Re: [PATCH] staging: r8188eu: add kfree() on an error path of rtw_xmit_resource_alloc()

[Greg KH <gregkh@linuxfoundation.org>]

On Sat, Sep 10, 2022 at 08:29:03AM +0200, Philipp Hortmann wrote:
> On 9/10/22 02:29, xkernel.wang@foxmail.com wrote:
> > From: Xiaoke Wang <xkernel.wang@foxmail.com>
> > 
> > In rtw_xmit_resource_alloc(), if usb_alloc_urb() fails, then the memory
> > `pxmitbuf->pallocated_buf` which is allocated by kzalloc() is not properly
> > released before returning.
> > 
> > So this patch adds kfree() on the above error path to release it. As there
> > is no proper device to test with, no runtime testing was performed.
> > 
> > Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
> > ---
> >   drivers/staging/r8188eu/core/rtw_xmit.c | 4 +++-
> >   1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/staging/r8188eu/core/rtw_xmit.c b/drivers/staging/r8188eu/core/rtw_xmit.c
> > index 67f9c05..9c39d08 100644
> > --- a/drivers/staging/r8188eu/core/rtw_xmit.c
> > +++ b/drivers/staging/r8188eu/core/rtw_xmit.c
> > @@ -44,8 +44,10 @@ static int rtw_xmit_resource_alloc(struct adapter *padapter, struct xmit_buf *px
> >   	pxmitbuf->dma_transfer_addr = 0;
> >   	pxmitbuf->pxmit_urb = usb_alloc_urb(0, GFP_KERNEL);
> > -	if (!pxmitbuf->pxmit_urb)
> > +	if (!pxmitbuf->pxmit_urb) {
> > +		kfree(pxmitbuf->pallocated_buf);
> >   		return _FAIL;
> > +	}
> >   	return _SUCCESS;
> >   }
> 
> Hi Xiaoke,
> 
> I applied your patch and tested it. That is OK.
> 
> But you excluded the change history. Usually this is not accepted by Greg.
> Reason is that what identifies the patch is the change itself. The change
> itself is the same as: "[PATCH v4] staging: r8188eu: fix potential memory
> leak in rtw_os_xmit_resource_alloc()" Even if you change the Subject,
> Description and the branch it remains the same patch for Greg.

Agreed, please fix up.

thanks,

greg k-h