From patchwork Thu Nov 12 00:19:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin KaFai Lau X-Patchwork-Id: 11898857 X-Patchwork-Delegate: bpf@iogearbox.net 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=-12.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 63251C56201 for ; Thu, 12 Nov 2020 01:51:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 06B782068E for ; Thu, 12 Nov 2020 01:51:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="i0GBKvzw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728298AbgKLBcJ (ORCPT ); Wed, 11 Nov 2020 20:32:09 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:10828 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728045AbgKLATZ (ORCPT ); Wed, 11 Nov 2020 19:19:25 -0500 Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.16.0.42/8.16.0.42) with SMTP id 0AC0HeeH012124 for ; Wed, 11 Nov 2020 16:19:23 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding : content-type; s=facebook; bh=Qs9jNaqAwvSALFjazs9WYcTGypE8uqVViyOuYjRO6go=; b=i0GBKvzwgrbp9XzpHHUL/BDNqmS6+ziIiHMARSDyzCcP40sbTK1E48D9L3m2M26nGtW+ KxNUSJDaHklRI+KmTHWZqOmHYl2lNvZwi0Mp6PRUpCFZKyJtPc3CaLLShtRxB99ENCKP fWLsgkP5JK/oae+wAKs/n+Ul5t7jPx00pA8= Received: from mail.thefacebook.com ([163.114.132.120]) by m0001303.ppops.net with ESMTP id 34r580f033-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 11 Nov 2020 16:19:23 -0800 Received: from intmgw002.08.frc2.facebook.com (2620:10d:c085:108::8) by mail.thefacebook.com (2620:10d:c085:11d::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Wed, 11 Nov 2020 16:19:21 -0800 Received: by devbig005.ftw2.facebook.com (Postfix, from userid 6611) id C666A2946698; Wed, 11 Nov 2020 16:19:19 -0800 (PST) From: Martin KaFai Lau To: CC: Alexei Starovoitov , Daniel Borkmann , , Roman Gushchin , KP Singh Subject: [PATCH bpf-next] bpf: Fix NULL dereference in bpf_task_storage Date: Wed, 11 Nov 2020 16:19:19 -0800 Message-ID: <20201112001919.2028357-1-kafai@fb.com> X-Mailer: git-send-email 2.24.1 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=2020-11-11_12:2020-11-10,2020-11-11 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 suspectscore=13 spamscore=0 mlxlogscore=761 malwarescore=0 phishscore=0 adultscore=0 lowpriorityscore=0 priorityscore=1501 bulkscore=0 mlxscore=0 impostorscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011120000 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net In bpf_pid_task_storage_update_elem(), it missed to test the !task_storage_ptr(task) which then could trigger a NULL pointer exception in bpf_local_storage_update(). Fixes: 4cf1bc1f1045 ("bpf: Implement task local storage") Tested-by: Roman Gushchin Cc: KP Singh Signed-off-by: Martin KaFai Lau --- kernel/bpf/bpf_task_storage.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/bpf_task_storage.c b/kernel/bpf/bpf_task_storage.c index 39a45fba4fb0..4ef1959a78f2 100644 --- a/kernel/bpf/bpf_task_storage.c +++ b/kernel/bpf/bpf_task_storage.c @@ -150,7 +150,7 @@ static int bpf_pid_task_storage_update_elem(struct bpf_map *map, void *key, */ WARN_ON_ONCE(!rcu_read_lock_held()); task = pid_task(pid, PIDTYPE_PID); - if (!task) { + if (!task || !task_storage_ptr(task)) { err = -ENOENT; goto out; }