From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 B846E2D77F7; Tue, 21 Oct 2025 09:56:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761040594; cv=none; b=a0SuktBxNI4ZmaiiekmpeXF4sK93p06dzg6MuTZ7W/npw+nKYTZy3iFb2ancb7DUbc/pounsdyoZLJcboS/0ESgl4zFeF/Z8tO+iSLZtPU8v1Dl/xOvZngITyS1cSw391uStK1kLXIVCqK09U2fvI+Bl+vjY2eosEd9YONEyDQ4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761040594; c=relaxed/simple; bh=5Rm81nIKRtPBRA3BFntrFY6s5Mpud2dDBun1ALVD8d4=; h=Message-ID:Date:MIME-Version:From:Subject:To:Cc:References: In-Reply-To:Content-Type; b=rhyXodCVlwxPf0j7cYbfUwartUtbjuwqYJpIlD49KP7UoRgxvEF5VifTvHIEeG06LTKaqFylkYIkGZ67IpDN+j1aoumRIF3HEH/30hfNucNcPd1RSfIR2juQY0lQF12HlquGInZvS2IUD6GegKQ5qnSx+boo782koy7/+qnzyXY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TPjgrZ+Z; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TPjgrZ+Z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D772C4CEF1; Tue, 21 Oct 2025 09:56:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761040594; bh=5Rm81nIKRtPBRA3BFntrFY6s5Mpud2dDBun1ALVD8d4=; h=Date:From:Subject:To:Cc:References:In-Reply-To:From; b=TPjgrZ+ZaAcHNg/Cf8O76DLSZphZpSGUpJBhliSKiC3X6LPwVGgRCMsES/Z7RFANr VyQNhX++xTTRzpYuwcKZV2SLH5wLa3jdwUN6nZ0CjeaQz3S/wt7tVSplkR8nlXjs8q hisqHedVWgC5NWXYFUStHNnGFD0+rFPpeP8Hb5cVn2ZcpHxNby05xwj69cRLBbfda9 GTnPkNIeoopDSyihJ5Dq917ImGvkrE93AVAW49jTJmO+KCsSZrGD0dbCvQQcayzDFE VZyvERmx5R/zQSwkvs5xiz1TSBhHArsTCURc+9i8x9ovMwhNw8T0BSC5p334Hd0kCO A9o+v2Zjwsoyw== Message-ID: <9996520a-fbad-4f02-9630-7de85f04c286@kernel.org> Date: Tue, 21 Oct 2025 11:56:29 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Hans Verkuil Subject: Re: [PATCH v2] media: videobuf2: forbid remove_bufs when legacy fileio is active To: Marek Szyprowski , 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 References: <20251020160121.1985354-1-m.szyprowski@samsung.com> Content-Language: en-US, nl In-Reply-To: <20251020160121.1985354-1-m.szyprowski@samsung.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi Marek, On 20/10/2025 18:01, 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 I'll pick this up as a fix for v6.18. I think this is important enough to not wait for v6.19. Regards, Hans > --- > v2: > - 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 | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c > index d911021c1bb0..0de7490292fe 100644 > --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c > +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c > @@ -1000,9 +1000,11 @@ int vb2_ioctl_remove_bufs(struct file *file, void *priv, > struct v4l2_remove_buffers *d) > { > struct video_device *vdev = video_devdata(file); > + int res; > > - if (vdev->queue->type != d->type) > - return -EINVAL; > + res = vb2_verify_memory_type(vdev->queue, vdev->queue->memory, d->type); > + if (res) > + return res; > > if (d->count == 0) > return 0;