CTR_DRBG is an approved PRNG for FIPS compliance, defined in NIST SP800-90A. Linux's
/dev/random is, in principle, a suitable entropy source per NIST SP800-90B, but whether it is suitable in your particular use case depends on where the Linux kernel itself can obtain entropy. Having a hardware RNG (such as RDRAND on modern Intel CPUs) would raise fewer questions during the certification.
Beyond that, a FIPS 140 level 2 certification includes some actual security requirements (unlike level 1), so it isn't enough (but it is necessary) to use approved algorithms. Getting your product certified requires meeting all the other requirements of the certification (logging, scrubbing of data, operator authentication, pointless self-tests, etc.) and satisfying the evaluator that you've met all the requirements.