This change fixes indirect call mismatches with Control-Flow Integrity
checking, which are caused by calling standard ioctls using a function
pointer that doesn't match the type of the actual function.

Signed-off-by: Sami Tolvanen <samitolva...@google.com>
---
 drivers/media/v4l2-core/v4l2-ioctl.c | 72 ++++++++++++++++++----------
 1 file changed, 46 insertions(+), 26 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c 
b/drivers/media/v4l2-core/v4l2-ioctl.c
index f48c505550e0..d50a06ab3509 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -2489,11 +2489,8 @@ struct v4l2_ioctl_info {
        unsigned int ioctl;
        u32 flags;
        const char * const name;
-       union {
-               u32 offset;
-               int (*func)(const struct v4l2_ioctl_ops *ops,
-                               struct file *file, void *fh, void *p);
-       } u;
+       int (*func)(const struct v4l2_ioctl_ops *ops, struct file *file,
+                   void *fh, void *p);
        void (*debug)(const void *arg, bool write_only);
 };
 
@@ -2501,27 +2498,24 @@ struct v4l2_ioctl_info {
 #define INFO_FL_PRIO           (1 << 0)
 /* This control can be valid if the filehandle passes a control handler. */
 #define INFO_FL_CTRL           (1 << 1)
-/* This is a standard ioctl, no need for special code */
-#define INFO_FL_STD            (1 << 2)
 /* This is ioctl has its own function */
-#define INFO_FL_FUNC           (1 << 3)
+#define INFO_FL_FUNC           (1 << 2)
 /* Queuing ioctl */
-#define INFO_FL_QUEUE          (1 << 4)
+#define INFO_FL_QUEUE          (1 << 3)
 /* Always copy back result, even on error */
-#define INFO_FL_ALWAYS_COPY    (1 << 5)
+#define INFO_FL_ALWAYS_COPY    (1 << 4)
 /* Zero struct from after the field to the end */
 #define INFO_FL_CLEAR(v4l2_struct, field)                      \
        ((offsetof(struct v4l2_struct, field) +                 \
          sizeof(((struct v4l2_struct *)0)->field)) << 16)
 #define INFO_FL_CLEAR_MASK     (_IOC_SIZEMASK << 16)
 
-#define IOCTL_INFO_STD(_ioctl, _vidioc, _debug, _flags)                        
\
-       [_IOC_NR(_ioctl)] = {                                           \
-               .ioctl = _ioctl,                                        \
-               .flags = _flags | INFO_FL_STD,                          \
-               .name = #_ioctl,                                        \
-               .u.offset = offsetof(struct v4l2_ioctl_ops, _vidioc),   \
-               .debug = _debug,                                        \
+#define DEFINE_IOCTL_STD_FNC(_vidioc)                          \
+       static int __v4l_ ## _vidioc ## _fnc(                   \
+                       const struct v4l2_ioctl_ops *ops,       \
+                       struct file *file, void *fh, void *p)   \
+       {                                                       \
+               return ops->_vidioc(file, fh, p);               \
        }
 
 #define IOCTL_INFO_FNC(_ioctl, _func, _debug, _flags)                  \
@@ -2529,10 +2523,42 @@ struct v4l2_ioctl_info {
                .ioctl = _ioctl,                                        \
                .flags = _flags | INFO_FL_FUNC,                         \
                .name = #_ioctl,                                        \
-               .u.func = _func,                                        \
+               .func = _func,                                          \
                .debug = _debug,                                        \
        }
 
+#define IOCTL_INFO_STD(_ioctl, _vidioc, _debug, _flags)        \
+       IOCTL_INFO_FNC(_ioctl, __v4l_ ## _vidioc ## _fnc, _debug, _flags)
+
+DEFINE_IOCTL_STD_FNC(vidioc_g_fbuf)
+DEFINE_IOCTL_STD_FNC(vidioc_s_fbuf)
+DEFINE_IOCTL_STD_FNC(vidioc_expbuf)
+DEFINE_IOCTL_STD_FNC(vidioc_g_std)
+DEFINE_IOCTL_STD_FNC(vidioc_g_audio)
+DEFINE_IOCTL_STD_FNC(vidioc_s_audio)
+DEFINE_IOCTL_STD_FNC(vidioc_g_input)
+DEFINE_IOCTL_STD_FNC(vidioc_g_edid)
+DEFINE_IOCTL_STD_FNC(vidioc_s_edid)
+DEFINE_IOCTL_STD_FNC(vidioc_g_output)
+DEFINE_IOCTL_STD_FNC(vidioc_g_audout)
+DEFINE_IOCTL_STD_FNC(vidioc_s_audout)
+DEFINE_IOCTL_STD_FNC(vidioc_g_jpegcomp)
+DEFINE_IOCTL_STD_FNC(vidioc_s_jpegcomp)
+DEFINE_IOCTL_STD_FNC(vidioc_enumaudio)
+DEFINE_IOCTL_STD_FNC(vidioc_enumaudout)
+DEFINE_IOCTL_STD_FNC(vidioc_enum_framesizes)
+DEFINE_IOCTL_STD_FNC(vidioc_enum_frameintervals)
+DEFINE_IOCTL_STD_FNC(vidioc_g_enc_index)
+DEFINE_IOCTL_STD_FNC(vidioc_encoder_cmd)
+DEFINE_IOCTL_STD_FNC(vidioc_try_encoder_cmd)
+DEFINE_IOCTL_STD_FNC(vidioc_decoder_cmd)
+DEFINE_IOCTL_STD_FNC(vidioc_try_decoder_cmd)
+DEFINE_IOCTL_STD_FNC(vidioc_s_dv_timings)
+DEFINE_IOCTL_STD_FNC(vidioc_g_dv_timings)
+DEFINE_IOCTL_STD_FNC(vidioc_enum_dv_timings)
+DEFINE_IOCTL_STD_FNC(vidioc_query_dv_timings)
+DEFINE_IOCTL_STD_FNC(vidioc_dv_timings_cap)
+
 static struct v4l2_ioctl_info v4l2_ioctls[] = {
        IOCTL_INFO_FNC(VIDIOC_QUERYCAP, v4l_querycap, v4l_print_querycap, 0),
        IOCTL_INFO_FNC(VIDIOC_ENUM_FMT, v4l_enum_fmt, v4l_print_fmtdesc, 
INFO_FL_CLEAR(v4l2_fmtdesc, type)),
@@ -2717,14 +2743,8 @@ static long __video_do_ioctl(struct file *file,
        }
 
        write_only = _IOC_DIR(cmd) == _IOC_WRITE;
-       if (info->flags & INFO_FL_STD) {
-               typedef int (*vidioc_op)(struct file *file, void *fh, void *p);
-               const void *p = vfd->ioctl_ops;
-               const vidioc_op *vidioc = p + info->u.offset;
-
-               ret = (*vidioc)(file, fh, arg);
-       } else if (info->flags & INFO_FL_FUNC) {
-               ret = info->u.func(ops, file, fh, arg);
+       if (info->flags & INFO_FL_FUNC) {
+               ret = info->func(ops, file, fh, arg);
        } else if (!ops->vidioc_default) {
                ret = -ENOTTY;
        } else {
-- 
2.17.0.441.gb46fe60e1d-goog

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