[PATCH 5.3 109/135] gve: Fix the queue page list allocated pages count

Greg Kroah-Hartman
2019-12-03T23:09:33Z

From: Jeroen de Borst <jeroendb@google.com>

[ Upstream commit a95069ecb7092d03b2ea1c39ee04514fe9627540 ]

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: f5cedc84a30d ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/google/gve/gve_main.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- 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(str
}

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(str
/* caller handles clean up */
if (err)
return -ENOMEM;
+ qpl->num_entries++;
}
priv->num_registered_pages += pages;