From patchwork Tue Oct 3 08:38:35 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hengqi Chen X-Patchwork-Id: 147760 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:612c:2a8e:b0:403:3b70:6f57 with SMTP id in14csp1942146vqb; Tue, 3 Oct 2023 01:44:33 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEpa2jJ6jEQB/XbVqYISIujiu6jp0m6rBDuu4gamXilUxn+EbdmW8J1QW+Y7jYH4r1Errzn X-Received: by 2002:a05:6870:4712:b0:1d6:567c:deb4 with SMTP id b18-20020a056870471200b001d6567cdeb4mr17220145oaq.42.1696322673210; Tue, 03 Oct 2023 01:44:33 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1696322673; cv=none; d=google.com; s=arc-20160816; b=q0vgXTJVtMLgH6WwzbwLQ//N6MltKQoRAWJ2rbU8yRhlwWpQVXjFb7/nVRjQwGQtUY UgyO1+Kao67YZTTW/yZJcc2y1IoF7NgNlsGX+6nv8K9ePFf2LlC+aXbfoiT40EPTLca+ 8sF8qRDumSyUACdT96TRxzoyNs5FDZeMzIovRkKFL6tBL+CYtUGw30jixriIQybbn5/Y GTZRo+UcEu+clElSvVfyhiBoTsr8eNeydhQMNJFFVAJH4hy7bLRvoHSv0RjwopOj7nsj O94QISIeEq1Dka1LKw968lmlI+msGlEMqVk2UqlvwezO8m2BmCmmZgZYz3oTgQcrxlTG xZ3Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=H9i4lTlGpn05Zib6O3CFGJDGsZ1WXq3wp2jJyI4hXGQ=; fh=DRFGKMrXi0yLz3nURRYjQq65yfvW5/0oGnrPIKoecFQ=; b=aufF067uO9rQW1K6o6SzqmYoSYMgsBB/5pbd7qTNgOXo+UzJ4+NfNjQxsPha4YpT1v sJqioH9PtENYz4R/fQLacReggpz5MBID9PvuhpTYefGB2cfgtgGA9EniNtVvp5BBE0Dz pmJ9xqES/fVMxymc0/EnnwUTf+i9XrMsONW6EcKlJ8YEBZz/FDHwu/nMeh1RBNMDRGNx xUqRVlR8zetfWZvdT+8SjRmMoxZBxBNKZwzbdla2tN1BLwmj2xTJkYH5BSVpCHVRaxpU 5FT+0sTMcOEtO0Bj3DIWLM6guu/fLwLFRjeBHmao1IupXtFflMRwpBP3dIVezRePHRZr Di+w== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=ItklvqAO; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from snail.vger.email (snail.vger.email. [2620:137:e000::3:7]) by mx.google.com with ESMTPS id e19-20020a656493000000b00578e5228c76si906162pgv.505.2023.10.03.01.44.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Oct 2023 01:44:33 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=ItklvqAO; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 9460E813CDAE; Tue, 3 Oct 2023 01:44:32 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231247AbjJCIoa (ORCPT + 18 others); Tue, 3 Oct 2023 04:44:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43142 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231223AbjJCIo2 (ORCPT ); Tue, 3 Oct 2023 04:44:28 -0400 Received: from mail-pl1-x635.google.com (mail-pl1-x635.google.com [IPv6:2607:f8b0:4864:20::635]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C046FAD; Tue, 3 Oct 2023 01:44:23 -0700 (PDT) Received: by mail-pl1-x635.google.com with SMTP id d9443c01a7336-1c724577e1fso4927895ad.0; Tue, 03 Oct 2023 01:44:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1696322663; x=1696927463; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=H9i4lTlGpn05Zib6O3CFGJDGsZ1WXq3wp2jJyI4hXGQ=; b=ItklvqAOlbJyF2yYnQ4uGMLpl9Mb5wguTz5ECBBDTQ26hfJbbA6Uvq9SGgM89T71CU 1pMfhdLscLouaAuPyDHiG59hR0cxsz82isV8WuXUZXbu2nv2tGXLsodPh4TkZ4K5iU9m q+Hrp0b6EWWwjzRz29cihBReZpruwRNIXMdGGuAPuRhIjZn+CKZ43VhpDUiB0vVq7yng ZY+fCZnoURNUQD6f8LhTCkmYgKv9PdzGMp0CtlkpPTCesE5ZBhnYaNaHgbUtFu+olUtz CST1YKl8PLRh32KYaL2wT+mSSlMmCY0mjPxB0lylWvNu1JAEQ6b0nNxvQVLviRMT2ncj T8Qg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696322663; x=1696927463; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=H9i4lTlGpn05Zib6O3CFGJDGsZ1WXq3wp2jJyI4hXGQ=; b=XO9aNCV9lGUfFYN8Jcn1sp3KHmxDnaaSxypFpOpHS9/n8UfHor6MVtUMa4RNx8IClS ujnX1CwFGJEnQ0tuJyT8cw65hSN6RtbeL8sB8huECsSPqPo7OQIEisuEpzVcSNd45b6C rOd37GV1dnBujMtXRL14r2y/sFoLPHQ09Ev0jKa3k8+e2YI+Z3VgaEPvnXrjNvcUz3xC 44Fr/VbxP89wuxlpsBNcelwjEUOw1OMnXDjKUtsVfr9zJJyuLaL7ibtLVTo6kqATv3yS qBdfWj/TF60Uo/Ex/QArifnggrkAaRTpcY2CdxmRG7UOXel48g/EvEqmXC9s2P/Pu8Vw meVA== X-Gm-Message-State: AOJu0Yz9sxTzPUdH6hxB/HhJGc75bap7iGzvqbZTrtUSc9nvF5AoOGsc MVtPKo/QqnJd77yYQux8cClVUrDf49e3eV+o X-Received: by 2002:a17:903:2348:b0:1c7:2661:91e1 with SMTP id c8-20020a170903234800b001c7266191e1mr16827636plh.15.1696322662929; Tue, 03 Oct 2023 01:44:22 -0700 (PDT) Received: from ubuntu.. ([113.64.184.44]) by smtp.googlemail.com with ESMTPSA id y16-20020a17090322d000b001bc445e249asm902876plg.124.2023.10.03.01.44.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Oct 2023 01:44:22 -0700 (PDT) From: Hengqi Chen To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org Cc: keescook@chromium.org, luto@amacapital.net, wad@chromium.org, alexyonghe@tencent.com, hengqi.chen@gmail.com Subject: [RFC PATCH 1/2] seccomp: Introduce SECCOMP_LOAD_FILTER operation Date: Tue, 3 Oct 2023 08:38:35 +0000 Message-Id: <20231003083836.100706-2-hengqi.chen@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003083836.100706-1-hengqi.chen@gmail.com> References: <20231003083836.100706-1-hengqi.chen@gmail.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Tue, 03 Oct 2023 01:44:32 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1778723243375975705 X-GMAIL-MSGID: 1778723243375975705 This patch adds a new operation named SECCOMP_LOAD_FILTER. It accepts the same arguments as SECCOMP_SET_MODE_FILTER but only performs the loading process. If succeed, return a new fd associated with the JITed BPF program (the filter). The filter can then be pinned to bpffs using the returned fd and reused for different processes. Signed-off-by: Hengqi Chen --- include/uapi/linux/seccomp.h | 1 + kernel/seccomp.c | 64 ++++++++++++++++++++++++++++++++++++ 2 files changed, 65 insertions(+) diff --git a/include/uapi/linux/seccomp.h b/include/uapi/linux/seccomp.h index dbfc9b37fcae..ee2c83697810 100644 --- a/include/uapi/linux/seccomp.h +++ b/include/uapi/linux/seccomp.h @@ -16,6 +16,7 @@ #define SECCOMP_SET_MODE_FILTER 1 #define SECCOMP_GET_ACTION_AVAIL 2 #define SECCOMP_GET_NOTIF_SIZES 3 +#define SECCOMP_LOAD_FILTER 4 /* Valid flags for SECCOMP_SET_MODE_FILTER */ #define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0) diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 255999ba9190..7aff22f56a91 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -1996,12 +1996,71 @@ static long seccomp_set_mode_filter(unsigned int flags, seccomp_filter_free(prepared); return ret; } + +static long seccomp_load_filter(const char __user *filter) +{ + struct sock_fprog fprog; + struct bpf_prog *prog; + int ret = -EFAULT; + const bool save_orig = +#if defined(CONFIG_CHECKPOINT_RESTORE) || defined(SECCOMP_ARCH_NATIVE) + true; +#else + false; +#endif + +#ifdef CONFIG_COMPAT + if (in_compat_syscall()) { + struct compat_sock_fprog fprog32; + if (copy_from_user(&fprog32, filter, sizeof(fprog32))) + goto out; + fprog.len = fprog32.len; + fprog.filter = compat_ptr(fprog32.filter); + } else /* falls through to the if below. */ +#endif + if (copy_from_user(&fprog, filter, sizeof(fprog))) + goto out; + + ret = -EINVAL; + if (fprog.len == 0 || fprog.len > BPF_MAXINSNS) + goto out; + + BUG_ON(INT_MAX / fprog.len < sizeof(struct sock_filter)); + + ret = bpf_prog_create_from_user(&prog, &fprog, seccomp_check_filter, save_orig); + if (ret < 0) + goto out; + + ret = security_bpf_prog_alloc(prog->aux); + if (ret) { + ret = -EINVAL; + goto prog_free; + } + + prog->aux->user = get_current_user(); + atomic64_set(&prog->aux->refcnt, 1); + + ret = bpf_prog_new_fd(prog); + if (ret < 0) + bpf_prog_put(prog); + return ret; + +prog_free: + bpf_prog_free(prog); +out: + return ret; +} #else static inline long seccomp_set_mode_filter(unsigned int flags, const char __user *filter) { return -EINVAL; } + +static inline long seccomp_load_filter(const char __user *filter) +{ + return -EINVAL; +} #endif static long seccomp_get_action_avail(const char __user *uaction) @@ -2063,6 +2122,11 @@ static long do_seccomp(unsigned int op, unsigned int flags, return -EINVAL; return seccomp_get_notif_sizes(uargs); + case SECCOMP_LOAD_FILTER: + if (flags != 0) + return -EINVAL; + + return seccomp_load_filter(uargs); default: return -EINVAL; } From patchwork Tue Oct 3 08:38:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hengqi Chen X-Patchwork-Id: 147761 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:612c:2a8e:b0:403:3b70:6f57 with SMTP id in14csp1942190vqb; Tue, 3 Oct 2023 01:44:40 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGwhoH+7tPgpoBSwO5qHj13FI50C8sLJCr34V2Q0kvxNl9fL6Fo+AFx4qU2YEv+roh9GGe6 X-Received: by 2002:a17:902:e549:b0:1c3:d07f:39f7 with SMTP id n9-20020a170902e54900b001c3d07f39f7mr14803131plf.62.1696322679879; Tue, 03 Oct 2023 01:44:39 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1696322679; cv=none; d=google.com; s=arc-20160816; b=xDxW4CzNzUHsbpof4JVeAvauC04KmqSeN6+M1z4jkJxSXhwIBdPp7tfXUWbV/4jtA1 b0x7KUmOPODQw4fJ84xAU/8hQaPqzrPtYXufwQcn8HViZjkWrxe6ZrAt7N6ZN0AMZyhP K7RAeRgLsttiG+Kg8lU+9jtID8qx1J6rpf0Fnk8KkT3nyGvCRifADFe3L3NeKz1plrWD T/VewJsJXwzNqKmGfMo3h11Su1Af//I+mq+seeXSc7etyQbtvK4rPRcNfnMlkVVZ7hnn AXYpgxHLOAdJTEznZi4Z477B/3xp5cwnWayh4VOwjmeDWI6KJtHzPDUl1IGAZQkH0dxB yYgg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=forSh8N1C+dIxQ58h4NORFcN5/NjK9xQ8ABzqSG+rNM=; fh=DRFGKMrXi0yLz3nURRYjQq65yfvW5/0oGnrPIKoecFQ=; b=HBjrKZsaO7XVkq0HfXxnDKiYjGPIBKImE2i+ykA+8egIHx0KYW/tkr4+9h1mUTGt1l tn2tSy1hry4GOZ0HVM6/76eXtCBMqICUgqoKPlFhQujjssBVQWRS3gkVP1Tlxa9evDSo 6/0R27QsEFj0ekGE+2SmpdRcFtGJJGg71Ontc3jtihAnd3uWOXre93wLMmPL9ZMgYS0q 9M6lziBvxGi3tVzjC1iKYfaWzYBShhvEs+HwJPx30Fm7qZEzBdvucDoT6T4ju5hVm9UQ UApSZiRTWw6oU/nnFKH4Bf9huHaTEw4cbX2jyN3t65OgViaX5t+58CIvpI+EwOacigDi HsXg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=NJAGUNoV; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from snail.vger.email (snail.vger.email. [2620:137:e000::3:7]) by mx.google.com with ESMTPS id t9-20020a17090340c900b001ab29e00303si953923pld.426.2023.10.03.01.44.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Oct 2023 01:44:39 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=NJAGUNoV; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id B7F7F814E347; Tue, 3 Oct 2023 01:44:38 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239330AbjJCIoh (ORCPT + 18 others); Tue, 3 Oct 2023 04:44:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43252 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231241AbjJCIog (ORCPT ); Tue, 3 Oct 2023 04:44:36 -0400 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7CC78BD; Tue, 3 Oct 2023 01:44:31 -0700 (PDT) Received: by mail-pl1-x62f.google.com with SMTP id d9443c01a7336-1c3d8fb23d9so4974435ad.0; Tue, 03 Oct 2023 01:44:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1696322671; x=1696927471; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=forSh8N1C+dIxQ58h4NORFcN5/NjK9xQ8ABzqSG+rNM=; b=NJAGUNoVcJNaeAwDna4NgzMGoWB3GrKUg+O5PWYUQubi9uW/VjX4RmQpC1yduKfCbU YTQ0MPTCETnKanfKsdMApaxow1SNbvwRDGwJmzr7OkFHoavrcndMAhA8bgBnVlXQ33qj 8I1wIXC/MqB2nKDqPh3Afb7jyLx4rmBd5fCmZnn6+ed1vVoVXYCGWD7tlUlGUvhxZ6hr leelOHUMH8bGJX386eQVJq36Yzm8UdNCxsePEPf/FkCEVsf7uTUdbx8aUaEUI07wzjEr jOe8hTtxtNhwOy6mVS1LESZytcyRDtXmc20T6ktMOQq6IP2LFKMYJvbr6oBNoTMmXin0 El1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696322671; x=1696927471; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=forSh8N1C+dIxQ58h4NORFcN5/NjK9xQ8ABzqSG+rNM=; b=tcPZUtEJG/EH8YRhMrnbn8QzF/qddqK9RogBxo46EYUFYBba4/g6RwKWpfgK7/ge+Z m14eIRaxdla3Ch5lA2B1NANhxNtpb3f8GNpkQAWQrMV+u+sk4lfkUARjNEHNkfVc+TRI 0kKeuu9ShW2q2Fbcr/bI45TqWMfCmVEmasDMHW8m23Bt6OD4MZy1eddYhCVNtMYgEdgk AHEffwTcTzxNzAuvQ/VDMiea2jN0iyRNHucKizG6afNt/zYCFnZ1i1jGTBlY2A6aF6gN 82YxuKBEZV1j0NtWdj4EcmKHU1nsH/G2J1SOTHQrk4XM1MjxYlFLSkDqThxCAksQ9z67 wX8w== X-Gm-Message-State: AOJu0YzB/8A3GGq2VSGA/iBBsxYKSVedChOcqQw0Q/UC0QSxYypyRVB1 dO3O+Ly28I+CEk1ObdDKcs06jScHfLJus87J X-Received: by 2002:a17:902:ea0c:b0:1c6:3157:29f3 with SMTP id s12-20020a170902ea0c00b001c6315729f3mr12748250plg.36.1696322670713; Tue, 03 Oct 2023 01:44:30 -0700 (PDT) Received: from ubuntu.. ([113.64.184.44]) by smtp.googlemail.com with ESMTPSA id y16-20020a17090322d000b001bc445e249asm902876plg.124.2023.10.03.01.44.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Oct 2023 01:44:30 -0700 (PDT) From: Hengqi Chen To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org Cc: keescook@chromium.org, luto@amacapital.net, wad@chromium.org, alexyonghe@tencent.com, hengqi.chen@gmail.com Subject: [RFC PATCH 2/2] seccomp: Introduce SECCOMP_ATTACH_FILTER operation Date: Tue, 3 Oct 2023 08:38:36 +0000 Message-Id: <20231003083836.100706-3-hengqi.chen@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003083836.100706-1-hengqi.chen@gmail.com> References: <20231003083836.100706-1-hengqi.chen@gmail.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Tue, 03 Oct 2023 01:44:38 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1778723250631670788 X-GMAIL-MSGID: 1778723250631670788 The SECCOMP_ATTACH_FILTER operation is used to attach a loaded filter to the current process. The loaded filter is represented by a fd which is either returned by the SECCOMP_LOAD_FILTER operation or obtained from bpffs using bpf syscall. Signed-off-by: Hengqi Chen --- include/uapi/linux/seccomp.h | 1 + kernel/seccomp.c | 74 ++++++++++++++++++++++++++++++++++-- 2 files changed, 71 insertions(+), 4 deletions(-) diff --git a/include/uapi/linux/seccomp.h b/include/uapi/linux/seccomp.h index ee2c83697810..fbe30262fdfc 100644 --- a/include/uapi/linux/seccomp.h +++ b/include/uapi/linux/seccomp.h @@ -17,6 +17,7 @@ #define SECCOMP_GET_ACTION_AVAIL 2 #define SECCOMP_GET_NOTIF_SIZES 3 #define SECCOMP_LOAD_FILTER 4 +#define SECCOMP_ATTACH_FILTER 5 /* Valid flags for SECCOMP_SET_MODE_FILTER */ #define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0) diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 7aff22f56a91..adfafee4c3da 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -862,7 +862,7 @@ static void seccomp_cache_prepare(struct seccomp_filter *sfilter) #endif /* SECCOMP_ARCH_NATIVE */ /** - * seccomp_attach_filter: validate and attach filter + * seccomp_do_attach_filter: validate and attach filter * @flags: flags to change filter behavior * @filter: seccomp filter to add to the current process * @@ -873,8 +873,8 @@ static void seccomp_cache_prepare(struct seccomp_filter *sfilter) * seccomp mode or did not have an ancestral seccomp filter * - in NEW_LISTENER mode: the fd of the new listener */ -static long seccomp_attach_filter(unsigned int flags, - struct seccomp_filter *filter) +static long seccomp_do_attach_filter(unsigned int flags, + struct seccomp_filter *filter) { unsigned long total_insns; struct seccomp_filter *walker; @@ -1969,7 +1969,7 @@ static long seccomp_set_mode_filter(unsigned int flags, goto out; } - ret = seccomp_attach_filter(flags, prepared); + ret = seccomp_do_attach_filter(flags, prepared); if (ret) goto out; /* Do not free the successfully attached filter. */ @@ -2050,6 +2050,62 @@ static long seccomp_load_filter(const char __user *filter) out: return ret; } + +static long seccomp_attach_filter(const char __user *ufd) +{ + const unsigned long seccomp_mode = SECCOMP_MODE_FILTER; + struct seccomp_filter *sfilter; + struct bpf_prog *prog; + struct file *filp; + int flags = 0; + int fd, ret; + + if (copy_from_user(&fd, ufd, sizeof(fd))) + return -EFAULT; + + filp = fget(fd); + if (!filp) + return -EBADF; + + if (filp->f_op != &bpf_prog_fops) { + ret = -EINVAL; + goto out; + } + + prog = filp->private_data; + + sfilter = kzalloc(sizeof(*sfilter), GFP_KERNEL | __GFP_NOWARN); + if (!sfilter) { + ret = -ENOMEM; + goto out; + } + + sfilter->prog = prog; + refcount_set(&sfilter->refs, 1); + refcount_set(&sfilter->users, 1); + mutex_init(&sfilter->notify_lock); + init_waitqueue_head(&sfilter->wqh); + + spin_lock_irq(¤t->sighand->siglock); + + ret = -EINVAL; + if (!seccomp_may_assign_mode(seccomp_mode)) + goto out_unlock; + + ret = seccomp_do_attach_filter(flags, sfilter); + if (ret) + goto out_unlock; + + sfilter = NULL; + seccomp_assign_mode(current, seccomp_mode, flags); + +out_unlock: + spin_unlock_irq(¤t->sighand->siglock); + seccomp_filter_free(sfilter); +out: + fput(filp); + return ret; +} #else static inline long seccomp_set_mode_filter(unsigned int flags, const char __user *filter) @@ -2061,6 +2117,11 @@ static inline long seccomp_load_filter(const char __user *filter) { return -EINVAL; } + +static inline long seccomp_attach_filter(const char __user *ufd) +{ + return -EINVAL; +} #endif static long seccomp_get_action_avail(const char __user *uaction) @@ -2127,6 +2188,11 @@ static long do_seccomp(unsigned int op, unsigned int flags, return -EINVAL; return seccomp_load_filter(uargs); + case SECCOMP_ATTACH_FILTER: + if (flags != 0) + return -EINVAL; + + return seccomp_attach_filter(uargs); default: return -EINVAL; }