Fix out-of-bounds write when parsing tcp.flags#302
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The payload pointer is converted into an `enum bf_tcp_flag *` value and set to 0 (`*flag = 0`). However, the payload is 1 byte while a `bf_tcp_flag` enum type is 4, leading to out-of-bounds access. Use `uint8_t` to represent the payload, and add a static assertion to `enum bf_tcp_flag` to ensure we never have more than 8 values to ensure the bitmask can still fit in `uint8_t`.
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The payload pointer is converted into an
enum bf_tcp_flag *value and set to 0 (*flag = 0). However, the payload is 1 byte while abf_tcp_flagenum type is 4, leading to out-of-bounds access.Use
uint8_tto represent the payload, and add a static assertion toenum bf_tcp_flagto ensure we never have more than 8 values to ensure the bitmask can still fit inuint8_t.