spi: hisi-sfc-v3xx: Return IRQ_NONE if no interrupts were detected

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

spi: hisi-sfc-v3xx: Return IRQ_NONE if no interrupts were detected

Return IRQ_NONE from the interrupt handler when no interrupt was

detected. Because an empty interrupt will cause a null pointer error:

Unable to handle kernel NULL pointer dereference at virtual

address 0000000000000008

Call trace:

complete+0x54/0x100

hisi_sfc_v3xx_isr+0x2c/0x40 [spi_hisi_sfc_v3xx]

__handle_irq_event_percpu+0x64/0x1e0

handle_irq_event+0x7c/0x1cc