cryptodev-vhost-user: fix a oob access

[Qemu-devel] [PATCH] cryptodev-vhost-user: fix a oob access

Posted by Li Qiang 5 years, 1 month ago

The 'queue_index' of create/close_session function
is from guest and can be exceed 'MAX_CRYPTO_QUEUE_NUM'.
This leads oob access. This patch avoid this.

Signed-off-by: Li Qiang <liq3ea@163.com>
---
 backends/cryptodev-vhost-user.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/backends/cryptodev-vhost-user.c b/backends/cryptodev-vhost-user.c
index 1052a5d0e9..36a40eeb4d 100644
--- a/backends/cryptodev-vhost-user.c
+++ b/backends/cryptodev-vhost-user.c
@@ -236,6 +236,8 @@ static int64_t cryptodev_vhost_user_sym_create_session(
            CryptoDevBackendSymSessionInfo *sess_info,
            uint32_t queue_index, Error **errp)
 {
+    assert(queue_index < MAX_CRYPTO_QUEUE_NUM);
+
     CryptoDevBackendClient *cc =
                    backend->conf.peers.ccs[queue_index];
     CryptoDevBackendVhost *vhost_crypto;
@@ -262,6 +264,8 @@ static int cryptodev_vhost_user_sym_close_session(
            uint64_t session_id,
            uint32_t queue_index, Error **errp)
 {
+    assert(queue_index < MAX_CRYPTO_QUEUE_NUM);
+
     CryptoDevBackendClient *cc =
                   backend->conf.peers.ccs[queue_index];
     CryptoDevBackendVhost *vhost_crypto;
-- 
2.17.1

Re: [Qemu-devel] [PATCH] cryptodev-vhost-user: fix a oob access

Posted by Gonglei (Arei) 5 years, 1 month ago

Hi,

> -----Original Message-----
> From: Li Qiang [mailto:liq3ea@163.com]
> Sent: Sunday, March 17, 2019 5:10 PM
> To: Gonglei (Arei) <arei.gonglei@huawei.com>
> Cc: qemu-devel@nongnu.org; Li Qiang <liq3ea@163.com>
> Subject: [PATCH] cryptodev-vhost-user: fix a oob access
> 
> The 'queue_index' of create/close_session function
> is from guest and can be exceed 'MAX_CRYPTO_QUEUE_NUM'.
> This leads oob access. This patch avoid this.
> 
> Signed-off-by: Li Qiang <liq3ea@163.com>
> ---
>  backends/cryptodev-vhost-user.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/backends/cryptodev-vhost-user.c b/backends/cryptodev-vhost-user.c
> index 1052a5d0e9..36a40eeb4d 100644
> --- a/backends/cryptodev-vhost-user.c
> +++ b/backends/cryptodev-vhost-user.c
> @@ -236,6 +236,8 @@ static int64_t
> cryptodev_vhost_user_sym_create_session(
>             CryptoDevBackendSymSessionInfo *sess_info,
>             uint32_t queue_index, Error **errp)
>  {
> +    assert(queue_index < MAX_CRYPTO_QUEUE_NUM);
> +
>      CryptoDevBackendClient *cc =
>                     backend->conf.peers.ccs[queue_index];
>      CryptoDevBackendVhost *vhost_crypto;
> @@ -262,6 +264,8 @@ static int cryptodev_vhost_user_sym_close_session(
>             uint64_t session_id,
>             uint32_t queue_index, Error **errp)
>  {
> +    assert(queue_index < MAX_CRYPTO_QUEUE_NUM);
> +
>      CryptoDevBackendClient *cc =
>                    backend->conf.peers.ccs[queue_index];
>      CryptoDevBackendVhost *vhost_crypto;
> --
> 2.17.1
> 

Pls add an assertion for cryptodev-builtin backend though the queue_index 
isn't used currently.

Thanks,
-Gonglei