Patch "drm/fb-helper: Add missed unlocks in setcmap_legacy()" has been added to the 5.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    drm/fb-helper: Add missed unlocks in setcmap_legacy()

to the 5.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-fb-helper-add-missed-unlocks-in-setcmap_legacy.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 04bc9b06f963609161ce6bf5c21200289425ea24
Author: Chuhong Yuan <hslester96@xxxxxxxxx>
Date:   Thu Dec 3 22:42:48 2020 +0800

    drm/fb-helper: Add missed unlocks in setcmap_legacy()
    
    [ Upstream commit 0a260e731d6c4c17547ac275a2cde888a9eb4a3d ]
    
    setcmap_legacy() does not call drm_modeset_unlock_all() in some exits,
    add the missed unlocks with goto to fix it.
    
    Fixes: 964c60063bff ("drm/fb-helper: separate the fb_setcmap helper into atomic and legacy paths")
    Signed-off-by: Chuhong Yuan <hslester96@xxxxxxxxx>
    Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
    Link: https://patchwork.freedesktop.org/patch/msgid/20201203144248.418281-1-hslester96@xxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 6b8502bcf0fd3..02ffde5fd7226 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -965,11 +965,15 @@ static int setcmap_legacy(struct fb_cmap *cmap, struct fb_info *info)
 	drm_modeset_lock_all(fb_helper->dev);
 	drm_client_for_each_modeset(modeset, &fb_helper->client) {
 		crtc = modeset->crtc;
-		if (!crtc->funcs->gamma_set || !crtc->gamma_size)
-			return -EINVAL;
+		if (!crtc->funcs->gamma_set || !crtc->gamma_size) {
+			ret = -EINVAL;
+			goto out;
+		}
 
-		if (cmap->start + cmap->len > crtc->gamma_size)
-			return -EINVAL;
+		if (cmap->start + cmap->len > crtc->gamma_size) {
+			ret = -EINVAL;
+			goto out;
+		}
 
 		r = crtc->gamma_store;
 		g = r + crtc->gamma_size;
@@ -982,8 +986,9 @@ static int setcmap_legacy(struct fb_cmap *cmap, struct fb_info *info)
 		ret = crtc->funcs->gamma_set(crtc, r, g, b,
 					     crtc->gamma_size, NULL);
 		if (ret)
-			return ret;
+			goto out;
 	}
+out:
 	drm_modeset_unlock_all(fb_helper->dev);
 
 	return ret;