bnxt_en: fix OOB access in DBG_BUF_PRODUCER async event handler

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

bnxt_en: fix OOB access in DBG_BUF_PRODUCER async event handler

The ASYNC_EVENT_CMPL_EVENT_ID_DBG_BUF_PRODUCER handler in

bnxt_async_event_process() uses a firmware-supplied 'type' field

directly as an index into bp->bs_trace[] without bounds validation.

The 'type' field is a 16-bit value extracted from DMA-mapped completion

ring memory that the NIC writes directly to host RAM. A malicious or

compromised NIC can supply any value from 0 to 65535, causing an

out-of-bounds access into kernel heap memory.

The bnxt_bs_trace_check_wrap() call then dereferences bs_trace->magic_byte

and writes to bs_trace->last_offset and bs_trace->wrapped, leading to

kernel memory corruption or a crash.

Fix by adding a bounds check and defining BNXT_TRACE_MAX as

DBG_LOG_BUFFER_FLUSH_REQ_TYPE_ERR_QPC_TRACE + 1 to cover all currently

defined firmware trace types (0x0 through 0xc).