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 12B91C433EF for ; Tue, 18 Jan 2022 03:08:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344685AbiARDIM (ORCPT ); Mon, 17 Jan 2022 22:08:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35982 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240359AbiARC46 (ORCPT ); Mon, 17 Jan 2022 21:56:58 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D1276C0613AD; Mon, 17 Jan 2022 18:44:40 -0800 (PST) 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 88980B8125F; Tue, 18 Jan 2022 02:44:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79901C36AEB; Tue, 18 Jan 2022 02:44:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642473878; bh=heTk60CDtiDxyRuaYkCe/Cwdp8eX4YXc3TH7vtDBWIo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pKyk3GF2avIvEl8R6l8e9ybJWkMHCnHfPQMfka9Upq/MdvrmcSlMAz9x8CvQ/wze1 4kvm1skQzs3qZpRJhOJ639KVFFclUXfCzK3JyNZUMSkKSwZ6SvyvhUKNcKWTv9MxDV /wHmfVeMMUWkPCn02yqrl/QPwASdkqNg8qBD8v0b/ri9BrnE5y+zmchr70pYLE1l1d HoxyTMT5VuPj4kgFEYm5E0Aj9oO1se7Yx7sZyML+TDnfF9/Pp+kcssYUWCgBDZe0XC g30zlXhQKmCapIHqC5hMcljmd5rTrWMgcedwhjhinXXcoUb2EtfhOh0ca5Yhxvu0aq +kPbMVi6pMS+Q== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Andrii Nakryiko , Alexei Starovoitov , Yonghong Song , Sasha Levin , daniel@iogearbox.net, netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 03/73] libbpf: Validate that .BTF and .BTF.ext sections contain data Date: Mon, 17 Jan 2022 21:43:22 -0500 Message-Id: <20220118024432.1952028-3-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118024432.1952028-1-sashal@kernel.org> References: <20220118024432.1952028-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Andrii Nakryiko [ Upstream commit 62554d52e71797eefa3fc15b54008038837bb2d4 ] .BTF and .BTF.ext ELF sections should have SHT_PROGBITS type and contain data. If they are not, ELF is invalid or corrupted, so bail out. Otherwise this can lead to data->d_buf being NULL and SIGSEGV later on. 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/20211103173213.1376990-4-andrii@kernel.org Signed-off-by: Sasha Levin --- tools/lib/bpf/libbpf.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 2a1dbf52fc9a5..54e776886bf1e 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1578,8 +1578,12 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags) } else if (strcmp(name, MAPS_ELF_SEC) == 0) { obj->efile.btf_maps_shndx = idx; } else if (strcmp(name, BTF_ELF_SEC) == 0) { + if (sh->sh_type != SHT_PROGBITS) + return -LIBBPF_ERRNO__FORMAT; btf_data = data; } else if (strcmp(name, BTF_EXT_ELF_SEC) == 0) { + if (sh->sh_type != SHT_PROGBITS) + return -LIBBPF_ERRNO__FORMAT; btf_ext_data = data; } else if (sh.sh_type == SHT_SYMTAB) { if (obj->efile.symbols) { -- 2.34.1