From patchwork Fri Aug 6 08:15:07 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 492924 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 8158BC43214 for ; Fri, 6 Aug 2021 08:17:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 66D92611EF for ; Fri, 6 Aug 2021 08:17:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243919AbhHFISD (ORCPT ); Fri, 6 Aug 2021 04:18:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:46830 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243998AbhHFIQk (ORCPT ); Fri, 6 Aug 2021 04:16:40 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4A80F61205; Fri, 6 Aug 2021 08:16:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628237776; bh=5Abe2X7deOpV8qBiC/8PkTAVKIbX3prv6qZg1VjtK3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cj2/I7uev1BNNOEE4n2WQdONbrN0bsCNSiCIXCZE+iGvFu2gRmG5BLzMfyV2RPapQ hjkREHMTO4bJ4WEXy/pU4HQwBkoZSZzxbw8jcCGY3BK6d0X30OFqswiEy2kZfC2Efv VSyNeOHM9rjbz0qQnAvhISf1Tl1x1V9HU19gZ7Xk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Jordan , Herbert Xu , Steffen Klassert , linux-crypto@vger.kernel.org, Yang Yingliang Subject: [PATCH 4.19 16/16] padata: add separate cpuhp node for CPUHP_PADATA_DEAD Date: Fri, 6 Aug 2021 10:15:07 +0200 Message-Id: <20210806081111.662287213@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 3c2214b6027ff37945799de717c417212e1a8c54 upstream. Removing the pcrypt module triggers this: general protection fault, probably for non-canonical address 0xdead000000000122 CPU: 5 PID: 264 Comm: modprobe Not tainted 5.6.0+ #2 Hardware name: QEMU Standard PC RIP: 0010:__cpuhp_state_remove_instance+0xcc/0x120 Call Trace: padata_sysfs_release+0x74/0xce kobject_put+0x81/0xd0 padata_free+0x12/0x20 pcrypt_exit+0x43/0x8ee [pcrypt] padata instances wrongly use the same hlist node for the online and dead states, so __padata_free()'s second cpuhp remove call chokes on the node that the first poisoned. cpuhp multi-instance callbacks only walk forward in cpuhp_step->list and the same node is linked in both the online and dead lists, so the list corruption that results from padata_alloc() adding the node to a second list without removing it from the first doesn't cause problems as long as no instances are freed. Avoid the issue by giving each state its own node. Fixes: 894c9ef9780c ("padata: validate cpumask without removed CPU during offline") Signed-off-by: Daniel Jordan Cc: Herbert Xu Cc: Steffen Klassert Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Herbert Xu Signed-off-by: Yang Yingliang Signed-off-by: Greg Kroah-Hartman --- include/linux/padata.h | 6 ++++-- kernel/padata.c | 14 ++++++++------ 2 files changed, 12 insertions(+), 8 deletions(-) --- a/include/linux/padata.h +++ b/include/linux/padata.h @@ -138,7 +138,8 @@ struct parallel_data { /** * struct padata_instance - The overall control structure. * - * @cpu_notifier: cpu hotplug notifier. + * @cpu_online_node: Linkage for CPU online callback. + * @cpu_dead_node: Linkage for CPU offline callback. * @wq: The workqueue in use. * @pd: The internal control structure. * @cpumask: User supplied cpumasks for parallel and serial works. @@ -150,7 +151,8 @@ struct parallel_data { * @flags: padata flags. */ struct padata_instance { - struct hlist_node node; + struct hlist_node cpu_online_node; + struct hlist_node cpu_dead_node; struct workqueue_struct *wq; struct parallel_data *pd; struct padata_cpumask cpumask; --- a/kernel/padata.c +++ b/kernel/padata.c @@ -748,7 +748,7 @@ static int padata_cpu_online(unsigned in struct padata_instance *pinst; int ret; - pinst = hlist_entry_safe(node, struct padata_instance, node); + pinst = hlist_entry_safe(node, struct padata_instance, cpu_online_node); if (!pinst_has_cpu(pinst, cpu)) return 0; @@ -763,7 +763,7 @@ static int padata_cpu_dead(unsigned int struct padata_instance *pinst; int ret; - pinst = hlist_entry_safe(node, struct padata_instance, node); + pinst = hlist_entry_safe(node, struct padata_instance, cpu_dead_node); if (!pinst_has_cpu(pinst, cpu)) return 0; @@ -779,8 +779,9 @@ 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); + cpuhp_state_remove_instance_nocalls(CPUHP_PADATA_DEAD, + &pinst->cpu_dead_node); + cpuhp_state_remove_instance_nocalls(hp_online, &pinst->cpu_online_node); #endif padata_stop(pinst); @@ -964,9 +965,10 @@ static struct padata_instance *padata_al mutex_init(&pinst->lock); #ifdef CONFIG_HOTPLUG_CPU - cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, &pinst->node); + cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, + &pinst->cpu_online_node); cpuhp_state_add_instance_nocalls_cpuslocked(CPUHP_PADATA_DEAD, - &pinst->node); + &pinst->cpu_dead_node); #endif return pinst;