The two functions are mostly identical. They handle the copy_from_user
and copy_to_user operations related with V4L2 ioctls and call the real
ioctl handler.
Create a __video_usercopy function that implements the core of
video_usercopy and video_ioctl2, and call that function from both.
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/media/video/v4l2-ioctl.c | 218 ++++++++++++-------------------------
1 files changed, 71 insertions(+), 147 deletions(-)
diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c
index dd9283f..1e01554 100644
--- a/drivers/media/video/v4l2-ioctl.c
+++ b/drivers/media/video/v4l2-ioctl.c
@@ -374,35 +374,62 @@ video_fix_command(unsigned int cmd)
}
#endif
-/*
- * Obsolete usercopy function - Should be removed soon
- */
-long
-video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
+/* 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. */
+static unsigned long cmd_input_size(unsigned int cmd)
+{
+ /* Size of structure up to and including 'field' */
+#define CMDINSIZE(cmd, type, field) \
+ case VIDIOC_##cmd: \
+ return offsetof(struct v4l2_##type, field) + \
+ sizeof(((struct v4l2_##type *)0)->field);
+
+ switch (cmd) {
+ CMDINSIZE(ENUM_FMT, fmtdesc, type);
+ CMDINSIZE(G_FMT, format, type);
+ CMDINSIZE(QUERYBUF, buffer, type);
+ CMDINSIZE(G_PARM, streamparm, type);
+ CMDINSIZE(ENUMSTD, standard, index);
+ CMDINSIZE(ENUMINPUT, input, index);
+ CMDINSIZE(G_CTRL, control, id);
+ CMDINSIZE(G_TUNER, tuner, index);
+ CMDINSIZE(QUERYCTRL, queryctrl, id);
+ CMDINSIZE(QUERYMENU, querymenu, index);
+ CMDINSIZE(ENUMOUTPUT, output, index);
+ CMDINSIZE(G_MODULATOR, modulator, index);
+ CMDINSIZE(G_FREQUENCY, frequency, tuner);
+ CMDINSIZE(CROPCAP, cropcap, type);
+ CMDINSIZE(G_CROP, crop, type);
+ CMDINSIZE(ENUMAUDIO, audio, index);
+ CMDINSIZE(ENUMAUDOUT, audioout, index);
+ CMDINSIZE(ENCODER_CMD, encoder_cmd, flags);
+ CMDINSIZE(TRY_ENCODER_CMD, encoder_cmd, flags);
+ CMDINSIZE(G_SLICED_VBI_CAP, sliced_vbi_cap, type);
+ CMDINSIZE(ENUM_FRAMESIZES, frmsizeenum, pixel_format);
+ CMDINSIZE(ENUM_FRAMEINTERVALS, frmivalenum, height);
+ default:
+ return _IOC_SIZE(cmd);
+ }
+}
+
+static long
+__video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
v4l2_kioctl func)
{
char sbuf[128];
void *mbuf = NULL;
- void *parg = NULL;
+ void *parg = (void *)arg;
long err = -EINVAL;
int is_ext_ctrl;
size_t ctrls_size = 0;
void __user *user_ptr = NULL;
-#ifdef __OLD_VIDIOC_
- cmd = video_fix_command(cmd);
-#endif
is_ext_ctrl = (cmd == VIDIOC_S_EXT_CTRLS || cmd == VIDIOC_G_EXT_CTRLS ||
cmd == VIDIOC_TRY_EXT_CTRLS);
/* Copy arguments into temp kernel buffer */
- switch (_IOC_DIR(cmd)) {
- case _IOC_NONE:
- parg = NULL;
- break;
- case _IOC_READ:
- case _IOC_WRITE:
- case (_IOC_WRITE | _IOC_READ):
+ if (_IOC_DIR(cmd) != _IOC_NONE) {
if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
parg = sbuf;
} else {
@@ -414,11 +441,21 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
}
err = -EFAULT;
- if (_IOC_DIR(cmd) & _IOC_WRITE)
- if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
+ if (_IOC_DIR(cmd) & _IOC_WRITE) {
+ unsigned long n = cmd_input_size(cmd);
+
+ if (copy_from_user(parg, (void __user *)arg, n))
goto out;
- break;
+
+ /* zero out anything we don't copy from userspace */
+ if (n < _IOC_SIZE(cmd))
+ memset((u8 *)parg + n, 0, _IOC_SIZE(cmd) - n);
+ } else {
+ /* read-only ioctl */
+ memset(parg, 0, _IOC_SIZE(cmd));
+ }
}
+
if (is_ext_ctrl) {
struct v4l2_ext_controls *p = parg;
@@ -440,7 +477,7 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
}
}
- /* call driver */
+ /* Handles IOCTL */
err = func(file, cmd, parg);
if (err == -ENOIOCTLCMD)
err = -EINVAL;
@@ -469,6 +506,19 @@ out:
kfree(mbuf);
return err;
}
+
+/*
+ * Obsolete usercopy function - Should be removed soon
+ */
+long
+video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
+ v4l2_kioctl func)
+{
+#ifdef __OLD_VIDIOC_
+ cmd = video_fix_command(cmd);
+#endif
+ return __video_usercopy(file, cmd, arg, func);
+}
EXPORT_SYMBOL(video_usercopy);
static void dbgbuf(unsigned int cmd, struct video_device *vfd,
@@ -2041,138 +2091,12 @@ static long __video_do_ioctl(struct file *file,
return ret;
}
-/* 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. */
-static unsigned long cmd_input_size(unsigned int cmd)
-{
- /* Size of structure up to and including 'field' */
-#define CMDINSIZE(cmd, type, field) \
- case VIDIOC_##cmd: \
- return offsetof(struct v4l2_##type, field) + \
- sizeof(((struct v4l2_##type *)0)->field);
-
- switch (cmd) {
- CMDINSIZE(ENUM_FMT, fmtdesc, type);
- CMDINSIZE(G_FMT, format, type);
- CMDINSIZE(QUERYBUF, buffer, type);
- CMDINSIZE(G_PARM, streamparm, type);
- CMDINSIZE(ENUMSTD, standard, index);
- CMDINSIZE(ENUMINPUT, input, index);
- CMDINSIZE(G_CTRL, control, id);
- CMDINSIZE(G_TUNER, tuner, index);
- CMDINSIZE(QUERYCTRL, queryctrl, id);
- CMDINSIZE(QUERYMENU, querymenu, index);
- CMDINSIZE(ENUMOUTPUT, output, index);
- CMDINSIZE(G_MODULATOR, modulator, index);
- CMDINSIZE(G_FREQUENCY, frequency, tuner);
- CMDINSIZE(CROPCAP, cropcap, type);
- CMDINSIZE(G_CROP, crop, type);
- CMDINSIZE(ENUMAUDIO, audio, index);
- CMDINSIZE(ENUMAUDOUT, audioout, index);
- CMDINSIZE(ENCODER_CMD, encoder_cmd, flags);
- CMDINSIZE(TRY_ENCODER_CMD, encoder_cmd, flags);
- CMDINSIZE(G_SLICED_VBI_CAP, sliced_vbi_cap, type);
- CMDINSIZE(ENUM_FRAMESIZES, frmsizeenum, pixel_format);
- CMDINSIZE(ENUM_FRAMEINTERVALS, frmivalenum, height);
- default:
- return _IOC_SIZE(cmd);
- }
-}
-
long video_ioctl2(struct file *file,
unsigned int cmd, unsigned long arg)
{
- char sbuf[128];
- void *mbuf = NULL;
- void *parg = (void *)arg;
- long err = -EINVAL;
- int is_ext_ctrl;
- size_t ctrls_size = 0;
- void __user *user_ptr = NULL;
-
#ifdef __OLD_VIDIOC_
cmd = video_fix_command(cmd);
#endif
- is_ext_ctrl = (cmd == VIDIOC_S_EXT_CTRLS || cmd == VIDIOC_G_EXT_CTRLS ||
- cmd == VIDIOC_TRY_EXT_CTRLS);
-
- /* Copy arguments into temp kernel buffer */
- if (_IOC_DIR(cmd) != _IOC_NONE) {
- if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
- parg = sbuf;
- } else {
- /* too big to allocate from stack */
- mbuf = kmalloc(_IOC_SIZE(cmd), GFP_KERNEL);
- if (NULL == mbuf)
- return -ENOMEM;
- parg = mbuf;
- }
-
- err = -EFAULT;
- if (_IOC_DIR(cmd) & _IOC_WRITE) {
- unsigned long n = cmd_input_size(cmd);
-
- if (copy_from_user(parg, (void __user *)arg, n))
- goto out;
-
- /* zero out anything we don't copy from userspace */
- if (n < _IOC_SIZE(cmd))
- memset((u8 *)parg + n, 0, _IOC_SIZE(cmd) - n);
- } else {
- /* read-only ioctl */
- memset(parg, 0, _IOC_SIZE(cmd));
- }
- }
-
- if (is_ext_ctrl) {
- struct v4l2_ext_controls *p = parg;
-
- /* In case of an error, tell the caller that it wasn't
- a specific control that caused it. */
- p->error_idx = p->count;
- user_ptr = (void __user *)p->controls;
- if (p->count) {
- ctrls_size = sizeof(struct v4l2_ext_control) * p->count;
- /* Note: v4l2_ext_controls fits in sbuf[] so mbuf is still NULL. */
- mbuf = kmalloc(ctrls_size, GFP_KERNEL);
- err = -ENOMEM;
- if (NULL == mbuf)
- goto out_ext_ctrl;
- err = -EFAULT;
- if (copy_from_user(mbuf, user_ptr, ctrls_size))
- goto out_ext_ctrl;
- p->controls = mbuf;
- }
- }
-
- /* Handles IOCTL */
- err = __video_do_ioctl(file, cmd, parg);
- if (err == -ENOIOCTLCMD)
- err = -EINVAL;
- if (is_ext_ctrl) {
- struct v4l2_ext_controls *p = parg;
-
- p->controls = (void *)user_ptr;
- if (p->count && err == 0 && copy_to_user(user_ptr, mbuf, ctrls_size))
- err = -EFAULT;
- goto out_ext_ctrl;
- }
- if (err < 0)
- goto out;
-
-out_ext_ctrl:
- /* 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(cmd)))
- err = -EFAULT;
- break;
- }
-
-out:
- kfree(mbuf);
- return err;
+ return __video_usercopy(file, cmd, arg, __video_do_ioctl);
}
EXPORT_SYMBOL(video_ioctl2);
--
1.7.2.2
--
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