netdev - Re: [PATCH net 2/4] igc: Check if hardware TX timestamping is enabled earlier

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]

Message-ID: <20230531231029.36822957@kernel.org>
Date: Wed, 31 May 2023 23:10:29 -0700
From: Jakub Kicinski <kuba@...nel.org>
To: Tony Nguyen <anthony.l.nguyen@...el.com>
Cc: davem@...emloft.net, pabeni@...hat.com, edumazet@...gle.com,
 netdev@...r.kernel.org, Vinicius Costa Gomes <vinicius.gomes@...el.com>,
 sasha.neftin@...el.com, richardcochran@...il.com, Vladimir Oltean
 <vladimir.oltean@....com>, Naama Meir <naamax.meir@...ux.intel.com>
Subject: Re: [PATCH net 2/4] igc: Check if hardware TX timestamping is
 enabled earlier

On Tue, 30 May 2023 10:49:26 -0700 Tony Nguyen wrote:
> -	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)) {
> +	if (unlikely(adapter->tstamp_config.tx_type == HWTSTAMP_TX_ON &&
> +		     skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)) {
>  		/* FIXME: add support for retrieving timestamps from
>  		 * the other timer registers before skipping the
>  		 * timestamping request.
> @@ -1586,7 +1587,7 @@ static netdev_tx_t igc_xmit_frame_ring(struct sk_buff *skb,
>  		unsigned long flags;
>  
>  		spin_lock_irqsave(&adapter->ptp_tx_lock, flags);
> -		if (adapter->tstamp_config.tx_type == HWTSTAMP_TX_ON && !adapter->ptp_tx_skb) {
> +		if (!adapter->ptp_tx_skb) {

AFAICT the cancel / cleanup path is not synchronized (I mean for
accesses to adapter->tstamp_config) so this looks racy to me :(