Re: [PATCH 1/2] hw/virtio/virtio-crypto: verify asym request size

[zhenwei pi]

On 12/18/25 18:43, Mauro Matteo Cascella wrote:
On Sun, Dec 14, 2025 at 10:19 AM zhenwei pi <zhenwei...@linux.dev> wrote:

The total lenght of request is limited by cryptodev config, verify it
to avoid unexpected request from guest.

CVE-2025-14876 has been assigned to this bug.

Thanks,


OK, I suggest the two patches are tagged with this CVE. This root reason 
of this issue:
- the lack of limitation from hw akcipher (this fix)
- so huge limitation (almost LONG_MAX bytes) from backend builtin driver 
(the next fix)

Fixes: 0e660a6f90a ("crypto: Introduce RSA algorithm")
Reported-by: AM 이재영 <nakamurajames...@gmail.com>
Signed-off-by: zhenwei pi <zhenwei...@linux.dev>
---
  hw/virtio/virtio-crypto.c | 7 +++++++
  1 file changed, 7 insertions(+)

diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c
index 517f2089c5..94dbf9d92d 100644
--- a/hw/virtio/virtio-crypto.c
+++ b/hw/virtio/virtio-crypto.c
@@ -767,11 +767,18 @@ virtio_crypto_handle_asym_req(VirtIOCrypto *vcrypto,
      uint32_t len;
      uint8_t *src = NULL;
      uint8_t *dst = NULL;
+    uint64_t max_len;

      asym_op_info = g_new0(CryptoDevBackendAsymOpInfo, 1);
      src_len = ldl_le_p(&req->para.src_data_len);
      dst_len = ldl_le_p(&req->para.dst_data_len);

+    max_len = src_len + dst_len;
+    if (unlikely(max_len > vcrypto->conf.max_size)) {
+        virtio_error(vdev, "virtio-crypto asym too big length");
+        goto err;
+    }
+
      if (src_len > 0) {
          src = g_malloc0(src_len);
          len = iov_to_buf(iov, out_num, 0, src, src_len);
--
2.43.0