From patchwork Thu Apr 28 09:23:21 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zixuan Fu X-Patchwork-Id: 567434 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 7BCD5C433FE for ; Thu, 28 Apr 2022 09:46:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230283AbiD1JuI (ORCPT ); Thu, 28 Apr 2022 05:50:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58594 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346747AbiD1J04 (ORCPT ); Thu, 28 Apr 2022 05:26:56 -0400 Received: from mail-pj1-x1034.google.com (mail-pj1-x1034.google.com [IPv6:2607:f8b0:4864:20::1034]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6EEF97B556; Thu, 28 Apr 2022 02:23:42 -0700 (PDT) Received: by mail-pj1-x1034.google.com with SMTP id p6so3795741pjm.1; Thu, 28 Apr 2022 02:23:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=4R456a2EKx3/Cjhoycmuudv2QP7/h6tZBuPXNUpi9fk=; b=I+lUa/of4zMx/MbE0mRhv6Lk3HLDIsjTKSRtN47KbE4VORjOEUzVMjpx7JVYN11vYq AfpM4QSpe0Ik/dIP4mDt0EaSADIoqtFhYF43sGbGCo3rt1/IhmtHifBK9CuZpTPHJFCI AW686YkIXIB9N2V0pRQGkWIGkuMtmuKksSRk8/+ufkn7drQ4VeJZA1N4HAzREAPhojIE VgQeCdc4/jspzPgBu1zWwC91ngQEG3JL99e2KPuYz7tOm7MEhiUqXB3eovWZo8v9GfwR 5RHYuj60FOLwCCA7qt6MKNsR+0ldk3HmvNK042XMJeG+rPK86qQBtnJPv80pBdWeyGA0 J5Ww== 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:mime-version :content-transfer-encoding; bh=4R456a2EKx3/Cjhoycmuudv2QP7/h6tZBuPXNUpi9fk=; b=zDsFRmz2nDD5OLEtAu1iTUJIUIVS7WVN8weqLp3qtAwXFHXTJ6R1rsTsZpOI74ayBK 3YahiyVezX0weDSV1bQwdEIY2uWPdr1JaaG2KHO8NWtDg2+B/aJS7Y0VGBZKdwPNb9hg z3bOBdTNNmic2lcszRCe5BRUp9oD1mbT1MfcozdKwaQis0Kh2AgaP0GVjpHtUOEDc6mQ 47JAtLjGiniZnb2D/9bc2o6xPoOa5Wp/qH48f9WPC+UZBWuGfPcYXYr74EzdooT766Ej itg1E5ybuZPvUt107Bc6wGQ5RjL6lveqjIYYC3lPJORCFqjBUjZNHi4YzG8Patt4KEpc Roqg== X-Gm-Message-State: AOAM533GGP0EK+R28UKmfD5C7PrULNVvlktO2EgPKPI29NYjshFt+kdR jT6EIDAZpXnlSRbVlhidxTE= X-Google-Smtp-Source: ABdhPJxDGLtFG2tk8d7m9YtfFxcyKP2ifBm7uCBtAeOK056rRBExu2Z4vCN3ZgZGlvlePmI57yzjiQ== X-Received: by 2002:a17:90b:1b4d:b0:1d9:bc90:f7ea with SMTP id nv13-20020a17090b1b4d00b001d9bc90f7eamr13052241pjb.223.1651137821789; Thu, 28 Apr 2022 02:23:41 -0700 (PDT) Received: from localhost ([166.111.139.106]) by smtp.gmail.com with ESMTPSA id b7-20020a056a00114700b004f7be3231d6sm22189732pfm.7.2022.04.28.02.23.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Apr 2022 02:23:41 -0700 (PDT) From: Zixuan Fu To: mathias.nyman@intel.com, gregkh@linuxfoundation.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, baijiaju1990@gmail.com, Zixuan Fu , TOTE Robot Subject: [PATCH v2 resend] drivers: usb: host: fix NULL pointer dereferences triggered by unhandled errors in xhci_create_rhub_port_array() Date: Thu, 28 Apr 2022 17:23:21 +0800 Message-Id: <20220428092321.3011983-1-r33s3n6@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org In xhci_create_rhub_port_array(), when rhub->num_ports is zero, rhub->ports would not be set; when kcalloc_node() fails, rhub->ports would be set to NULL. In these two cases, xhci_create_rhub_port_array() just returns void, and thus its callers are unaware of the error. Then rhub->ports is dereferenced in xhci_usb3_hub_descriptor() or xhci_usb2_hub_descriptor(). To fix the bug, xhci_setup_port_arrays() should return an integer to indicate a possible error, and its callers should handle the error. In the driver, xhci_create_rhub_port_array() is only used in xhci_setup_port_arrays(), and only xhci_mem_init() calls xhci_setup_port_arrays() and does all cleanup work when it fails. Specifically, xhci_mem_init() calls xhci_mem_cleanup(), which eventually calls kfree(xhci->usb2_rhub.ports) and kfree(xhci->usb3_rhub.ports). For this reason, when xhci_create_rhub_port_array() fails, xhci_setup_port_arrays() should return the error code directly, without freeing the memory allocated in this function. The error log in our fault-injection testing is shown as follows: [ 24.001309] BUG: kernel NULL pointer dereference, address: 0000000000000000 ... [ 24.003992] RIP: 0010:xhci_hub_control+0x3f5/0x60d0 [xhci_hcd] ... [ 24.009803] Call Trace: [ 24.010014] [ 24.011310] usb_hcd_submit_urb+0x1233/0x1fd0 [ 24.017071] usb_start_wait_urb+0x115/0x310 [ 24.017641] usb_control_msg+0x28a/0x450 [ 24.019046] hub_probe+0xb16/0x2320 [ 24.019757] usb_probe_interface+0x4f1/0x930 [ 24.019765] really_probe+0x33d/0x970 [ 24.019768] __driver_probe_device+0x157/0x210 [ 24.019772] driver_probe_device+0x4f/0x340 [ 24.019775] __device_attach_driver+0x2ee/0x3a0 ... Reported-by: TOTE Robot Signed-off-by: Zixuan Fu --- v2: * Explain the reason why xhci_setup_port_arrays() returns without freeing the memory in error handling code. Thank Greg KH for helpful advice. --- drivers/usb/host/xhci-mem.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index bbb27ee2c6a3..024515346c39 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -2235,7 +2235,7 @@ static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports, /* FIXME: Should we disable ports not in the Extended Capabilities? */ } -static void xhci_create_rhub_port_array(struct xhci_hcd *xhci, +static int xhci_create_rhub_port_array(struct xhci_hcd *xhci, struct xhci_hub *rhub, gfp_t flags) { int port_index = 0; @@ -2243,11 +2243,11 @@ static void xhci_create_rhub_port_array(struct xhci_hcd *xhci, struct device *dev = xhci_to_hcd(xhci)->self.sysdev; if (!rhub->num_ports) - return; + return -EINVAL; rhub->ports = kcalloc_node(rhub->num_ports, sizeof(*rhub->ports), flags, dev_to_node(dev)); if (!rhub->ports) - return; + return -ENOMEM; for (i = 0; i < HCS_MAX_PORTS(xhci->hcs_params1); i++) { if (xhci->hw_ports[i].rhub != rhub || @@ -2259,6 +2259,7 @@ static void xhci_create_rhub_port_array(struct xhci_hcd *xhci, if (port_index == rhub->num_ports) break; } + return 0; } /* @@ -2277,6 +2278,7 @@ static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t flags) int cap_count = 0; u32 cap_start; struct device *dev = xhci_to_hcd(xhci)->self.sysdev; + int ret; num_ports = HCS_MAX_PORTS(xhci->hcs_params1); xhci->hw_ports = kcalloc_node(num_ports, sizeof(*xhci->hw_ports), @@ -2367,8 +2369,13 @@ static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t flags) * Not sure how the USB core will handle a hub with no ports... */ - xhci_create_rhub_port_array(xhci, &xhci->usb2_rhub, flags); - xhci_create_rhub_port_array(xhci, &xhci->usb3_rhub, flags); + ret = xhci_create_rhub_port_array(xhci, &xhci->usb2_rhub, flags); + if (ret) + return ret; + + ret = xhci_create_rhub_port_array(xhci, &xhci->usb3_rhub, flags); + if (ret) + return ret; return 0; }