[PATCH 4.14 0/3] usb: hso: backport CVE-2021-37159 fix

[PATCH 4.14 0/3] usb: hso: backport CVE-2021-37159 fix

[Ovidiu Panait]

All 3 upstream commits apply cleanly:
   * 5fcfb6d0bfcd ("hso: fix bailout in error case of probe") is a support
     patch needed for context
   * a6ecfb39ba9d ("usb: hso: fix error handling code of hso_create_net_device")
     is the actual fix
   * dcb713d53e2e ("usb: hso: remove the bailout parameter") is a follow up
     cleanup commit

Dongliang Mu (2):
  usb: hso: fix error handling code of hso_create_net_device
  usb: hso: remove the bailout parameter

Oliver Neukum (1):
  hso: fix bailout in error case of probe

 drivers/net/usb/hso.c | 33 +++++++++++++++++++++++----------
 1 file changed, 23 insertions(+), 10 deletions(-)

-- 
2.25.1

[PATCH 4.14 1/3] hso: fix bailout in error case of probe

[Ovidiu Panait]

From: Oliver Neukum <oneukum@suse.com>

commit 5fcfb6d0bfcda17f0d0656e4e5b3710af2bbaae5 upstream.

The driver tries to reuse code for disconnect in case
of a failed probe.
If resources need to be freed after an error in probe, the
netdev must not be freed because it has never been registered.
Fix it by telling the helper which path we are in.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
---
 drivers/net/usb/hso.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c
index 3c3c6a8c37ee..eb2b87f186a5 100644
--- a/drivers/net/usb/hso.c
+++ b/drivers/net/usb/hso.c
@@ -2367,7 +2367,7 @@ static int remove_net_device(struct hso_device *hso_dev)
 }
 
 /* Frees our network device */
-static void hso_free_net_device(struct hso_device *hso_dev)
+static void hso_free_net_device(struct hso_device *hso_dev, bool bailout)
 {
 	int i;
 	struct hso_net *hso_net = dev2net(hso_dev);
@@ -2390,7 +2390,7 @@ static void hso_free_net_device(struct hso_device *hso_dev)
 	kfree(hso_net->mux_bulk_tx_buf);
 	hso_net->mux_bulk_tx_buf = NULL;
 
-	if (hso_net->net)
+	if (hso_net->net && !bailout)
 		free_netdev(hso_net->net);
 
 	kfree(hso_dev);
@@ -2566,7 +2566,7 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
 
 	return hso_dev;
 exit:
-	hso_free_net_device(hso_dev);
+	hso_free_net_device(hso_dev, true);
 	return NULL;
 }
 
@@ -3131,7 +3131,7 @@ static void hso_free_interface(struct usb_interface *interface)
 				rfkill_unregister(rfk);
 				rfkill_destroy(rfk);
 			}
-			hso_free_net_device(network_table[i]);
+			hso_free_net_device(network_table[i], false);
 		}
 	}
 }
-- 
2.25.1

[PATCH 4.14 2/3] usb: hso: fix error handling code of hso_create_net_device

[Ovidiu Panait]

From: Dongliang Mu <mudongliangabcd@gmail.com>

commit a6ecfb39ba9d7316057cea823b196b734f6b18ca upstream.

The current error handling code of hso_create_net_device is
hso_free_net_device, no matter which errors lead to. For example,
WARNING in hso_free_net_device [1].

Fix this by refactoring the error handling code of
hso_create_net_device by handling different errors by different code.

[1] https://syzkaller.appspot.com/bug?id=66eff8d49af1b28370ad342787413e35bbe76efe

Reported-by: syzbot+44d53c7255bb1aea22d2@syzkaller.appspotmail.com
Fixes: 5fcfb6d0bfcd ("hso: fix bailout in error case of probe")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
---
 drivers/net/usb/hso.c | 33 +++++++++++++++++++++++----------
 1 file changed, 23 insertions(+), 10 deletions(-)

diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c
index eb2b87f186a5..a47a01057e50 100644
--- a/drivers/net/usb/hso.c
+++ b/drivers/net/usb/hso.c
@@ -2510,7 +2510,7 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
 			   hso_net_init);
 	if (!net) {
 		dev_err(&interface->dev, "Unable to create ethernet device\n");
-		goto exit;
+		goto err_hso_dev;
 	}
 
 	hso_net = netdev_priv(net);
@@ -2523,13 +2523,13 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
 				      USB_DIR_IN);
 	if (!hso_net->in_endp) {
 		dev_err(&interface->dev, "Can't find BULK IN endpoint\n");
-		goto exit;
+		goto err_net;
 	}
 	hso_net->out_endp = hso_get_ep(interface, USB_ENDPOINT_XFER_BULK,
 				       USB_DIR_OUT);
 	if (!hso_net->out_endp) {
 		dev_err(&interface->dev, "Can't find BULK OUT endpoint\n");
-		goto exit;
+		goto err_net;
 	}
 	SET_NETDEV_DEV(net, &interface->dev);
 	SET_NETDEV_DEVTYPE(net, &hso_type);
@@ -2538,18 +2538,18 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
 	for (i = 0; i < MUX_BULK_RX_BUF_COUNT; i++) {
 		hso_net->mux_bulk_rx_urb_pool[i] = usb_alloc_urb(0, GFP_KERNEL);
 		if (!hso_net->mux_bulk_rx_urb_pool[i])
-			goto exit;
+			goto err_mux_bulk_rx;
 		hso_net->mux_bulk_rx_buf_pool[i] = kzalloc(MUX_BULK_RX_BUF_SIZE,
 							   GFP_KERNEL);
 		if (!hso_net->mux_bulk_rx_buf_pool[i])
-			goto exit;
+			goto err_mux_bulk_rx;
 	}
 	hso_net->mux_bulk_tx_urb = usb_alloc_urb(0, GFP_KERNEL);
 	if (!hso_net->mux_bulk_tx_urb)
-		goto exit;
+		goto err_mux_bulk_rx;
 	hso_net->mux_bulk_tx_buf = kzalloc(MUX_BULK_TX_BUF_SIZE, GFP_KERNEL);
 	if (!hso_net->mux_bulk_tx_buf)
-		goto exit;
+		goto err_free_tx_urb;
 
 	add_net_device(hso_dev);
 
@@ -2557,7 +2557,7 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
 	result = register_netdev(net);
 	if (result) {
 		dev_err(&interface->dev, "Failed to register device\n");
-		goto exit;
+		goto err_free_tx_buf;
 	}
 
 	hso_log_port(hso_dev);
@@ -2565,8 +2565,21 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
 	hso_create_rfkill(hso_dev, interface);
 
 	return hso_dev;
-exit:
-	hso_free_net_device(hso_dev, true);
+
+err_free_tx_buf:
+	remove_net_device(hso_dev);
+	kfree(hso_net->mux_bulk_tx_buf);
+err_free_tx_urb:
+	usb_free_urb(hso_net->mux_bulk_tx_urb);
+err_mux_bulk_rx:
+	for (i = 0; i < MUX_BULK_RX_BUF_COUNT; i++) {
+		usb_free_urb(hso_net->mux_bulk_rx_urb_pool[i]);
+		kfree(hso_net->mux_bulk_rx_buf_pool[i]);
+	}
+err_net:
+	free_netdev(net);
+err_hso_dev:
+	kfree(hso_dev);
 	return NULL;
 }
 
-- 
2.25.1

[PATCH 4.14 3/3] usb: hso: remove the bailout parameter

[Ovidiu Panait]

From: Dongliang Mu <mudongliangabcd@gmail.com>

commit dcb713d53e2eadf42b878c12a471e74dc6ed3145 upstream.

There are two invocation sites of hso_free_net_device. After
refactoring hso_create_net_device, this parameter is useless.
Remove the bailout in the hso_free_net_device and change the invocation
sites of this function.

Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
---
 drivers/net/usb/hso.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c
index a47a01057e50..353f300686c3 100644
--- a/drivers/net/usb/hso.c
+++ b/drivers/net/usb/hso.c
@@ -2367,7 +2367,7 @@ static int remove_net_device(struct hso_device *hso_dev)
 }
 
 /* Frees our network device */
-static void hso_free_net_device(struct hso_device *hso_dev, bool bailout)
+static void hso_free_net_device(struct hso_device *hso_dev)
 {
 	int i;
 	struct hso_net *hso_net = dev2net(hso_dev);
@@ -2390,7 +2390,7 @@ static void hso_free_net_device(struct hso_device *hso_dev, bool bailout)
 	kfree(hso_net->mux_bulk_tx_buf);
 	hso_net->mux_bulk_tx_buf = NULL;
 
-	if (hso_net->net && !bailout)
+	if (hso_net->net)
 		free_netdev(hso_net->net);
 
 	kfree(hso_dev);
@@ -3144,7 +3144,7 @@ static void hso_free_interface(struct usb_interface *interface)
 				rfkill_unregister(rfk);
 				rfkill_destroy(rfk);
 			}
-			hso_free_net_device(network_table[i], false);
+			hso_free_net_device(network_table[i]);
 		}
 	}
 }
-- 
2.25.1