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 09706C4167E for ; Mon, 24 Jan 2022 21:34:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1454059AbiAXVbk (ORCPT ); Mon, 24 Jan 2022 16:31:40 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:38896 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1451331AbiAXVWl (ORCPT ); Mon, 24 Jan 2022 16:22:41 -0500 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 5222EB8123A; Mon, 24 Jan 2022 21:22:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 76659C340E5; Mon, 24 Jan 2022 21:22:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643059359; bh=9n98TaX+hUU8kjXcOlvMGtKM6jKo4501BytYLKGahLk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dhxDa85WKc3dpC+Iisml4rNXfOmm/n5kQtjixhHbQOLbODMl+0NPiJon4/IAdx/bh lGyYDy7iJ2R/iyPpvrwyN/PBoMDHfo8Ij8XScW/TUObtMdlfTPcLU7HAo+PqOASLta sRnanMXNquQIEk6c1FNHcbdPHkv5bV82XaQ1LP5Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrii Nakryiko , Alexei Starovoitov , Yonghong Song , Sasha Levin Subject: [PATCH 5.16 0546/1039] libbpf: Detect corrupted ELF symbols section Date: Mon, 24 Jan 2022 19:38:55 +0100 Message-Id: <20220124184143.626129823@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124184125.121143506@linuxfoundation.org> References: <20220124184125.121143506@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: stable@vger.kernel.org From: Andrii Nakryiko [ Upstream commit 833907876be55205d0ec153dcd819c014404ee16 ] Prevent divide-by-zero if ELF is corrupted and has zero sh_entsize. Reported by oss-fuzz project. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20211103173213.1376990-2-andrii@kernel.org Signed-off-by: Sasha Levin --- tools/lib/bpf/libbpf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 2696f0b7f0acc..1cc0383471f01 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -3556,7 +3556,7 @@ static int bpf_object__collect_externs(struct bpf_object *obj) scn = elf_sec_by_idx(obj, obj->efile.symbols_shndx); sh = elf_sec_hdr(obj, scn); - if (!sh) + if (!sh || sh->sh_entsize != sizeof(Elf64_Sym)) return -LIBBPF_ERRNO__FORMAT; dummy_var_btf_id = add_dummy_ksym_var(obj->btf); -- 2.34.1