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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E72A1C433FE for ; Wed, 24 Nov 2021 12:44:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343541AbhKXMrT (ORCPT ); Wed, 24 Nov 2021 07:47:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:51740 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345855AbhKXMoO (ORCPT ); Wed, 24 Nov 2021 07:44:14 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0FA2161221; Wed, 24 Nov 2021 12:26:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637756773; bh=KOE7QOMhpEINvh2hGUqlrpZHncZ0wr/2/1qNtEkU/Xk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LAMMZgnb7mmKQTE6zDaqXcKfkZNIExa8+nGBHd418EHbUehFFdJlDjrbRLolATxZW eYKg6D1iqpPoCdwhN5x9+gu1GIYItj/DSzxA9c/kszXFKZR9H4CGHPk+UlAOcSvvhR q43lC0H6a4zpi47/WL5MhQrzt2utlw+krXEsG+1E= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Gleixner , Bjorn Helgaas Subject: [PATCH 4.14 201/251] PCI/MSI: Destroy sysfs before freeing entries Date: Wed, 24 Nov 2021 12:57:23 +0100 Message-Id: <20211124115717.252469172@linuxfoundation.org> X-Mailer: git-send-email 2.34.0 In-Reply-To: <20211124115710.214900256@linuxfoundation.org> References: <20211124115710.214900256@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: Thomas Gleixner commit 3735459037114d31e5acd9894fad9aed104231a0 upstream. free_msi_irqs() frees the MSI entries before destroying the sysfs entries which are exposing them. Nothing prevents a concurrent free while a sysfs file is read and accesses the possibly freed entry. Move the sysfs release ahead of freeing the entries. Fixes: 1c51b50c2995 ("PCI/MSI: Export MSI mode using attributes, not kobjects") Signed-off-by: Thomas Gleixner Reviewed-by: Greg Kroah-Hartman Cc: Bjorn Helgaas Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/87sfw5305m.ffs@tglx Signed-off-by: Greg Kroah-Hartman --- drivers/pci/msi.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -372,18 +372,6 @@ static void free_msi_irqs(struct pci_dev for (i = 0; i < entry->nvec_used; i++) BUG_ON(irq_has_action(entry->irq + i)); - pci_msi_teardown_msi_irqs(dev); - - list_for_each_entry_safe(entry, tmp, msi_list, list) { - if (entry->msi_attrib.is_msix) { - if (list_is_last(&entry->list, msi_list)) - iounmap(entry->mask_base); - } - - list_del(&entry->list); - free_msi_entry(entry); - } - if (dev->msi_irq_groups) { sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups); msi_attrs = dev->msi_irq_groups[0]->attrs; @@ -399,6 +387,18 @@ static void free_msi_irqs(struct pci_dev kfree(dev->msi_irq_groups); dev->msi_irq_groups = NULL; } + + pci_msi_teardown_msi_irqs(dev); + + list_for_each_entry_safe(entry, tmp, msi_list, list) { + if (entry->msi_attrib.is_msix) { + if (list_is_last(&entry->list, msi_list)) + iounmap(entry->mask_base); + } + + list_del(&entry->list); + free_msi_entry(entry); + } } static void pci_intx_for_msi(struct pci_dev *dev, int enable)