netdev - Re: [PATCH] net: korina: remove busy skb free

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 14 Dec 2020 11:03:12 +0100
From:   Julian Wiedmann <jwi@...ux.ibm.com>
To:     Vincent Stehlé <vincent.stehle@...oste.net>,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     "David S . Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Florian Fainelli <florian.fainelli@...ecomint.eu>
Subject: Re: [PATCH] net: korina: remove busy skb free

On 13.12.20 18:20, Vincent Stehlé wrote:
> The ndo_start_xmit() method must not attempt to free the skb to transmit
> when returning NETDEV_TX_BUSY. Fix the korina_send_packet() function
> accordingly.
> 
> Fixes: ef11291bcd5f ("Add support the Korina (IDT RC32434) Ethernet MAC")
> Signed-off-by: Vincent Stehlé <vincent.stehle@...oste.net>
> Cc: David S. Miller <davem@...emloft.net>
> Cc: Jakub Kicinski <kuba@...nel.org>
> Cc: Florian Fainelli <florian.fainelli@...ecomint.eu>
> ---
>  drivers/net/ethernet/korina.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/korina.c b/drivers/net/ethernet/korina.c
> index bf48f0ded9c7d..9d84191de6824 100644
> --- a/drivers/net/ethernet/korina.c
> +++ b/drivers/net/ethernet/korina.c
> @@ -216,7 +216,6 @@ static int korina_send_packet(struct sk_buff *skb, struct net_device *dev)
>  			netif_stop_queue(dev);
>  		else {
>  			dev->stats.tx_dropped++;
> -			dev_kfree_skb_any(skb);
>  			spin_unlock_irqrestore(&lp->lock, flags);
>  
>  			return NETDEV_TX_BUSY;
> 

As this skb is returned to the stack (and not dropped), the tx_dropped
statistics increment looks bogus too.