gve: Fix the queue page list allocated pages count

In gve_alloc_queue_page_list(), when a page allocation fails,
qpl->num_entries will be wrong.  In this case priv->num_registered_pages
can underflow in gve_free_queue_page_list(), causing subsequent calls
to gve_alloc_queue_page_list() to fail.

Fixes: 17b7b5dff8f1 ("gve: Add transmit and receive support")
Signed-off-by: Jeroen de Borst <jeroendb@google.com>
Reviewed-by: Catherine Sullivan <csully@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index aca95f64bde80b50642ea2e3066111dcb6745a09..9b7a8db9860fc54a65c73191c0c7bd32254f7b23 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -544,7 +544,7 @@ static int gve_alloc_queue_page_list(struct gve_priv *priv, u32 id,
        }
 
        qpl->id = id;
-       qpl->num_entries = pages;
+       qpl->num_entries = 0;
        qpl->pages = kvzalloc(pages * sizeof(*qpl->pages), GFP_KERNEL);
        /* caller handles clean up */
        if (!qpl->pages)
@@ -562,6 +562,7 @@ static int gve_alloc_queue_page_list(struct gve_priv *priv, u32 id,
                /* caller handles clean up */
                if (err)
                        return -ENOMEM;
+               qpl->num_entries++;
        }
        priv->num_registered_pages += pages;