From patchwork Wed Aug 30 10:04:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Ricardo_Ca=C3=B1uelo?= X-Patchwork-Id: 13370470 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 18A07C83F17 for ; Wed, 30 Aug 2023 18:31:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236162AbjH3Sbh (ORCPT ); Wed, 30 Aug 2023 14:31:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243004AbjH3KEo (ORCPT ); Wed, 30 Aug 2023 06:04:44 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A69C51B0 for ; Wed, 30 Aug 2023 03:04:41 -0700 (PDT) Received: from localhost.localdomain (unknown [IPv6:2a0c:5a83:9103:1700:2f0:bfeb:cfb7:701b]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: rcn) by madras.collabora.co.uk (Postfix) with ESMTPSA id A84FC660724E; Wed, 30 Aug 2023 11:04:39 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1693389880; bh=PuY/PBzrtN+DuzEkT2l30ikI64ziIXGpjqQ2fSRGvyM=; h=From:To:Cc:Subject:Date:From; b=Mgpv8ZZw9O4bbQvGCDchH9+lZgBatmS4tHdC1aIgVabWSePDd3HIWmotuLaWSqifF ACNZTMa08Rmodx7pzqlsMXb1e1yOf2FByv54LQ2tQbCGko/f5FepWlIYuZxMmRNCc9 Eq1CKUpn6OmM2wxKbQx82pit/UofpYb7aAiYdpRTI8Wq84mDJWf4m9Y5+qNGr1nWeP hUVI/DFvD4DFwb4IFHyuy4Fv/7cHyXAbAqvwK5/VJS2LvI5qPLDgpOt2G+qijvBT75 0/Q97iKdUcv0+Y2UinoqbubNI+wrT+FN2Y8ffq7rYDRlKd0M6PG83oNYUQYwm+tDDa +5nAZVSqAWg5w== From: =?utf-8?q?Ricardo_Ca=C3=B1uelo?= To: gregkh@linuxfoundation.org Cc: stern@rowland.harvard.edu, linux-usb@vger.kernel.org, linux@roeck-us.net, kernel@collabora.com Subject: [PATCH] usb: hub: Guard against accesses to uninitialized BOS descriptors Date: Wed, 30 Aug 2023 12:04:18 +0200 Message-Id: <20230830100418.1952143-1-ricardo.canuelo@collabora.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 Many functions in drivers/usb/core/hub.c and drivers/usb/core/hub.h access fields inside udev->bos without checking if it was allocated and initialized. If usb_get_bos_descriptor() fails for whatever reason, udev->bos will be NULL and those accesses will result in a crash: BUG: kernel NULL pointer dereference, address: 0000000000000018 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 5 PID: 17818 Comm: kworker/5:1 Tainted: G W 5.15.108-18910-gab0e1cb584e1 #1 Hardware name: Google Kindred/Kindred, BIOS Google_Kindred.12672.413.0 02/03/2021 Workqueue: usb_hub_wq hub_event RIP: 0010:hub_port_reset+0x193/0x788 Code: 89 f7 e8 20 f7 15 00 48 8b 43 08 80 b8 96 03 00 00 03 75 36 0f b7 88 92 03 00 00 81 f9 10 03 00 00 72 27 48 8b 80 a8 03 00 00 <48> 83 78 18 00 74 19 48 89 df 48 8b 75 b0 ba 02 00 00 00 4c 89 e9 RSP: 0018:ffffab740c53fcf8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffa1bc5f678000 RCX: 0000000000000310 RDX: fffffffffffffdff RSI: 0000000000000286 RDI: ffffa1be9655b840 RBP: ffffab740c53fd70 R08: 00001b7d5edaa20c R09: ffffffffb005e060 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: ffffab740c53fd3e R14: 0000000000000032 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffffa1be96540000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 000000022e80c005 CR4: 00000000003706e0 Call Trace: hub_event+0x73f/0x156e ? hub_activate+0x5b7/0x68f process_one_work+0x1a2/0x487 worker_thread+0x11a/0x288 kthread+0x13a/0x152 ? process_one_work+0x487/0x487 ? kthread_associate_blkcg+0x70/0x70 ret_from_fork+0x1f/0x30 Fall back to a default behavior if the BOS descriptor isn't accessible and skip all the functionalities that depend on it: LPM support checks, Super Speed capabilitiy checks, U1/U2 states setup. Signed-off-by: Ricardo Cañuelo Cc: stable --- drivers/usb/core/hub.c | 25 ++++++++++++++++++++++--- drivers/usb/core/hub.h | 2 +- 2 files changed, 23 insertions(+), 4 deletions(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index a739403a9e45..7e2d092df893 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -151,6 +151,10 @@ int usb_device_supports_lpm(struct usb_device *udev) if (udev->quirks & USB_QUIRK_NO_LPM) return 0; + /* Skip if the device BOS descriptor couldn't be read */ + if (!udev->bos) + return 0; + /* USB 2.1 (and greater) devices indicate LPM support through * their USB 2.0 Extended Capabilities BOS descriptor. */ @@ -327,6 +331,10 @@ static void usb_set_lpm_parameters(struct usb_device *udev) if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER) return; + /* Skip if the device BOS descriptor couldn't be read */ + if (!udev->bos) + return; + hub = usb_hub_to_struct_hub(udev->parent); /* It doesn't take time to transition the roothub into U0, since it * doesn't have an upstream link. @@ -2715,13 +2723,17 @@ int usb_authorize_device(struct usb_device *usb_dev) static enum usb_ssp_rate get_port_ssp_rate(struct usb_device *hdev, u32 ext_portstatus) { - struct usb_ssp_cap_descriptor *ssp_cap = hdev->bos->ssp_cap; + struct usb_ssp_cap_descriptor *ssp_cap; u32 attr; u8 speed_id; u8 ssac; u8 lanes; int i; + if (!hdev->bos) + goto out; + + ssp_cap = hdev->bos->ssp_cap; if (!ssp_cap) goto out; @@ -4239,8 +4251,15 @@ static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev, enum usb3_link_state state) { int timeout; - __u8 u1_mel = udev->bos->ss_cap->bU1devExitLat; - __le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat; + __u8 u1_mel; + __le16 u2_mel; + + /* Skip if the device BOS descriptor couldn't be read */ + if (!udev->bos) + return; + + u1_mel = udev->bos->ss_cap->bU1devExitLat; + u2_mel = udev->bos->ss_cap->bU2DevExitLat; /* If the device says it doesn't have *any* exit latency to come out of * U1 or U2, it's probably lying. Assume it doesn't implement that link diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h index 37897afd1b64..d44dd7f6623e 100644 --- a/drivers/usb/core/hub.h +++ b/drivers/usb/core/hub.h @@ -153,7 +153,7 @@ static inline int hub_is_superspeedplus(struct usb_device *hdev) { return (hdev->descriptor.bDeviceProtocol == USB_HUB_PR_SS && le16_to_cpu(hdev->descriptor.bcdUSB) >= 0x0310 && - hdev->bos->ssp_cap); + hdev->bos && hdev->bos->ssp_cap); } static inline unsigned hub_power_on_good_delay(struct usb_hub *hub)