From patchwork Thu Nov 7 01:46:40 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin KaFai Lau X-Patchwork-Id: 1190809 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.b="YTzA0lKN"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 477mTx4TQRz9sP3 for ; Thu, 7 Nov 2019 12:46:45 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728315AbfKGBqo (ORCPT ); Wed, 6 Nov 2019 20:46:44 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:45496 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727597AbfKGBqo (ORCPT ); Wed, 6 Nov 2019 20:46:44 -0500 Received: from pps.filterd (m0148460.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xA71iQRQ022250 for ; Wed, 6 Nov 2019 17:46:43 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=facebook; bh=vd+7RXw6TDZ1w+VTM6gFZdpZGF4UdxXMqvos2K/niFg=; b=YTzA0lKNorUfyRWkOxDhfKb1+/aOAfh4w0lo5ZwyYN6MYS2iMzMts/bjHkuwKo8JATwm kwtjmRCy7NYNkgrqXpE9aUO1BgL6qQaWBeaWP0sJ2h9t0DjjoxAHBiqadO3F5I60XzEa 3DbGNH4mmzgYn53N4aIpAFhHuPGLm4FkGaM= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 2w41u2jfhe-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 06 Nov 2019 17:46:43 -0800 Received: from 2401:db00:12:909f:face:0:3:0 (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::c) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Wed, 6 Nov 2019 17:46:42 -0800 Received: by devbig005.ftw2.facebook.com (Postfix, from userid 6611) id 0864429430DB; Wed, 6 Nov 2019 17:46:40 -0800 (PST) Smtp-Origin-Hostprefix: devbig From: Martin KaFai Lau Smtp-Origin-Hostname: devbig005.ftw2.facebook.com To: , CC: Alexei Starovoitov , Daniel Borkmann , David Miller , Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH v3 bpf-next 1/3] bpf: Account for insn->off when doing bpf_probe_read_kernel Date: Wed, 6 Nov 2019 17:46:40 -0800 Message-ID: <20191107014640.384083-1-kafai@fb.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191107014639.384014-1-kafai@fb.com> References: <20191107014639.384014-1-kafai@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95, 18.0.572 definitions=2019-11-06_09:2019-11-06, 2019-11-06 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 lowpriorityscore=0 bulkscore=0 suspectscore=8 priorityscore=1501 malwarescore=0 phishscore=0 adultscore=0 impostorscore=0 mlxlogscore=935 mlxscore=0 clxscore=1015 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1911070017 X-FB-Internal: deliver Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org In the bpf interpreter mode, bpf_probe_read_kernel is used to read from PTR_TO_BTF_ID's kernel object. It currently missed considering the insn->off. This patch fixes it. Fixes: 2a02759ef5f8 ("bpf: Add support for BTF pointers to interpreter") Signed-off-by: Martin KaFai Lau Acked-by: Andrii Nakryiko --- kernel/bpf/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 97e37d82a1cc..c1fde0303280 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1569,7 +1569,7 @@ static u64 __no_fgcse ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u6 #undef LDST #define LDX_PROBE(SIZEOP, SIZE) \ LDX_PROBE_MEM_##SIZEOP: \ - bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) SRC); \ + bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) (SRC + insn->off)); \ CONT; LDX_PROBE(B, 1) LDX_PROBE(H, 2)