[PATCH 5.13 174/300] drm/msm/dsi: Fix some reference counted resource leaks

Greg Kroah-Hartman
2021-09-13T14:07:54Z

From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

[ Upstream commit 6977cc89c87506ff17e6c05f0e37f46752256e82 ]

'of_find_device_by_node()' takes a reference that must be released when
not needed anymore.
This is expected to be done in 'dsi_destroy()'.

However, there are 2 issues in 'dsi_get_phy()'.

First, if 'of_find_device_by_node()' succeeds but 'platform_get_drvdata()'
returns NULL, 'msm_dsi->phy_dev' will still be NULL, and the reference
won't be released in 'dsi_destroy()'.

Secondly, as 'of_find_device_by_node()' already takes a reference, there is
no need for an additional 'get_device()'.

Move the assignment to 'msm_dsi->phy_dev' a few lines above and remove the
unneeded 'get_device()' to solve both issues.

Fixes: ec31abf6684e ("drm/msm/dsi: Separate PHY to another platform device")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/f15bc57648a00e7c99f943903468a04639d50596.1628241097.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/msm/dsi/dsi.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/msm/dsi/dsi.c b/drivers/gpu/drm/msm/dsi/dsi.c
index 627048851d99..7e364b9c9f9e 100644
--- a/drivers/gpu/drm/msm/dsi/dsi.c
+++ b/drivers/gpu/drm/msm/dsi/dsi.c
@@ -26,8 +26,10 @@ static int dsi_get_phy(struct msm_dsi *msm_dsi)
}

phy_pdev = of_find_device_by_node(phy_node);
- if (phy_pdev)
+ if (phy_pdev) {
msm_dsi->phy = platform_get_drvdata(phy_pdev);
+ msm_dsi->phy_dev = &phy_pdev->dev;
+ }

of_node_put(phy_node);

@@ -36,8 +38,6 @@ static int dsi_get_phy(struct msm_dsi *msm_dsi)
return -EPROBE_DEFER;
}

- msm_dsi->phy_dev = get_device(&phy_pdev->dev);
-
return 0;
}

--
2.30.2