Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EBA3FC433F5 for ; Tue, 16 Nov 2021 02:19:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D05E760EB9 for ; Tue, 16 Nov 2021 02:19:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238171AbhKPCVo (ORCPT ); Mon, 15 Nov 2021 21:21:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:55444 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238404AbhKORks (ORCPT ); Mon, 15 Nov 2021 12:40:48 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2A3B0632EB; Mon, 15 Nov 2021 17:26:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1636997217; bh=iLa9WfAbNrjGOghi6vyGFT04Eby8oajpTgdFsX6tfws=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qaIgnngOwXt0soUp9rwV3ICbQjiwmt8xkgCj6UlavrZQUiS76qfi/8LOBz50KalaQ bfk/bylMVQiomNiqAEv/lSveFMgxtunpyxIUGEQn4FM02OTR8bbCXlKcI3hyvh+p9X QYf/PGGCukzbih0OFsS3qo+xgcLOH0MZhiB82g4A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lorenz Bauer , Alexei Starovoitov , Sasha Levin Subject: [PATCH 5.10 067/575] bpf: Prevent increasing bpf_jit_limit above max Date: Mon, 15 Nov 2021 17:56:32 +0100 Message-Id: <20211115165345.962150910@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165343.579890274@linuxfoundation.org> References: <20211115165343.579890274@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lorenz Bauer [ Upstream commit fadb7ff1a6c2c565af56b4aacdd086b067eed440 ] Restrict bpf_jit_limit to the maximum supported by the arch's JIT. Signed-off-by: Lorenz Bauer Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211014142554.53120-4-lmb@cloudflare.com Signed-off-by: Sasha Levin --- include/linux/filter.h | 1 + kernel/bpf/core.c | 4 +++- net/core/sysctl_net_core.c | 2 +- 3 files changed, 5 insertions(+), 2 deletions(-) diff --git a/include/linux/filter.h b/include/linux/filter.h index 822b701c803d1..bc6ce4b202a80 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -998,6 +998,7 @@ extern int bpf_jit_enable; extern int bpf_jit_harden; extern int bpf_jit_kallsyms; extern long bpf_jit_limit; +extern long bpf_jit_limit_max; typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size); diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 72e4bf0ee5460..d3a1f25f8ec2e 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -528,6 +528,7 @@ int bpf_jit_enable __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_DEFAULT_ON); int bpf_jit_kallsyms __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_DEFAULT_ON); int bpf_jit_harden __read_mostly; long bpf_jit_limit __read_mostly; +long bpf_jit_limit_max __read_mostly; static void bpf_prog_ksym_set_addr(struct bpf_prog *prog) @@ -821,7 +822,8 @@ u64 __weak bpf_jit_alloc_exec_limit(void) static int __init bpf_jit_charge_init(void) { /* Only used as heuristic here to derive limit. */ - bpf_jit_limit = min_t(u64, round_up(bpf_jit_alloc_exec_limit() >> 2, + bpf_jit_limit_max = bpf_jit_alloc_exec_limit(); + bpf_jit_limit = min_t(u64, round_up(bpf_jit_limit_max >> 2, PAGE_SIZE), LONG_MAX); return 0; } diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c index d86d8d11cfe4a..2e0a4378e778a 100644 --- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -419,7 +419,7 @@ static struct ctl_table net_core_table[] = { .mode = 0600, .proc_handler = proc_dolongvec_minmax_bpf_restricted, .extra1 = &long_one, - .extra2 = &long_max, + .extra2 = &bpf_jit_limit_max, }, #endif { -- 2.33.0