[PATCH 6.18 52/52] wifi: atk9k: Revert "wifi: ath9k: reject short WMI command responses"

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

6.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Toke Høiland-Jørgensen <toke@toke.dk>

[ Upstream commit 90201351a862182bdabfc1ad1c97b1e1b6ed5931 ]

This reverts commit 93ce8ea70451e800601bc9444aa33043de15d67b.

Mehmet reported that the offending commit breaks his AR9271 USB adapter
which uses zero-length replies to commands that don't return a value.
Revert the whole thing to restore the functionality.

Cc: stable@vger.kernel.org # the offending commit is in 6.12.113
Reported-by: Mehmet Fide <mehmet.fide@gmail.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/wireless/ath/ath9k/wmi.c | 16 ++--------------
 drivers/net/wireless/ath/ath9k/wmi.h |  1 -
 2 files changed, 2 insertions(+), 15 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/wmi.c b/drivers/net/wireless/ath/ath9k/wmi.c
index 610717fb83f57..805ad31edba2b 100644
--- a/drivers/net/wireless/ath/ath9k/wmi.c
+++ b/drivers/net/wireless/ath/ath9k/wmi.c
@@ -206,16 +206,9 @@ static void ath9k_wmi_rsp_callback(struct wmi *wmi, struct sk_buff *skb)
 {
 	skb_pull(skb, sizeof(struct wmi_cmd_hdr));
 
-	if (wmi->cmd_rsp_buf && wmi->cmd_rsp_len) {
-		if (skb->len < wmi->cmd_rsp_len) {
-			wmi->cmd_rsp_status = -EMSGSIZE;
-			goto complete;
-		}
+	if (wmi->cmd_rsp_buf != NULL && wmi->cmd_rsp_len != 0)
 		memcpy(wmi->cmd_rsp_buf, skb->data, wmi->cmd_rsp_len);
-	}
-	wmi->cmd_rsp_status = 0;
 
-complete:
 	complete(&wmi->cmd_wait);
 }
 
@@ -307,7 +300,6 @@ static int ath9k_wmi_cmd_issue(struct wmi *wmi,
 	/* record the rsp buffer and length */
 	wmi->cmd_rsp_buf = rsp_buf;
 	wmi->cmd_rsp_len = rsp_len;
-	wmi->cmd_rsp_status = 0;
 
 	wmi->last_seq_id = wmi->tx_seq_id;
 	spin_unlock_irqrestore(&wmi->wmi_lock, flags);
@@ -364,13 +356,9 @@ int ath9k_wmi_cmd(struct wmi *wmi, enum wmi_cmd_id cmd_id,
 		return -ETIMEDOUT;
 	}
 
-	spin_lock_irqsave(&wmi->wmi_lock, flags);
-	ret = wmi->cmd_rsp_status;
-	spin_unlock_irqrestore(&wmi->wmi_lock, flags);
-
 	mutex_unlock(&wmi->op_mutex);
 
-	return ret;
+	return 0;
 
 out:
 	ath_dbg(common, WMI, "WMI failure for: %s\n", wmi_cmd_to_name(cmd_id));
diff --git a/drivers/net/wireless/ath/ath9k/wmi.h b/drivers/net/wireless/ath/ath9k/wmi.h
index 0bb9d31f1a1cc..5c3b710b8f319 100644
--- a/drivers/net/wireless/ath/ath9k/wmi.h
+++ b/drivers/net/wireless/ath/ath9k/wmi.h
@@ -157,7 +157,6 @@ struct wmi {
 	u16 tx_seq_id;
 	u8 *cmd_rsp_buf;
 	u32 cmd_rsp_len;
-	int cmd_rsp_status;
 	bool stopped;
 
 	struct list_head pending_tx_events;
-- 
2.53.0