From patchwork Wed Sep 1 12:27:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 505633 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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, 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 7613FC4320A for ; Wed, 1 Sep 2021 12:37:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 604DA611BD for ; Wed, 1 Sep 2021 12:37:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245744AbhIAMiC (ORCPT ); Wed, 1 Sep 2021 08:38:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:34838 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343676AbhIAMg1 (ORCPT ); Wed, 1 Sep 2021 08:36:27 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A6FA56113A; Wed, 1 Sep 2021 12:33:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1630499617; bh=mFocXmgVSL29Whb/Q4oIEBoQOT/3OAb0PeiOGH9bU4o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KT2KqdLHdZal4xj7hvL9RR9j/evgtWUlvls1olHaCn5/IY29r/QM8xJTjc3et29l5 1JOoCYaKOHHyR3eQ4ZUH8k2mxSt0uG+bgkjPTTR1tA+N0T7WZROKeaPxeNKJEm/qab 5S7LVzEImtcnNdqNDz69WBvcgK8wkKURuQeFDu5A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Borkmann , Alexei Starovoitov Subject: [PATCH 5.10 002/103] bpf: Fix ringbuf helper function compatibility Date: Wed, 1 Sep 2021 14:27:12 +0200 Message-Id: <20210901122300.585416501@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210901122300.503008474@linuxfoundation.org> References: <20210901122300.503008474@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Daniel Borkmann commit 5b029a32cfe4600f5e10e36b41778506b90fd4de upstream. Commit 457f44363a88 ("bpf: Implement BPF ring buffer and verifier support for it") extended check_map_func_compatibility() by enforcing map -> helper function match, but not helper -> map type match. Due to this all of the bpf_ringbuf_*() helper functions could be used with a wrong map type such as array or hash map, leading to invalid access due to type confusion. Also, both BPF_FUNC_ringbuf_{submit,discard} have ARG_PTR_TO_ALLOC_MEM as argument and not a BPF map. Therefore, their check_map_func_compatibility() presence is incorrect since it's only for map type checking. Fixes: 457f44363a88 ("bpf: Implement BPF ring buffer and verifier support for it") Reported-by: Ryota Shiga (Flatt Security) Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: Greg Kroah-Hartman --- kernel/bpf/verifier.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -4693,8 +4693,6 @@ static int check_map_func_compatibility( case BPF_MAP_TYPE_RINGBUF: if (func_id != BPF_FUNC_ringbuf_output && func_id != BPF_FUNC_ringbuf_reserve && - func_id != BPF_FUNC_ringbuf_submit && - func_id != BPF_FUNC_ringbuf_discard && func_id != BPF_FUNC_ringbuf_query) goto error; break; @@ -4798,6 +4796,12 @@ static int check_map_func_compatibility( if (map->map_type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) goto error; break; + case BPF_FUNC_ringbuf_output: + case BPF_FUNC_ringbuf_reserve: + case BPF_FUNC_ringbuf_query: + if (map->map_type != BPF_MAP_TYPE_RINGBUF) + goto error; + break; case BPF_FUNC_get_stackid: if (map->map_type != BPF_MAP_TYPE_STACK_TRACE) goto error;