static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm,
				     const u8 *key, unsigned int keylen)
{
	unsigned long alignmask = crypto_skcipher_alignmask(tfm);
	struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
	u8 *buffer, *alignbuffer;
	unsigned long absize;
	int ret;

	absize = keylen + alignmask;
	buffer = kmalloc(absize, GFP_ATOMIC);
	if (!buffer)
		return -ENOMEM;

	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
	memcpy(alignbuffer, key, keylen);
	ret = cipher->setkey(tfm, alignbuffer, keylen);
	kzfree(buffer);
	return ret;
}
A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.