bnxt_en: Mask the bd_cnt field in the TX BD properly
In the Linux kernel, the following vulnerability has been resolved:
bnxt_en: Mask the bd_cnt field in the TX BD properly
The bd_cnt field in the TX BD specifies the total number of BDs for the TX packet. The bd_cnt field has 5 bits and the maximum number supported is 32 with the value 0.
CONFIG_MAX_SKB_FRAGS can be modified and the total number of SKB fragments can approach or exceed the maximum supported by the chip. Add a macro to properly mask the bd_cnt field so that the value 32 will be properly masked and set to 0 in the bd_cnd field.
Without this patch, the out-of-range bd_cnt value will corrupt the TX BD and may cause TX timeout.
The next patch will check for values exceeding 32.