[PATCH AUTOSEL 4.18 060/100] net/mlx5: E-Switch, Fix out of bound access when setting vport rate

[Sasha Levin]

From: Eran Ben Elisha <eranbe@xxxxxxxxxxxx>

[ Upstream commit 11aa5800ed66ed0415b7509f02881c76417d212a ]

The code that deals with eswitch vport bw guarantee was going beyond the
eswitch vport array limit, fix that.  This was pointed out by the kernel
address sanitizer (KASAN).

The error from KASAN log:
[2018-09-15 15:04:45] BUG: KASAN: slab-out-of-bounds in
mlx5_eswitch_set_vport_rate+0x8c1/0xae0 [mlx5_core]

Fixes: c9497c98901c ("net/mlx5: Add support for setting VF min rate")
Signed-off-by: Eran Ben Elisha <eranbe@xxxxxxxxxxxx>
Reviewed-by: Or Gerlitz <ogerlitz@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/mellanox/mlx5/core/eswitch.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
index 40dba9e8af92..69f356f5f8f5 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
@@ -2000,7 +2000,7 @@ static u32 calculate_vports_min_rate_divider(struct mlx5_eswitch *esw)
 	u32 max_guarantee = 0;
 	int i;
 
-	for (i = 0; i <= esw->total_vports; i++) {
+	for (i = 0; i < esw->total_vports; i++) {
 		evport = &esw->vports[i];
 		if (!evport->enabled || evport->info.min_rate < max_guarantee)
 			continue;
@@ -2020,7 +2020,7 @@ static int normalize_vports_min_rate(struct mlx5_eswitch *esw, u32 divider)
 	int err;
 	int i;
 
-	for (i = 0; i <= esw->total_vports; i++) {
+	for (i = 0; i < esw->total_vports; i++) {
 		evport = &esw->vports[i];
 		if (!evport->enabled)
 			continue;
-- 
2.17.1