linux-kernel - [PATCH] drm/kmb: Fix an error handling path

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 19 May 2021 22:47:02 +0200
From:   Christophe JAILLET <christophe.jaillet@...adoo.fr>
To:     anitha.chrisanthus@...el.com, edmund.j.dea@...el.com,
        airlied@...ux.ie, daniel@...ll.ch, sam@...nborg.org
Cc:     dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        kernel-janitors@...r.kernel.org,
        Christophe JAILLET <christophe.jaillet@...adoo.fr>
Subject: [PATCH] drm/kmb: Fix an error handling path

If 'platform_get_irq()' fails, it is spurious to call
'of_reserved_mem_device_release()' in the error handling path, because
'of_reserved_mem_device_init() has not been called yet.

Moreover, a previous 'kmb_initialize_clocks()' is unbalanced by a
corresponding 'kmb_display_clk_disable()' call, has already done in the
remove function.

It is likely that 'kmb_display_clk_disable()' is expected in the error
handling path, instead of 'kmb_display_clk_disable()'.


Also, it is spurious to return directly if 'of_reserved_mem_device_init()'
fails.
Goto the error handling path instead to free some resources.

Fixes: 7f7b96a8a0a1 ("drm/kmb: Add support for KeemBay Display")
Signed-off-by: Christophe JAILLET <christophe.jaillet@...adoo.fr>
---
 drivers/gpu/drm/kmb/kmb_drv.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/kmb/kmb_drv.c b/drivers/gpu/drm/kmb/kmb_drv.c
index f64e06e1067d..b41b8789fe57 100644
--- a/drivers/gpu/drm/kmb/kmb_drv.c
+++ b/drivers/gpu/drm/kmb/kmb_drv.c
@@ -138,13 +138,13 @@ static int kmb_hw_init(struct drm_device *drm, unsigned long flags)
 	irq_lcd = platform_get_irq(pdev, 0);
 	if (irq_lcd < 0) {
 		drm_err(&kmb->drm, "irq_lcd not found");
-		goto setup_fail;
+		goto disable_clk_err;
 	}
 
 	/* Get the optional framebuffer memory resource */
 	ret = of_reserved_mem_device_init(drm->dev);
 	if (ret && ret != -ENODEV)
-		return ret;
+		goto disable_clk_err;
 
 	spin_lock_init(&kmb->irq_lock);
 
@@ -152,8 +152,8 @@ static int kmb_hw_init(struct drm_device *drm, unsigned long flags)
 
 	return 0;
 
- setup_fail:
-	of_reserved_mem_device_release(drm->dev);
+ disable_clk_err:
+	kmb_display_clk_disable(kmb);
 
 	return ret;
 }
-- 
2.30.2