[PATCH] drm: Reject getfb for multi-plane framebuffers

[Daniel Stone]

getfb can only return a single plane, so reject attempts to use it with
multi-plane framebuffers.

Signed-off-by: Daniel Stone <daniels at collabora.com>
Reported-by: Daniel van Vugt <daniel.van.vugt at canonical.com>
Fixes: 308e5bcbdb10 ("drm: add an fb creation ioctl that takes a pixel format v5")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105518
---
 drivers/gpu/drm/drm_framebuffer.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
index 7df025669067..ad67203de715 100644
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -462,6 +462,12 @@ int drm_mode_getfb(struct drm_device *dev,
 	if (!fb)
 		return -ENOENT;
 
+	/* Multi-planar framebuffers need getfb2. */
+	if (fb->format->num_planes > 1) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	r->height = fb->height;
 	r->width = fb->width;
 	r->depth = fb->format->depth;
@@ -485,6 +491,7 @@ int drm_mode_getfb(struct drm_device *dev,
 		ret = -ENODEV;
 	}
 
+out:
 	drm_framebuffer_put(fb);
 
 	return ret;
-- 
2.16.2