[PATCH -next v3 01/13] wifi: cfg80211: pre-assign cookie for driver callbacks

[Arend van Spriel <arend.vanspriel@broadcom.com>]

Having a single place for cookie assignment and keeping that
responsibility in the cfg80211 subsystem is a logical choice as it
handles the userspace nl80211 API. add_nan_func already does this:
cfg80211 calls cfg80211_assign_cookie() before invoking the driver.
Apply the same pattern to remain_on_channel, mgmt_tx, probe_peer and
tx_control_port by pre-assigning the cookie in the nl80211 command
handlers before the rdev_* call. For tx_control_port the cookie is
only pre-assigned when the caller requests an ack (cookie pointer
non-NULL).

Drivers may still overwrite the value for now; subsequent patches will
remove per-driver cookie generation.

Assisted-by: Claude:claude-sonnet-4-6
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
 include/net/cfg80211.h | 6 ++++--
 net/wireless/nl80211.c | 5 +++++
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index dcbb0e55c32e..ee395e3a021a 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5108,7 +5108,8 @@ struct mgmt_frame_regs {
  * @tdls_oper: Perform a high-level TDLS operation (e.g. TDLS link setup).
  *
  * @probe_peer: probe a connected peer (AP: STA MAC required; STA: no MAC),
- *	must return a cookie that is later passed to cfg80211_probe_status().
+ *	must use the @cookie as provided which is later passed to
+ *	cfg80211_probe_status().
  *
  * @set_noack_map: Set the NoAck Map for the TIDs.
  *
@@ -5219,7 +5220,8 @@ struct mgmt_frame_regs {
  *     user space
  *
  * @tx_control_port: TX a control port frame (EAPoL).  The noencrypt parameter
- *	tells the driver that the frame should not be encrypted.
+ *	tells the driver that the frame should not be encrypted. When @cookie
+ *	is non-NULL it is pre-assigned by cfg80211; drivers must not modify it.
  *
  * @get_ftm_responder_stats: Retrieve FTM responder statistics, if available.
  *	Statistics should be cumulative, currently no way to reset is provided.
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 8adbef5f0442..6ad1f9cf2dda 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -14642,6 +14642,7 @@ static int nl80211_remain_on_channel(struct sk_buff *skb,
 		goto free_msg;
 	}
 
+	cookie = cfg80211_assign_cookie(rdev);
 	err = rdev_remain_on_channel(rdev, wdev, chandef.chan,
 				     duration, &cookie, rx_addr);
 
@@ -14883,6 +14884,7 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info)
 	}
 
 	params.chan = chandef.chan;
+	cookie = cfg80211_assign_cookie(rdev);
 	err = cfg80211_mlme_mgmt_tx(rdev, wdev, &params, &cookie);
 	if (err)
 		goto free_msg;
@@ -16371,6 +16373,7 @@ static int nl80211_probe_peer(struct sk_buff *skb, struct genl_info *info)
 		goto free_msg;
 	}
 
+	cookie = cfg80211_assign_cookie(rdev);
 	err = rdev_probe_peer(rdev, dev, addr, &cookie);
 	if (err)
 		goto free_msg;
@@ -18586,6 +18589,8 @@ static int nl80211_tx_control_port(struct sk_buff *skb, struct genl_info *info)
 
 	link_id = nl80211_link_id_or_invalid(info->attrs);
 
+	if (!dont_wait_for_ack)
+		cookie = cfg80211_assign_cookie(rdev);
 	err = rdev_tx_control_port(rdev, dev, buf, len,
 				   dest, cpu_to_be16(proto), noencrypt, link_id,
 				   dont_wait_for_ack ? NULL : &cookie);
-- 
2.54.0