From patchwork Mon Apr 12 08:39:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 419957 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=-18.8 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, 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 AFAB4C433B4 for ; Mon, 12 Apr 2021 09:06:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7EFB96135F for ; Mon, 12 Apr 2021 09:06:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237748AbhDLJGj (ORCPT ); Mon, 12 Apr 2021 05:06:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:56754 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239125AbhDLJEF (ORCPT ); Mon, 12 Apr 2021 05:04:05 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4F0E0611F0; Mon, 12 Apr 2021 09:01:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618218095; bh=rm9ZjEf/HQADCsU0jlY7B37iAmdTfwMuIlDGHZFKl1Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WzCTn7OQi4Ua2jRr1inYnAV2Rsmd2jXpruld5oppH3cnrdCzOEusQu+WkJI0Vn31D 0uJzTfc0PEtw6aKf3rr1UirIHTOTGgcN9Z0IKUAq6CSOFVtldd80PRFBH3hf6m33tD 4rD+ND3MhOrFin37a1fI/zQ9Z7+/CrDSATmwmSrc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= , Daniel Borkmann , Martin KaFai Lau Subject: [PATCH 5.11 052/210] bpf: Enforce that struct_ops programs be GPL-only Date: Mon, 12 Apr 2021 10:39:17 +0200 Message-Id: <20210412084017.735640517@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210412084016.009884719@linuxfoundation.org> References: <20210412084016.009884719@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Toke Høiland-Jørgensen commit 12aa8a9467b354ef893ce0fc5719a4de4949a9fb upstream. With the introduction of the struct_ops program type, it became possible to implement kernel functionality in BPF, making it viable to use BPF in place of a regular kernel module for these particular operations. Thus far, the only user of this mechanism is for implementing TCP congestion control algorithms. These are clearly marked as GPL-only when implemented as modules (as seen by the use of EXPORT_SYMBOL_GPL for tcp_register_congestion_control()), so it seems like an oversight that this was not carried over to BPF implementations. Since this is the only user of the struct_ops mechanism, just enforcing GPL-only for the struct_ops program type seems like the simplest way to fix this. Fixes: 0baf26b0fcd7 ("bpf: tcp: Support tcp_congestion_ops in bpf") Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Daniel Borkmann Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20210326100314.121853-1-toke@redhat.com Signed-off-by: Greg Kroah-Hartman --- kernel/bpf/verifier.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -11570,6 +11570,11 @@ static int check_struct_ops_btf_id(struc u32 btf_id, member_idx; const char *mname; + if (!prog->gpl_compatible) { + verbose(env, "struct ops programs must have a GPL compatible license\n"); + return -EINVAL; + } + btf_id = prog->aux->attach_btf_id; st_ops = bpf_struct_ops_find(btf_id); if (!st_ops) {