Subject: [V2 net 11/11] net/mlx5e: TC, Fix slab-out-of-bounds in parse_tc_actions

From: Saeed Mahameed <[email-masked]>
Date: Sat, 5 Nov 2022 00:10:28 -0700

From: Roi Dayan <[email-masked]>

esw_attr is only allocated if namespace is fdb.

BUG: KASAN: slab-out-of-bounds in parse_tc_actions+0xdc6/0x10e0 [mlx5_core]
Write of size 4 at addr ffff88815f185b04 by task tc/2135

CPU: 5 PID: 2135 Comm: tc Not tainted 6.1.0-rc2+ #2
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x57/0x7d
 print_report+0x170/0x471
 ? parse_tc_actions+0xdc6/0x10e0 [mlx5_core]
 kasan_report+0xbc/0xf0
 ? parse_tc_actions+0xdc6/0x10e0 [mlx5_core]
 parse_tc_actions+0xdc6/0x10e0 [mlx5_core]

Fixes: 94d651739e17 ("net/mlx5e: TC, Fix cloned flow attr instance dests are not zeroed")
Signed-off-by: Roi Dayan <[email-masked]>
Reviewed-by: Maor Dickman <[email-masked]>
Signed-off-by: Saeed Mahameed <[email-masked]>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_tc.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
index 372dfb89e396..5a6aa61ec82a 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
@@ -3633,10 +3633,14 @@ mlx5e_clone_flow_attr_for_post_act(struct mlx5_flow_attr *attr,
 	attr2->action = 0;
 	attr2->flags = 0;
 	attr2->parse_attr = parse_attr;
-	attr2->esw_attr->out_count = 0;
-	attr2->esw_attr->split_count = 0;
 	attr2->dest_chain = 0;
 	attr2->dest_ft = NULL;
+
+	if (ns_type == MLX5_FLOW_NAMESPACE_FDB) {
+		attr2->esw_attr->out_count = 0;
+		attr2->esw_attr->split_count = 0;
+	}
+
 	return attr2;
 }
 
-- 
2.38.1