linux-kernel - [PATCH 5.10 248/593] media: subdev: remove VIDIOC_DQEVENT

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Date:   Mon, 12 Jul 2021 08:06:48 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Arnd Bergmann <arnd@...db.de>,
        Laurent Pinchart <laurent.pinchart@...asonboard.com>,
        Hans Verkuil <hverkuil-cisco@...all.nl>,
        Mauro Carvalho Chehab <mchehab+huawei@...nel.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.10 248/593] media: subdev: remove VIDIOC_DQEVENT_TIME32 handling

From: Arnd Bergmann <arnd@...db.de>

[ Upstream commit 765ba251d2522e2a0daa2f0793fd0f0ce34816ec ]

Converting the VIDIOC_DQEVENT_TIME32/VIDIOC_DQEVENT32/
VIDIOC_DQEVENT32_TIME32 arguments to the canonical form is done in common
code, but for some reason I ended up adding another conversion helper to
subdev_do_ioctl() as well. I must have concluded that this does not go
through the common conversion, but it has done that since the ioctl
handler was first added.

I assume this one is harmless as there should be no way to arrive here
from user space if CONFIG_COMPAT_32BIT_TIME is set, but since it is dead
code, it should just get removed.

On a 64-bit architecture, as well as a 32-bit architecture without
CONFIG_COMPAT_32BIT_TIME, handling this command is a mistake,
and the kernel should return an error.

Fixes: 1a6c0b36dd19 ("media: v4l2-core: fix VIDIOC_DQEVENT for time64 ABI")
Signed-off-by: Arnd Bergmann <arnd@...db.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@...asonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@...all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 24 ------------------------
 1 file changed, 24 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index a7d508e74d6b..fbf0dcb313c8 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -428,30 +428,6 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 
 		return v4l2_event_dequeue(vfh, arg, file->f_flags & O_NONBLOCK);
 
-	case VIDIOC_DQEVENT_TIME32: {
-		struct v4l2_event_time32 *ev32 = arg;
-		struct v4l2_event ev = { };
-
-		if (!(sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS))
-			return -ENOIOCTLCMD;
-
-		rval = v4l2_event_dequeue(vfh, &ev, file->f_flags & O_NONBLOCK);
-
-		*ev32 = (struct v4l2_event_time32) {
-			.type		= ev.type,
-			.pending	= ev.pending,
-			.sequence	= ev.sequence,
-			.timestamp.tv_sec  = ev.timestamp.tv_sec,
-			.timestamp.tv_nsec = ev.timestamp.tv_nsec,
-			.id		= ev.id,
-		};
-
-		memcpy(&ev32->u, &ev.u, sizeof(ev.u));
-		memcpy(&ev32->reserved, &ev.reserved, sizeof(ev.reserved));
-
-		return rval;
-	}
-
 	case VIDIOC_SUBSCRIBE_EVENT:
 		return v4l2_subdev_call(sd, core, subscribe_event, vfh, arg);
 
-- 
2.30.2