[PATCH v6] wifi: mwifiex: Fix OOB and integer underflow when rx packets

[Polaris Pi]

Make sure mwifiex_process_mgmt_packet and its callers
mwifiex_process_sta_rx_packet and mwifiex_process_uap_rx_packet
not out-of-bounds access the skb->data buffer.

Fixes: 2dbaf751b1de ("mwifiex: report received management frames to cfg80211")
Signed-off-by: Polaris Pi <pinkperfect2021@xxxxxxxxx>
---
V5: Follow chromeos comments: preserve the original flow of mwifiex_process_uap_rx_packet
V6: Simplify check in mwifiex_process_uap_rx_packet
---
 drivers/net/wireless/marvell/mwifiex/sta_rx.c   |  3 ++-
 drivers/net/wireless/marvell/mwifiex/uap_txrx.c | 10 ++++++++++
 drivers/net/wireless/marvell/mwifiex/util.c     |  5 +++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/sta_rx.c b/drivers/net/wireless/marvell/mwifiex/sta_rx.c
index 13659b02ba88..88aaec645291 100644
--- a/drivers/net/wireless/marvell/mwifiex/sta_rx.c
+++ b/drivers/net/wireless/marvell/mwifiex/sta_rx.c
@@ -194,7 +194,8 @@ int mwifiex_process_sta_rx_packet(struct mwifiex_private *priv,
 
 	rx_pkt_hdr = (void *)local_rx_pd + rx_pkt_offset;
 
-	if ((rx_pkt_offset + rx_pkt_length) > (u16) skb->len) {
+	if ((rx_pkt_offset + rx_pkt_length) > (u16)skb->len ||
+	    skb->len - rx_pkt_offset < sizeof(*rx_pkt_hdr)) {
 		mwifiex_dbg(adapter, ERROR,
 			    "wrong rx packet: len=%d, rx_pkt_offset=%d, rx_pkt_length=%d\n",
 			    skb->len, rx_pkt_offset, rx_pkt_length);
diff --git a/drivers/net/wireless/marvell/mwifiex/uap_txrx.c b/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
index e495f7eaea03..f0711b73ba3e 100644
--- a/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
+++ b/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
@@ -367,6 +367,16 @@ int mwifiex_process_uap_rx_packet(struct mwifiex_private *priv,
 	rx_pkt_type = le16_to_cpu(uap_rx_pd->rx_pkt_type);
 	rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
 
+	if (le16_to_cpu(uap_rx_pd->rx_pkt_offset) + sizeof(*rx_pkt_hdr) > skb->len) {
+		mwifiex_dbg(adapter, ERROR,
+			    "wrong rx packet offset: len=%d, offset=%d\n",
+			    skb->len, le16_to_cpu(uap_rx_pd->rx_pkt_offset));
+		priv->stats.rx_dropped++;
+
+		dev_kfree_skb_any(skb);
+		return 0;
+	}
+
 	ether_addr_copy(ta, rx_pkt_hdr->eth803_hdr.h_source);
 
 	if ((le16_to_cpu(uap_rx_pd->rx_pkt_offset) +
diff --git a/drivers/net/wireless/marvell/mwifiex/util.c b/drivers/net/wireless/marvell/mwifiex/util.c
index 94c2d219835d..31e1a82883e4 100644
--- a/drivers/net/wireless/marvell/mwifiex/util.c
+++ b/drivers/net/wireless/marvell/mwifiex/util.c
@@ -399,6 +399,11 @@ mwifiex_process_mgmt_packet(struct mwifiex_private *priv,
 
 	pkt_len = le16_to_cpu(rx_pd->rx_pkt_length);
 
+	if (pkt_len < sizeof(struct ieee80211_hdr) || skb->len < pkt_len) {
+		mwifiex_dbg(priv->adapter, ERROR, "invalid rx_pkt_length");
+		return -1;
+	}
+
 	ieee_hdr = (void *)skb->data;
 	if (ieee80211_is_mgmt(ieee_hdr->frame_control)) {
 		if (mwifiex_parse_mgmt_packet(priv, (u8 *)ieee_hdr,
-- 
2.25.1