From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=62.149.156.86 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794405023; b=aMFurA/Qw3NFKqEw3p8AE44yDDaMUfqihIpiOEzXhYBaxfqsmng6dFLSbto4aYxfxvef 1K51e/pj7dmszPAutS6m2pzBiPhEqmyFEunlb5MMAOXpt8BoG5cFKqP2hZuAS8q2hZbiA L+iVlen/vqo6FSpd5BiWUpB8YnrjuSYIKvzaelxkuCEZ7+s9pkk2aQVmH9xvdeqpzupoE XNA/NT8SP+uN69hpwu8jUerL1otq0buqw2UjKbjbZeFeaEM32qrwhrLNOREpHeLa6YtAr CBWJjnzV+l7dHldXhNFnTVfgrcslgM8ZeFrLTnet6ytmA/lhqJjOA4E37oRtbj25LwA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794405023; h=DMARC-Filter:Received:DKIM-Signature:Message-ID:Date:MIME-Version: User-Agent:Subject:Content-Language:To:Cc:References:From:In-Reply-To: Content-Type:Content-Transfer-Encoding:X-CMAE-Envelope; bh=PMhvGI9ERAg7fhsMSdsC/hmF3rE9akJlGOplemvTp/I=; b=M+3I0W1szxvaGOSFmnz35o6giBk6zQWwXWMM4WFaQGTsQGYslBRaxP+gJo4adL5VR+Ea kkgNOyvEoQw0lE1xXXuD6Z1r3hnnpj1NaMDFNteon8GojiyIJtTshFy1iHcChV7BuesAE hj2hu/06fenDiBCrgCYQchb9F/euu58b0fZ0V2ANMm0VN4wX6Tl3+FgCWbr64x5sCBKea 6mnYyGDI/HV+eFCdh0ahRpwmIrpSvOGOW61TsI5Z6z6RBG5+zSwNstOZhXA0F/zdrpBsm fmXOQzT8v8sTIKhV0sqIEuUiKJxHaEaulFOnQLLaiBboqqg4V6CFHJPibqWmtcDiFcw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=enneenne.com; spf=pass smtp.mailfrom=enneenne.com; dkim=pass header.d=aruba.it header.i=@aruba.it header.a=rsa-sha256 header.s=a1 header.b=AEACPrrm; arc=none smtp.remote-ip=62.149.156.86 Received: from smtpcmd0986.aruba.it (smtpcmd0986.aruba.it [62.149.156.86]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6A70560A2603 for ; Wed, 11 Nov 2026 13:50:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 6A70560A2603 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=enneenne.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=enneenne.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=aruba.it header.i=@aruba.it header.a=rsa-sha256 header.s=a1 header.b=AEACPrrm Received: from [192.168.0.186] ([101.57.122.26]) by Aruba SMTP with ESMTPSA id R8iKxqxKS6q8sR8iKxsQjf; Wed, 11 Nov 2026 14:50:12 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=aruba.it; s=a1; t=1794405012; bh=SyFOrM7z60lMT225ZMupQKCXLeoZIrXfO4i0UdnOE0Q=; h=Date:MIME-Version:Subject:To:From:Content-Type; b=AEACPrrmJ6KLa3nyNHmLCKaPmH+S4MoNWn+D+hVVEfo+nUVoqxZCyM+git9D24wIH XpGhvyzGyNQH4s7DjvpDmXHznCROfMWdGFoyeUEkJx7eQRHAJa1AbAAS2kr0y5toUZ wfmFRSN6UeUKeegaU4tVvTUze367zE6BUv7bzwkP7B1DhqTFE9yU4uQwIkjcadTB7O VlwaQCWib4+dvfUXUkKDBKpB5hhx11ChwEnMVQWcQBgBcu9cZO204I7D8jcZRikdP8 JfPsgjHDBy9oB2ArhQT5PFoDpxs4YQMcwIIXR6ketEJV8s1zn0WFAYLYHLFsdVWmfq vQLjhZ4bsOELQ== Message-ID: Date: Wed, 11 Nov 2026 14:50:12 +0100 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] pps: reject N_PPS on pseudo-terminals Content-Language: en-US To: Hungyu Lin , Andrew Morton Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org References: <20261111132709.5959-1-dennylin0707@gmail.com> From: Rodolfo Giometti In-Reply-To: <20261111132709.5959-1-dennylin0707@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4xfN9LwweBv96Z7xTG5t868Q1CyswA0yisg7E/8KPwv2qgJp1EMdhsBCTnv20nGJkREBmK+BZOlp1LbrntA/IdcugHsVyw0UjeVeD98oUwBXxVQQ78dDru DsroarUjwb94QWwuE2qbhQxF3Z6wdLRL1cu1lZTvefaZz0LABvCXp9nzbWCPShITHEfxLBgLM6MDY0/626gSqg1OHKMVyvvz3LetIyV7lvd5rIlb/DxyY0Fr K6ofdobNN3XEruvkD9KwoA7xDSy/X2c3a7FwBopUOVY= On 11/11/2026 14:27, Hungyu Lin wrote: > Attaching N_PPS to a PTY registers a PPS source even though PTYs do not > report DCD changes. An unprivileged user can exhaust the PPS source IDs > this way, causing registration of a real PPS source to fail with > -EBUSY. > > Reject N_PPS on PTYs before allocating a source. > > Fixes: a0880df0ccde ("pps: serial clients support") > Suggested-by: Rodolfo Giometti > Signed-off-by: Hungyu Lin > --- > Changes in v2: > - Reject PTYs before registering a PPS source, as suggested by Rodolfo. > - Drop the stable Cc. > > v1: https://lore.kernel.org/r/20261107211753.75932-1-dennylin0707@gmail.com > > drivers/pps/clients/pps-ldisc.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/pps/clients/pps-ldisc.c b/drivers/pps/clients/pps-ldisc.c > index fa5660f3c4b7..83f4caced0c9 100644 > --- a/drivers/pps/clients/pps-ldisc.c > +++ b/drivers/pps/clients/pps-ldisc.c > @@ -46,6 +46,9 @@ static int pps_tty_open(struct tty_struct *tty) > struct pps_device *pps; > int ret; > > + if (drv->type == TTY_DRIVER_TYPE_PTY) > + return -EINVAL; > + > info.owner = THIS_MODULE; > info.dev = NULL; > snprintf(info.name, PPS_MAX_NAME_LEN, "%s%d", drv->driver_name, index); Acked-by: Rodolfo Giometti -- GNU/Linux Solutions e-mail: giometti@enneenne.com Linux Device Driver giometti@linux.it Embedded Systems phone: +39 349 2432127 UNIX programming