From patchwork Fri Aug 6 08:15:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 12422957 X-Patchwork-Delegate: herbert@gondor.apana.org.au 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 38587C4320E for ; Fri, 6 Aug 2021 08:17:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 21840611B0 for ; Fri, 6 Aug 2021 08:17:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243797AbhHFISA (ORCPT ); Fri, 6 Aug 2021 04:18:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:46778 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243995AbhHFIQ3 (ORCPT ); Fri, 6 Aug 2021 04:16:29 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id B6A7E611EF; Fri, 6 Aug 2021 08:16:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628237774; bh=s2bWJEORa+DqWmMyAsTBwaCD6kYNZqRTyDUNsRsO6RQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hvatL+gZhNYnvtMQmtdMmXtiDfodx8xOY05MKAanGlbxo+s/RfmjEqcSv4pwKjpke nQx0m45OtYLPU4dYMxUFWXAWsZzofTVdGB4BD6Ba4rEa0qhiP9nCdZG5VvYz5JnYu2 iFeYBPsQG8dUBKx6dE5owPneuK3qoskUz++9aI9Q= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Jordan , Eric Biggers , Herbert Xu , Sebastian Andrzej Siewior , Steffen Klassert , Thomas Gleixner , linux-crypto@vger.kernel.org, Yang Yingliang Subject: [PATCH 4.19 15/16] padata: validate cpumask without removed CPU during offline Date: Fri, 6 Aug 2021 10:15:06 +0200 Message-Id: <20210806081111.628446735@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210806081111.144943357@linuxfoundation.org> References: <20210806081111.144943357@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org From: Daniel Jordan commit 894c9ef9780c5cf2f143415e867ee39a33ecb75d upstream. Configuring an instance's parallel mask without any online CPUs... echo 2 > /sys/kernel/pcrypt/pencrypt/parallel_cpumask echo 0 > /sys/devices/system/cpu/cpu1/online ...makes tcrypt mode=215 crash like this: divide error: 0000 [#1] SMP PTI CPU: 4 PID: 283 Comm: modprobe Not tainted 5.4.0-rc8-padata-doc-v2+ #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191013_105130-anatol 04/01/2014 RIP: 0010:padata_do_parallel+0x114/0x300 Call Trace: pcrypt_aead_encrypt+0xc0/0xd0 [pcrypt] crypto_aead_encrypt+0x1f/0x30 do_mult_aead_op+0x4e/0xdf [tcrypt] test_mb_aead_speed.constprop.0.cold+0x226/0x564 [tcrypt] do_test+0x28c2/0x4d49 [tcrypt] tcrypt_mod_init+0x55/0x1000 [tcrypt] ... cpumask_weight() in padata_cpu_hash() returns 0 because the mask has no CPUs. The problem is __padata_remove_cpu() checks for valid masks too early and so doesn't mark the instance PADATA_INVALID as expected, which would have made padata_do_parallel() return error before doing the division. Fix by introducing a second padata CPU hotplug state before CPUHP_BRINGUP_CPU so that __padata_remove_cpu() sees the online mask without @cpu. No need for the second argument to padata_replace() since @cpu is now already missing from the online mask. Fixes: 33e54450683c ("padata: Handle empty padata cpumasks") Signed-off-by: Daniel Jordan Cc: Eric Biggers Cc: Herbert Xu Cc: Sebastian Andrzej Siewior Cc: Steffen Klassert Cc: Thomas Gleixner Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Herbert Xu Signed-off-by: Yang Yingliang Signed-off-by: Greg Kroah-Hartman --- include/linux/cpuhotplug.h | 1 + kernel/padata.c | 18 ++++++++++++++---- 2 files changed, 15 insertions(+), 4 deletions(-) --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -59,6 +59,7 @@ enum cpuhp_state { CPUHP_IOMMU_INTEL_DEAD, CPUHP_LUSTRE_CFS_DEAD, CPUHP_AP_ARM_CACHE_B15_RAC_DEAD, + CPUHP_PADATA_DEAD, CPUHP_WORKQUEUE_PREP, CPUHP_POWER_NUMA_PREPARE, CPUHP_HRTIMERS_PREPARE, --- a/kernel/padata.c +++ b/kernel/padata.c @@ -682,7 +682,7 @@ static int __padata_remove_cpu(struct pa { struct parallel_data *pd = NULL; - if (cpumask_test_cpu(cpu, cpu_online_mask)) { + if (!cpumask_test_cpu(cpu, cpu_online_mask)) { if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) || !padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) @@ -758,7 +758,7 @@ static int padata_cpu_online(unsigned in return ret; } -static int padata_cpu_prep_down(unsigned int cpu, struct hlist_node *node) +static int padata_cpu_dead(unsigned int cpu, struct hlist_node *node) { struct padata_instance *pinst; int ret; @@ -779,6 +779,7 @@ static enum cpuhp_state hp_online; static void __padata_free(struct padata_instance *pinst) { #ifdef CONFIG_HOTPLUG_CPU + cpuhp_state_remove_instance_nocalls(CPUHP_PADATA_DEAD, &pinst->node); cpuhp_state_remove_instance_nocalls(hp_online, &pinst->node); #endif @@ -964,6 +965,8 @@ static struct padata_instance *padata_al #ifdef CONFIG_HOTPLUG_CPU cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, &pinst->node); + cpuhp_state_add_instance_nocalls_cpuslocked(CPUHP_PADATA_DEAD, + &pinst->node); #endif return pinst; @@ -1010,17 +1013,24 @@ static __init int padata_driver_init(voi int ret; ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "padata:online", - padata_cpu_online, - padata_cpu_prep_down); + padata_cpu_online, NULL); if (ret < 0) return ret; hp_online = ret; + + ret = cpuhp_setup_state_multi(CPUHP_PADATA_DEAD, "padata:dead", + NULL, padata_cpu_dead); + if (ret < 0) { + cpuhp_remove_multi_state(hp_online); + return ret; + } return 0; } module_init(padata_driver_init); static __exit void padata_driver_exit(void) { + cpuhp_remove_multi_state(CPUHP_PADATA_DEAD); cpuhp_remove_multi_state(hp_online); } module_exit(padata_driver_exit);