Overview
About vulnerability
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.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 5.10.259 (+19 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| AlmaLinux 9.2 ESU | Planned | — |