From patchwork Fri Sep 10 20:26:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= X-Patchwork-Id: 1526624 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4H5nTR4CTTz9sf8 for ; Sat, 11 Sep 2021 06:26:35 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233715AbhIJU1o (ORCPT ); Fri, 10 Sep 2021 16:27:44 -0400 Received: from mail-lf1-f47.google.com ([209.85.167.47]:46599 "EHLO mail-lf1-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233733AbhIJU1m (ORCPT ); Fri, 10 Sep 2021 16:27:42 -0400 Received: by mail-lf1-f47.google.com with SMTP id t19so6390861lfe.13 for ; Fri, 10 Sep 2021 13:26:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=SCWGEafDm9+a2Gvdto/l8SUM0CdXaX/vrNhpnx0tOGg=; b=oiLg2BBp8CeqstP4eRMYLD73yQK8nbprLpEXvxroqiuPr4kfCzYtGuJxGdvVkoZYw0 YNwQTEoH8HP9LmjdYuHPL6xtXXWucRop7De/DeevzxfsnEngseN7EwVlFSrGYsT5BgfT j5XXtW//hB5ZrqgPRCocT4yYxup9n2UdVQnuOkzgFN0jhDjBAQDT/PZcBJnENlTLvVt3 e/sG+pmDRXHJ7G5FhexJP6P0qc4C5/4eu3euQ8JK5+1r922/4Npz3ax1e5FSFta2f4vC yu967JpR4wPBDU9WZNJKUCX6Ux6plvQOUWtdUJQV0T1xgqlvJDucH2Kkvz3ZTZSGwsNV oaFA== X-Gm-Message-State: AOAM531AyDJ8O+NSfY9xDvlihQYWWNN/efhTPbraXSeDOOqksOpZwDJH +it9zdXqtp1jgJ5CsWC4/Rs= X-Google-Smtp-Source: ABdhPJw9PsY3v1dNQCjFlM2XHn3SHsklA6wQYVyWe/n3qp0lbcsdZdAb2gHMJc/v6w/NIxZjjdMZIg== X-Received: by 2002:a05:6512:96f:: with SMTP id v15mr5083269lft.455.1631305589686; Fri, 10 Sep 2021 13:26:29 -0700 (PDT) Received: from workstation.lan ([95.155.85.46]) by smtp.gmail.com with ESMTPSA id a22sm657667lfb.17.2021.09.10.13.26.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 10 Sep 2021 13:26:29 -0700 (PDT) From: =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= To: Bjorn Helgaas Cc: Greg Kroah-Hartman , =?utf-8?q?Pali_Roh?= =?utf-8?q?=C3=A1r?= , "Oliver O'Halloran" , =?utf-8?q?Krzysztof_Ha=C5=82asa?= , linux-pci@vger.kernel.org Subject: [PATCH v2 4/7] PCI/sysfs: Only allow supported resource type in pci_mmap_resource() Date: Fri, 10 Sep 2021 20:26:20 +0000 Message-Id: <20210910202623.2293708-5-kw@linux.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210910202623.2293708-1-kw@linux.com> References: <20210910202623.2293708-1-kw@linux.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Currently, when the sysfs attributes for PCI resources are added dynamically, the mmap() callback will only ever be set when the underlying resource (a given BAR) has either the IORESOURCE_MEM (which currently is implied) or IORESOURCE_IO flag set and where the latter requires that the underlying architecture supports mmap() for I/O BARs, otherwise the callbacks are set to NULL and any attempt to read from such sysfs attribute will inherently fail. Following the conversion to the static sysfs objects, the mmap() callbacks will be always set for a given binary attribute (a particular sysfs object). Thus, a check is added to the pci_mmap_resource() function to ensure that a read against the underlying resource is supported and that either the IORESOURCE_MEM or IORESOURCE_IO flag is set with the platform supporting mmap() for I/O BARs as required. Signed-off-by: Krzysztof Wilczyński --- drivers/pci/pci-sysfs.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index e151d635fe04..2031b5da6bcf 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1051,6 +1051,10 @@ static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr, if (ret) return ret; + if (!(res->flags & IORESOURCE_MEM || + ((res->flags & IORESOURCE_IO) && arch_can_pci_mmap_io()))) + return -EIO; + if (res->flags & IORESOURCE_MEM && iomem_is_exclusive(res->start)) return -EINVAL;