netdev - Re: [PATCH net] tcp: use signed arithmetic in tcp_rtx_probe0_timed

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]

Date: Fri, 7 Jun 2024 11:44:13 -0400
From: Neal Cardwell <ncardwell@...gle.com>
To: Eric Dumazet <edumazet@...gle.com>
Cc: "David S . Miller" <davem@...emloft.net>, Jakub Kicinski <kuba@...nel.org>, 
	Paolo Abeni <pabeni@...hat.com>, netdev@...r.kernel.org, eric.dumazet@...il.com, 
	Menglong Dong <imagedong@...cent.com>
Subject: Re: [PATCH net] tcp: use signed arithmetic in tcp_rtx_probe0_timed_out()

On Fri, Jun 7, 2024 at 8:56 AM Eric Dumazet <edumazet@...gle.com> wrote:
>
> Due to timer wheel implementation, a timer will usually fire
> after its schedule.
>
> For instance, for HZ=1000, a timeout between 512ms and 4s
> has a granularity of 64ms.
> For this range of values, the extra delay could be up to 63ms.
>
> For TCP, this means that tp->rcv_tstamp may be after
> inet_csk(sk)->icsk_timeout whenever the timer interrupt
> finally triggers, if one packet came during the extra delay.
>
> We need to make sure tcp_rtx_probe0_timed_out() handles this case.
>
> Fixes: e89688e3e978 ("net: tcp: fix unexcepted socket die when snd_wnd is 0")
> Signed-off-by: Eric Dumazet <edumazet@...gle.com>
> Cc: Menglong Dong <imagedong@...cent.com>
> ---

OK, makes sense. Thanks, Eric!

Acked-by: Neal Cardwell <ncardwell@...gle.com>

neal