From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 48A9A163 for ; Wed, 14 Jan 2026 10:27:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768386431; cv=none; b=Z+OVWRqP9i0Kh2QJqFDjWXCBf6FuXT76qeIHxsA32Zkw1YwrvtKnXRG8vEBi6MTty4X9dNQTdemo0S4wbs1Bqa98DJlji0OWUHFvtzWu7aYZRFChRGt+odYflu3wN09P931xw8rN63dS8LqXUw8JdWCMxqNGvE4i1MZc6jgaHL8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768386431; c=relaxed/simple; bh=RUMfVura3/eXw0ZnXPtoe/GJYyeXJ5lVATjElpkcsyI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VHzr9YTCdpJUgc1qWoej26lwrPoQbzcfohUDatgURvIWdi0Aw2xuqMonckLsPKnKW6NzJdmxMhxwdXMOoN2C4SgQ1cKJ9ocg2+2F3p34ZP04Z4WE7FHxaOSqqgvhGNjGmLwGSOyqjSHjT4bGepqfdhjEHxyrJDp1vMN9jGPTS+4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1vfy5f-0002sr-Tn; Wed, 14 Jan 2026 11:27:03 +0100 Received: from pty.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::c5]) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vfy5g-000ZY7-0z; Wed, 14 Jan 2026 11:27:03 +0100 Received: from ore by pty.whiteo.stw.pengutronix.de with local (Exim 4.96) (envelope-from ) id 1vfy5f-00BgzC-1l; Wed, 14 Jan 2026 11:27:03 +0100 Date: Wed, 14 Jan 2026 11:27:03 +0100 From: Oleksij Rempel To: Marc Kleine-Budde Cc: Tetsuo Handa , Robin van der Gracht , kernel@pengutronix.de, Oliver Hartkopp , linux-can@vger.kernel.org, Network Development Subject: Re: [PATCH] can: j1939: deactivate session upon receiving the second rts Message-ID: References: <4b1fbe9d-5ca2-41e9-b252-1304cc7c215a@I-love.SAKURA.ne.jp> <20260114-sticky-inescapable-spoonbill-52932b-mkl@pengutronix.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260114-sticky-inescapable-spoonbill-52932b-mkl@pengutronix.de> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org On Wed, Jan 14, 2026 at 11:22:34AM +0100, Marc Kleine-Budde wrote: > On 14.01.2026 00:28:47, Tetsuo Handa wrote: > > Since j1939_session_deactivate_activate_next() in j1939_tp_rxtimer() is > > called only when the timer is enabled, we need to call > > j1939_session_deactivate_activate_next() if we cancelled the timer. > > Otherwise, refcount for j1939_session leaks, which will later appear as > > > > unregister_netdevice: waiting for vcan0 to become free. Usage count = 2. > > > > problem. > > > > Reported-by: syzbot > > Closes: https://syzkaller.appspot.com/bug?extid=881d65229ca4f9ae8c84 > > Signed-off-by: Tetsuo Handa > > Can you provide a Fixes tag? No need to resend. I'll add it while > applying. Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |