From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Xincheng Wang <22009200607@stu.xidian.edu.cn>
Cc: Jiri Slaby <jirislaby@kernel.org>,
linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org
Subject: Re: [PATCH] tty: limit TCSBRKP break duration
Date: Fri, 31 Jul 2026 17:04:40 +0200 [thread overview]
Message-ID: <2026073157-expend-unzip-cad7@gregkh> (raw)
In-Reply-To: <20260731143041.6400-1-22009200607@stu.xidian.edu.cn>
On Fri, Jul 31, 2026 at 10:30:41PM +0800, Xincheng Wang wrote:
> Hi Greg,
>
> Yes, it would still be user-visible.
>
> My concern is that tty_ioctl() first multiplies the TCSBRKP argument by
> 100 before passing it to send_break(), whose duration argument is
> unsigned int. For values above UINT_MAX / 100, the current behavior uses
> the low 32 bits of the multiplied product, which can be a duration very
> different from the requested interval.
>
> But I agree that rejecting or saturating that value would also change
> current behavior. Would you be open to a fix for this, or would you
> rather leave the path as-is?
I lost all context here :(
ANyway, keeping things as-is is always good, unless you know of a way
the current stuff is broken and you can fix it without changing any
existing users. user apis are hard...
thanks,
greg k-h
prev parent reply other threads:[~2026-07-31 15:04 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-27 5:55 [PATCH] tty: limit TCSBRKP break duration Xincheng Wang
2026-07-27 6:25 ` Greg Kroah-Hartman
2026-07-29 11:19 ` Xincheng Wang
2026-07-29 11:50 ` Greg Kroah-Hartman
2026-07-31 14:30 ` Xincheng Wang
2026-07-31 15:04 ` Greg Kroah-Hartman [this message]
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