lkml.org 
[lkml]   [2021]   [Jul]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v1] gve: fix the wrong AdminQ buffer overflow check
On Wed, Jul 14, 2021 at 12:58 AM Haiyue Wang <haiyue.wang@intel.com> wrote:
>
> The 'tail' pointer is also free-running count, so it needs to be masked
> as 'adminq_prod_cnt' does, to become an index value of AdminQ buffer.
>
> Fixes: 5cdad90de62c ("gve: Batch AQ commands for creating and destroying queues.")
> Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>

Reviewed-by: Catherine Sullivan <csully@google.com>

> ---
> drivers/net/ethernet/google/gve/gve_adminq.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/google/gve/gve_adminq.c b/drivers/net/ethernet/google/gve/gve_adminq.c
> index 5bb56b454541..f089d33dd48e 100644
> --- a/drivers/net/ethernet/google/gve/gve_adminq.c
> +++ b/drivers/net/ethernet/google/gve/gve_adminq.c
> @@ -322,7 +322,8 @@ static int gve_adminq_issue_cmd(struct gve_priv *priv,
> tail = ioread32be(&priv->reg_bar0->adminq_event_counter);
>
> // Check if next command will overflow the buffer.
> - if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) == tail) {
> + if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) ==
> + (tail & priv->adminq_mask)) {
> int err;
>
> // Flush existing commands to make room.
> @@ -332,7 +333,8 @@ static int gve_adminq_issue_cmd(struct gve_priv *priv,
>
> // Retry.
> tail = ioread32be(&priv->reg_bar0->adminq_event_counter);
> - if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) == tail) {
> + if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) ==
> + (tail & priv->adminq_mask)) {
> // This should never happen. We just flushed the
> // command queue so there should be enough space.
> return -ENOMEM;
> --
> 2.32.0
>

Thanks!

\
 
 \ /
  Last update: 2021-07-15 00:47    [W:0.052 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site