From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailout2.w1.samsung.com (mailout2.w1.samsung.com [210.118.77.12]) (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 10ADA306D4A for ; Thu, 23 Oct 2025 11:44:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=210.118.77.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761219862; cv=none; b=FWX+x1oomOTCp8Tz6Xt9UpeGMnE7a2pDxXO+Gk8/WIyvSxVC1Eom1x/cmISMxH1gY62HIjUumN/qaG4O6b1vw9mXiuna95KTF8vHTQfD+zLqYsJv+glMlBC0K7G6VYK4Fyg0ATGr56wKNDJU90MCPnMicl+aotuLaB3FG7brhdM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761219862; c=relaxed/simple; bh=h+dc5AqFfnkmtTAZbQO+NkR9PLebd1H4BvcJw2dHSbE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:From:In-Reply-To: Content-Type:References; b=WTdgIWlMgjnU1amfyG7Px8KYRYoEasDIeEE6d6fpGaIwcvxPJrWTsXmF+IwQr0cClLA8Ga8iuGVdHHhcjB1CnQ+3MPdn69S7cBog+c/OccPhlxIum3RLgHdEuEbX5xjuWjqUx9jYH9soHKlrqpCqrbRReM9Uxqg+c4neWtHjFVs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com; spf=pass smtp.mailfrom=samsung.com; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b=aYwsPchA; arc=none smtp.client-ip=210.118.77.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=samsung.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="aYwsPchA" Received: from eucas1p1.samsung.com (unknown [182.198.249.206]) by mailout2.w1.samsung.com (KnoxPortal) with ESMTP id 20251023114418euoutp02d50099bea1bc300a587eebf41fa71058~xHCE4aXXi2455324553euoutp02K for ; Thu, 23 Oct 2025 11:44:18 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.w1.samsung.com 20251023114418euoutp02d50099bea1bc300a587eebf41fa71058~xHCE4aXXi2455324553euoutp02K DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1761219858; bh=2fURsD/TdpeT0oW0aRr7tuIshJQdrzIjM052zXlpILc=; h=Date:Subject:To:Cc:From:In-Reply-To:References:From; b=aYwsPchAgkzg8vx6Zx9On0Ol5zmYcRNq7pJA/3iWMI2MxHEsQmboZS2oUAd1Em8vw GCbsqoaDTOe7rKt+zr5549IGGelEiQxTONIcESV75u26Q1xRHzR1AtWZeJ/G4QSbE4 GAry5awAaMHBz3CpHKVZW6jdfhq3Fk8S25csgJWg= Received: from eusmtip1.samsung.com (unknown [203.254.199.221]) by eucas1p2.samsung.com (KnoxPortal) with ESMTPA id 20251023114417eucas1p2eefb194161abc6c9acbf84146a6b7201~xHCEkmvBc3032330323eucas1p2w; Thu, 23 Oct 2025 11:44:17 +0000 (GMT) Received: from [106.210.134.192] (unknown [106.210.134.192]) by eusmtip1.samsung.com (KnoxPortal) with ESMTPA id 20251023114417eusmtip1d57db1143928bedab74047ae6f135434~xHCD5EApQ2479824798eusmtip19; Thu, 23 Oct 2025 11:44:17 +0000 (GMT) Message-ID: <4efe960a-83e3-4c0b-a7e1-1d467ea94962@samsung.com> Date: Thu, 23 Oct 2025 13:44:16 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Betterbird (Windows) Subject: Re: [PATCH v3] media: videobuf2: forbid remove_bufs when legacy fileio is active To: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Tomasz Figa , Mauro Carvalho Chehab , Guennadi Liakhovetski , Benjamin Gaignard , Hans Verkuil , stable@vger.kernel.org, Shuangpeng Bai Content-Language: en-US From: Marek Szyprowski In-Reply-To: <20251023113052.1303082-1-m.szyprowski@samsung.com> Content-Transfer-Encoding: 8bit X-CMS-MailID: 20251023114417eucas1p2eefb194161abc6c9acbf84146a6b7201 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" X-RootMTR: 20251023113101eucas1p2c227985b0198d888564cab00aeb94f01 X-EPHeader: CA X-CMS-RootMailID: 20251023113101eucas1p2c227985b0198d888564cab00aeb94f01 References: <20251023113052.1303082-1-m.szyprowski@samsung.com> On 23.10.2025 13:30, Marek Szyprowski wrote: > vb2_ioctl_remove_bufs() call manipulates queue internal buffer list, > potentially overwriting some pointers used by the legacy fileio access > mode. Add a vb2_verify_memory_type() check symmetrical to > vb2_ioctl_create_bufs() to forbid that ioctl when fileio is active to > protect internal queue state between subsequent read/write calls. > > CC: stable@vger.kernel.org > Fixes: a3293a85381e ("media: v4l2: Add REMOVE_BUFS ioctl") > Reported-by: Shuangpeng Bai > Suggested-by: Benjamin Gaignard > Signed-off-by: Marek Szyprowski > --- History: v3: - moved vb2_verify_memory_type() check after (d->count == 0) check to pass v4l2  compliance v2: https://lore.kernel.org/all/20251020160121.1985354-1-m.szyprowski@samsung.com/ - dropped a change to vb2_ioctl_create_bufs(), as it is already handled   by the vb2_verify_memory_type() call - replaced queue->type check in vb2_ioctl_remove_bufs() by a call to   vb2_verify_memory_type() which covers all cases v1: https://lore.kernel.org/all/20251016111154.993949-1-m.szyprowski@samsung.com/ > drivers/media/common/videobuf2/videobuf2-v4l2.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c > index d911021c1bb0..a8a5b42a42d0 100644 > --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c > +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c > @@ -1000,13 +1000,15 @@ int vb2_ioctl_remove_bufs(struct file *file, void *priv, > struct v4l2_remove_buffers *d) > { > struct video_device *vdev = video_devdata(file); > - > - if (vdev->queue->type != d->type) > - return -EINVAL; > + int res; > > if (d->count == 0) > return 0; > > + res = vb2_verify_memory_type(vdev->queue, vdev->queue->memory, d->type); > + if (res) > + return res; > + > if (vb2_queue_is_busy(vdev->queue, file)) > return -EBUSY; > Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland