[PATCH v8] wifi: mwifiex: Fix OOB and integer underflow when rx packets

[PATCH v8] wifi: mwifiex: Fix OOB and integer underflow when rx packets

[Polaris Pi]

Make sure mwifiex_process_mgmt_packet,
mwifiex_process_sta_rx_packet and mwifiex_process_uap_rx_packet,
mwifiex_uap_queue_bridged_pkt and mwifiex_process_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@gmail.com>
---
V5: Follow chromeos comments: preserve the original flow of mwifiex_process_uap_rx_packet
V6: Simplify check in mwifiex_process_uap_rx_packet
V7: Fix drop packets issue when auotest V6, now pass manual and auto tests
V8: Fix missing return after free skb
---
 drivers/net/wireless/marvell/mwifiex/sta_rx.c | 12 ++++++++++-
 .../net/wireless/marvell/mwifiex/uap_txrx.c   | 20 +++++++++++++++++++
 drivers/net/wireless/marvell/mwifiex/util.c   | 10 +++++++---
 3 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/sta_rx.c b/drivers/net/wireless/marvell/mwifiex/sta_rx.c
index 13659b02ba88..65420ad67416 100644
--- a/drivers/net/wireless/marvell/mwifiex/sta_rx.c
+++ b/drivers/net/wireless/marvell/mwifiex/sta_rx.c
@@ -86,6 +86,15 @@ int mwifiex_process_rx_packet(struct mwifiex_private *priv,
 	rx_pkt_len = le16_to_cpu(local_rx_pd->rx_pkt_length);
 	rx_pkt_hdr = (void *)local_rx_pd + rx_pkt_off;
 
+	if (sizeof(*rx_pkt_hdr) + rx_pkt_off > skb->len) {
+		mwifiex_dbg(priv->adapter, ERROR,
+			    "wrong rx packet offset: len=%d, rx_pkt_off=%d\n",
+			    skb->len, rx_pkt_off);
+		priv->stats.rx_dropped++;
+		dev_kfree_skb_any(skb);
+		return -1;
+	}
+
 	if ((!memcmp(&rx_pkt_hdr->rfc1042_hdr, bridge_tunnel_header,
 		     sizeof(bridge_tunnel_header))) ||
 	    (!memcmp(&rx_pkt_hdr->rfc1042_hdr, rfc1042_header,
@@ -194,7 +203,8 @@ 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) > skb->len ||
+	    sizeof(rx_pkt_hdr->eth803_hdr) + rx_pkt_offset > skb->len) {
 		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..c1b8d41dd753 100644
--- a/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
+++ b/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
@@ -103,6 +103,16 @@ static void mwifiex_uap_queue_bridged_pkt(struct mwifiex_private *priv,
 		return;
 	}
 
+	if (sizeof(*rx_pkt_hdr) +
+	    le16_to_cpu(uap_rx_pd->rx_pkt_offset) > skb->len) {
+		mwifiex_dbg(adapter, ERROR,
+			    "wrong rx packet offset: len=%d,rx_pkt_offset=%d\n",
+			    skb->len, le16_to_cpu(uap_rx_pd->rx_pkt_offset));
+		priv->stats.rx_dropped++;
+		dev_kfree_skb_any(skb);
+		return;
+	}
+
 	if ((!memcmp(&rx_pkt_hdr->rfc1042_hdr, bridge_tunnel_header,
 		     sizeof(bridge_tunnel_header))) ||
 	    (!memcmp(&rx_pkt_hdr->rfc1042_hdr, rfc1042_header,
@@ -367,6 +377,16 @@ 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->eth803_hdr) > skb->len) {
+		mwifiex_dbg(adapter, ERROR,
+			    "wrong rx packet for struct ethhdr: 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..745b1d925b21 100644
--- a/drivers/net/wireless/marvell/mwifiex/util.c
+++ b/drivers/net/wireless/marvell/mwifiex/util.c
@@ -393,11 +393,15 @@ mwifiex_process_mgmt_packet(struct mwifiex_private *priv,
 	}
 
 	rx_pd = (struct rxpd *)skb->data;
+	pkt_len = le16_to_cpu(rx_pd->rx_pkt_length);
+	if (pkt_len < sizeof(struct ieee80211_hdr) + sizeof(pkt_len)) {
+		mwifiex_dbg(priv->adapter, ERROR, "invalid rx_pkt_length");
+		return -1;
+	}
 
 	skb_pull(skb, le16_to_cpu(rx_pd->rx_pkt_offset));
 	skb_pull(skb, sizeof(pkt_len));
-
-	pkt_len = le16_to_cpu(rx_pd->rx_pkt_length);
+	pkt_len -= sizeof(pkt_len);
 
 	ieee_hdr = (void *)skb->data;
 	if (ieee80211_is_mgmt(ieee_hdr->frame_control)) {
@@ -410,7 +414,7 @@ mwifiex_process_mgmt_packet(struct mwifiex_private *priv,
 		skb->data + sizeof(struct ieee80211_hdr),
 		pkt_len - sizeof(struct ieee80211_hdr));
 
-	pkt_len -= ETH_ALEN + sizeof(pkt_len);
+	pkt_len -= ETH_ALEN;
 	rx_pd->rx_pkt_length = cpu_to_le16(pkt_len);
 
 	cfg80211_rx_mgmt(&priv->wdev, priv->roc_cfg.chan.center_freq,
-- 
2.25.1

Re: [PATCH v8] wifi: mwifiex: Fix OOB and integer underflow when rx packets

[Johannes Berg]

On Wed, 2023-08-09 at 21:58 +0000, Polaris Pi wrote:
> Make sure mwifiex_process_mgmt_packet,
> mwifiex_process_sta_rx_packet and mwifiex_process_uap_rx_packet,
> mwifiex_uap_queue_bridged_pkt and mwifiex_process_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@gmail.com>
> ---
> V5: Follow chromeos comments: preserve the original flow of mwifiex_process_uap_rx_packet
> V6: Simplify check in mwifiex_process_uap_rx_packet
> V7: Fix drop packets issue when auotest V6, now pass manual and auto tests
> V8: Fix missing return after free skb
> 

Arguably, as Brian also said, that missing return is completely
unrelated and should perhaps be a separate commit?

johannes

[PATCH] wifi: mwifiex: Fix missed return in oob checks failed path

[Polaris Pi]

Add missed return in mwifiex_uap_queue_bridged_pkt and
mwifiex_process_rx_packet.

Fixes: 119585281617 ("wifi: mwifiex: Fix OOB and integer underflow when rx packets")
Signed-off-by: Polaris Pi <pinkperfect2021@gmail.com>
---
 drivers/net/wireless/marvell/mwifiex/sta_rx.c   | 1 +
 drivers/net/wireless/marvell/mwifiex/uap_txrx.c | 1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/net/wireless/marvell/mwifiex/sta_rx.c b/drivers/net/wireless/marvell/mwifiex/sta_rx.c
index f2899d53a43f..65420ad67416 100644
--- a/drivers/net/wireless/marvell/mwifiex/sta_rx.c
+++ b/drivers/net/wireless/marvell/mwifiex/sta_rx.c
@@ -92,6 +92,7 @@ int mwifiex_process_rx_packet(struct mwifiex_private *priv,
 			    skb->len, rx_pkt_off);
 		priv->stats.rx_dropped++;
 		dev_kfree_skb_any(skb);
+		return -1;
 	}
 
 	if ((!memcmp(&rx_pkt_hdr->rfc1042_hdr, bridge_tunnel_header,
diff --git a/drivers/net/wireless/marvell/mwifiex/uap_txrx.c b/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
index 04ff051f5d18..c1b8d41dd753 100644
--- a/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
+++ b/drivers/net/wireless/marvell/mwifiex/uap_txrx.c
@@ -110,6 +110,7 @@ static void mwifiex_uap_queue_bridged_pkt(struct mwifiex_private *priv,
 			    skb->len, le16_to_cpu(uap_rx_pd->rx_pkt_offset));
 		priv->stats.rx_dropped++;
 		dev_kfree_skb_any(skb);
+		return;
 	}
 
 	if ((!memcmp(&rx_pkt_hdr->rfc1042_hdr, bridge_tunnel_header,
-- 
2.25.1

Re: [PATCH] wifi: mwifiex: Fix missed return in oob checks failed path

[Brian Norris]

On Thu, Aug 10, 2023 at 08:39:11AM +0000, Polaris Pi wrote:
> Add missed return in mwifiex_uap_queue_bridged_pkt and
> mwifiex_process_rx_packet.
> 
> Fixes: 119585281617 ("wifi: mwifiex: Fix OOB and integer underflow when rx packets")
> Signed-off-by: Polaris Pi <pinkperfect2021@gmail.com>

Reported-by: Dmitry Antipov <dmantipov@yandex.ru>

And:

Acked-by: Brian Norris <briannorris@chromium.org>

Re: [PATCH v8] wifi: mwifiex: Fix OOB and integer underflow when rx packets

[Brian Norris]

On Thu, Aug 10, 2023 at 09:32:57AM +0200, Johannes Berg wrote:
> On Wed, 2023-08-09 at 21:58 +0000, Polaris Pi wrote:
> > Make sure mwifiex_process_mgmt_packet,
> > mwifiex_process_sta_rx_packet and mwifiex_process_uap_rx_packet,
> > mwifiex_uap_queue_bridged_pkt and mwifiex_process_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@gmail.com>
> > ---
> > V5: Follow chromeos comments: preserve the original flow of mwifiex_process_uap_rx_packet
> > V6: Simplify check in mwifiex_process_uap_rx_packet
> > V7: Fix drop packets issue when auotest V6, now pass manual and auto tests
> > V8: Fix missing return after free skb
> > 
> 
> Arguably, as Brian also said, that missing return is completely
> unrelated and should perhaps be a separate commit?

I think the key here is that Polaris's buggy patch has already been
applied, so this v8 doesn't really work. He has since submitted a proper
fixup patch that applies appropriately, and I've Ack'd that.

Brian

Re: [PATCH v8] wifi: mwifiex: Fix OOB and integer underflow when rx packets

[Johannes Berg]

On Thu, 2023-08-10 at 16:54 -0700, Brian Norris wrote:
> On Thu, Aug 10, 2023 at 09:32:57AM +0200, Johannes Berg wrote:
> > On Wed, 2023-08-09 at 21:58 +0000, Polaris Pi wrote:
> > > Make sure mwifiex_process_mgmt_packet,
> > > mwifiex_process_sta_rx_packet and mwifiex_process_uap_rx_packet,
> > > mwifiex_uap_queue_bridged_pkt and mwifiex_process_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@gmail.com>
> > > ---
> > > V5: Follow chromeos comments: preserve the original flow of mwifiex_process_uap_rx_packet
> > > V6: Simplify check in mwifiex_process_uap_rx_packet
> > > V7: Fix drop packets issue when auotest V6, now pass manual and auto tests
> > > V8: Fix missing return after free skb
> > > 
> > 
> > Arguably, as Brian also said, that missing return is completely
> > unrelated and should perhaps be a separate commit?
> 
> I think the key here is that Polaris's buggy patch has already been
> applied, so this v8 doesn't really work. He has since submitted a proper
> fixup patch that applies appropriately, and I've Ack'd that.
> 

Right, sorry, I missed that, was looking only at wireless, not wireless-
next.

Thanks all, I'll leave the -next patches for Kalle though :)

johannes

Re: wifi: mwifiex: Fix missed return in oob checks failed path

[Kalle Valo]

Polaris Pi <pinkperfect2021@gmail.com> wrote:

> Add missed return in mwifiex_uap_queue_bridged_pkt() and
> mwifiex_process_rx_packet().
> 
> Fixes: 119585281617 ("wifi: mwifiex: Fix OOB and integer underflow when rx packets")
> Signed-off-by: Polaris Pi <pinkperfect2021@gmail.com>
> Reported-by: Dmitry Antipov <dmantipov@yandex.ru>
> Acked-by: Brian Norris <briannorris@chromium.org>

Patch applied to wireless-next.git, thanks.

2785851c627f wifi: mwifiex: Fix missed return in oob checks failed path

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20230810083911.3725248-1-pinkperfect2021@gmail.com/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches