Problems in crypto_drv.c

I've noticed some issues with the implementation of
crypto:rand_bytes() and the crypto driver in general.  Here
are lines
357-358 of otp_src_R11B-5/lib/crypto/c_src/crypto_drv.c:

	*rbuf = (char *)(bin = driver_alloc_binary(rlen));
	RAND_pseudo_bytes(bin->orig_bytes,rlen);

I see the following problems here:

1) The random bytes are generated with RAND_pseudo_bytes(),
which
    (unlike RAND_bytes()) isn't guaranteed to produce a
    cryptographically-strong result.  Perhaps the crypto
module should
    export both rand_bytes() and rand_pseudo_bytes(), so the
user can
    choose?

2) RAND_pseudo_bytes() can fail (returning -1), but the
driver won't
    detect this because it doesn't check the return value.

3) Most seriously, driver_alloc_binary() can return NULL
(presumably
    if malloc() fails), but the code doesn't check for this
and blindly
    dereferences the returned pointer in the next line. 
Since this is
    a linked-in driver, a NULL return will lead immediately
to the
    entire VM crashing.

Problem (3) (neglecting to check for allocation failures)
appears
repeatedly throughout crypto_drv.c.  While I admit that
equating
malloc() failure with certain death isn't too unreasonable
in many
situations, it seems unacceptable in a system reputedly able
to
provide "9 nines reliability".  I'd be interested
in hearing
explanations/opinions to the contrary.


Thanks,
Chris Stawarz
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