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References: <20200619122300.2510533-1-antoine.tenart@bootlin.com> <20200619122300.2510533-7-antoine.tenart@bootlin.com> <20200620150045.GA2054@localhost>
Subject: Re: [PATCH net-next v3 6/8] net: phy: mscc: timestamping and PHC support
To:     Richard Cochran <richardcochran@gmail.com>
From:   Antoine Tenart <antoine.tenart@bootlin.com>
Cc:     davem@davemloft.net, andrew@lunn.ch, f.fainelli@gmail.com,
        hkallweit1@gmail.com, alexandre.belloni@bootlin.com,
        UNGLinuxDriver@microchip.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, thomas.petazzoni@bootlin.com,
        allan.nielsen@microchip.com, foss@0leil.net
Message-ID: <159283134527.1456598.6263985916427354928@kwain>
Date:   Mon, 22 Jun 2020 15:09:05 +0200
Sender: linux-kernel-owner@vger.kernel.org
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Hello Richard,

Quoting Richard Cochran (2020-06-20 17:00:45)
> On Fri, Jun 19, 2020 at 02:22:58PM +0200, Antoine Tenart wrote:
> 
> > +static void vsc85xx_dequeue_skb(struct vsc85xx_ptp *ptp)
> > +{
> > +     struct skb_shared_hwtstamps shhwtstamps;
> > +     struct vsc85xx_ts_fifo fifo;
> > +     struct sk_buff *skb;
> > +     u8 skb_sig[16], *p;
> > +     int i, len;
> > +     u32 reg;
> > +
> > +     memset(&fifo, 0, sizeof(fifo));
> > +     p = (u8 *)&fifo;
> > +
> > +     reg = vsc85xx_ts_read_csr(ptp->phydev, PROCESSOR,
> > +                               MSCC_PHY_PTP_EGR_TS_FIFO(0));
> > +     if (reg & PTP_EGR_TS_FIFO_EMPTY)
> > +             return;
> > +
> > +     *p++ = reg & 0xff;
> > +     *p++ = (reg >> 8) & 0xff;
> > +
> > +     /* Read the current FIFO item. Reading FIFO6 pops the next one. */
> > +     for (i = 1; i < 7; i++) {
> > +             reg = vsc85xx_ts_read_csr(ptp->phydev, PROCESSOR,
> > +                                       MSCC_PHY_PTP_EGR_TS_FIFO(i));
> > +             *p++ = reg & 0xff;
> > +             *p++ = (reg >> 8) & 0xff;
> > +             *p++ = (reg >> 16) & 0xff;
> > +             *p++ = (reg >> 24) & 0xff;
> > +     }
> > +
> > +     len = skb_queue_len(&ptp->tx_queue);
> > +     if (len < 1)
> > +             return;
> > +
> > +     while (len--) {
> > +             skb = __skb_dequeue(&ptp->tx_queue);
> > +             if (!skb)
> > +                     return;
> > +
> > +             /* Can't get the signature of the packet, won't ever
> > +              * be able to have one so let's dequeue the packet.
> > +              */
> > +             if (get_sig(skb, skb_sig) < 0)
> > +                     continue;
> 
> This leaks the skb.

That's right, thanks for pointing this out! I'll fix it.

Thanks,
Antoine

-- 
Antoine Ténart, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com