CVE-2021-47564

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

net: marvell: prestera: fix double free issue on err path

fix error path handling in prestera_bridge_port_join() that
cases prestera driver to crash (see below).

Trace:
Internal error: Oops: 96000044 [#1] SMP
Modules linked in: prestera_pci prestera uio_pdrv_genirq
CPU: 1 PID: 881 Comm: ip Not tainted 5.15.0 #1
pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=–)
pc : prestera_bridge_destroy+0x2c/0xb0 [prestera]
lr : prestera_bridge_port_join+0x2cc/0x350 [prestera]
sp : ffff800011a1b0f0
…
x2 : ffff000109ca6c80 x1 : dead000000000100 x0 : dead000000000122
Call trace:
prestera_bridge_destroy+0x2c/0xb0 [prestera]
prestera_bridge_port_join+0x2cc/0x350 [prestera]
prestera_netdev_port_event.constprop.0+0x3c4/0x450 [prestera]
prestera_netdev_event_handler+0xf4/0x110 [prestera]
raw_notifier_call_chain+0x54/0x80
call_netdevice_notifiers_info+0x54/0xa0
__netdev_upper_dev_link+0x19c/0x380