Commit 577c89b0 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Mauro Carvalho Chehab
Browse files

media: v4l2-core: fix v4l2_buffer handling for time64 ABI 



The v4l2_buffer structure contains a 'struct timeval' member that is
defined by the user space C library, creating an ABI incompatibility
when that gets updated to a 64-bit time_t.

As in v4l2_event, handle this with a special case in video_put_user()
and video_get_user() to replace the memcpy there.

Since the structure also contains a pointer, there are now two
native versions (on 32-bit systems) as well as two compat versions
(on 64-bit systems), which unfortunately complicates the compat
handler quite a bit.

Duplicating the existing handlers for the new types is a safe
conversion for now, but unfortunately this may turn into a
maintenance burden later. A larger-scale rework of the
compat code might be a better alternative, but is out of scope
of the y2038 work.

Sparc64 needs a special case because of their special suseconds_t
definition.

Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent 1a6c0b36

drivers/media/v4l2-core/v4l2-ioctl.c

+70 −4
Original line number Diff line number Diff line
@@ -474,10 +474,10 @@ static void v4l_print_buffer(const void *arg, bool write_only) 
	const struct v4l2_plane *plane;

	int i;



	pr_cont("%02ld:%02d:%02d.%08ld index=%d, type=%s, request_fd=%d, flags=0x%08x, field=%s, sequence=%d, memory=%s",

			p->timestamp.tv_sec / 3600,

			(int)(p->timestamp.tv_sec / 60) % 60,

			(int)(p->timestamp.tv_sec % 60),

	pr_cont("%02d:%02d:%02d.%09ld index=%d, type=%s, request_fd=%d, flags=0x%08x, field=%s, sequence=%d, memory=%s",

			(int)p->timestamp.tv_sec / 3600,

			((int)p->timestamp.tv_sec / 60) % 60,

			((int)p->timestamp.tv_sec % 60),

			(long)p->timestamp.tv_usec,

			p->index,

			prt_names(p->type, v4l2_type_names), p->request_fd,
@@ -3029,6 +3029,14 @@ static unsigned int video_translate_cmd(unsigned int cmd) 
#ifdef CONFIG_COMPAT_32BIT_TIME

	case VIDIOC_DQEVENT_TIME32:

		return VIDIOC_DQEVENT;

	case VIDIOC_QUERYBUF_TIME32:

		return VIDIOC_QUERYBUF;

	case VIDIOC_QBUF_TIME32:

		return VIDIOC_QBUF;

	case VIDIOC_DQBUF_TIME32:

		return VIDIOC_DQBUF;

	case VIDIOC_PREPARE_BUF_TIME32:

		return VIDIOC_PREPARE_BUF;

#endif

	}
@@ -3047,6 +3055,39 @@ static int video_get_user(void __user *arg, void *parg, unsigned int cmd, 
	}



	switch (cmd) {

#ifdef CONFIG_COMPAT_32BIT_TIME

	case VIDIOC_QUERYBUF_TIME32:

	case VIDIOC_QBUF_TIME32:

	case VIDIOC_DQBUF_TIME32:

	case VIDIOC_PREPARE_BUF_TIME32: {

		struct v4l2_buffer_time32 vb32;

		struct v4l2_buffer *vb = parg;



		if (copy_from_user(&vb32, arg, sizeof(vb32)))

			return -EFAULT;



		*vb = (struct v4l2_buffer) {

			.index		= vb32.index,

			.type		= vb32.type,

			.bytesused	= vb32.bytesused,

			.flags		= vb32.flags,

			.field		= vb32.field,

			.timestamp.tv_sec	= vb32.timestamp.tv_sec,

			.timestamp.tv_usec	= vb32.timestamp.tv_usec,

			.timecode	= vb32.timecode,

			.sequence	= vb32.sequence,

			.memory		= vb32.memory,

			.m.userptr	= vb32.m.userptr,

			.length		= vb32.length,

			.request_fd	= vb32.request_fd,

		};



		if (cmd == VIDIOC_QUERYBUF_TIME32)

			vb->request_fd = 0;



		break;

	}

#endif

	default:

		/*

		 * In some cases, only a few fields are used as input,
@@ -3100,6 +3141,31 @@ static int video_put_user(void __user *arg, void *parg, unsigned int cmd) 
			return -EFAULT;

		break;

	}

	case VIDIOC_QUERYBUF_TIME32:

	case VIDIOC_QBUF_TIME32:

	case VIDIOC_DQBUF_TIME32:

	case VIDIOC_PREPARE_BUF_TIME32: {

		struct v4l2_buffer *vb = parg;

		struct v4l2_buffer_time32 vb32 = {

			.index		= vb->index,

			.type		= vb->type,

			.bytesused	= vb->bytesused,

			.flags		= vb->flags,

			.field		= vb->field,

			.timestamp.tv_sec	= vb->timestamp.tv_sec,

			.timestamp.tv_usec	= vb->timestamp.tv_usec,

			.timecode	= vb->timecode,

			.sequence	= vb->sequence,

			.memory		= vb->memory,

			.m.userptr	= vb->m.userptr,

			.length		= vb->length,

			.request_fd	= vb->request_fd,

		};



		if (copy_to_user(arg, &vb32, sizeof(vb32)))

			return -EFAULT;

		break;

	}

#endif

	default:

		/*  Copy results into user buffer  */

include/media/v4l2-ioctl.h

+30 −0
Original line number Diff line number Diff line
@@ -749,4 +749,34 @@ struct v4l2_event_time32 { 


#define	VIDIOC_DQEVENT_TIME32	 _IOR('V', 89, struct v4l2_event_time32)



struct v4l2_buffer_time32 {

	__u32			index;

	__u32			type;

	__u32			bytesused;

	__u32			flags;

	__u32			field;

	struct old_timeval32	timestamp;

	struct v4l2_timecode	timecode;

	__u32			sequence;



	/* memory location */

	__u32			memory;

	union {

		__u32           offset;

		unsigned long   userptr;

		struct v4l2_plane *planes;

		__s32		fd;

	} m;

	__u32			length;

	__u32			reserved2;

	union {

		__s32		request_fd;

		__u32		reserved;

	};

};

#define VIDIOC_QUERYBUF_TIME32	_IOWR('V',  9, struct v4l2_buffer_time32)

#define VIDIOC_QBUF_TIME32	_IOWR('V', 15, struct v4l2_buffer_time32)

#define VIDIOC_DQBUF_TIME32	_IOWR('V', 17, struct v4l2_buffer_time32)

#define VIDIOC_PREPARE_BUF_TIME32 _IOWR('V', 93, struct v4l2_buffer_time32)



#endif /* _V4L2_IOCTL_H */

include/uapi/linux/videodev2.h

+23 −0
Original line number Diff line number Diff line
@@ -912,6 +912,25 @@ struct v4l2_jpegcompression { 
/*

 *	M E M O R Y - M A P P I N G   B U F F E R S

 */



#ifdef __KERNEL__

/*

 * This corresponds to the user space version of timeval

 * for 64-bit time_t. sparc64 is different from everyone

 * else, using the microseconds in the wrong half of the

 * second 64-bit word.

 */

struct __kernel_v4l2_timeval {

	long long	tv_sec;

#if defined(__sparc__) && defined(__arch64__)

	int		tv_usec;

	int		__pad;

#else

	long long	tv_usec;

#endif

};

#endif



struct v4l2_requestbuffers {

	__u32			count;

	__u32			type;		/* enum v4l2_buf_type */
@@ -997,7 +1016,11 @@ struct v4l2_buffer { 
	__u32			bytesused;

	__u32			flags;

	__u32			field;

#ifdef __KERNEL__

	struct __kernel_v4l2_timeval timestamp;

#else

	struct timeval		timestamp;

#endif

	struct v4l2_timecode	timecode;

	__u32			sequence;