[PATCH 1/4] drm/msm: fix memleak on release

Johan Hovold
2019-10-10T13:14:38Z

If a process is interrupted while accessing the "gpu" debugfs file and
the drm device struct_mutex is contended, release() could return early
and fail to free related resources.

Note that the return value from release() is ignored.

Fixes: 4f776f4511c7 ("drm/msm/gpu: Convert the GPU show function to use the GPU state")
Cc: stable <stable@vger.kernel.org> # 4.18
Cc: Jordan Crouse <jcrouse@codeaurora.org>
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
drivers/gpu/drm/msm/msm_debugfs.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_debugfs.c b/drivers/gpu/drm/msm/msm_debugfs.c
index 6be879578140..1c74381a4fc9 100644
--- a/drivers/gpu/drm/msm/msm_debugfs.c
+++ b/drivers/gpu/drm/msm/msm_debugfs.c
@@ -47,12 +47,8 @@ static int msm_gpu_release(struct inode *inode, struct file *file)
struct msm_gpu_show_priv *show_priv = m->private;
struct msm_drm_private *priv = show_priv->dev->dev_private;
struct msm_gpu *gpu = priv->gpu;
- int ret;
-
- ret = mutex_lock_interruptible(&show_priv->dev->struct_mutex);
- if (ret)
- return ret;

+ mutex_lock(&show_priv->dev->struct_mutex);
gpu->funcs->gpu_state_put(show_priv->state);
mutex_unlock(&show_priv->dev->struct_mutex);

--
2.23.0