[PATCH v2] net/mlx4: Memcpy at slave_event should copy sizeof mlx4_eqe

From: Carol L Soto <redacted>

If the caps.eqe_size is bigger than the struct mlx4_eqe then there
is a potential for corrupting data at the master context. We can see
the message "Master failed to generate an EQE for slave: X" when the
event_eqe array wraps and we can see potential oops at the function
mlx4_GEN_EQE. Also correct a memset of cmd_eqe to use the sizeof
mlx4_eqe instead of eqe_size. 

Fixes: 08ff32352d6f ('mlx4: 64-byte CQE/EQE support')
Signed-off-by: Carol L Soto <redacted>

---
 drivers/net/ethernet/mellanox/mlx4/cmd.c | 2 +-
 drivers/net/ethernet/mellanox/mlx4/eq.c  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/cmd.c b/drivers/net/ethernet/mellanox/mlx4/cmd.c
index 0a32020..2177e56 100644
--- a/drivers/net/ethernet/mellanox/mlx4/cmd.c
+++ b/drivers/net/ethernet/mellanox/mlx4/cmd.c

@@ -2398,7 +2398,7 @@ int mlx4_multi_func_init(struct mlx4_dev *dev)
 			}
 		}
 
-		memset(&priv->mfunc.master.cmd_eqe, 0, dev->caps.eqe_size);
+		memset(&priv->mfunc.master.cmd_eqe, 0, sizeof(struct mlx4_eqe));
 		priv->mfunc.master.cmd_eqe.type = MLX4_EVENT_TYPE_CMD;
 		INIT_WORK(&priv->mfunc.master.comm_work,
 			  mlx4_master_comm_channel);

diff --git a/drivers/net/ethernet/mellanox/mlx4/eq.c b/drivers/net/ethernet/mellanox/mlx4/eq.c
index c344884..603d1c3 100644
--- a/drivers/net/ethernet/mellanox/mlx4/eq.c
+++ b/drivers/net/ethernet/mellanox/mlx4/eq.c

@@ -196,7 +196,7 @@ static void slave_event(struct mlx4_dev *dev, u8 slave, struct mlx4_eqe *eqe)
 		return;
 	}
 
-	memcpy(s_eqe, eqe, dev->caps.eqe_size - 1);
+	memcpy(s_eqe, eqe, sizeof(struct mlx4_eqe) - 1);
 	s_eqe->slave_id = slave;
 	/* ensure all information is written before setting the ownersip bit */
 	dma_wmb();

-- 
1.8.3.1

On Mon, Oct 26, 2015 at 5:15 PM,  [off-list ref] wrote:

From: Carol L Soto <redacted>

If the caps.eqe_size is bigger than the struct mlx4_eqe then there
is a potential for corrupting data at the master context. We can see
the message "Master failed to generate an EQE for slave: X" when the
event_eqe array wraps and we can see potential oops at the function
mlx4_GEN_EQE. Also correct a memset of cmd_eqe to use the sizeof
mlx4_eqe instead of eqe_size.

Fixes: 08ff32352d6f ('mlx4: 64-byte CQE/EQE support')
Signed-off-by: Carol L Soto <redacted>

Thanks Carol, I'd like to review this a bit more tomorrow and will
send it with another fix/es to net

On 10/26/2015 12:02 PM, Or Gerlitz wrote:

On Mon, Oct 26, 2015 at 5:15 PM,  [off-list ref] wrote:

quoted

From: Carol L Soto <redacted>

If the caps.eqe_size is bigger than the struct mlx4_eqe then there
is a potential for corrupting data at the master context. We can see
the message "Master failed to generate an EQE for slave: X" when the
event_eqe array wraps and we can see potential oops at the function
mlx4_GEN_EQE. Also correct a memset of cmd_eqe to use the sizeof
mlx4_eqe instead of eqe_size.

Fixes: 08ff32352d6f ('mlx4: 64-byte CQE/EQE support')
Signed-off-by: Carol L Soto <redacted>

Thanks Carol, I'd like to review this a bit more tomorrow and will
send it with another fix/es to net

Sure thanks.