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 402C81EB5B; Mon, 18 Aug 2025 23:59:31 +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=1755561573; cv=none; b=k8g0qMR1AwA2NAz811Es+1QnVlovYJw+sVijgqJ8T/pn8DXLZaiBoYO+ZKji4Qy/l/Zpp8rqw+IibBoPEcG1c/Gkm6eLkUuRIyjls9I4m9KvrLE0cSwmcgHohukFxYaoQfwLMk8Xs3MkPR7l8ih8luAZ8EvaAfG8V0bx7uveooc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755561573; c=relaxed/simple; bh=kLg7XbYIsk9Q7gmAQl8rX7a/NLVyPEC6NZAox6CGTm4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Z1ctfnQFIJay2rb9B/q4/XJY2Q5evndqFui4nhaAI8p9m5hnCGCl4M230Dc1gfWQ/gD9tpSTolDwy9lgj9NcGSW/MGPZ9VXElZaMZ0u5qU6VcF9u6AE9DQJkY17vhoRfFXrTOKgYOJrUw5ljQcP60G7+Ebb188gtdVDbIPJC2ZE= 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=gFnuselq; 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="gFnuselq" Received: from pendragon.ideasonboard.com (81-175-209-231.bb.dnainternet.fi [81.175.209.231]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 8E8DDC6D; Tue, 19 Aug 2025 01:58:31 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1755561511; bh=kLg7XbYIsk9Q7gmAQl8rX7a/NLVyPEC6NZAox6CGTm4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gFnuselqMyrKeAnAzHveK3dtBfn8bkgX6bdU7LhEzHw4W/qyM/hdFy4IwOfRM0O9A 1ICJ4BzrI34GewR8tXvT/492PBFaly+cUDtihJWjq0Rv3WFUEg6ePrvBh2xI89xna+ h0b43taL5ZgECPA9Ya3tlE3OwkidnLoZRfgjjxEI= Date: Tue, 19 Aug 2025 02:59:06 +0300 From: Laurent Pinchart To: Jacopo Mondi Cc: Andy Walls , Mauro Carvalho Chehab , Hans Verkuil , Dan Carpenter , stable@vger.kernel.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 2/2] media: ivtv: Fix invalid access to file * Message-ID: <20250818235906.GC10308@pendragon.ideasonboard.com> References: <20250818-cx18-v4l2-fh-v3-0-5e2f08f3cadc@ideasonboard.com> <20250818-cx18-v4l2-fh-v3-2-5e2f08f3cadc@ideasonboard.com> Precedence: bulk X-Mailing-List: stable@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: <20250818-cx18-v4l2-fh-v3-2-5e2f08f3cadc@ideasonboard.com> Hi Jacopo, Thank you for the patch. On Mon, Aug 18, 2025 at 10:39:37PM +0200, Jacopo Mondi wrote: > Since commit 9ba9d11544f9 ("media: ivtv: Access v4l2_fh from file") > all ioctl handlers have been ported to operate on the file * first > function argument. > > The ivtv DVB layer calls ivtv_init_on_first_open() when the driver > needs to start streaming. This function calls the s_input() and > s_frequency() ioctl handlers directly, but being called from the driver > context, it doesn't have a valid file * to pass them. This causes the > ioctl handlers to deference an invalid pointer. > > Fix this by wrapping the ioctl handlers implementation in helper > functions. You may want to reword this in a similar way as proposed in 1/2. > > The ivtv_do_s_input() helper accepts a struct ivtv * as first argument, > which is easily accessible from the DVB layer as well as from the file * > argument of the ioctl handler. > > The ivtv_s_frequency() takes an ivtv_stream * instead. The stream * can > safely be accessed from the DVB layer which hard-codes it to the > IVTV_ENC_STREAM_TYPE_MPG stream type, as well as from the ioctl handler > a valid stream type is associated to each open file handle depending on > which video device node has been opened in the ivtv_open() file > operation. > > The bug has been reported by Smatch. > > Reported-by: Dan Carpenter > Closes: https://lore.kernel.org/all/aKL4OMWsESUdX8KQ@stanley.mountain/ > Fixes: 9ba9d11544f9 ("media: ivtv: Access v4l2_fh from file") > Cc: stable@vger.kernel.org > Signed-off-by: Jacopo Mondi > --- > drivers/media/pci/ivtv/ivtv-driver.c | 11 ++++------- > drivers/media/pci/ivtv/ivtv-ioctl.c | 22 +++++++++++++++++----- > drivers/media/pci/ivtv/ivtv-ioctl.h | 6 ++++-- > 3 files changed, 25 insertions(+), 14 deletions(-) > > diff --git a/drivers/media/pci/ivtv/ivtv-driver.c b/drivers/media/pci/ivtv/ivtv-driver.c > index ecc20cd89926fe2ce4e472526a6b5fc0857615dd..7e2fb98cfccf02f701ceb4484dd1d330dd1dc867 100644 > --- a/drivers/media/pci/ivtv/ivtv-driver.c > +++ b/drivers/media/pci/ivtv/ivtv-driver.c > @@ -1260,15 +1260,12 @@ static int ivtv_probe(struct pci_dev *pdev, const struct pci_device_id *pci_id) > > int ivtv_init_on_first_open(struct ivtv *itv) > { > - struct v4l2_frequency vf; > /* Needed to call ioctls later */ I'd drop the comment. > - struct ivtv_open_id fh; > + struct ivtv_stream *s = &itv->streams[IVTV_ENC_STREAM_TYPE_MPG]; > + struct v4l2_frequency vf; > int fw_retry_count = 3; > int video_input; > > - fh.itv = itv; > - fh.type = IVTV_ENC_STREAM_TYPE_MPG; > - > if (test_bit(IVTV_F_I_FAILED, &itv->i_flags)) > return -ENXIO; > > @@ -1310,13 +1307,13 @@ int ivtv_init_on_first_open(struct ivtv *itv) > > video_input = itv->active_input; > itv->active_input++; /* Force update of input */ > - ivtv_s_input(NULL, &fh, video_input); > + ivtv_do_s_input(itv, video_input); > > /* Let the VIDIOC_S_STD ioctl do all the work, keeps the code > in one place. */ > itv->std++; /* Force full standard initialization */ > itv->std_out = itv->std; > - ivtv_s_frequency(NULL, &fh, &vf); > + ivtv_do_s_frequency(s, &vf); ivtv_do_s_frequency(&itv->streams[IVTV_ENC_STREAM_TYPE_MPG], &vf); would work too. Up to you. > > if (itv->card->v4l2_capabilities & V4L2_CAP_VIDEO_OUTPUT) { > /* Turn on the TV-out: ivtv_init_mpeg_decoder() initializes > diff --git a/drivers/media/pci/ivtv/ivtv-ioctl.c b/drivers/media/pci/ivtv/ivtv-ioctl.c > index 8077a71d4850ec773caa20c3fca08f92f3117d69..dfbc842b22453868a2075935a81db7ae313ee46c 100644 > --- a/drivers/media/pci/ivtv/ivtv-ioctl.c > +++ b/drivers/media/pci/ivtv/ivtv-ioctl.c > @@ -974,9 +974,8 @@ static int ivtv_g_input(struct file *file, void *fh, unsigned int *i) > return 0; > } > > -int ivtv_s_input(struct file *file, void *fh, unsigned int inp) > +int ivtv_do_s_input(struct ivtv *itv, unsigned int inp) > { > - struct ivtv *itv = file2id(file)->itv; > v4l2_std_id std; > int i; > > @@ -1017,6 +1016,11 @@ int ivtv_s_input(struct file *file, void *fh, unsigned int inp) > return 0; > } > > +static int ivtv_s_input(struct file *file, void *fh, unsigned int inp) > +{ > + return ivtv_do_s_input(file2id(file)->itv, inp); > +} > + > static int ivtv_g_output(struct file *file, void *fh, unsigned int *i) > { > struct ivtv *itv = file2id(file)->itv; > @@ -1065,10 +1069,9 @@ static int ivtv_g_frequency(struct file *file, void *fh, struct v4l2_frequency * > return 0; > } > > -int ivtv_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *vf) > +int ivtv_do_s_frequency(struct ivtv_stream *s, const struct v4l2_frequency *vf) > { > - struct ivtv *itv = file2id(file)->itv; > - struct ivtv_stream *s = &itv->streams[file2id(file)->type]; > + struct ivtv *itv = s->itv; > > if (s->vdev.vfl_dir) > return -ENOTTY; > @@ -1082,6 +1085,15 @@ int ivtv_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *v > return 0; > } > > +static int ivtv_s_frequency(struct file *file, void *fh, > + const struct v4l2_frequency *vf) > +{ > + struct ivtv_open_id *id = file2id(file); > + struct ivtv *itv = id->itv; > + > + return ivtv_do_s_frequency(&itv->streams[id->type], vf); > +} > + > static int ivtv_g_std(struct file *file, void *fh, v4l2_std_id *std) > { > struct ivtv *itv = file2id(file)->itv; > diff --git a/drivers/media/pci/ivtv/ivtv-ioctl.h b/drivers/media/pci/ivtv/ivtv-ioctl.h > index 42c2516379fcbbd0640820ab0e3abe9bf00b57ea..dd713a6b095e5ebca45a234dd6c9a90df0928596 100644 > --- a/drivers/media/pci/ivtv/ivtv-ioctl.h > +++ b/drivers/media/pci/ivtv/ivtv-ioctl.h > @@ -17,7 +17,9 @@ int ivtv_set_speed(struct ivtv *itv, int speed); > void ivtv_set_funcs(struct video_device *vdev); > void ivtv_s_std_enc(struct ivtv *itv, v4l2_std_id std); > void ivtv_s_std_dec(struct ivtv *itv, v4l2_std_id std); > -int ivtv_s_frequency(struct file *file, void *fh, const struct v4l2_frequency *vf); > -int ivtv_s_input(struct file *file, void *fh, unsigned int inp); > + > +struct ivtv; I'd drop this, as the structure is already used above. Reviewed-by: Laurent Pinchart > +int ivtv_do_s_frequency(struct ivtv_stream *s, const struct v4l2_frequency *vf); > +int ivtv_do_s_input(struct ivtv *itv, unsigned int inp); > > #endif > -- Regards, Laurent Pinchart