netdev - Re: [PATCH] net/hyperv: fix erroneous NETDEV_TX

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 for Android: free password hash cracker in your pocket

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

Message-ID: <4F60E9F7.4000402@candelatech.com>
Date:	Wed, 14 Mar 2012 11:56:55 -0700
From:	Ben Greear <greearb@...delatech.com>
To:	Eric Dumazet <eric.dumazet@...il.com>
CC:	David Miller <davem@...emloft.net>,
	netdev <netdev@...r.kernel.org>,
	"K. Y. Srinivasan" <kys@...rosoft.com>,
	Haiyang Zhang <haiyangz@...rosoft.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: Re: [PATCH] net/hyperv: fix erroneous NETDEV_TX_BUSY use

On 03/14/2012 11:53 AM, Eric Dumazet wrote:
> A driver start_xmit() method cannot free skb and return NETDEV_TX_BUSY,
> since caller is going to reuse freed skb.
>
> This is mostly a revert of commit bf769375c (staging: hv: fix the return
> status of netvsc_start_xmit())
>
> In fact netif_tx_stop_queue() / netif_stop_queue() is needed before
> returning NETDEV_TX_BUSY or you can trigger a ksoftirqd fatal loop.
>
> In case of memory allocation error, only safe way is to drop the packet
> and return NETDEV_TX_OK

Can you not just leave the skb alone, not bump any tx-dropped
stats, and return NETDEV_TX_BUSY?

Been a while since I looked at this code however...

Ben

-- 
Ben Greear <greearb@...delatech.com>
Candela Technologies Inc  http://www.candelatech.com

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html