gpu: nvgpu: fix crash in gk20a_channel_release

gk20a_channel_release() should bail if filp->private_data is
NULL. This can happen as a result of gk20a_channel_release()
being called when __gk20a_channel_open() fails in
NVHOST_IOCTL_CHANNEL_OPEN.

Bug 200014898

Change-Id: I32cc957aca46fcd4265a8052ac5be355b644b9f7
Signed-off-by: Aingara Paramakuru <aparamakuru@nvidia.com>
Reviewed-on: http://git-master/r/496138
Reviewed-by: Ken Adams <kadams@nvidia.com>
Tested-by: Ken Adams <kadams@nvidia.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
index 669ec294..c174afcd 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
@@ -708,9 +708,12 @@ unbind:
 int gk20a_channel_release(struct inode *inode, struct file *filp)
 {
         struct channel_gk20a *ch = (struct channel_gk20a *)filp->private_data;
-        struct gk20a *g = ch->g;
+        struct gk20a *g = ch ? ch->g : NULL;
         int err;
 
+        if (!ch)
+                return 0;
+
         trace_gk20a_channel_release(dev_name(&g->dev->dev));
 
         err = gk20a_busy(ch->g->dev);