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.

Signed-off-by: Arnd Bergmann <[email protected]>
---
 drivers/media/v4l2-core/v4l2-ioctl.c | 57 ++++++++++++++++++++++++++--
 include/uapi/linux/videodev2.h       | 40 +++++++++++++++++++
 2 files changed, 93 insertions(+), 4 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c 
b/drivers/media/v4l2-core/v4l2-ioctl.c
index b8aca0d174bd..cd9a80960289 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("%02ld:%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 +3055,30 @@ 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;
+
+               memcpy(vb, &vb32, offsetof(struct v4l2_buffer, timestamp));
+               vb->timestamp.tv_sec = vb32.timestamp.tv_sec;
+               vb->timestamp.tv_usec = vb32.timestamp.tv_usec;
+               memcpy(&vb->timecode, &vb32.timecode,
+                      sizeof(*vb) - offsetof(struct v4l2_buffer, timecode));
+
+               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,
@@ -3095,6 +3127,23 @@ 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_time32 vb32;
+               struct v4l2_buffer *vb = parg;
+
+               memcpy(&vb32, vb, offsetof(struct v4l2_buffer, timestamp));
+               vb32.timestamp.tv_sec = vb->timestamp.tv_sec;
+               vb32.timestamp.tv_usec = vb->timestamp.tv_usec;
+               memcpy(&vb32.timecode, &vb->timecode,
+                      sizeof(*vb) - offsetof(struct v4l2_buffer, timecode));
+
+               if (copy_to_user(arg, &vb32, sizeof(vb32)))
+                       return -EFAULT;
+               break;
+       }
 #endif
        default:
                /*  Copy results into user buffer  */
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index e38afa71a327..4275d6e92dae 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -997,7 +997,42 @@ struct v4l2_buffer {
        __u32                   bytesused;
        __u32                   flags;
        __u32                   field;
+#ifdef __KERNEL__
+       /* match glibc timeval64 format */
+       struct {
+               long long       tv_sec;
+               long long       tv_usec;
+       } timestamp;
+#else
        struct timeval          timestamp;
+#endif
+       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;
+       };
+};
+
+#ifdef __KERNEL__
+struct v4l2_buffer_time32 {
+       __u32                   index;
+       __u32                   type;
+       __u32                   bytesused;
+       __u32                   flags;
+       __u32                   field;
+       struct old_timeval32    timestamp;
        struct v4l2_timecode    timecode;
        __u32                   sequence;
 
@@ -1016,6 +1051,7 @@ struct v4l2_buffer {
                __u32           reserved;
        };
 };
+#endif
 
 #ifndef __KERNEL__
 /**
@@ -2457,12 +2493,15 @@ struct v4l2_create_buffers {
 #define VIDIOC_S_FMT           _IOWR('V',  5, struct v4l2_format)
 #define VIDIOC_REQBUFS         _IOWR('V',  8, struct v4l2_requestbuffers)
 #define VIDIOC_QUERYBUF                _IOWR('V',  9, struct v4l2_buffer)
+#define VIDIOC_QUERYBUF_TIME32 _IOWR('V',  9, struct v4l2_buffer_time32)
 #define VIDIOC_G_FBUF           _IOR('V', 10, struct v4l2_framebuffer)
 #define VIDIOC_S_FBUF           _IOW('V', 11, struct v4l2_framebuffer)
 #define VIDIOC_OVERLAY          _IOW('V', 14, int)
 #define VIDIOC_QBUF            _IOWR('V', 15, struct v4l2_buffer)
+#define VIDIOC_QBUF_TIME32     _IOWR('V', 15, struct v4l2_buffer_time32)
 #define VIDIOC_EXPBUF          _IOWR('V', 16, struct v4l2_exportbuffer)
 #define VIDIOC_DQBUF           _IOWR('V', 17, struct v4l2_buffer)
+#define VIDIOC_DQBUF_TIME32    _IOWR('V', 17, struct v4l2_buffer_time32)
 #define VIDIOC_STREAMON                 _IOW('V', 18, int)
 #define VIDIOC_STREAMOFF        _IOW('V', 19, int)
 #define VIDIOC_G_PARM          _IOWR('V', 21, struct v4l2_streamparm)
@@ -2531,6 +2570,7 @@ struct v4l2_create_buffers {
 #define        VIDIOC_UNSUBSCRIBE_EVENT _IOW('V', 91, struct 
v4l2_event_subscription)
 #define VIDIOC_CREATE_BUFS     _IOWR('V', 92, struct v4l2_create_buffers)
 #define VIDIOC_PREPARE_BUF     _IOWR('V', 93, struct v4l2_buffer)
+#define VIDIOC_PREPARE_BUF_TIME32 _IOWR('V', 93, struct v4l2_buffer_time32)
 #define VIDIOC_G_SELECTION     _IOWR('V', 94, struct v4l2_selection)
 #define VIDIOC_S_SELECTION     _IOWR('V', 95, struct v4l2_selection)
 #define VIDIOC_DECODER_CMD     _IOWR('V', 96, struct v4l2_decoder_cmd)
-- 
2.20.0

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