UBUNTU: SAUCE: coverity: fix null pointer dereference

(backported from /pull/438 commit
8245707)
Signed-off-by: You-Sheng Yang <vicamo@gmail.com>

Gbp-Pq: Name 0015-coverity-fix-null-pointer-dereference.patch

v4l2loopback.c

@@ -525,6 +525,9 @@ static ssize_t attr_store_format(struct device *cd,
 	struct v4l2_loopback_device *dev = v4l2loopback_cd2dev(cd);
 	int fps_num = 0, fps_den = 1;
 
+	if (!dev)
+		return -ENODEV;
+
 	/* only fps changing is supported */
 	if (sscanf(buf, "@%d/%d", &fps_num, &fps_den) > 0) {
 		struct v4l2_fract f = { .numerator = fps_den,
@@ -545,6 +548,9 @@ static ssize_t attr_show_buffers(struct device *cd,
 {
 	struct v4l2_loopback_device *dev = v4l2loopback_cd2dev(cd);
 
+	if (!dev)
+		return -ENODEV;
+
 	return sprintf(buf, "%d\n", dev->used_buffers);
 }
 
@@ -555,6 +561,9 @@ static ssize_t attr_show_maxopeners(struct device *cd,
 {
 	struct v4l2_loopback_device *dev = v4l2loopback_cd2dev(cd);
 
+	if (!dev)
+		return -ENODEV;
+
 	return sprintf(buf, "%d\n", dev->max_openers);
 }
 
@@ -569,6 +578,8 @@ static ssize_t attr_store_maxopeners(struct device *cd,
 		return -EINVAL;
 
 	dev = v4l2loopback_cd2dev(cd);
+	if (!dev)
+		return -ENODEV;
 
 	if (dev->max_openers == curr)
 		return len;
@@ -1209,7 +1220,7 @@ static int vidioc_queryctrl(struct file *file, void *fh,
 	if (!cnf)
 		BUG();
 
-	strcpy(q->name, cnf->name);
+	strlcpy(q->name, cnf->name, sizeof(q->name));
 	q->default_value = cnf->def;
 	q->type = cnf->type;
 	q->minimum = cnf->min;