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* [PATCH v5 0/8] y2038 safety in v4l2
@ 2019-11-26 16:18 Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 1/8] media: documentation: fix video_event description Arnd Bergmann
                   ` (8 more replies)
  0 siblings, 9 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 16:18 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann

I'm in the process of finishing up the last bits on y2038-unsafe
code in the kernel, this series is for v4l2, which has no problem
with overflow, but has multiple ioctls that break with user space
built against a new 32-bit libc.

I posted similar patches as part of a series back in 2015, the
new version was rewritten from scratch and I double-checked with
the old version to make sure I did not miss anything I had already
taken care of before.

Hans Verkuil worked on a different patch set in 2017, but this
also did not get to the point of being merged.

My new version contains compat-ioctl support, which the old one
did not and should be complete, but given its size likely contains
bugs. I did randconfig build tests, but no runtime test, so
careful review as well as testing would be much appreciated.

With this version, the newly added code takes care of the existing
ABI, while the existing code got moved to the 64-bit time_t
interface and is used internally. This means that testing with
existing binaries should exercise most of the modifications
and if that works and doesn't get shot down in review, we can
probably live without testing the new ABI explicitly.

I'm not entirely happy with the compat-ioctl implementation that
adds quite a bit of code duplication, but I hope this is
acceptable anyway, as a better implementation would likely
require a larger refactoring of the compat-ioctl file, while
my approach simply adds support for the additional data structure
variants.

I uploaded git branch on top of the v4l2/dvb branch to [2].

      Arnd

Changes since v4:

- Move non-public contents out of uapi header
- split out __kernel_v4l2_timeval into separate struct
- use compound initializers for v4l2_event_time32 and
  v4l2_buffer_time32 conversion
- add comment for v4l2_buffer_get_timestamp()

Changes since v3:

- This is a minor update compared to version 3 of this series,
  with bugfixes for small mistakes that I found or that were
  reported by automated build bots.


[1] https://lwn.net/Articles/657754/
[2] https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/log/?h=y2038-v4l2-v5

Arnd Bergmann (8):
  media: documentation: fix video_event description
  media: v4l2: abstract timeval handling in v4l2_buffer
  media: v4l2-core: compat: ignore native command codes
  media: v4l2-core: split out data copy from video_usercopy
  media: v4l2-core: fix VIDIOC_DQEVENT for time64 ABI
  media: v4l2-core: fix v4l2_buffer handling for time64 ABI
  media: v4l2-core: fix compat VIDIOC_DQEVENT for time64 ABI
  media: v4l2-core: fix compat v4l2_buffer handling for time64 ABI

 .../media/uapi/dvb/video-get-event.rst        |   2 +-
 Documentation/media/uapi/dvb/video_types.rst  |   2 +-
 .../media/common/videobuf2/videobuf2-v4l2.c   |   4 +-
 drivers/media/pci/meye/meye.c                 |   4 +-
 drivers/media/usb/cpia2/cpia2_v4l.c           |   4 +-
 drivers/media/usb/stkwebcam/stk-webcam.c      |   2 +-
 drivers/media/usb/usbvision/usbvision-video.c |   4 +-
 drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 470 +++++++++++++++---
 drivers/media/v4l2-core/v4l2-event.c          |   5 +-
 drivers/media/v4l2-core/v4l2-ioctl.c          | 209 ++++++--
 drivers/media/v4l2-core/v4l2-subdev.c         |  26 +-
 drivers/media/v4l2-core/videobuf-core.c       |   5 +-
 include/media/v4l2-common.h                   |  21 +
 include/media/v4l2-ioctl.h                    |  55 ++
 include/trace/events/v4l2.h                   |   2 +-
 include/uapi/linux/videodev2.h                |  29 ++
 16 files changed, 709 insertions(+), 135 deletions(-)

-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5 1/8] media: documentation: fix video_event description
  2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
@ 2019-11-26 16:18 ` Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 2/8] media: v4l2: abstract timeval handling in v4l2_buffer Arnd Bergmann
                   ` (7 subsequent siblings)
  8 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 16:18 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann

The type for the timestamp in video_event was changed to
'long' a long time ago, change the documentation to match.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 Documentation/media/uapi/dvb/video-get-event.rst | 2 +-
 Documentation/media/uapi/dvb/video_types.rst     | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/media/uapi/dvb/video-get-event.rst b/Documentation/media/uapi/dvb/video-get-event.rst
index def6c40db601..7f03fbe3d3b0 100644
--- a/Documentation/media/uapi/dvb/video-get-event.rst
+++ b/Documentation/media/uapi/dvb/video-get-event.rst
@@ -81,7 +81,7 @@ for this ioctl call.
 	#define VIDEO_EVENT_FRAME_RATE_CHANGED	2
 	#define VIDEO_EVENT_DECODER_STOPPED 	3
 	#define VIDEO_EVENT_VSYNC 		4
-		__kernel_time_t timestamp;
+		long timestamp;
 		union {
 			video_size_t size;
 			unsigned int frame_rate;	/* in frames per 1000sec */
diff --git a/Documentation/media/uapi/dvb/video_types.rst b/Documentation/media/uapi/dvb/video_types.rst
index 479942ce6fb8..2697400ccf62 100644
--- a/Documentation/media/uapi/dvb/video_types.rst
+++ b/Documentation/media/uapi/dvb/video_types.rst
@@ -170,7 +170,7 @@ VIDEO_GET_EVENT call.
     #define VIDEO_EVENT_FRAME_RATE_CHANGED  2
     #define VIDEO_EVENT_DECODER_STOPPED     3
     #define VIDEO_EVENT_VSYNC       4
-	__kernel_time_t timestamp;
+	long timestamp;
 	union {
 	    video_size_t size;
 	    unsigned int frame_rate;    /* in frames per 1000sec */
-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5 2/8] media: v4l2: abstract timeval handling in v4l2_buffer
  2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 1/8] media: documentation: fix video_event description Arnd Bergmann
@ 2019-11-26 16:18 ` Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 3/8] media: v4l2-core: compat: ignore native command codes Arnd Bergmann
                   ` (6 subsequent siblings)
  8 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 16:18 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann

As a preparation for adding 64-bit time_t support in the uapi,
change the drivers to no longer care about the format of the
timestamp field in struct v4l2_buffer.

The v4l2_timeval_to_ns() function is no longer needed in the
kernel after this, but there is userspace code relying on
it to be part of the uapi header.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 .../media/common/videobuf2/videobuf2-v4l2.c   |  4 ++--
 drivers/media/pci/meye/meye.c                 |  4 ++--
 drivers/media/usb/cpia2/cpia2_v4l.c           |  4 ++--
 drivers/media/usb/stkwebcam/stk-webcam.c      |  2 +-
 drivers/media/usb/usbvision/usbvision-video.c |  4 ++--
 drivers/media/v4l2-core/videobuf-core.c       |  5 +++--
 include/media/v4l2-common.h                   | 21 +++++++++++++++++++
 include/trace/events/v4l2.h                   |  2 +-
 include/uapi/linux/videodev2.h                |  2 ++
 9 files changed, 36 insertions(+), 12 deletions(-)

diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index e652f4318284..eb5d5db96552 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -146,7 +146,7 @@ static void __copy_timestamp(struct vb2_buffer *vb, const void *pb)
 		 * and the timecode field and flag if needed.
 		 */
 		if (q->copy_timestamp)
-			vb->timestamp = v4l2_timeval_to_ns(&b->timestamp);
+			vb->timestamp = v4l2_buffer_get_timestamp(b);
 		vbuf->flags |= b->flags & V4L2_BUF_FLAG_TIMECODE;
 		if (b->flags & V4L2_BUF_FLAG_TIMECODE)
 			vbuf->timecode = b->timecode;
@@ -482,7 +482,7 @@ static void __fill_v4l2_buffer(struct vb2_buffer *vb, void *pb)
 
 	b->flags = vbuf->flags;
 	b->field = vbuf->field;
-	b->timestamp = ns_to_timeval(vb->timestamp);
+	v4l2_buffer_set_timestamp(b, vb->timestamp);
 	b->timecode = vbuf->timecode;
 	b->sequence = vbuf->sequence;
 	b->reserved2 = 0;
diff --git a/drivers/media/pci/meye/meye.c b/drivers/media/pci/meye/meye.c
index 0e61c81356ef..3a4c29bc0ba5 100644
--- a/drivers/media/pci/meye/meye.c
+++ b/drivers/media/pci/meye/meye.c
@@ -1266,7 +1266,7 @@ static int vidioc_querybuf(struct file *file, void *fh, struct v4l2_buffer *buf)
 		buf->flags |= V4L2_BUF_FLAG_DONE;
 
 	buf->field = V4L2_FIELD_NONE;
-	buf->timestamp = ns_to_timeval(meye.grab_buffer[index].ts);
+	v4l2_buffer_set_timestamp(buf, meye.grab_buffer[index].ts);
 	buf->sequence = meye.grab_buffer[index].sequence;
 	buf->memory = V4L2_MEMORY_MMAP;
 	buf->m.offset = index * gbufsize;
@@ -1332,7 +1332,7 @@ static int vidioc_dqbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
 	buf->bytesused = meye.grab_buffer[reqnr].size;
 	buf->flags = V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
 	buf->field = V4L2_FIELD_NONE;
-	buf->timestamp = ns_to_timeval(meye.grab_buffer[reqnr].ts);
+	v4l2_buffer_set_timestamp(buf, meye.grab_buffer[reqnr].ts);
 	buf->sequence = meye.grab_buffer[reqnr].sequence;
 	buf->memory = V4L2_MEMORY_MMAP;
 	buf->m.offset = reqnr * gbufsize;
diff --git a/drivers/media/usb/cpia2/cpia2_v4l.c b/drivers/media/usb/cpia2/cpia2_v4l.c
index 626264a56517..9d3d05125d7b 100644
--- a/drivers/media/usb/cpia2/cpia2_v4l.c
+++ b/drivers/media/usb/cpia2/cpia2_v4l.c
@@ -800,7 +800,7 @@ static int cpia2_querybuf(struct file *file, void *fh, struct v4l2_buffer *buf)
 		break;
 	case FRAME_READY:
 		buf->bytesused = cam->buffers[buf->index].length;
-		buf->timestamp = ns_to_timeval(cam->buffers[buf->index].ts);
+		v4l2_buffer_set_timestamp(buf, cam->buffers[buf->index].ts);
 		buf->sequence = cam->buffers[buf->index].seq;
 		buf->flags = V4L2_BUF_FLAG_DONE;
 		break;
@@ -907,7 +907,7 @@ static int cpia2_dqbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
 	buf->flags = V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_DONE
 		| V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
 	buf->field = V4L2_FIELD_NONE;
-	buf->timestamp = ns_to_timeval(cam->buffers[buf->index].ts);
+	v4l2_buffer_set_timestamp(buf, cam->buffers[buf->index].ts);
 	buf->sequence = cam->buffers[buf->index].seq;
 	buf->m.offset = cam->buffers[buf->index].data - cam->frame_buffer;
 	buf->length = cam->frame_size;
diff --git a/drivers/media/usb/stkwebcam/stk-webcam.c b/drivers/media/usb/stkwebcam/stk-webcam.c
index cfca3c70599b..1b730ac31499 100644
--- a/drivers/media/usb/stkwebcam/stk-webcam.c
+++ b/drivers/media/usb/stkwebcam/stk-webcam.c
@@ -1126,7 +1126,7 @@ static int stk_vidioc_dqbuf(struct file *filp,
 	sbuf->v4lbuf.flags &= ~V4L2_BUF_FLAG_QUEUED;
 	sbuf->v4lbuf.flags |= V4L2_BUF_FLAG_DONE;
 	sbuf->v4lbuf.sequence = ++dev->sequence;
-	sbuf->v4lbuf.timestamp = ns_to_timeval(ktime_get_ns());
+	v4l2_buffer_set_timestamp(&sbuf->v4lbuf, ktime_get_ns());
 
 	*buf = sbuf->v4lbuf;
 	return 0;
diff --git a/drivers/media/usb/usbvision/usbvision-video.c b/drivers/media/usb/usbvision/usbvision-video.c
index 93d36aab824f..5ca2c2f35fe2 100644
--- a/drivers/media/usb/usbvision/usbvision-video.c
+++ b/drivers/media/usb/usbvision/usbvision-video.c
@@ -696,7 +696,7 @@ static int vidioc_querybuf(struct file *file,
 	vb->length = usbvision->curwidth *
 		usbvision->curheight *
 		usbvision->palette.bytes_per_pixel;
-	vb->timestamp = ns_to_timeval(usbvision->frame[vb->index].ts);
+	v4l2_buffer_set_timestamp(vb, usbvision->frame[vb->index].ts);
 	vb->sequence = usbvision->frame[vb->index].sequence;
 	return 0;
 }
@@ -765,7 +765,7 @@ static int vidioc_dqbuf(struct file *file, void *priv, struct v4l2_buffer *vb)
 		V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
 	vb->index = f->index;
 	vb->sequence = f->sequence;
-	vb->timestamp = ns_to_timeval(f->ts);
+	v4l2_buffer_set_timestamp(vb, f->ts);
 	vb->field = V4L2_FIELD_NONE;
 	vb->bytesused = f->scanlength;
 
diff --git a/drivers/media/v4l2-core/videobuf-core.c b/drivers/media/v4l2-core/videobuf-core.c
index 939fc11cf080..2686f03b322e 100644
--- a/drivers/media/v4l2-core/videobuf-core.c
+++ b/drivers/media/v4l2-core/videobuf-core.c
@@ -19,6 +19,7 @@
 #include <linux/interrupt.h>
 
 #include <media/videobuf-core.h>
+#include <media/v4l2-common.h>
 
 #define MAGIC_BUFFER 0x20070728
 #define MAGIC_CHECK(is, should)						\
@@ -364,7 +365,7 @@ static void videobuf_status(struct videobuf_queue *q, struct v4l2_buffer *b,
 	}
 
 	b->field     = vb->field;
-	b->timestamp = ns_to_timeval(vb->ts);
+	v4l2_buffer_set_timestamp(b, vb->ts);
 	b->bytesused = vb->size;
 	b->sequence  = vb->field_count >> 1;
 }
@@ -578,7 +579,7 @@ int videobuf_qbuf(struct videobuf_queue *q, struct v4l2_buffer *b)
 		    || q->type == V4L2_BUF_TYPE_SDR_OUTPUT) {
 			buf->size = b->bytesused;
 			buf->field = b->field;
-			buf->ts = v4l2_timeval_to_ns(&b->timestamp);
+			buf->ts = v4l2_buffer_get_timestamp(b);
 		}
 		break;
 	case V4L2_MEMORY_USERPTR:
diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
index d8c29e089000..8d0ac0311c84 100644
--- a/include/media/v4l2-common.h
+++ b/include/media/v4l2-common.h
@@ -14,6 +14,7 @@
 #ifndef V4L2_COMMON_H_
 #define V4L2_COMMON_H_
 
+#include <linux/time.h>
 #include <media/v4l2-dev.h>
 
 /* Common printk constructs for v4l-i2c drivers. These macros create a unique
@@ -518,4 +519,24 @@ int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat,
 int v4l2_fill_pixfmt_mp(struct v4l2_pix_format_mplane *pixfmt, u32 pixelformat,
 			u32 width, u32 height);
 
+static inline u64 v4l2_buffer_get_timestamp(const struct v4l2_buffer *buf)
+{
+	/*
+	 * When the timestamp comes from 32-bit user space, there may be
+	 * uninitialized data in tv_usec, so cast it to u32.
+	 * Otherwise allow invalid input for backwards compatibility.
+	 */
+	return buf->timestamp.tv_sec * NSEC_PER_SEC +
+		(u32)buf->timestamp.tv_usec * NSEC_PER_USEC;
+}
+
+static inline void v4l2_buffer_set_timestamp(struct v4l2_buffer *buf,
+                                            u64 timestamp)
+{
+	struct timespec64 ts = ns_to_timespec64(timestamp);
+
+	buf->timestamp.tv_sec  = ts.tv_sec;
+	buf->timestamp.tv_usec = ts.tv_nsec / NSEC_PER_USEC;
+}
+
 #endif /* V4L2_COMMON_H_ */
diff --git a/include/trace/events/v4l2.h b/include/trace/events/v4l2.h
index 83860de120e3..248bc09bfc99 100644
--- a/include/trace/events/v4l2.h
+++ b/include/trace/events/v4l2.h
@@ -130,7 +130,7 @@ DECLARE_EVENT_CLASS(v4l2_event_class,
 		__entry->bytesused = buf->bytesused;
 		__entry->flags = buf->flags;
 		__entry->field = buf->field;
-		__entry->timestamp = timeval_to_ns(&buf->timestamp);
+		__entry->timestamp = v4l2_buffer_get_timestamp(buf);
 		__entry->timecode_type = buf->timecode.type;
 		__entry->timecode_flags = buf->timecode.flags;
 		__entry->timecode_frames = buf->timecode.frames;
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 04481c717fee..6ef4a5b787a4 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -1017,6 +1017,7 @@ struct v4l2_buffer {
 	};
 };
 
+#ifndef __KERNEL__
 /**
  * v4l2_timeval_to_ns - Convert timeval to nanoseconds
  * @ts:		pointer to the timeval variable to be converted
@@ -1028,6 +1029,7 @@ static inline __u64 v4l2_timeval_to_ns(const struct timeval *tv)
 {
 	return (__u64)tv->tv_sec * 1000000000ULL + tv->tv_usec * 1000;
 }
+#endif
 
 /*  Flags for 'flags' field */
 /* Buffer is mapped (flag) */
-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5 3/8] media: v4l2-core: compat: ignore native command codes
  2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 1/8] media: documentation: fix video_event description Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 2/8] media: v4l2: abstract timeval handling in v4l2_buffer Arnd Bergmann
@ 2019-11-26 16:18 ` Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 4/8] media: v4l2-core: split out data copy from video_usercopy Arnd Bergmann
                   ` (5 subsequent siblings)
  8 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 16:18 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann, stable

The do_video_ioctl() compat handler converts the compat command
codes into the native ones before processing further, but this
causes problems for 32-bit user applications that pass a command
code that matches a 64-bit native number, which will then be
handled the same way.

Specifically, this breaks VIDIOC_DQEVENT_TIME from user space
applications with 64-bit time_t, as the structure layout is
the same as the native 64-bit layout on many architectures
(x86 being the notable exception).

Change the handler to use the converted command code only for
passing into the native ioctl handler, not for deciding on the
conversion, in order to make the compat behavior match the
native behavior.

Actual support for the 64-bit time_t version of VIDIOC_DQEVENT_TIME
and other commands still needs to be added in a separate patch.

Cc: stable@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 148 +++++++++---------
 1 file changed, 75 insertions(+), 73 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
index e1eaf1135c7f..7ad6db8dd9f6 100644
--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -1183,36 +1183,38 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 	u32 aux_space;
 	int compatible_arg = 1;
 	long err = 0;
+	unsigned int ncmd;
 
 	/*
 	 * 1. When struct size is different, converts the command.
 	 */
 	switch (cmd) {
-	case VIDIOC_G_FMT32: cmd = VIDIOC_G_FMT; break;
-	case VIDIOC_S_FMT32: cmd = VIDIOC_S_FMT; break;
-	case VIDIOC_QUERYBUF32: cmd = VIDIOC_QUERYBUF; break;
-	case VIDIOC_G_FBUF32: cmd = VIDIOC_G_FBUF; break;
-	case VIDIOC_S_FBUF32: cmd = VIDIOC_S_FBUF; break;
-	case VIDIOC_QBUF32: cmd = VIDIOC_QBUF; break;
-	case VIDIOC_DQBUF32: cmd = VIDIOC_DQBUF; break;
-	case VIDIOC_ENUMSTD32: cmd = VIDIOC_ENUMSTD; break;
-	case VIDIOC_ENUMINPUT32: cmd = VIDIOC_ENUMINPUT; break;
-	case VIDIOC_TRY_FMT32: cmd = VIDIOC_TRY_FMT; break;
-	case VIDIOC_G_EXT_CTRLS32: cmd = VIDIOC_G_EXT_CTRLS; break;
-	case VIDIOC_S_EXT_CTRLS32: cmd = VIDIOC_S_EXT_CTRLS; break;
-	case VIDIOC_TRY_EXT_CTRLS32: cmd = VIDIOC_TRY_EXT_CTRLS; break;
-	case VIDIOC_DQEVENT32: cmd = VIDIOC_DQEVENT; break;
-	case VIDIOC_OVERLAY32: cmd = VIDIOC_OVERLAY; break;
-	case VIDIOC_STREAMON32: cmd = VIDIOC_STREAMON; break;
-	case VIDIOC_STREAMOFF32: cmd = VIDIOC_STREAMOFF; break;
-	case VIDIOC_G_INPUT32: cmd = VIDIOC_G_INPUT; break;
-	case VIDIOC_S_INPUT32: cmd = VIDIOC_S_INPUT; break;
-	case VIDIOC_G_OUTPUT32: cmd = VIDIOC_G_OUTPUT; break;
-	case VIDIOC_S_OUTPUT32: cmd = VIDIOC_S_OUTPUT; break;
-	case VIDIOC_CREATE_BUFS32: cmd = VIDIOC_CREATE_BUFS; break;
-	case VIDIOC_PREPARE_BUF32: cmd = VIDIOC_PREPARE_BUF; break;
-	case VIDIOC_G_EDID32: cmd = VIDIOC_G_EDID; break;
-	case VIDIOC_S_EDID32: cmd = VIDIOC_S_EDID; break;
+	case VIDIOC_G_FMT32: ncmd = VIDIOC_G_FMT; break;
+	case VIDIOC_S_FMT32: ncmd = VIDIOC_S_FMT; break;
+	case VIDIOC_QUERYBUF32: ncmd = VIDIOC_QUERYBUF; break;
+	case VIDIOC_G_FBUF32: ncmd = VIDIOC_G_FBUF; break;
+	case VIDIOC_S_FBUF32: ncmd = VIDIOC_S_FBUF; break;
+	case VIDIOC_QBUF32: ncmd = VIDIOC_QBUF; break;
+	case VIDIOC_DQBUF32: ncmd = VIDIOC_DQBUF; break;
+	case VIDIOC_ENUMSTD32: ncmd = VIDIOC_ENUMSTD; break;
+	case VIDIOC_ENUMINPUT32: ncmd = VIDIOC_ENUMINPUT; break;
+	case VIDIOC_TRY_FMT32: ncmd = VIDIOC_TRY_FMT; break;
+	case VIDIOC_G_EXT_CTRLS32: ncmd = VIDIOC_G_EXT_CTRLS; break;
+	case VIDIOC_S_EXT_CTRLS32: ncmd = VIDIOC_S_EXT_CTRLS; break;
+	case VIDIOC_TRY_EXT_CTRLS32: ncmd = VIDIOC_TRY_EXT_CTRLS; break;
+	case VIDIOC_DQEVENT32: ncmd = VIDIOC_DQEVENT; break;
+	case VIDIOC_OVERLAY32: ncmd = VIDIOC_OVERLAY; break;
+	case VIDIOC_STREAMON32: ncmd = VIDIOC_STREAMON; break;
+	case VIDIOC_STREAMOFF32: ncmd = VIDIOC_STREAMOFF; break;
+	case VIDIOC_G_INPUT32: ncmd = VIDIOC_G_INPUT; break;
+	case VIDIOC_S_INPUT32: ncmd = VIDIOC_S_INPUT; break;
+	case VIDIOC_G_OUTPUT32: ncmd = VIDIOC_G_OUTPUT; break;
+	case VIDIOC_S_OUTPUT32: ncmd = VIDIOC_S_OUTPUT; break;
+	case VIDIOC_CREATE_BUFS32: ncmd = VIDIOC_CREATE_BUFS; break;
+	case VIDIOC_PREPARE_BUF32: ncmd = VIDIOC_PREPARE_BUF; break;
+	case VIDIOC_G_EDID32: ncmd = VIDIOC_G_EDID; break;
+	case VIDIOC_S_EDID32: ncmd = VIDIOC_S_EDID; break;
+	default: ncmd = cmd; break;
 	}
 
 	/*
@@ -1221,11 +1223,11 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 	 * argument into it.
 	 */
 	switch (cmd) {
-	case VIDIOC_OVERLAY:
-	case VIDIOC_STREAMON:
-	case VIDIOC_STREAMOFF:
-	case VIDIOC_S_INPUT:
-	case VIDIOC_S_OUTPUT:
+	case VIDIOC_OVERLAY32:
+	case VIDIOC_STREAMON32:
+	case VIDIOC_STREAMOFF32:
+	case VIDIOC_S_INPUT32:
+	case VIDIOC_S_OUTPUT32:
 		err = alloc_userspace(sizeof(unsigned int), 0, &new_p64);
 		if (!err && assign_in_user((unsigned int __user *)new_p64,
 					   (compat_uint_t __user *)p32))
@@ -1233,23 +1235,23 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_G_INPUT:
-	case VIDIOC_G_OUTPUT:
+	case VIDIOC_G_INPUT32:
+	case VIDIOC_G_OUTPUT32:
 		err = alloc_userspace(sizeof(unsigned int), 0, &new_p64);
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_G_EDID:
-	case VIDIOC_S_EDID:
+	case VIDIOC_G_EDID32:
+	case VIDIOC_S_EDID32:
 		err = alloc_userspace(sizeof(struct v4l2_edid), 0, &new_p64);
 		if (!err)
 			err = get_v4l2_edid32(new_p64, p32);
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_G_FMT:
-	case VIDIOC_S_FMT:
-	case VIDIOC_TRY_FMT:
+	case VIDIOC_G_FMT32:
+	case VIDIOC_S_FMT32:
+	case VIDIOC_TRY_FMT32:
 		err = bufsize_v4l2_format(p32, &aux_space);
 		if (!err)
 			err = alloc_userspace(sizeof(struct v4l2_format),
@@ -1262,7 +1264,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_CREATE_BUFS:
+	case VIDIOC_CREATE_BUFS32:
 		err = bufsize_v4l2_create(p32, &aux_space);
 		if (!err)
 			err = alloc_userspace(sizeof(struct v4l2_create_buffers),
@@ -1275,10 +1277,10 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_PREPARE_BUF:
-	case VIDIOC_QUERYBUF:
-	case VIDIOC_QBUF:
-	case VIDIOC_DQBUF:
+	case VIDIOC_PREPARE_BUF32:
+	case VIDIOC_QUERYBUF32:
+	case VIDIOC_QBUF32:
+	case VIDIOC_DQBUF32:
 		err = bufsize_v4l2_buffer(p32, &aux_space);
 		if (!err)
 			err = alloc_userspace(sizeof(struct v4l2_buffer),
@@ -1291,7 +1293,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_S_FBUF:
+	case VIDIOC_S_FBUF32:
 		err = alloc_userspace(sizeof(struct v4l2_framebuffer), 0,
 				      &new_p64);
 		if (!err)
@@ -1299,13 +1301,13 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_G_FBUF:
+	case VIDIOC_G_FBUF32:
 		err = alloc_userspace(sizeof(struct v4l2_framebuffer), 0,
 				      &new_p64);
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_ENUMSTD:
+	case VIDIOC_ENUMSTD32:
 		err = alloc_userspace(sizeof(struct v4l2_standard), 0,
 				      &new_p64);
 		if (!err)
@@ -1313,16 +1315,16 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_ENUMINPUT:
+	case VIDIOC_ENUMINPUT32:
 		err = alloc_userspace(sizeof(struct v4l2_input), 0, &new_p64);
 		if (!err)
 			err = get_v4l2_input32(new_p64, p32);
 		compatible_arg = 0;
 		break;
 
-	case VIDIOC_G_EXT_CTRLS:
-	case VIDIOC_S_EXT_CTRLS:
-	case VIDIOC_TRY_EXT_CTRLS:
+	case VIDIOC_G_EXT_CTRLS32:
+	case VIDIOC_S_EXT_CTRLS32:
+	case VIDIOC_TRY_EXT_CTRLS32:
 		err = bufsize_v4l2_ext_controls(p32, &aux_space);
 		if (!err)
 			err = alloc_userspace(sizeof(struct v4l2_ext_controls),
@@ -1334,7 +1336,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		}
 		compatible_arg = 0;
 		break;
-	case VIDIOC_DQEVENT:
+	case VIDIOC_DQEVENT32:
 		err = alloc_userspace(sizeof(struct v4l2_event), 0, &new_p64);
 		compatible_arg = 0;
 		break;
@@ -1352,9 +1354,9 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 	 * Otherwise, it will pass the newly allocated @new_p64 argument.
 	 */
 	if (compatible_arg)
-		err = native_ioctl(file, cmd, (unsigned long)p32);
+		err = native_ioctl(file, ncmd, (unsigned long)p32);
 	else
-		err = native_ioctl(file, cmd, (unsigned long)new_p64);
+		err = native_ioctl(file, ncmd, (unsigned long)new_p64);
 
 	if (err == -ENOTTY)
 		return err;
@@ -1370,13 +1372,13 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 	 * the blocks to maximum allowed value.
 	 */
 	switch (cmd) {
-	case VIDIOC_G_EXT_CTRLS:
-	case VIDIOC_S_EXT_CTRLS:
-	case VIDIOC_TRY_EXT_CTRLS:
+	case VIDIOC_G_EXT_CTRLS32:
+	case VIDIOC_S_EXT_CTRLS32:
+	case VIDIOC_TRY_EXT_CTRLS32:
 		if (put_v4l2_ext_controls32(file, new_p64, p32))
 			err = -EFAULT;
 		break;
-	case VIDIOC_S_EDID:
+	case VIDIOC_S_EDID32:
 		if (put_v4l2_edid32(new_p64, p32))
 			err = -EFAULT;
 		break;
@@ -1389,49 +1391,49 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 	 * the original 32 bits structure.
 	 */
 	switch (cmd) {
-	case VIDIOC_S_INPUT:
-	case VIDIOC_S_OUTPUT:
-	case VIDIOC_G_INPUT:
-	case VIDIOC_G_OUTPUT:
+	case VIDIOC_S_INPUT32:
+	case VIDIOC_S_OUTPUT32:
+	case VIDIOC_G_INPUT32:
+	case VIDIOC_G_OUTPUT32:
 		if (assign_in_user((compat_uint_t __user *)p32,
 				   ((unsigned int __user *)new_p64)))
 			err = -EFAULT;
 		break;
 
-	case VIDIOC_G_FBUF:
+	case VIDIOC_G_FBUF32:
 		err = put_v4l2_framebuffer32(new_p64, p32);
 		break;
 
-	case VIDIOC_DQEVENT:
+	case VIDIOC_DQEVENT32:
 		err = put_v4l2_event32(new_p64, p32);
 		break;
 
-	case VIDIOC_G_EDID:
+	case VIDIOC_G_EDID32:
 		err = put_v4l2_edid32(new_p64, p32);
 		break;
 
-	case VIDIOC_G_FMT:
-	case VIDIOC_S_FMT:
-	case VIDIOC_TRY_FMT:
+	case VIDIOC_G_FMT32:
+	case VIDIOC_S_FMT32:
+	case VIDIOC_TRY_FMT32:
 		err = put_v4l2_format32(new_p64, p32);
 		break;
 
-	case VIDIOC_CREATE_BUFS:
+	case VIDIOC_CREATE_BUFS32:
 		err = put_v4l2_create32(new_p64, p32);
 		break;
 
-	case VIDIOC_PREPARE_BUF:
-	case VIDIOC_QUERYBUF:
-	case VIDIOC_QBUF:
-	case VIDIOC_DQBUF:
+	case VIDIOC_PREPARE_BUF32:
+	case VIDIOC_QUERYBUF32:
+	case VIDIOC_QBUF32:
+	case VIDIOC_DQBUF32:
 		err = put_v4l2_buffer32(new_p64, p32);
 		break;
 
-	case VIDIOC_ENUMSTD:
+	case VIDIOC_ENUMSTD32:
 		err = put_v4l2_standard32(new_p64, p32);
 		break;
 
-	case VIDIOC_ENUMINPUT:
+	case VIDIOC_ENUMINPUT32:
 		err = put_v4l2_input32(new_p64, p32);
 		break;
 	}
-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5 4/8] media: v4l2-core: split out data copy from video_usercopy
  2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
                   ` (2 preceding siblings ...)
  2019-11-26 16:18 ` [PATCH v5 3/8] media: v4l2-core: compat: ignore native command codes Arnd Bergmann
@ 2019-11-26 16:18 ` Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 5/8] media: v4l2-core: fix VIDIOC_DQEVENT for time64 ABI Arnd Bergmann
                   ` (4 subsequent siblings)
  8 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 16:18 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann

The copy-in/out portions of video_usercopy() are about to
get more complex, so turn then into separate functions as
a cleanup first.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/media/v4l2-core/v4l2-ioctl.c | 107 +++++++++++++++++----------
 1 file changed, 68 insertions(+), 39 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 4e700583659b..2ce91f88369b 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -3023,8 +3023,69 @@ static int check_array_args(unsigned int cmd, void *parg, size_t *array_size,
 	return ret;
 }
 
+static unsigned int video_translate_cmd(unsigned int cmd)
+{
+	return cmd;
+}
+
+static int video_get_user(void __user *arg, void *parg, unsigned int cmd,
+			  bool *always_copy)
+{
+	unsigned int n = _IOC_SIZE(cmd);
+
+	if (!(_IOC_DIR(cmd) & _IOC_WRITE)) {
+		/* read-only ioctl */
+		memset(parg, 0, n);
+		return 0;
+	}
+
+	switch (cmd) {
+	default:
+		/*
+		 * In some cases, only a few fields are used as input,
+		 * i.e. when the app sets "index" and then the driver
+		 * fills in the rest of the structure for the thing
+		 * with that index.  We only need to copy up the first
+		 * non-input field.
+		 */
+		if (v4l2_is_known_ioctl(cmd)) {
+			u32 flags = v4l2_ioctls[_IOC_NR(cmd)].flags;
+
+			if (flags & INFO_FL_CLEAR_MASK)
+				n = (flags & INFO_FL_CLEAR_MASK) >> 16;
+			*always_copy = flags & INFO_FL_ALWAYS_COPY;
+		}
+
+		if (copy_from_user(parg, (void __user *)arg, n))
+			return -EFAULT;
+
+		/* zero out anything we don't copy from userspace */
+		if (n < _IOC_SIZE(cmd))
+			memset((u8 *)parg + n, 0, _IOC_SIZE(cmd) - n);
+		break;
+	}
+
+	return 0;
+}
+
+static int video_put_user(void __user *arg, void *parg, unsigned int cmd)
+{
+	if (!(_IOC_DIR(cmd) & _IOC_READ))
+		return 0;
+
+	switch (cmd) {
+	default:
+		/*  Copy results into user buffer  */
+		if (copy_to_user(arg, parg, _IOC_SIZE(cmd)))
+			return -EFAULT;
+		break;
+	}
+
+	return 0;
+}
+
 long
-video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
+video_usercopy(struct file *file, unsigned int orig_cmd, unsigned long arg,
 	       v4l2_kioctl func)
 {
 	char	sbuf[128];
@@ -3036,6 +3097,7 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
 	size_t  array_size = 0;
 	void __user *user_ptr = NULL;
 	void	**kernel_ptr = NULL;
+	unsigned int cmd = video_translate_cmd(orig_cmd);
 	const size_t ioc_size = _IOC_SIZE(cmd);
 
 	/*  Copy arguments into temp kernel buffer  */
@@ -3050,37 +3112,12 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
 			parg = mbuf;
 		}
 
-		err = -EFAULT;
-		if (_IOC_DIR(cmd) & _IOC_WRITE) {
-			unsigned int n = ioc_size;
-
-			/*
-			 * In some cases, only a few fields are used as input,
-			 * i.e. when the app sets "index" and then the driver
-			 * fills in the rest of the structure for the thing
-			 * with that index.  We only need to copy up the first
-			 * non-input field.
-			 */
-			if (v4l2_is_known_ioctl(cmd)) {
-				u32 flags = v4l2_ioctls[_IOC_NR(cmd)].flags;
-
-				if (flags & INFO_FL_CLEAR_MASK)
-					n = (flags & INFO_FL_CLEAR_MASK) >> 16;
-				always_copy = flags & INFO_FL_ALWAYS_COPY;
-			}
-
-			if (copy_from_user(parg, (void __user *)arg, n))
-				goto out;
-
-			/* zero out anything we don't copy from userspace */
-			if (n < ioc_size)
-				memset((u8 *)parg + n, 0, ioc_size - n);
-		} else {
-			/* read-only ioctl */
-			memset(parg, 0, ioc_size);
-		}
 	}
 
+	err = video_get_user((void __user *)arg, parg, orig_cmd, &always_copy);
+	if (err)
+		goto out;
+
 	err = check_array_args(cmd, parg, &array_size, &user_ptr, &kernel_ptr);
 	if (err < 0)
 		goto out;
@@ -3131,15 +3168,7 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
 		goto out;
 
 out_array_args:
-	/*  Copy results into user buffer  */
-	switch (_IOC_DIR(cmd)) {
-	case _IOC_READ:
-	case (_IOC_WRITE | _IOC_READ):
-		if (copy_to_user((void __user *)arg, parg, ioc_size))
-			err = -EFAULT;
-		break;
-	}
-
+	err = video_put_user((void __user *)arg, parg, orig_cmd);
 out:
 	kvfree(mbuf);
 	return err;
-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5 5/8] media: v4l2-core: fix VIDIOC_DQEVENT for time64 ABI
  2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
                   ` (3 preceding siblings ...)
  2019-11-26 16:18 ` [PATCH v5 4/8] media: v4l2-core: split out data copy from video_usercopy Arnd Bergmann
@ 2019-11-26 16:18 ` Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 6/8] media: v4l2-core: fix v4l2_buffer handling " Arnd Bergmann
                   ` (3 subsequent siblings)
  8 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 16:18 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann

The v4l2_event structure contains a 'struct timespec' member that is
defined by the user space C library, creating an ABI incompatibility
when that gets updated to a 64-bit time_t.

While passing a 32-bit time_t here would be sufficient for CLOCK_MONOTONIC
timestamps, simply redefining the structure to use the kernel's
__kernel_old_timespec would not work for any library that uses a copy
of the linux/videodev2.h header file rather than including the copy from
the latest kernel headers.

This means the kernel has to be changed to handle both versions of the
structure layout on a 32-bit architecture. The easiest way to do this
is during the copy from/to user space.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/media/v4l2-core/v4l2-event.c  |  5 ++++-
 drivers/media/v4l2-core/v4l2-ioctl.c  | 29 ++++++++++++++++++++++++++-
 drivers/media/v4l2-core/v4l2-subdev.c | 26 +++++++++++++++++++++++-
 include/media/v4l2-ioctl.h            | 25 +++++++++++++++++++++++
 include/uapi/linux/videodev2.h        |  4 ++++
 5 files changed, 86 insertions(+), 3 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-event.c b/drivers/media/v4l2-core/v4l2-event.c
index 9d673d113d7a..290c6b213179 100644
--- a/drivers/media/v4l2-core/v4l2-event.c
+++ b/drivers/media/v4l2-core/v4l2-event.c
@@ -27,6 +27,7 @@ static unsigned sev_pos(const struct v4l2_subscribed_event *sev, unsigned idx)
 static int __v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event)
 {
 	struct v4l2_kevent *kev;
+	struct timespec64 ts;
 	unsigned long flags;
 
 	spin_lock_irqsave(&fh->vdev->fh_lock, flags);
@@ -44,7 +45,9 @@ static int __v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event)
 
 	kev->event.pending = fh->navailable;
 	*event = kev->event;
-	event->timestamp = ns_to_timespec(kev->ts);
+	ts = ns_to_timespec64(kev->ts);
+	event->timestamp.tv_sec = ts.tv_sec;
+	event->timestamp.tv_nsec = ts.tv_nsec;
 	kev->sev->first = sev_pos(kev->sev, 1);
 	kev->sev->in_use--;
 
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 2ce91f88369b..96aafb659783 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -821,7 +821,7 @@ static void v4l_print_event(const void *arg, bool write_only)
 	const struct v4l2_event *p = arg;
 	const struct v4l2_event_ctrl *c;
 
-	pr_cont("type=0x%x, pending=%u, sequence=%u, id=%u, timestamp=%lu.%9.9lu\n",
+	pr_cont("type=0x%x, pending=%u, sequence=%u, id=%u, timestamp=%llu.%9.9llu\n",
 			p->type, p->pending, p->sequence, p->id,
 			p->timestamp.tv_sec, p->timestamp.tv_nsec);
 	switch (p->type) {
@@ -3025,6 +3025,13 @@ static int check_array_args(unsigned int cmd, void *parg, size_t *array_size,
 
 static unsigned int video_translate_cmd(unsigned int cmd)
 {
+	switch (cmd) {
+#ifdef CONFIG_COMPAT_32BIT_TIME
+	case VIDIOC_DQEVENT_TIME32:
+		return VIDIOC_DQEVENT;
+#endif
+	}
+
 	return cmd;
 }
 
@@ -3074,6 +3081,26 @@ static int video_put_user(void __user *arg, void *parg, unsigned int cmd)
 		return 0;
 
 	switch (cmd) {
+#ifdef CONFIG_COMPAT_32BIT_TIME
+	case VIDIOC_DQEVENT_TIME32: {
+		struct v4l2_event *ev = parg;
+		struct v4l2_event_time32 ev32 = {
+			.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));
+
+		if (copy_to_user(arg, &ev32, sizeof(ev32)))
+			return -EFAULT;
+		break;
+	}
+#endif
 	default:
 		/*  Copy results into user buffer  */
 		if (copy_to_user(arg, parg, _IOC_SIZE(cmd)))
diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 9e987c0f840e..de926e311348 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -331,8 +331,8 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 	struct v4l2_fh *vfh = file->private_data;
 #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
 	struct v4l2_subdev_fh *subdev_fh = to_v4l2_subdev_fh(vfh);
-	int rval;
 #endif
+	int rval;
 
 	switch (cmd) {
 	case VIDIOC_QUERYCTRL:
@@ -392,6 +392,30 @@ 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);
 
diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
index 4bba65a59d46..05c1ec93a911 100644
--- a/include/media/v4l2-ioctl.h
+++ b/include/media/v4l2-ioctl.h
@@ -724,4 +724,29 @@ long int video_usercopy(struct file *file, unsigned int cmd,
 long int video_ioctl2(struct file *file,
 		      unsigned int cmd, unsigned long int arg);
 
+/*
+ * The user space interpretation of the 'v4l2_event' differs
+ * based on the 'time_t' definition on 32-bit architectures, so
+ * the kernel has to handle both.
+ * This is the old version for 32-bit architectures.
+ */
+struct v4l2_event_time32 {
+	__u32				type;
+	union {
+		struct v4l2_event_vsync		vsync;
+		struct v4l2_event_ctrl		ctrl;
+		struct v4l2_event_frame_sync	frame_sync;
+		struct v4l2_event_src_change	src_change;
+		struct v4l2_event_motion_det	motion_det;
+		__u8				data[64];
+	} u;
+	__u32				pending;
+	__u32				sequence;
+	struct old_timespec32		timestamp;
+	__u32				id;
+	__u32				reserved[8];
+};
+
+#define	VIDIOC_DQEVENT_TIME32	 _IOR('V', 89, struct v4l2_event_time32)
+
 #endif /* _V4L2_IOCTL_H */
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 6ef4a5b787a4..caf156d45842 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -2341,7 +2341,11 @@ struct v4l2_event {
 	} u;
 	__u32				pending;
 	__u32				sequence;
+#ifdef __KERNEL__
+	struct __kernel_timespec	timestamp;
+#else
 	struct timespec			timestamp;
+#endif
 	__u32				id;
 	__u32				reserved[8];
 };
-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5 6/8] media: v4l2-core: fix v4l2_buffer handling for time64 ABI
  2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
                   ` (4 preceding siblings ...)
  2019-11-26 16:18 ` [PATCH v5 5/8] media: v4l2-core: fix VIDIOC_DQEVENT for time64 ABI Arnd Bergmann
@ 2019-11-26 16:18 ` " Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 7/8] media: v4l2-core: fix compat VIDIOC_DQEVENT " Arnd Bergmann
                   ` (2 subsequent siblings)
  8 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 16:18 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann

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: Arnd Bergmann <arnd@arndb.de>
---
 drivers/media/v4l2-core/v4l2-ioctl.c | 73 ++++++++++++++++++++++++++--
 include/media/v4l2-ioctl.h           | 30 ++++++++++++
 include/uapi/linux/videodev2.h       | 23 +++++++++
 3 files changed, 122 insertions(+), 4 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 96aafb659783..4d611a847462 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -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 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,
+			.memory		= vb32.memory,
+			.m.userptr	= vb32.m.usercopy,
+			.length		= vb32.length,
+			.request_fd	= vb32.request_fd,
+		};
+
+		if (cmd == VIDIOC_QUERYBUF_TIME32)
+			memset(&vb->length, 0, sizeof(*vb) -
+			       offsetof(struct v4l2_buffer, length));
+
+		break;
+	}
+#endif
 	default:
 		/*
 		 * In some cases, only a few fields are used as input,
@@ -3100,6 +3141,30 @@ 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,
+			.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  */
diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
index 05c1ec93a911..86878fba332b 100644
--- a/include/media/v4l2-ioctl.h
+++ b/include/media/v4l2-ioctl.h
@@ -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 */
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index caf156d45842..5f9357dcb060 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -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;
 
-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5 7/8] media: v4l2-core: fix compat VIDIOC_DQEVENT for time64 ABI
  2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
                   ` (5 preceding siblings ...)
  2019-11-26 16:18 ` [PATCH v5 6/8] media: v4l2-core: fix v4l2_buffer handling " Arnd Bergmann
@ 2019-11-26 16:18 ` " Arnd Bergmann
  2019-11-26 16:18 ` [PATCH v5 8/8] media: v4l2-core: fix compat v4l2_buffer handling " Arnd Bergmann
  2019-11-26 19:55 ` [PATCH v5.1 4/8] media: v4l2-core: split out data copy from video_usercopy Arnd Bergmann
  8 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 16:18 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann

The native code supports the variant of struct v4l2_event for 64-bit
time_t, so add the compat version as well.

Here, a new incompatibility arises: while almost all 32-bit architectures
now use the same layout as 64-bit architectures and the commands can
simply be passed through, on x86 the internal alignment of v4l2_event
is different because of the 64-bit member in v4l2_event_ctrl.

To handle all architectures, this now requires defining four different
versions of the structure to cover all possible combinations. The compat
handling for VIDIOC_DQEVENT32 and VIDIOC_DQEVENT32_TIME32 is now inside
of an #ifdef so it does not get used on architectures other than x86.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 57 ++++++++++++++++++-
 1 file changed, 56 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
index 7ad6db8dd9f6..46cd84879c1f 100644
--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -1028,6 +1028,15 @@ static int put_v4l2_ext_controls32(struct file *file,
 	return 0;
 }
 
+#ifdef CONFIG_X86_64
+/*
+ * x86 is the only compat architecture with different struct alignment
+ * between 32-bit and 64-bit tasks.
+ *
+ * On all other architectures, v4l2_event32 and v4l2_event32_time32 are
+ * the same as v4l2_event and v4l2_event_time32, so we can use the native
+ * handlers, converting v4l2_event to v4l2_event_time32 if necessary.
+ */
 struct v4l2_event32 {
 	__u32				type;
 	union {
@@ -1036,7 +1045,20 @@ struct v4l2_event32 {
 	} u;
 	__u32				pending;
 	__u32				sequence;
-	struct compat_timespec		timestamp;
+	struct __kernel_timespec	timestamp;
+	__u32				id;
+	__u32				reserved[8];
+};
+
+struct v4l2_event32_time32 {
+	__u32				type;
+	union {
+		compat_s64		value64;
+		__u8			data[64];
+	} u;
+	__u32				pending;
+	__u32				sequence;
+	struct old_timespec32		timestamp;
 	__u32				id;
 	__u32				reserved[8];
 };
@@ -1057,6 +1079,23 @@ static int put_v4l2_event32(struct v4l2_event __user *p64,
 	return 0;
 }
 
+static int put_v4l2_event32_time32(struct v4l2_event_time32 __user *p64,
+				   struct v4l2_event32_time32 __user *p32)
+{
+	if (!access_ok(p32, sizeof(*p32)) ||
+	    assign_in_user(&p32->type, &p64->type) ||
+	    copy_in_user(&p32->u, &p64->u, sizeof(p64->u)) ||
+	    assign_in_user(&p32->pending, &p64->pending) ||
+	    assign_in_user(&p32->sequence, &p64->sequence) ||
+	    assign_in_user(&p32->timestamp.tv_sec, &p64->timestamp.tv_sec) ||
+	    assign_in_user(&p32->timestamp.tv_nsec, &p64->timestamp.tv_nsec) ||
+	    assign_in_user(&p32->id, &p64->id) ||
+	    copy_in_user(p32->reserved, p64->reserved, sizeof(p32->reserved)))
+		return -EFAULT;
+	return 0;
+}
+#endif
+
 struct v4l2_edid32 {
 	__u32 pad;
 	__u32 start_block;
@@ -1121,6 +1160,7 @@ static int put_v4l2_edid32(struct v4l2_edid __user *p64,
 #define VIDIOC_S_EXT_CTRLS32    _IOWR('V', 72, struct v4l2_ext_controls32)
 #define VIDIOC_TRY_EXT_CTRLS32  _IOWR('V', 73, struct v4l2_ext_controls32)
 #define	VIDIOC_DQEVENT32	_IOR ('V', 89, struct v4l2_event32)
+#define	VIDIOC_DQEVENT32_TIME32	_IOR ('V', 89, struct v4l2_event32_time32)
 #define VIDIOC_CREATE_BUFS32	_IOWR('V', 92, struct v4l2_create_buffers32)
 #define VIDIOC_PREPARE_BUF32	_IOWR('V', 93, struct v4l2_buffer32)
 
@@ -1202,7 +1242,10 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 	case VIDIOC_G_EXT_CTRLS32: ncmd = VIDIOC_G_EXT_CTRLS; break;
 	case VIDIOC_S_EXT_CTRLS32: ncmd = VIDIOC_S_EXT_CTRLS; break;
 	case VIDIOC_TRY_EXT_CTRLS32: ncmd = VIDIOC_TRY_EXT_CTRLS; break;
+#ifdef CONFIG_X86_64
 	case VIDIOC_DQEVENT32: ncmd = VIDIOC_DQEVENT; break;
+	case VIDIOC_DQEVENT32_TIME32: ncmd = VIDIOC_DQEVENT_TIME32; break;
+#endif
 	case VIDIOC_OVERLAY32: ncmd = VIDIOC_OVERLAY; break;
 	case VIDIOC_STREAMON32: ncmd = VIDIOC_STREAMON; break;
 	case VIDIOC_STREAMOFF32: ncmd = VIDIOC_STREAMOFF; break;
@@ -1336,10 +1379,16 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		}
 		compatible_arg = 0;
 		break;
+#ifdef CONFIG_X86_64
 	case VIDIOC_DQEVENT32:
 		err = alloc_userspace(sizeof(struct v4l2_event), 0, &new_p64);
 		compatible_arg = 0;
 		break;
+	case VIDIOC_DQEVENT32_TIME32:
+		err = alloc_userspace(sizeof(struct v4l2_event_time32), 0, &new_p64);
+		compatible_arg = 0;
+		break;
+#endif
 	}
 	if (err)
 		return err;
@@ -1404,10 +1453,16 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		err = put_v4l2_framebuffer32(new_p64, p32);
 		break;
 
+#ifdef CONFIG_X86_64
 	case VIDIOC_DQEVENT32:
 		err = put_v4l2_event32(new_p64, p32);
 		break;
 
+	case VIDIOC_DQEVENT32_TIME32:
+		err = put_v4l2_event32_time32(new_p64, p32);
+		break;
+#endif
+
 	case VIDIOC_G_EDID32:
 		err = put_v4l2_edid32(new_p64, p32);
 		break;
-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5 8/8] media: v4l2-core: fix compat v4l2_buffer handling for time64 ABI
  2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
                   ` (6 preceding siblings ...)
  2019-11-26 16:18 ` [PATCH v5 7/8] media: v4l2-core: fix compat VIDIOC_DQEVENT " Arnd Bergmann
@ 2019-11-26 16:18 ` " Arnd Bergmann
  2019-11-26 19:55 ` [PATCH v5.1 4/8] media: v4l2-core: split out data copy from video_usercopy Arnd Bergmann
  8 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 16:18 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann

Add support for the four new variants of ioctl commands for 64-bit time_t
in v4l2_buffer.

The existing v4l2_buffer32 structure for the traditional format gets
changed to match the new v4l2_buffer format, and the old layout is
now called v4l2_buffer32_time32. Neither of these matches the native
64-bit architecture format of v4l2_buffer, so both require special
handling in compat code.

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.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 265 +++++++++++++++++-
 1 file changed, 264 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
index 46cd84879c1f..3bbf47d950e0 100644
--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -474,7 +474,33 @@ struct v4l2_buffer32 {
 	__u32			bytesused;
 	__u32			flags;
 	__u32			field;	/* enum v4l2_field */
-	struct compat_timeval	timestamp;
+	struct {
+		long long	tv_sec;
+		long long	tv_usec;
+	}			timestamp;
+	struct v4l2_timecode	timecode;
+	__u32			sequence;
+
+	/* memory location */
+	__u32			memory;	/* enum v4l2_memory */
+	union {
+		__u32           offset;
+		compat_long_t   userptr;
+		compat_caddr_t  planes;
+		__s32		fd;
+	} m;
+	__u32			length;
+	__u32			reserved2;
+	__s32			request_fd;
+};
+
+struct v4l2_buffer32_time32 {
+	__u32			index;
+	__u32			type;	/* enum v4l2_buf_type */
+	__u32			bytesused;
+	__u32			flags;
+	__u32			field;	/* enum v4l2_field */
+	struct old_timeval32	timestamp;
 	struct v4l2_timecode	timecode;
 	__u32			sequence;
 
@@ -581,6 +607,31 @@ static int bufsize_v4l2_buffer(struct v4l2_buffer32 __user *p32, u32 *size)
 	return 0;
 }
 
+static int bufsize_v4l2_buffer_time32(struct v4l2_buffer32_time32 __user *p32, u32 *size)
+{
+	u32 type;
+	u32 length;
+
+	if (!access_ok(p32, sizeof(*p32)) ||
+	    get_user(type, &p32->type) ||
+	    get_user(length, &p32->length))
+		return -EFAULT;
+
+	if (V4L2_TYPE_IS_MULTIPLANAR(type)) {
+		if (length > VIDEO_MAX_PLANES)
+			return -EINVAL;
+
+		/*
+		 * We don't really care if userspace decides to kill itself
+		 * by passing a very big length value
+		 */
+		*size = length * sizeof(struct v4l2_plane);
+	} else {
+		*size = 0;
+	}
+	return 0;
+}
+
 static int get_v4l2_buffer32(struct v4l2_buffer __user *p64,
 			     struct v4l2_buffer32 __user *p32,
 			     void __user *aux_buf, u32 aux_space)
@@ -681,6 +732,106 @@ static int get_v4l2_buffer32(struct v4l2_buffer __user *p64,
 	return 0;
 }
 
+static int get_v4l2_buffer32_time32(struct v4l2_buffer_time32 __user *p64,
+				    struct v4l2_buffer32_time32 __user *p32,
+				    void __user *aux_buf, u32 aux_space)
+{
+	u32 type;
+	u32 length;
+	s32 request_fd;
+	enum v4l2_memory memory;
+	struct v4l2_plane32 __user *uplane32;
+	struct v4l2_plane __user *uplane;
+	compat_caddr_t p;
+	int ret;
+
+	if (!access_ok(p32, sizeof(*p32)) ||
+	    assign_in_user(&p64->index, &p32->index) ||
+	    get_user(type, &p32->type) ||
+	    put_user(type, &p64->type) ||
+	    assign_in_user(&p64->flags, &p32->flags) ||
+	    get_user(memory, &p32->memory) ||
+	    put_user(memory, &p64->memory) ||
+	    get_user(length, &p32->length) ||
+	    put_user(length, &p64->length) ||
+	    get_user(request_fd, &p32->request_fd) ||
+	    put_user(request_fd, &p64->request_fd))
+		return -EFAULT;
+
+	if (V4L2_TYPE_IS_OUTPUT(type))
+		if (assign_in_user(&p64->bytesused, &p32->bytesused) ||
+		    assign_in_user(&p64->field, &p32->field) ||
+		    assign_in_user(&p64->timestamp.tv_sec,
+				   &p32->timestamp.tv_sec) ||
+		    assign_in_user(&p64->timestamp.tv_usec,
+				   &p32->timestamp.tv_usec))
+			return -EFAULT;
+
+	if (V4L2_TYPE_IS_MULTIPLANAR(type)) {
+		u32 num_planes = length;
+
+		if (num_planes == 0) {
+			/*
+			 * num_planes == 0 is legal, e.g. when userspace doesn't
+			 * need planes array on DQBUF
+			 */
+			return put_user(NULL, &p64->m.planes);
+		}
+		if (num_planes > VIDEO_MAX_PLANES)
+			return -EINVAL;
+
+		if (get_user(p, &p32->m.planes))
+			return -EFAULT;
+
+		uplane32 = compat_ptr(p);
+		if (!access_ok(uplane32,
+			       num_planes * sizeof(*uplane32)))
+			return -EFAULT;
+
+		/*
+		 * We don't really care if userspace decides to kill itself
+		 * by passing a very big num_planes value
+		 */
+		if (aux_space < num_planes * sizeof(*uplane))
+			return -EFAULT;
+
+		uplane = aux_buf;
+		if (put_user_force(uplane, &p64->m.planes))
+			return -EFAULT;
+
+		while (num_planes--) {
+			ret = get_v4l2_plane32(uplane, uplane32, memory);
+			if (ret)
+				return ret;
+			uplane++;
+			uplane32++;
+		}
+	} else {
+		switch (memory) {
+		case V4L2_MEMORY_MMAP:
+		case V4L2_MEMORY_OVERLAY:
+			if (assign_in_user(&p64->m.offset, &p32->m.offset))
+				return -EFAULT;
+			break;
+		case V4L2_MEMORY_USERPTR: {
+			compat_ulong_t userptr;
+
+			if (get_user(userptr, &p32->m.userptr) ||
+			    put_user((unsigned long)compat_ptr(userptr),
+				     &p64->m.userptr))
+				return -EFAULT;
+			break;
+		}
+		case V4L2_MEMORY_DMABUF:
+			if (assign_in_user(&p64->m.fd, &p32->m.fd))
+				return -EFAULT;
+			break;
+		}
+	}
+
+	return 0;
+}
+
 static int put_v4l2_buffer32(struct v4l2_buffer __user *p64,
 			     struct v4l2_buffer32 __user *p32)
 {
@@ -761,6 +912,87 @@ static int put_v4l2_buffer32(struct v4l2_buffer __user *p64,
 	return 0;
 }
 
+
+static int put_v4l2_buffer32_time32(struct v4l2_buffer_time32 __user *p64,
+				    struct v4l2_buffer32_time32 __user *p32)
+{
+	u32 type;
+	u32 length;
+	enum v4l2_memory memory;
+	struct v4l2_plane32 __user *uplane32;
+	struct v4l2_plane *uplane;
+	compat_caddr_t p;
+	int ret;
+
+	if (!access_ok(p32, sizeof(*p32)) ||
+	    assign_in_user(&p32->index, &p64->index) ||
+	    get_user(type, &p64->type) ||
+	    put_user(type, &p32->type) ||
+	    assign_in_user(&p32->flags, &p64->flags) ||
+	    get_user(memory, &p64->memory) ||
+	    put_user(memory, &p32->memory))
+		return -EFAULT;
+
+	if (assign_in_user(&p32->bytesused, &p64->bytesused) ||
+	    assign_in_user(&p32->field, &p64->field) ||
+	    assign_in_user(&p32->timestamp.tv_sec, &p64->timestamp.tv_sec) ||
+	    assign_in_user(&p32->timestamp.tv_usec, &p64->timestamp.tv_usec) ||
+	    copy_in_user(&p32->timecode, &p64->timecode, sizeof(p64->timecode)) ||
+	    assign_in_user(&p32->sequence, &p64->sequence) ||
+	    assign_in_user(&p32->reserved2, &p64->reserved2) ||
+	    assign_in_user(&p32->request_fd, &p64->request_fd) ||
+	    get_user(length, &p64->length) ||
+	    put_user(length, &p32->length))
+		return -EFAULT;
+
+	if (V4L2_TYPE_IS_MULTIPLANAR(type)) {
+		u32 num_planes = length;
+
+		if (num_planes == 0)
+			return 0;
+		/* We need to define uplane without __user, even though
+		 * it does point to data in userspace here. The reason is
+		 * that v4l2-ioctl.c copies it from userspace to kernelspace,
+		 * so its definition in videodev2.h doesn't have a
+		 * __user markup. Defining uplane with __user causes
+		 * smatch warnings, so instead declare it without __user
+		 * and cast it as a userspace pointer to put_v4l2_plane32().
+		 */
+		if (get_user(uplane, &p64->m.planes))
+			return -EFAULT;
+		if (get_user(p, &p32->m.planes))
+			return -EFAULT;
+		uplane32 = compat_ptr(p);
+
+		while (num_planes--) {
+			ret = put_v4l2_plane32((void __user *)uplane,
+					       uplane32, memory);
+			if (ret)
+				return ret;
+			++uplane;
+			++uplane32;
+		}
+	} else {
+		switch (memory) {
+		case V4L2_MEMORY_MMAP:
+		case V4L2_MEMORY_OVERLAY:
+			if (assign_in_user(&p32->m.offset, &p64->m.offset))
+				return -EFAULT;
+			break;
+		case V4L2_MEMORY_USERPTR:
+			if (assign_in_user(&p32->m.userptr, &p64->m.userptr))
+				return -EFAULT;
+			break;
+		case V4L2_MEMORY_DMABUF:
+			if (assign_in_user(&p32->m.fd, &p64->m.fd))
+				return -EFAULT;
+			break;
+		}
+	}
+
+	return 0;
+}
+
 struct v4l2_framebuffer32 {
 	__u32			capability;
 	__u32			flags;
@@ -1147,10 +1379,13 @@ static int put_v4l2_edid32(struct v4l2_edid __user *p64,
 #define VIDIOC_G_FMT32		_IOWR('V',  4, struct v4l2_format32)
 #define VIDIOC_S_FMT32		_IOWR('V',  5, struct v4l2_format32)
 #define VIDIOC_QUERYBUF32	_IOWR('V',  9, struct v4l2_buffer32)
+#define VIDIOC_QUERYBUF32_TIME32 _IOWR('V',  9, struct v4l2_buffer32_time32)
 #define VIDIOC_G_FBUF32		_IOR ('V', 10, struct v4l2_framebuffer32)
 #define VIDIOC_S_FBUF32		_IOW ('V', 11, struct v4l2_framebuffer32)
 #define VIDIOC_QBUF32		_IOWR('V', 15, struct v4l2_buffer32)
+#define VIDIOC_QBUF32_TIME32	_IOWR('V', 15, struct v4l2_buffer32_time32)
 #define VIDIOC_DQBUF32		_IOWR('V', 17, struct v4l2_buffer32)
+#define VIDIOC_DQBUF32_TIME32	_IOWR('V', 17, struct v4l2_buffer32_time32)
 #define VIDIOC_ENUMSTD32	_IOWR('V', 25, struct v4l2_standard32)
 #define VIDIOC_ENUMINPUT32	_IOWR('V', 26, struct v4l2_input32)
 #define VIDIOC_G_EDID32		_IOWR('V', 40, struct v4l2_edid32)
@@ -1163,6 +1398,7 @@ static int put_v4l2_edid32(struct v4l2_edid __user *p64,
 #define	VIDIOC_DQEVENT32_TIME32	_IOR ('V', 89, struct v4l2_event32_time32)
 #define VIDIOC_CREATE_BUFS32	_IOWR('V', 92, struct v4l2_create_buffers32)
 #define VIDIOC_PREPARE_BUF32	_IOWR('V', 93, struct v4l2_buffer32)
+#define VIDIOC_PREPARE_BUF32_TIME32 _IOWR('V', 93, struct v4l2_buffer32_time32)
 
 #define VIDIOC_OVERLAY32	_IOW ('V', 14, s32)
 #define VIDIOC_STREAMON32	_IOW ('V', 18, s32)
@@ -1232,10 +1468,13 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 	case VIDIOC_G_FMT32: ncmd = VIDIOC_G_FMT; break;
 	case VIDIOC_S_FMT32: ncmd = VIDIOC_S_FMT; break;
 	case VIDIOC_QUERYBUF32: ncmd = VIDIOC_QUERYBUF; break;
+	case VIDIOC_QUERYBUF32_TIME32: ncmd = VIDIOC_QUERYBUF_TIME32; break;
 	case VIDIOC_G_FBUF32: ncmd = VIDIOC_G_FBUF; break;
 	case VIDIOC_S_FBUF32: ncmd = VIDIOC_S_FBUF; break;
 	case VIDIOC_QBUF32: ncmd = VIDIOC_QBUF; break;
+	case VIDIOC_QBUF32_TIME32: ncmd = VIDIOC_QBUF_TIME32; break;
 	case VIDIOC_DQBUF32: ncmd = VIDIOC_DQBUF; break;
+	case VIDIOC_DQBUF32_TIME32: ncmd = VIDIOC_DQBUF_TIME32; break;
 	case VIDIOC_ENUMSTD32: ncmd = VIDIOC_ENUMSTD; break;
 	case VIDIOC_ENUMINPUT32: ncmd = VIDIOC_ENUMINPUT; break;
 	case VIDIOC_TRY_FMT32: ncmd = VIDIOC_TRY_FMT; break;
@@ -1255,6 +1494,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 	case VIDIOC_S_OUTPUT32: ncmd = VIDIOC_S_OUTPUT; break;
 	case VIDIOC_CREATE_BUFS32: ncmd = VIDIOC_CREATE_BUFS; break;
 	case VIDIOC_PREPARE_BUF32: ncmd = VIDIOC_PREPARE_BUF; break;
+	case VIDIOC_PREPARE_BUF32_TIME32: ncmd = VIDIOC_PREPARE_BUF_TIME32; break;
 	case VIDIOC_G_EDID32: ncmd = VIDIOC_G_EDID; break;
 	case VIDIOC_S_EDID32: ncmd = VIDIOC_S_EDID; break;
 	default: ncmd = cmd; break;
@@ -1336,6 +1576,22 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		compatible_arg = 0;
 		break;
 
+	case VIDIOC_PREPARE_BUF32_TIME32:
+	case VIDIOC_QUERYBUF32_TIME32:
+	case VIDIOC_QBUF32_TIME32:
+	case VIDIOC_DQBUF32_TIME32:
+		err = bufsize_v4l2_buffer_time32(p32, &aux_space);
+		if (!err)
+			err = alloc_userspace(sizeof(struct v4l2_buffer),
+					      aux_space, &new_p64);
+		if (!err) {
+			aux_buf = new_p64 + sizeof(struct v4l2_buffer);
+			err = get_v4l2_buffer32_time32(new_p64, p32,
+						       aux_buf, aux_space);
+		}
+		compatible_arg = 0;
+		break;
+
 	case VIDIOC_S_FBUF32:
 		err = alloc_userspace(sizeof(struct v4l2_framebuffer), 0,
 				      &new_p64);
@@ -1484,6 +1740,13 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
 		err = put_v4l2_buffer32(new_p64, p32);
 		break;
 
+	case VIDIOC_PREPARE_BUF32_TIME32:
+	case VIDIOC_QUERYBUF32_TIME32:
+	case VIDIOC_QBUF32_TIME32:
+	case VIDIOC_DQBUF32_TIME32:
+		err = put_v4l2_buffer32_time32(new_p64, p32);
+		break;
+
 	case VIDIOC_ENUMSTD32:
 		err = put_v4l2_standard32(new_p64, p32);
 		break;
-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5.1 4/8] media: v4l2-core: split out data copy from video_usercopy
  2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
                   ` (7 preceding siblings ...)
  2019-11-26 16:18 ` [PATCH v5 8/8] media: v4l2-core: fix compat v4l2_buffer handling " Arnd Bergmann
@ 2019-11-26 19:55 ` Arnd Bergmann
  8 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2019-11-26 19:55 UTC (permalink / raw)
  To: linux-media, Hans Verkuil, Mauro Carvalho Chehab
  Cc: y2038, linux-kernel, Arnd Bergmann

The copy-in/out portions of video_usercopy() are about to
get more complex, so turn then into separate functions as
a cleanup first.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
v5.1: fix error handling for positive return code

 drivers/media/v4l2-core/v4l2-ioctl.c | 108 +++++++++++++++++----------
 1 file changed, 69 insertions(+), 39 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 4e700583659b..fe4678965e1b 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -3023,8 +3023,69 @@ static int check_array_args(unsigned int cmd, void *parg, size_t *array_size,
 	return ret;
 }
 
+static unsigned int video_translate_cmd(unsigned int cmd)
+{
+	return cmd;
+}
+
+static int video_get_user(void __user *arg, void *parg, unsigned int cmd,
+			  bool *always_copy)
+{
+	unsigned int n = _IOC_SIZE(cmd);
+
+	if (!(_IOC_DIR(cmd) & _IOC_WRITE)) {
+		/* read-only ioctl */
+		memset(parg, 0, n);
+		return 0;
+	}
+
+	switch (cmd) {
+	default:
+		/*
+		 * In some cases, only a few fields are used as input,
+		 * i.e. when the app sets "index" and then the driver
+		 * fills in the rest of the structure for the thing
+		 * with that index.  We only need to copy up the first
+		 * non-input field.
+		 */
+		if (v4l2_is_known_ioctl(cmd)) {
+			u32 flags = v4l2_ioctls[_IOC_NR(cmd)].flags;
+
+			if (flags & INFO_FL_CLEAR_MASK)
+				n = (flags & INFO_FL_CLEAR_MASK) >> 16;
+			*always_copy = flags & INFO_FL_ALWAYS_COPY;
+		}
+
+		if (copy_from_user(parg, (void __user *)arg, n))
+			return -EFAULT;
+
+		/* zero out anything we don't copy from userspace */
+		if (n < _IOC_SIZE(cmd))
+			memset((u8 *)parg + n, 0, _IOC_SIZE(cmd) - n);
+		break;
+	}
+
+	return 0;
+}
+
+static int video_put_user(void __user *arg, void *parg, unsigned int cmd)
+{
+	if (!(_IOC_DIR(cmd) & _IOC_READ))
+		return 0;
+
+	switch (cmd) {
+	default:
+		/*  Copy results into user buffer  */
+		if (copy_to_user(arg, parg, _IOC_SIZE(cmd)))
+			return -EFAULT;
+		break;
+	}
+
+	return 0;
+}
+
 long
-video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
+video_usercopy(struct file *file, unsigned int orig_cmd, unsigned long arg,
 	       v4l2_kioctl func)
 {
 	char	sbuf[128];
@@ -3036,6 +3097,7 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
 	size_t  array_size = 0;
 	void __user *user_ptr = NULL;
 	void	**kernel_ptr = NULL;
+	unsigned int cmd = video_translate_cmd(orig_cmd);
 	const size_t ioc_size = _IOC_SIZE(cmd);
 
 	/*  Copy arguments into temp kernel buffer  */
@@ -3050,37 +3112,12 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
 			parg = mbuf;
 		}
 
-		err = -EFAULT;
-		if (_IOC_DIR(cmd) & _IOC_WRITE) {
-			unsigned int n = ioc_size;
-
-			/*
-			 * In some cases, only a few fields are used as input,
-			 * i.e. when the app sets "index" and then the driver
-			 * fills in the rest of the structure for the thing
-			 * with that index.  We only need to copy up the first
-			 * non-input field.
-			 */
-			if (v4l2_is_known_ioctl(cmd)) {
-				u32 flags = v4l2_ioctls[_IOC_NR(cmd)].flags;
-
-				if (flags & INFO_FL_CLEAR_MASK)
-					n = (flags & INFO_FL_CLEAR_MASK) >> 16;
-				always_copy = flags & INFO_FL_ALWAYS_COPY;
-			}
-
-			if (copy_from_user(parg, (void __user *)arg, n))
-				goto out;
-
-			/* zero out anything we don't copy from userspace */
-			if (n < ioc_size)
-				memset((u8 *)parg + n, 0, ioc_size - n);
-		} else {
-			/* read-only ioctl */
-			memset(parg, 0, ioc_size);
-		}
 	}
 
+	err = video_get_user((void __user *)arg, parg, orig_cmd, &always_copy);
+	if (err)
+		goto out;
+
 	err = check_array_args(cmd, parg, &array_size, &user_ptr, &kernel_ptr);
 	if (err < 0)
 		goto out;
@@ -3131,15 +3168,8 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
 		goto out;
 
 out_array_args:
-	/*  Copy results into user buffer  */
-	switch (_IOC_DIR(cmd)) {
-	case _IOC_READ:
-	case (_IOC_WRITE | _IOC_READ):
-		if (copy_to_user((void __user *)arg, parg, ioc_size))
-			err = -EFAULT;
-		break;
-	}
-
+	if (video_put_user((void __user *)arg, parg, orig_cmd))
+		err = -EFAULT;
 out:
 	kvfree(mbuf);
 	return err;
-- 
2.20.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, back to index

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-11-26 16:18 [PATCH v5 0/8] y2038 safety in v4l2 Arnd Bergmann
2019-11-26 16:18 ` [PATCH v5 1/8] media: documentation: fix video_event description Arnd Bergmann
2019-11-26 16:18 ` [PATCH v5 2/8] media: v4l2: abstract timeval handling in v4l2_buffer Arnd Bergmann
2019-11-26 16:18 ` [PATCH v5 3/8] media: v4l2-core: compat: ignore native command codes Arnd Bergmann
2019-11-26 16:18 ` [PATCH v5 4/8] media: v4l2-core: split out data copy from video_usercopy Arnd Bergmann
2019-11-26 16:18 ` [PATCH v5 5/8] media: v4l2-core: fix VIDIOC_DQEVENT for time64 ABI Arnd Bergmann
2019-11-26 16:18 ` [PATCH v5 6/8] media: v4l2-core: fix v4l2_buffer handling " Arnd Bergmann
2019-11-26 16:18 ` [PATCH v5 7/8] media: v4l2-core: fix compat VIDIOC_DQEVENT " Arnd Bergmann
2019-11-26 16:18 ` [PATCH v5 8/8] media: v4l2-core: fix compat v4l2_buffer handling " Arnd Bergmann
2019-11-26 19:55 ` [PATCH v5.1 4/8] media: v4l2-core: split out data copy from video_usercopy Arnd Bergmann

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Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-media


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git