fork and execve to inherit unprivileged parent process' capabilities

В системе Linux непривилегированный пользователь запускает программу. Созданный процесс имеет возможности CAP_NET_RAW, CAP_NET_ADMIN с режимом эффективный, разрешенный, наследуемый . This process then creates a child process by calling fork and execv to invoke another program udhcpc, but the child process does not inherit the capabilities CAP_NET_RAW,CAP_NET_ADMIN as expected. Even though before setting the capabilities I have called prctl(PR_SET_KEEPCAPS, 1).

Any suggestion on what to do to inherit unprivileged parent process' capabilities upon fork followed by execve?