net: wireless: bcmdhd: check packet length for event messages

Check the datalen field is less than the size of
packet received from the network.

Bug: 25306181

Signed-off-by: Patrick Tjin <pattjin@google.com>
Change-Id: I3b021d88a95bd7d4e6e0d745d2527d73487bcadc
(cherry picked from commit 10b850b7e82873a14068d24dac4fc2080d46ff76)
diff --git a/drivers/net/wireless/bcmdhd/dhd.h b/drivers/net/wireless/bcmdhd/dhd.h
index 8c3f0f6..5e33262 100644
--- a/drivers/net/wireless/bcmdhd/dhd.h
+++ b/drivers/net/wireless/bcmdhd/dhd.h
@@ -813,7 +813,7 @@
 extern int dhd_net2idx(struct dhd_info *dhd, struct net_device *net);
 extern struct net_device * dhd_idx2net(void *pub, int ifidx);
 extern int net_os_send_hang_message(struct net_device *dev);
-extern int wl_host_event(dhd_pub_t *dhd_pub, int *idx, void *pktdata,
+extern int wl_host_event(dhd_pub_t *dhd_pub, int *idx, void *pktdata, size_t pktlen,
                          wl_event_msg_t *, void **data_ptr,  void *);
 extern void wl_event_to_host_order(wl_event_msg_t * evt);
 
diff --git a/drivers/net/wireless/bcmdhd/dhd_common.c b/drivers/net/wireless/bcmdhd/dhd_common.c
index 8a6882f..201a0ac 100644
--- a/drivers/net/wireless/bcmdhd/dhd_common.c
+++ b/drivers/net/wireless/bcmdhd/dhd_common.c
@@ -109,7 +109,7 @@
 extern int dhd_socram_dump(struct dhd_bus *bus);
 #ifdef DNGL_EVENT_SUPPORT
 static void dngl_host_event_process(dhd_pub_t *dhdp, bcm_dngl_event_t *event);
-static int dngl_host_event(dhd_pub_t *dhdp, void *pktdata);
+static int dngl_host_event(dhd_pub_t *dhdp, void *pktdata, size_t pktlen);
 #endif /* DNGL_EVENT_SUPPORT */
 bool ap_cfg_running = FALSE;
 bool ap_fw_loaded = FALSE;
@@ -1380,7 +1380,7 @@
 #ifdef DNGL_EVENT_SUPPORT
 /* Check whether packet is a BRCM dngl event pkt. If it is, process event data. */
 int
-dngl_host_event(dhd_pub_t *dhdp, void *pktdata)
+dngl_host_event(dhd_pub_t *dhdp, void *pktdata, size_t pktlen)
 {
 	bcm_dngl_event_t *pvt_data = (bcm_dngl_event_t *)pktdata;
 
@@ -1391,14 +1391,14 @@
 	/* Check to see if this is a DNGL event */
 	if (ntoh16_ua((void *)&pvt_data->bcm_hdr.usr_subtype) ==
 		BCMILCP_BCM_SUBTYPE_DNGLEVENT) {
-  		dngl_host_event_process(dhdp, pvt_data);
+  		dngl_host_event_process(dhdp, pvt_data, pktlen);
 		return BCME_OK;
 	}
 	return BCME_ERROR;
 }
 
 void
-dngl_host_event_process(dhd_pub_t *dhdp, bcm_dngl_event_t *event)
+dngl_host_event_process(dhd_pub_t *dhdp, bcm_dngl_event_t *event, size_t pktlen)
 {
 	bcm_dngl_event_msg_t *dngl_event = &event->dngl_event;
 	uint8 *p = (uint8 *)(event + 1);
@@ -1407,6 +1407,9 @@
 	uint16 version = ntoh16_ua((void *)&dngl_event->version);
 
 	DHD_EVENT(("VERSION:%d, EVENT TYPE:%d, DATALEN:%d\n", version, type, datalen));
+	if (datalen > (pktlen - sizeof(bcm_event_t))) {
+		return;
+	}
 	if (version != BCM_DNGL_EVENT_MSG_VERSION) {
 		DHD_ERROR(("%s:version mismatch:%d:%d\n", __FUNCTION__,
 			version, BCM_DNGL_EVENT_MSG_VERSION));
@@ -1499,7 +1502,7 @@
 }
 #endif /* DNGL_EVENT_SUPPORT */
 
-int wl_host_event(dhd_pub_t *dhd_pub, int *ifidx, void *pktdata,
+int wl_host_event(dhd_pub_t *dhd_pub, int *ifidx, void *pktdata, size_t pktlen,
 	wl_event_msg_t *event, void **data_ptr, void *raw_event)
 {
 	/* check whether packet is a BRCM event pkt */
@@ -1512,7 +1515,7 @@
 
 #ifdef DNGL_EVENT_SUPPORT
 	/* If it is a DNGL event process it first */
-	if (dngl_host_event(dhd_pub, pktdata) == BCME_OK) {
+	if (dngl_host_event(dhd_pub, pktdata, pktlen) == BCME_OK) {
 		/* Return error purposely to prevent DNGL event being processed as BRCM event */
 		return BCME_ERROR;
 	}
@@ -1529,18 +1532,27 @@
 		return (BCME_ERROR);
 	}
 
+	if (pktlen < sizeof(bcm_event_t))
+		return (BCME_ERROR);
+
 	*data_ptr = &pvt_data[1];
 	event_data = *data_ptr;
 
-
 	/* memcpy since BRCM event pkt may be unaligned. */
 	memcpy(event, &pvt_data->event, sizeof(wl_event_msg_t));
 
 	type = ntoh32_ua((void *)&event->event_type);
 	flags = ntoh16_ua((void *)&event->flags);
 	status = ntoh32_ua((void *)&event->status);
+
 	datalen = ntoh32_ua((void *)&event->datalen);
+	if (datalen > pktlen)
+		return (BCME_ERROR);
+
 	evlen = datalen + sizeof(bcm_event_t);
+	if (evlen > pktlen) {
+		return BCME_ERROR;
+	}
 
 	/* find equivalent host index for event ifidx */
 	hostidx = dhd_ifidx2hostidx(dhd_pub->info, event->ifidx);
diff --git a/drivers/net/wireless/bcmdhd/dhd_linux.c b/drivers/net/wireless/bcmdhd/dhd_linux.c
index 3998402..7c0563a 100644
--- a/drivers/net/wireless/bcmdhd/dhd_linux.c
+++ b/drivers/net/wireless/bcmdhd/dhd_linux.c
@@ -700,7 +700,7 @@
 static int dhd_toe_set(dhd_info_t *dhd, int idx, uint32 toe_ol);
 #endif /* TOE */
 
-static int dhd_wl_host_event(dhd_info_t *dhd, int *ifidx, void *pktdata,
+static int dhd_wl_host_event(dhd_info_t *dhd, int *ifidx, void *pktdata, size_t pktlen,
                              wl_event_msg_t *event_ptr, void **data_ptr);
 #ifdef DHD_UNICAST_DHCP
 static const uint8 llc_snap_hdr[SNAP_HDR_LEN] = {0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00};
@@ -3018,6 +3018,7 @@
 #else
 			skb->mac.raw,
 #endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 22) */
+			len - 2,
 			&event,
 			&data);
 
@@ -7452,16 +7453,18 @@
 #endif /* defined(WL_WIRELESS_EXT) */
 
 static int
-dhd_wl_host_event(dhd_info_t *dhd, int *ifidx, void *pktdata,
+dhd_wl_host_event(dhd_info_t *dhd, int *ifidx, void *pktdata, size_t pktlen,
 	wl_event_msg_t *event, void **data)
 {
 	int bcmerror = 0;
 	ASSERT(dhd != NULL);
 
 #ifdef SHOW_LOGTRACE
-		bcmerror = wl_host_event(&dhd->pub, ifidx, pktdata, event, data, &dhd->event_data);
+		bcmerror = wl_host_event(&dhd->pub, ifidx, pktdata, pktlen,
+				event, data, &dhd->event_data);
 #else
-		bcmerror = wl_host_event(&dhd->pub, ifidx, pktdata, event, data, NULL);
+		bcmerror = wl_host_event(&dhd->pub, ifidx, pktdata, pktlen,
+				event, data, NULL);
 #endif /* SHOW_LOGTRACE */
 
 	if (bcmerror != BCME_OK)