[PATCH 2/6] brcmfmac: add subtype check for event handling in data path

[Arend van Spriel <arend.vanspriel@xxxxxxxxxxxx>]

For USB there is no separate channel being used to pass events
from firmware to the host driver and as such are passed over the
data path. In order to detect mock event messages an additional
check is needed on event subtype. This check is added conditionally
using unlikely() keyword.

Reviewed-by: Hante Meuleman <hante.meuleman@xxxxxxxxxxxx>
Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@xxxxxxxxxxxx>
Reviewed-by: Franky Lin <franky.lin@xxxxxxxxxxxx>
Signed-off-by: Arend van Spriel <arend.vanspriel@xxxxxxxxxxxx>
---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c  |  5 +++--
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h  | 16 ++++++++++++----
 .../net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c    |  2 +-
 3 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
index e772c08..a368ba6 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
@@ -519,7 +519,8 @@ void brcmf_rx_frame(struct device *dev, struct sk_buff *skb, bool handle_event)
 	} else {
 		/* Process special event packets */
 		if (handle_event)
-			brcmf_fweh_process_skb(ifp->drvr, skb);
+			brcmf_fweh_process_skb(ifp->drvr, skb,
+					       BCMILCP_SUBTYPE_VENDOR_LONG);
 
 		brcmf_netif_rx(ifp, skb);
 	}
@@ -536,7 +537,7 @@ void brcmf_rx_event(struct device *dev, struct sk_buff *skb)
 	if (brcmf_rx_hdrpull(drvr, skb, &ifp))
 		return;
 
-	brcmf_fweh_process_skb(ifp->drvr, skb);
+	brcmf_fweh_process_skb(ifp->drvr, skb, 0);
 	brcmu_pkt_buf_free_skb(skb);
 }
 
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h
index 31f3e8e..7027243 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h
@@ -211,7 +211,7 @@ enum brcmf_fweh_event_code {
  */
 #define BRCM_OUI				"\x00\x10\x18"
 #define BCMILCP_BCM_SUBTYPE_EVENT		1
-
+#define BCMILCP_SUBTYPE_VENDOR_LONG		32769
 
 /**
  * struct brcm_ethhdr - broadcom specific ether header.
@@ -334,10 +334,10 @@ void brcmf_fweh_process_event(struct brcmf_pub *drvr,
 void brcmf_fweh_p2pdev_setup(struct brcmf_if *ifp, bool ongoing);
 
 static inline void brcmf_fweh_process_skb(struct brcmf_pub *drvr,
-					  struct sk_buff *skb)
+					  struct sk_buff *skb, u16 stype)
 {
 	struct brcmf_event *event_packet;
-	u16 usr_stype;
+	u16 subtype, usr_stype;
 
 	/* only process events when protocol matches */
 	if (skb->protocol != cpu_to_be16(ETH_P_LINK_CTL))
@@ -346,8 +346,16 @@ static inline void brcmf_fweh_process_skb(struct brcmf_pub *drvr,
 	if ((skb->len + ETH_HLEN) < sizeof(*event_packet))
 		return;
 
-	/* check for BRCM oui match */
 	event_packet = (struct brcmf_event *)skb_mac_header(skb);
+
+	/* check subtype if needed */
+	if (unlikely(stype)) {
+		subtype = get_unaligned_be16(&event_packet->hdr.subtype);
+		if (subtype != stype)
+			return;
+	}
+
+	/* check for BRCM oui match */
 	if (memcmp(BRCM_OUI, &event_packet->hdr.oui[0],
 		   sizeof(event_packet->hdr.oui)))
 		return;
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c
index 4e8397a..ee922b0 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c
@@ -1116,7 +1116,7 @@ static void brcmf_msgbuf_process_event(struct brcmf_msgbuf *msgbuf, void *buf)
 
 	skb->protocol = eth_type_trans(skb, ifp->ndev);
 
-	brcmf_fweh_process_skb(ifp->drvr, skb);
+	brcmf_fweh_process_skb(ifp->drvr, skb, 0);
 
 exit:
 	brcmu_pkt_buf_free_skb(skb);
-- 
1.9.1