Re: [PATCH 1/2] usb: hso: fix error handling code of hso_create_net_device
From: Dongliang Mu <hidden>
Date: 2021-07-14 07:22:51
Also in:
lkml, netdev
On Wed, Jul 14, 2021 at 3:16 PM Dongliang Mu [off-list ref] wrote:
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].
Although there is already a patch for the above bug report, I don't think it cannot handle all kinds of errors caused in hso_create_net_device. So refactoring the error handling code is the only way to fix this issue. [1] https://syzkaller.appspot.com/text?tag=Patch&x=1188fcc6600000
quoted hunk ↗ jump to hunk
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 <redacted> --- drivers/net/usb/hso.c | 37 +++++++++++++++++++++++++++---------- 1 file changed, 27 insertions(+), 10 deletions(-)diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c index 54ef8492ca01..90fa4d9fa119 100644 --- a/drivers/net/usb/hso.c +++ b/drivers/net/usb/hso.c@@ -2495,7 +2495,9 @@ 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; + kfree(hso_dev); + usb_free_urb(hso_net->mux_bulk_tx_urb); + return NULL; } hso_net = netdev_priv(net);@@ -2508,13 +2510,13 @@ 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_get_ep; } 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_get_ep; } SET_NETDEV_DEV(net, &interface->dev); SET_NETDEV_DEVTYPE(net, &hso_type);@@ -2523,18 +2525,18 @@ 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_tx; 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_mux_bulk_tx; add_net_device(hso_dev);@@ -2542,7 +2544,7 @@ 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_register; } hso_log_port(hso_dev);@@ -2550,8 +2552,23 @@ 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_register: + unregister_netdev(net); + remove_net_device(hso_dev); +err_mux_bulk_tx: + kfree(hso_net->mux_bulk_tx_buf); + hso_net->mux_bulk_tx_buf = NULL; + 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]); + hso_net->mux_bulk_rx_buf_pool[i] = NULL; + } +err_get_ep: + free_netdev(net); + kfree(hso_dev); return NULL; } --2.25.1