[krbdev.mit.edu #8704] Resource leak in read_secret_file()

[Bean Zhang via RT]

Hi Team,

In read_secret_file() of krb5-1.16.1/src/plugins/preauth/otp/otp_state.c,
When calls k5_path_join(), will store the allocated memory to filename,
later if this function returns, it does not free the memory filename points to.

The fix is to call "free(filename)" before function returns.

Could someone help to take a look?

Thanks,
Bean