From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:49190 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727947AbeJQBFk (ORCPT ); Tue, 16 Oct 2018 21:05:40 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Vyukov , Martin KaFai Lau , Yonghong Song , Daniel Borkmann , Sasha Levin Subject: [PATCH 4.18 091/135] bpf: btf: Fix end boundary calculation for type section Date: Tue, 16 Oct 2018 19:05:21 +0200 Message-Id: <20181016170521.639981592@linuxfoundation.org> In-Reply-To: <20181016170515.447235311@linuxfoundation.org> References: <20181016170515.447235311@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Martin KaFai Lau [ Upstream commit 4b1c5d917d34f705096bb7dd8a2bd19b0881970e ] The end boundary math for type section is incorrect in btf_check_all_metas(). It just happens that hdr->type_off is always 0 for now because there are only two sections (type and string) and string section must be at the end (ensured in btf_parse_str_sec). However, type_off may not be 0 if a new section would be added later. This patch fixes it. Fixes: f80442a4cd18 ("bpf: btf: Change how section is supported in btf_header") Reported-by: Dmitry Vyukov Signed-off-by: Martin KaFai Lau Acked-by: Yonghong Song Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- kernel/bpf/btf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -1844,7 +1844,7 @@ static int btf_check_all_metas(struct bt hdr = &btf->hdr; cur = btf->nohdr_data + hdr->type_off; - end = btf->nohdr_data + hdr->type_len; + end = cur + hdr->type_len; env->log_type_id = 1; while (cur < end) {