On Wed, Jul 14, 2021 at 3:16 PM Dongliang Mu <mudongliangabcd@xxxxxxxxx> 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 > > 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@xxxxxxxxxxxxxxxxxxxxxxxxx > Fixes: 5fcfb6d0bfcd ("hso: fix bailout in error case of probe") > Signed-off-by: Dongliang Mu <mudongliangabcd@xxxxxxxxx> > --- > 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 >
