smbencrypt() points a scatterlist to the stack, which is breaks if
Fix it by switching to crypto_cipher_encrypt_one(). The new code
should be considerably faster as an added benefit.
This code is nearly identical to some code that Eric Biggers
Cc: stable@xxxxxxxxxxxxxxx # 4.9 only
Reported-by: Eric Biggers <ebiggers3@xxxxxxxxx>
Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>