All of lore.kernel.org
 help / color / mirror / Atom feed
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org, Alan Stern <stern@rowland.harvard.edu>,
	syzbot+3ae6a2b06f131ab9849f@syzkaller.appspotmail.com
Subject: [PATCH 5.4 05/18] USB: Fix "slab-out-of-bounds Write" bug in usb_hcd_poll_rh_status
Date: Fri, 14 Jan 2022 09:16:12 +0100	[thread overview]
Message-ID: <20220114081541.645093106@linuxfoundation.org> (raw)
In-Reply-To: <20220114081541.465841464@linuxfoundation.org>

From: Alan Stern <stern@rowland.harvard.edu>

commit 1d7d4c07932e04355d6e6528d44a2f2c9e354346 upstream.

When the USB core code for getting root-hub status reports was
originally written, it was assumed that the hub driver would be its
only caller.  But this isn't true now; user programs can use usbfs to
communicate with root hubs and get status reports.  When they do this,
they may use a transfer_buffer that is smaller than the data returned
by the HCD, which will lead to a buffer overflow error when
usb_hcd_poll_rh_status() tries to store the status data.  This was
discovered by syzbot:

BUG: KASAN: slab-out-of-bounds in memcpy include/linux/fortify-string.h:225 [inline]
BUG: KASAN: slab-out-of-bounds in usb_hcd_poll_rh_status+0x5f4/0x780 drivers/usb/core/hcd.c:776
Write of size 2 at addr ffff88801da403c0 by task syz-executor133/4062

This patch fixes the bug by reducing the amount of status data if it
won't fit in the transfer_buffer.  If some data gets discarded then
the URB's completion status is set to -EOVERFLOW rather than 0, to let
the user know what happened.

Reported-and-tested-by: syzbot+3ae6a2b06f131ab9849f@syzkaller.appspotmail.com
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/Yc+3UIQJ2STbxNua@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/core/hcd.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -753,6 +753,7 @@ void usb_hcd_poll_rh_status(struct usb_h
 {
 	struct urb	*urb;
 	int		length;
+	int		status;
 	unsigned long	flags;
 	char		buffer[6];	/* Any root hubs with > 31 ports? */
 
@@ -770,11 +771,17 @@ void usb_hcd_poll_rh_status(struct usb_h
 		if (urb) {
 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 			hcd->status_urb = NULL;
+			if (urb->transfer_buffer_length >= length) {
+				status = 0;
+			} else {
+				status = -EOVERFLOW;
+				length = urb->transfer_buffer_length;
+			}
 			urb->actual_length = length;
 			memcpy(urb->transfer_buffer, buffer, length);
 
 			usb_hcd_unlink_urb_from_ep(hcd, urb);
-			usb_hcd_giveback_urb(hcd, urb, 0);
+			usb_hcd_giveback_urb(hcd, urb, status);
 		} else {
 			length = 0;
 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);



  parent reply	other threads:[~2022-01-14  8:17 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-14  8:16 [PATCH 5.4 00/18] 5.4.172-rc1 review Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 01/18] workqueue: Fix unbind_workers() VS wq_worker_running() race Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 02/18] Bluetooth: btusb: fix memory leak in btusb_mtk_submit_wmt_recv_urb() Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 03/18] Bluetooth: bfusb: fix division by zero in send path Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 04/18] USB: core: Fix bug in resuming hubs handling of wakeup requests Greg Kroah-Hartman
2022-01-14  8:16 ` Greg Kroah-Hartman [this message]
2022-01-14  8:16 ` [PATCH 5.4 06/18] mmc: sdhci-pci: Add PCI ID for Intel ADL Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 07/18] veth: Do not record rx queue hint in veth_xmit Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 08/18] mfd: intel-lpss: Fix too early PM enablement in the ACPI ->probe() Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 09/18] drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 10/18] can: gs_usb: fix use of uninitialized variable, detach device on reception of invalid USB data Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 11/18] can: gs_usb: gs_can_start_xmit(): zero-initialize hf->{flags,reserved} Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 12/18] random: fix data race on crng_node_pool Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 13/18] random: fix data race on crng init time Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 14/18] random: fix crash on multiple early calls to add_bootloader_randomness() Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 15/18] media: Revert "media: uvcvideo: Set unique vdev name based in type" Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 16/18] staging: wlan-ng: Avoid bitwise vs logical OR warning in hfa384x_usb_throttlefn() Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 17/18] drm/i915: Avoid bitwise vs logical OR warning in snb_wm_latency_quirk() Greg Kroah-Hartman
2022-01-14  8:16 ` [PATCH 5.4 18/18] staging: greybus: fix stack size warning with UBSAN Greg Kroah-Hartman
2022-01-14 18:09 ` [PATCH 5.4 00/18] 5.4.172-rc1 review Jon Hunter
2022-01-14 20:15 ` Florian Fainelli
2022-01-15  0:26 ` Shuah Khan
2022-01-15  6:05 ` Naresh Kamboju
2022-01-15 11:09 ` Sudip Mukherjee
2022-01-15 16:38 ` Guenter Roeck

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220114081541.645093106@linuxfoundation.org \
    --to=gregkh@linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=stern@rowland.harvard.edu \
    --cc=syzbot+3ae6a2b06f131ab9849f@syzkaller.appspotmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.