2019-02-20 23:57:30

by Lorenzo Bianconi

[permalink] [raw]
Subject: [PATCH] mt76: usb: fix warning in mt76u_buf_free

From: Lorenzo Bianconi <[email protected]>

Fix following static checker warning in mt76u_buf_free:
drivers/net/wireless/mediatek/mt76/usb.c:372 mt76u_buf_free()
warn: address of 'urb->sg[i]' is non-NULL

There is no need to check sg page pointer since urb->num_sgs
has been already validated in mt76u_fill_rx_sg

Fixes: cb83585e1121 ("mt76: usb: fix possible memory leak in mt76u_buf_free")
Signed-off-by: Lorenzo Bianconi <[email protected]>
---
drivers/net/wireless/mediatek/mt76/usb.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c
index cbfddf2ebfeb..ac3da948d43a 100644
--- a/drivers/net/wireless/mediatek/mt76/usb.c
+++ b/drivers/net/wireless/mediatek/mt76/usb.c
@@ -364,16 +364,11 @@ mt76u_buf_alloc(struct mt76_dev *dev, struct mt76u_buf *buf)
void mt76u_buf_free(struct mt76u_buf *buf)
{
struct urb *urb = buf->urb;
- struct scatterlist *sg;
int i;

- for (i = 0; i < urb->num_sgs; i++) {
- sg = &urb->sg[i];
- if (!sg)
- continue;
+ for (i = 0; i < urb->num_sgs; i++)
+ skb_free_frag(sg_virt(&urb->sg[i]));

- skb_free_frag(sg_virt(sg));
- }
if (buf->buf)
skb_free_frag(buf->buf);

--
2.20.1



2019-02-21 05:10:56

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH] mt76: usb: fix warning in mt76u_buf_free

[email protected] writes:

> From: Lorenzo Bianconi <[email protected]>
>
> Fix following static checker warning in mt76u_buf_free:
> drivers/net/wireless/mediatek/mt76/usb.c:372 mt76u_buf_free()
> warn: address of 'urb->sg[i]' is non-NULL
>
> There is no need to check sg page pointer since urb->num_sgs
> has been already validated in mt76u_fill_rx_sg
>
> Fixes: cb83585e1121 ("mt76: usb: fix possible memory leak in mt76u_buf_free")
> Signed-off-by: Lorenzo Bianconi <[email protected]>

The merge window is really close, should I take this directly to
wireless-drivers-next?

BTW, Lorenzo please add your name to SMTP From line to make threading
cleaner:

From: [email protected]

--
Kalle Valo

2019-02-21 07:15:43

by Lorenzo Bianconi

[permalink] [raw]
Subject: Re: [PATCH] mt76: usb: fix warning in mt76u_buf_free

> [email protected] writes:
>
> > From: Lorenzo Bianconi <[email protected]>
> >
> > Fix following static checker warning in mt76u_buf_free:
> > drivers/net/wireless/mediatek/mt76/usb.c:372 mt76u_buf_free()
> > warn: address of 'urb->sg[i]' is non-NULL
> >
> > There is no need to check sg page pointer since urb->num_sgs
> > has been already validated in mt76u_fill_rx_sg
> >
> > Fixes: cb83585e1121 ("mt76: usb: fix possible memory leak in mt76u_buf_free")
> > Signed-off-by: Lorenzo Bianconi <[email protected]>
>
> The merge window is really close, should I take this directly to
> wireless-drivers-next?

Hi Kalle,

I think this patch can go in Felix's tree for the moment since it just fixes the warning,
the intended behaviour is to run skb_free_frag()

Regards,
Lorenzo

>
> BTW, Lorenzo please add your name to SMTP From line to make threading
> cleaner:
>
> From: [email protected]
>
> --
> Kalle Valo


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2019-02-26 09:42:03

by Felix Fietkau

[permalink] [raw]
Subject: Re: [PATCH] mt76: usb: fix warning in mt76u_buf_free

On 2019-02-21 00:57, [email protected] wrote:
> From: Lorenzo Bianconi <[email protected]>
>
> Fix following static checker warning in mt76u_buf_free:
> drivers/net/wireless/mediatek/mt76/usb.c:372 mt76u_buf_free()
> warn: address of 'urb->sg[i]' is non-NULL
>
> There is no need to check sg page pointer since urb->num_sgs
> has been already validated in mt76u_fill_rx_sg
>
> Fixes: cb83585e1121 ("mt76: usb: fix possible memory leak in mt76u_buf_free")
> Signed-off-by: Lorenzo Bianconi <[email protected]>
Applied, thanks.

- Felix