[Stable-8.0.4 54/63] virtio-crypto: verify src&dst buffer length for sym request

[Michael Tokarev]

From: zhenwei pi <pizhenwei@bytedance.com>

For symmetric algorithms, the length of ciphertext must be as same
as the plaintext.
The missing verification of the src_len and the dst_len in
virtio_crypto_sym_op_helper() may lead buffer overflow/divulged.

This patch is originally written by Yiming Tao for QEMU-SECURITY,
resend it(a few changes of error message) in qemu-devel.

Fixes: CVE-2023-3180
Fixes: 04b9b37edda("virtio-crypto: add data queue processing handler")
Cc: Gonglei <arei.gonglei@huawei.com>
Cc: Mauro Matteo Cascella <mcascell@redhat.com>
Cc: Yiming Tao <taoym@zju.edu.cn>
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Message-Id: <20230803024314.29962-2-pizhenwei@bytedance.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 9d38a8434721a6479fe03fb5afb150ca793d3980)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c
index a1d122b9aa..ccaa704530 100644
--- a/hw/virtio/virtio-crypto.c
+++ b/hw/virtio/virtio-crypto.c
@@ -635,6 +635,11 @@ virtio_crypto_sym_op_helper(VirtIODevice *vdev,
         return NULL;
     }
 
+    if (unlikely(src_len != dst_len)) {
+        virtio_error(vdev, "sym request src len is different from dst len");
+        return NULL;
+    }
+
     max_len = (uint64_t)iv_len + aad_len + src_len + dst_len + hash_result_len;
     if (unlikely(max_len > vcrypto->conf.max_size)) {
         virtio_error(vdev, "virtio-crypto too big length");
-- 
2.39.2