ath6kl: wmi: prevent a shift wrapping bug in ath6kl_wmi_delete_pstream_cmd()

The "tsid" is a user controlled u8 which comes from debugfs. Values more than 15 are invalid because "active_tsids" is a 16 bit variable. If the value of "tsid" is more than 31 then that leads to a shift wrapping bug.

---
In the current code if the TSID bit isn't set it returns -ENODATA but returning -EINVAL here should be fine.

 drivers/net/wireless/ath/ath6kl/wmi.c | 5 +++++
 1 file changed, 5 insertions(+)

index a4339cca661f..dbc47702a268 100644
@@ -2639,6 +2639,11 @@ int ath6kl_wmi_delete_pstream_cmd(struct wmi *wmi, u8 if_idx, u8 traffic_class,
 		return -EINVAL;
 	}
 
+	if (tsid >= 16) {
+		ath6kl_err("invalid tsid: %d\n", tsid);
+		return -EINVAL;
+	}
+
 	skb = ath6kl_wmi_get_new_buf(sizeof(*cmd));
 	if (!skb)
 		return -ENOMEM;

2.28.0

Patch applied to ath-next branch of ath.git, thanks.

6a950755cec1 ath6kl: wmi: prevent a shift wrapping bug in ath6kl_wmi_delete_pstream_cmd()

https://patchwork.kernel.org/patch/11785193/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches