From patchwork Thu Nov 19 23:22:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 1403361 Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CcbMR1nbfz9sVT for ; Fri, 20 Nov 2020 10:23:15 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726498AbgKSXXC convert rfc822-to-8bit (ORCPT ); Thu, 19 Nov 2020 18:23:02 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:23634 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726474AbgKSXXC (ORCPT ); Thu, 19 Nov 2020 18:23:02 -0500 Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0AJNKgIZ027851 for ; Thu, 19 Nov 2020 15:23:01 -0800 Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 34wgckr7mx-5 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 19 Nov 2020 15:23:01 -0800 Received: from intmgw003.03.ash8.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Thu, 19 Nov 2020 15:22:51 -0800 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id DAE722EC9B9C; Thu, 19 Nov 2020 15:22:47 -0800 (PST) From: Andrii Nakryiko To: , , , CC: , Subject: [PATCH bpf-next 1/6] bpf: fix bpf_put_raw_tracepoint()'s use of __module_address() Date: Thu, 19 Nov 2020 15:22:39 -0800 Message-ID: <20201119232244.2776720-2-andrii@kernel.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20201119232244.2776720-1-andrii@kernel.org> References: <20201119232244.2776720-1-andrii@kernel.org> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.312,18.0.737 definitions=2020-11-19_14:2020-11-19,2020-11-19 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 malwarescore=0 mlxscore=0 suspectscore=8 clxscore=1015 adultscore=0 spamscore=0 impostorscore=0 lowpriorityscore=0 bulkscore=0 priorityscore=1501 mlxlogscore=825 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011190160 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org __module_address() needs to be called with preemption disabled or with module_mutex taken. preempt_disable() is enough for read-only uses, which is what this fix does. Fixes: a38d1107f937 ("bpf: support raw tracepoints in modules") Signed-off-by: Andrii Nakryiko Acked-by: Martin KaFai Lau --- kernel/trace/bpf_trace.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index d255bc9b2bfa..bb98a377050a 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2060,7 +2060,11 @@ struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name) void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp) { - struct module *mod = __module_address((unsigned long)btp); + struct module *mod; + + preempt_disable(); + mod = __module_address((unsigned long)btp); + preempt_enable(); if (mod) module_put(mod);