dda7e89e53
The pointer from a xhci usb virt device to its root hub port
(vdev->rhub_port) is set later when device is addressed, not while
vdev is allocated.
Tracepoints dereferenced this rhub_port pointer when freeing the virt
device, which causes null pointer dereference if tracing is enabled
and device is freed before addressed.
This can happen if tracing is enabled and xhci driver is unloaded before
a device is fully enumerated, or initial enumeration fails and device
is reset and freed before retry.
Don't dereference the rhub_port or show port numbers when tracing
xhci_free_virt_device(). This info is not very useful anyway.
Print the more useful slot id instead
Fixes: 06790c19086f ("xhci: replace real & fake port with pointer to root hub port")
Reported-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Closes: https://lore.kernel.org/linux-usb/20240402005007.klv2ij727fkz7rpd@synopsys.com/
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20240404121106.2842417-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.