crypto: virtio: Fix dest length calculation in __virtio_crypto_skcipher_do_req()

The src/dst length is not aligned with AES_BLOCK_SIZE(which is 16) in some
testcases in tcrypto.ko.

For example, the src/dst length of one of cts(cbc(aes))'s testcase is 17, the
crypto_virtio driver will set @src_data_len=16 but @dst_data_len=17 in this
case and get a wrong at then end.

  SRC: pp pp pp pp pp pp pp pp pp pp pp pp pp pp pp pp pp (17 bytes)
  EXP: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc pp (17 bytes)
  DST: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 00 (pollute the last bytes)
  (pp: plaintext  cc:ciphertext)

Fix this issue by limit the length of dest buffer.

Fixes: dbaf0624ffa5 ("crypto: add virtio-crypto driver")
Cc: Gonglei <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
Cc: Jason Wang <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Longpeng(Mike) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Michael S. Tsirkin <[email protected]>

0 files changed, 0 insertions, 0 deletions