CVE-2021-47424

In the Linux kernel, the following vulnerability has been resolved: i40e:
Fix freeing of uninitialized misc IRQ vector When VSI set up failed in
i40e_probe() as part of PF switch set up driver was trying to free misc IRQ
vectors in i40e_clear_interrupt_scheme and produced a kernel Oops: Trying
to free already-free IRQ 266 WARNING: CPU: 0 PID: 5 at
kernel/irq/manage.c:1731 __free_irq+0x9a/0x300 Workqueue: events
work_for_cpu_fn RIP: 0010:__free_irq+0x9a/0x300 Call Trace: ?
synchronize_irq+0x3a/0xa0 free_irq+0x2e/0x60
i40e_clear_interrupt_scheme+0x53/0x190 [i40e]
i40e_probe.part.108+0x134b/0x1a40 [i40e] ? kmem_cache_alloc+0x158/0x1c0 ?
acpi_ut_update_ref_count.part.1+0x8e/0x345 ?
acpi_ut_update_object_reference+0x15e/0x1e2 ? strstr+0x21/0x70 ?
irq_get_irq_data+0xa/0x20 ? mp_check_pin_attr+0x13/0xc0 ?
irq_get_irq_data+0xa/0x20 ? mp_map_pin_to_irq+0xd3/0x2f0 ?
acpi_register_gsi_ioapic+0x93/0x170 ? pci_conf1_read+0xa4/0x100 ?
pci_bus_read_config_word+0x49/0x70 ? do_pci_enable_device+0xcc/0x100
local_pci_probe+0x41/0x90 work_for_cpu_fn+0x16/0x20
process_one_work+0x1a7/0x360 worker_thread+0x1cf/0x390 ?
create_worker+0x1a0/0x1a0 kthread+0x112/0x130 ?
kthread_flush_work_fn+0x10/0x10 ret_from_fork+0x1f/0x40 The problem is that
at that point misc IRQ vectors were not allocated yet and we get a call
trace that driver is trying to free already free IRQ vectors. Add a check
in i40e_clear_interrupt_scheme for __I40E_MISC_IRQ_REQUESTED PF state
before calling i40e_free_misc_vector. This state is set only if misc IRQ
vectors were properly initialized.