CVE-2026-98763: usb: core: clear both ep_in and ep_out for non-ep0 control endpoints

CVE-2026-98763: usb: core: clear both ep_in and ep_out for non-ep0 control endpoints

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

usb: core: clear both ep_in and ep_out for non-ep0 control endpoints

In usb_enable_endpoint(), non-zero control endpoints (where
usb_endpoint_xfer_control(&ep->desc) is true) populate both
dev->ep_in[epnum] and dev->ep_out[epnum] with the same struct
usb_host_endpoint pointer.

However, usb_disable_endpoint() only clears either dev->ep_out[epnum] or
dev->ep_in[epnum] depending on the direction bit of epaddr when
reset_hardware is set, leaving the opposite direction's array slot
pointing to the disabled/freed endpoint.

Clear both dev->ep_out[epnum] and dev->ep_in[epnum] when disabling a
non-ep0 control endpoint with reset_hardware set, and update the
function kerneldoc accordingly.

Tested in QEMU against Linux 7.3.0-rc3 using dummy_hcd and raw-gadget to
enumerate a USB device with a non-zero control endpoint
(bEndpointAddress 0x01, bmAttributes USB_ENDPOINT_XFER_CONTROL),
verifying that both dev->ep_in[1] and dev->ep_out[1] are cleared when
the interface is disabled.

The Linux kernel CVE team has assigned CVE-2026-98763 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.12.113 with commit 7a9f61476b0e8002092a52ee8295edeeb0a28d1e
	Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.18.56 with commit 1da16c46b8d7101b74bc2d72a04e23cf5c7ddea1
	Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.2.10 with commit c50413ecb662ea43c7f487632c8114721743a277
	Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.3-rc6 with commit 0e8baa78d872f2db440d8b9ded946ab8dceb89eb

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-98763
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/usb/core/message.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/7a9f61476b0e8002092a52ee8295edeeb0a28d1e
	https://git.kernel.org/stable/c/1da16c46b8d7101b74bc2d72a04e23cf5c7ddea1
	https://git.kernel.org/stable/c/c50413ecb662ea43c7f487632c8114721743a277
	https://git.kernel.org/stable/c/0e8baa78d872f2db440d8b9ded946ab8dceb89eb