In the Linux kernel, the following vulnerability has been resolved: usb: cdns3: Fix NULL pointer dereference in cdns3_pci_probe The Cadenc

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

usb: cdns3: Fix NULL pointer dereference in cdns3_pci_probe

The Cadence USBSS controller is a two-function PCI device. The first
probed function allocates the driver data and stores it with
pci_set_drvdata(), while the second function reuses it via
pci_get_drvdata() when pci_is_enabled() reports that the first
function has already been probed.

When the second function is probed while the first one has been
enabled but has not yet set its driver data, pci_get_drvdata()
returns NULL, and the subsequent wrap->devfn assignment dereferences
a NULL pointer and crashes the kernel.
logs:
Call trace:
cdns3_pci_probe+0xa4/0x300
local_pci_probe+0x44/0xa8
pci_call_probe+0x54/0x158
pci_device_probe+0x84/0x100
really_probe+0x184/0x3d0
__driver_probe_device+0x80/0x178
driver_probe_device+0x44/0xe8
__driver_attach+0xec/0x1f8
bus_for_each_dev+0x7c/0xe0
driver_attach+0x28/0x38
bus_add_driver+0x110/0x238
driver_register+0x64/0x128
__pci_register_driver+0x50/0x60
cdns3_pci_driver_init+0x28/0x38
do_one_initcall+0x5c/0x280
do_initcalls+0x104/0x1d8
kernel_init_freeable+0x140/0x218
kernel_init+0x28/0x1f8
ret_from_fork+0x10/0x20

Return -EPROBE_DEFER in this case so that probing is retried after
the first function has completed its probe.