[PATCH 5.10 182/199] net: core: devlink: use right genl user_ptr when handling port param get/set

[Greg Kroah-Hartman]

From: Oleksandr Mazur <oleksandr.ma...@plvision.eu>

commit 7e238de8283acd32c26c2bc2a50672d0ea862ff7 upstream.

Fix incorrect user_ptr dereferencing when handling port param get/set:

    idx [0] stores the 'struct devlink' pointer;
    idx [1] stores the 'struct devlink_port' pointer;

Fixes: 637989b5d77e ("devlink: Always use user_ptr[0] for devlink and simplify 
post_doit")
CC: Parav Pandit <pa...@mellanox.com>
Signed-off-by: Oleksandr Mazur <oleksandr.ma...@plvision.eu>
Signed-off-by: Vadym Kochan <vadym.koc...@plvision.eu>
Link: https://lore.kernel.org/r/20210119085333.16833-1-vadym.koc...@plvision.eu
Signed-off-by: Jakub Kicinski <k...@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 net/core/devlink.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -4134,7 +4134,7 @@ out:
 static int devlink_nl_cmd_port_param_get_doit(struct sk_buff *skb,
                                              struct genl_info *info)
 {
-       struct devlink_port *devlink_port = info->user_ptr[0];
+       struct devlink_port *devlink_port = info->user_ptr[1];
        struct devlink_param_item *param_item;
        struct sk_buff *msg;
        int err;
@@ -4163,7 +4163,7 @@ static int devlink_nl_cmd_port_param_get
 static int devlink_nl_cmd_port_param_set_doit(struct sk_buff *skb,
                                              struct genl_info *info)
 {
-       struct devlink_port *devlink_port = info->user_ptr[0];
+       struct devlink_port *devlink_port = info->user_ptr[1];
 
        return __devlink_nl_cmd_param_set_doit(devlink_port->devlink,
                                               devlink_port->index,