From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (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 1B3AF33FE05 for ; Fri, 13 Feb 2026 15:01:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770994911; cv=none; b=C6OQ+DHzY0WZZoihu1mKfjaLYKoyyZfsqDQqFIq5AM006Yg1A8OIlEkJMIZNp3BLc1AajUeRGFCNr+Z6rtK5tKMOSRyQwgZrb8qWLCgL55nY63V6Opg6AtvpKLK8HMpW0aA+aCI9URNsDRBUKBq0Za4n1dDNpzJx537GO1/2P2E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770994911; c=relaxed/simple; bh=VQwymPV3vaTOOjfnGHE+QgGR8PGzLRzu8nR9Ve7U8qE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZoI+EWJtvaSYap9j/c87UmBFwqHK2Ak4yYt1cMTZAjBiN8l1jX9WUKtlUo6iFfLx3w/Q994GhdtbzccqVoFV0Mg6vREKVgyv47LKCA3QEKXgboPcBnXJvMfA58AeNUNlCTPyl4Xg4OaVQkPzi1PEKruQfAHWA/3y+3XG/H52oBs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=SDK9OhfE; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="SDK9OhfE" Received: from ideasonboard.com (93-46-82-201.ip106.fastwebnet.it [93.46.82.201]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 2C0D7CF5; Fri, 13 Feb 2026 16:00:56 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1770994856; bh=VQwymPV3vaTOOjfnGHE+QgGR8PGzLRzu8nR9Ve7U8qE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=SDK9OhfEjx3iuFrsTwZTgfrqWis9nqRegD4uablHjNQEXspIMWC3pJJkNmenP8slF 4tXnsVP0XIwnMYJ1qi0kmRiFPeCsxFaJ+LVrgXUvVJO5GVAYIDy16PoTLwGrHajZx2 XQsrdLuJoXxUjIZRq7jLHhfWPtqqxdWfza8jRLuE= Date: Fri, 13 Feb 2026 16:01:41 +0100 From: Jacopo Mondi To: Sakari Ailus Cc: linux-media@vger.kernel.org, hans@jjverkuil.nl, laurent.pinchart@ideasonboard.com, Prabhakar , Kate Hsuan , Alexander Shiyan , Dave Stevenson , Tommaso Merciai , Benjamin Mugnier , Sylvain Petinot , Christophe JAILLET , Julien Massot , Naushir Patuck , "Yan, Dongcheng" , "Cao, Bingbu" , "Qiu, Tian Shu" , Stefan Klug , Mirela Rabulea , =?utf-8?B?QW5kcsOp?= Apitzsch , Heimir Thor Sverrisson , Kieran Bingham , Mehdi Djait , Ricardo Ribalda Delgado , Hans de Goede , Jacopo Mondi , Tomi Valkeinen , David Plowman , "Yu, Ong Hock" , "Ng, Khai Wen" Subject: Re: [PATCH v2 05/14] media: v4l2-subdev: Refactor returning routes Message-ID: References: <20260211090920.1851141-1-sakari.ailus@linux.intel.com> <20260211090920.1851141-6-sakari.ailus@linux.intel.com> Precedence: bulk X-Mailing-List: linux-media@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: <20260211090920.1851141-6-sakari.ailus@linux.intel.com> Hi Sakari On Wed, Feb 11, 2026 at 11:09:11AM +0200, Sakari Ailus wrote: > Refactor returning the routes by adding a new function that essentially > does a memcopy and sets the number of the number of the routes in the > routing table. > > Signed-off-by: Sakari Ailus > --- > drivers/media/v4l2-core/v4l2-subdev.c | 40 +++++++++++++++------------ > 1 file changed, 22 insertions(+), 18 deletions(-) > > diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c > index b2105c34478e..8a433d074587 100644 > --- a/drivers/media/v4l2-core/v4l2-subdev.c > +++ b/drivers/media/v4l2-core/v4l2-subdev.c > @@ -629,6 +629,19 @@ subdev_ioctl_get_state(struct v4l2_subdev *sd, struct v4l2_subdev_fh *subdev_fh, > v4l2_subdev_get_unlocked_active_state(sd); > } > > +static void subdev_copy_fix_routes(struct v4l2_subdev_routing *routing, or just subdev_copy_routes() > + const struct v4l2_subdev_route *src, > + u32 copy_routes, u32 num_routes) > +{ > + struct v4l2_subdev_route *routes = > + (struct v4l2_subdev_route *)(uintptr_t)routing->routes; > + > + for (u32 i = 0; i < copy_routes; i++) Shouldn't this copy the min(copy_routes, num_routes) as the callers used to do ? Even better, shouldn't we just accept one 'dest' and one 'source' v4l2_subdev_routing arguments and make sure we don't copy more than min(dest->num_routes, source->num_routes) ? Having the number of routes being passed in by the caller opens the door for memory errors. > + routes[i] = src[i]; > + > + routing->num_routes = num_routes; > +} > + > static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg, > struct v4l2_subdev_state *state) > { > @@ -1000,7 +1013,6 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg, > > case VIDIOC_SUBDEV_G_ROUTING: { > struct v4l2_subdev_routing *routing = arg; > - struct v4l2_subdev_krouting *krouting; > > if (!v4l2_subdev_enable_streams_api) > return -ENOIOCTLCMD; > @@ -1013,13 +1025,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg, > > memset(routing->reserved, 0, sizeof(routing->reserved)); > > - krouting = &state->routing; > - > - memcpy((struct v4l2_subdev_route *)(uintptr_t)routing->routes, > - krouting->routes, > - min(krouting->num_routes, routing->len_routes) * > - sizeof(*krouting->routes)); > - routing->num_routes = krouting->num_routes; > + subdev_copy_fix_routes(routing, state->routing.routes, > + routing->len_routes, > + state->routing.num_routes); > > return 0; > } > @@ -1090,11 +1098,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg, > * the routing table. > */ > if (!v4l2_subdev_has_op(sd, pad, set_routing)) { > - memcpy((struct v4l2_subdev_route *)(uintptr_t)routing->routes, > - state->routing.routes, > - min(state->routing.num_routes, routing->len_routes) * > - sizeof(*state->routing.routes)); > - routing->num_routes = state->routing.num_routes; > + subdev_copy_fix_routes(routing, state->routing.routes, > + routing->len_routes, > + state->routing.num_routes); > > return 0; > } > @@ -1108,11 +1114,9 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg, > if (rval < 0) > return rval; > > - memcpy((struct v4l2_subdev_route *)(uintptr_t)routing->routes, > - state->routing.routes, > - min(state->routing.num_routes, routing->len_routes) * > - sizeof(*state->routing.routes)); > - routing->num_routes = state->routing.num_routes; > + subdev_copy_fix_routes(routing, state->routing.routes, > + routing->len_routes, > + state->routing.num_routes); > > return 0; > } > -- > 2.47.3 > >