxfoundation.org> References: <20211115165428.722074685@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: Toke Høiland-Jørgensen [ Upstream commit 03e601f48b2da6fb44d0f7b86957a8f6bacfb347 ] If libbpf encounters an ELF file that has been stripped of its symbol table, it will crash in bpf_object__add_programs() when trying to dereference the obj->efile.symbols pointer. Fix this by erroring out of bpf_object__elf_collect() if it is not able able to find the symbol table. v2: - Move check into bpf_object__elf_collect() and add nice error message Fixes: 6245947c1b3c ("libbpf: Allow gaps in BPF program sections to support overriden weak functions") Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210901114812.204720-1-toke@redhat.com Signed-off-by: Sasha Levin --- tools/lib/bpf/libbpf.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index e4f83c304ec92..51180f300d2e1 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2993,6 +2993,12 @@ static int bpf_object__elf_collect(struct bpf_object *obj) } } + if (!obj->efile.symbols) { + pr_warn("elf: couldn't find symbol table in %s, stripped object file?\n", + obj->path); + return -ENOENT; + } + scn = NULL; while ((scn = elf_nextscn(elf, scn)) != NULL) { idx++; -- 2.33.0