This is a note to let you know that I've just added the patch titled
gve: fix the wrong AdminQ buffer overflow check
to the 5.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
gve-fix-the-wrong-adminq-buffer-overflow-check.patch
and it can be found in the queue-5.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 02b5cc94cb7ebdd99623783f534dc0e0c06ba4e5
Author: Haiyue Wang <haiyue.wang@xxxxxxxxx>
Date: Wed Jul 14 15:34:59 2021 +0800
gve: fix the wrong AdminQ buffer overflow check
[ Upstream commit 63a9192b8fa1ea55efeba1f18fad52bb24d9bf12 ]
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@xxxxxxxxx>
Reviewed-by: Catherine Sullivan <csully@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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;
