[PATCH 4.19 009/306] net/mlxfw: Verify FSM error code translation doesnt exceed array size

[Greg Kroah-Hartman]

From: Eran Ben Elisha <eranbe@xxxxxxxxxxxx>

[ Upstream commit 30e9e0550bf693c94bc15827781fe42dd60be634 ]

Array mlxfw_fsm_state_err_str contains value to string translation, when
values are provided by mlxfw_dev. If value is larger than
MLXFW_FSM_STATE_ERR_MAX, return "unknown error" as expected instead of
reading an address than exceed array size.

Fixes: 410ed13cae39 ("Add the mlxfw module for Mellanox firmware flash process")
Signed-off-by: Eran Ben Elisha <eranbe@xxxxxxxxxxxx>
Acked-by: Jiri Pirko <jiri@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/mellanox/mlxfw/mlxfw_fsm.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/net/ethernet/mellanox/mlxfw/mlxfw_fsm.c
+++ b/drivers/net/ethernet/mellanox/mlxfw/mlxfw_fsm.c
@@ -86,6 +86,8 @@ retry:
 		return err;
 
 	if (fsm_state_err != MLXFW_FSM_STATE_ERR_OK) {
+		fsm_state_err = min_t(enum mlxfw_fsm_state_err,
+				      fsm_state_err, MLXFW_FSM_STATE_ERR_MAX);
 		pr_err("Firmware flash failed: %s\n",
 		       mlxfw_fsm_state_err_str[fsm_state_err]);
 		return -EINVAL;