Greg Kroah-Hartman
2020-Jun-16 15:34 UTC
[PATCH 5.7 093/163] crypto: virtio: Fix dest length calculation in __virtio_crypto_skcipher_do_req()
From: Longpeng(Mike) <longpeng2 at huawei.com>
commit d90ca42012db2863a9a30b564a2ace6016594bda upstream.
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 <arei.gonglei at huawei.com>
Cc: Herbert Xu <herbert at gondor.apana.org.au>
Cc: "Michael S. Tsirkin" <mst at redhat.com>
Cc: Jason Wang <jasowang at redhat.com>
Cc: "David S. Miller" <davem at davemloft.net>
Cc: virtualization at lists.linux-foundation.org
Cc: linux-kernel at vger.kernel.org
Cc: stable at vger.kernel.org
Signed-off-by: Longpeng(Mike) <longpeng2 at huawei.com>
Link: https://lore.kernel.org/r/20200602070501.2023-4-longpeng2 at huawei.com
Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
drivers/crypto/virtio/virtio_crypto_algs.c | 1 +
1 file changed, 1 insertion(+)
--- a/drivers/crypto/virtio/virtio_crypto_algs.c
+++ b/drivers/crypto/virtio/virtio_crypto_algs.c
@@ -402,6 +402,7 @@ __virtio_crypto_skcipher_do_req(struct v
goto free;
}
+ dst_len = min_t(unsigned int, req->cryptlen, dst_len);
pr_debug("virtio_crypto: src_len: %u, dst_len: %llu\n",
req->cryptlen, dst_len);