From patchwork Tue Jun 16 15:33:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 11608249 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B7E4092A for ; Tue, 16 Jun 2020 16:20:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A188D21534 for ; Tue, 16 Jun 2020 16:20:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592324412; bh=nlJdig9ZgoQ+1epDga6Pnedfd5LFOzlP0peHjt3qs3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=iexYgU7B0KHiDI5sq6l58vZAB3+/kqVVqPGEAgEuR7wHWO1pBTjJbckocrhDGgp69 M9Ln0SmYBYBo7cGKjEZOKECkyzxQiwptF+J5jOoLgmM3nbpDUA11ALFUBlpQ5O6mxM 1+8mdB6BNtheM49+vV+o0UpMJiGsWZ+eoR1DbotU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730055AbgFPPgs (ORCPT ); Tue, 16 Jun 2020 11:36:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:47750 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730027AbgFPPgr (ORCPT ); Tue, 16 Jun 2020 11:36:47 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9CA7220E65; Tue, 16 Jun 2020 15:36:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592321806; bh=nlJdig9ZgoQ+1epDga6Pnedfd5LFOzlP0peHjt3qs3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SBIdnB2BJOTRKy547WtHybe+ZWYDojnbycnoLtHdKWMybOgf2ikAyaMNu8Ivpg7hu iCQyyyPtqizRWciJDwJavGjiBIV3eUQcN+bDjnhku09vgzDWJMV8n5o0n9LU437XMf /wPax7EFoNCweItY7Zr22fYMzLZYlRU5ECEPGJqc= 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, Sasha Levin Subject: [PATCH 5.4 023/134] padata: add separate cpuhp node for CPUHP_PADATA_DEAD Date: Tue, 16 Jun 2020 17:33:27 +0200 Message-Id: <20200616153101.847913241@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200616153100.633279950@linuxfoundation.org> References: <20200616153100.633279950@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org From: Daniel Jordan [ Upstream commit 3c2214b6027ff37945799de717c417212e1a8c54 ] 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: Sasha Levin --- include/linux/padata.h | 6 ++++-- kernel/padata.c | 14 ++++++++------ 2 files changed, 12 insertions(+), 8 deletions(-) diff --git a/include/linux/padata.h b/include/linux/padata.h index cccab7a59787..fa35dcfbd13f 100644 --- a/include/linux/padata.h +++ b/include/linux/padata.h @@ -145,7 +145,8 @@ struct padata_shell { /** * 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. * @parallel_wq: The workqueue used for parallel work. * @serial_wq: The workqueue used for serial work. * @pslist: List of padata_shell objects attached to this instance. @@ -160,7 +161,8 @@ struct padata_shell { * @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 *parallel_wq; struct workqueue_struct *serial_wq; struct list_head pslist; diff --git a/kernel/padata.c b/kernel/padata.c index c4b774331e46..92a4867e8adc 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -782,7 +782,7 @@ static int padata_cpu_online(unsigned int cpu, struct hlist_node *node) 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; @@ -797,7 +797,7 @@ static int padata_cpu_dead(unsigned int cpu, struct hlist_node *node) 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; @@ -813,8 +813,9 @@ 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 WARN_ON(!list_empty(&pinst->pslist)); @@ -1020,9 +1021,10 @@ static struct padata_instance *padata_alloc(const char *name, 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 put_online_cpus();