netdev - Re: [PATCH net-next 06/12] net: sched: flower: handle concurrent mask insertion

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: <20190215234623.565166a4@redhat.com>
Date:   Fri, 15 Feb 2019 23:46:23 +0100
From:   Stefano Brivio <sbrivio@...hat.com>
To:     Vlad Buslov <vladbu@...lanox.com>
Cc:     netdev@...r.kernel.org, jhs@...atatu.com, xiyou.wangcong@...il.com,
        jiri@...nulli.us, davem@...emloft.net
Subject: Re: [PATCH net-next 06/12] net: sched: flower: handle concurrent
 mask insertion

On Thu, 14 Feb 2019 09:47:06 +0200
Vlad Buslov <vladbu@...lanox.com> wrote:

> @@ -1327,19 +1330,36 @@ static int fl_check_assign_mask(struct cls_fl_head *head,
>  	int ret = 0;
>  
>  	rcu_read_lock();
> -	fnew->mask = rhashtable_lookup_fast(&head->ht, mask, mask_ht_params);
> +
> +	/* Insert mask as temporary node to prevent concurrent creation of mask
> +	 * with same key. Any concurrent lookups with same key will return
> +	 * EAGAIN because mask's refcnt is zero. It is safe to insert

Nit: -EAGAIN

-- 
Stefano