Re: [PATCH v2] staging: rtl8712: Fix memory leak in r8712_init_recv_priv

From: Greg KH
Date: Fri May 21 2021 - 13:02:12 EST


On Sat, May 22, 2021 at 12:25:19AM +0800, Dongliang Mu wrote:
> r871xu_dev_remove failed to call r8712_free_drv_sw() and free the
> resource (e.g., struct urb) due to the failure of firmware loading.
>
> Fix this by invoking r8712_free_drv_sw at the failure site.
>
> Reported-by: syzbot+1c46f3771695bccbdb3a@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: b4383c971bc5 ("staging: rtl8712: handle firmware load failure")
> Signed-off-by: Dongliang Mu <mudongliangabcd@xxxxxxxxx>
> ---
> v1->v2: fix the initialization of pnetdev
>
> drivers/staging/rtl8712/usb_intf.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/rtl8712/usb_intf.c b/drivers/staging/rtl8712/usb_intf.c
> index dc21e7743349..57e773464e18 100644
> --- a/drivers/staging/rtl8712/usb_intf.c
> +++ b/drivers/staging/rtl8712/usb_intf.c
> @@ -593,13 +593,14 @@ static void r871xu_dev_remove(struct usb_interface *pusb_intf)
> struct usb_device *udev = interface_to_usbdev(pusb_intf);
>
> if (pnetdev) {
> + struct net_device *newpnetdev = NULL;
> struct _adapter *padapter = netdev_priv(pnetdev);
>
> /* never exit with a firmware callback pending */
> wait_for_completion(&padapter->rtl8712_fw_ready);
> - pnetdev = usb_get_intfdata(pusb_intf);
> + newpnetdev = usb_get_intfdata(pusb_intf);

Please learn a bit more C knowledge before messing around in the kernel
tree. Between the mistake in this chunk you added, and the mistake in
the previous submission, I think you need more experience here as there
are some things you still need to learn.

Best of luck!

greg k-h