drm/nouveau: move dereferences after null checks

Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Maarten Maathuis <madman2003@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

4 files changed, 17 insertions, 11 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 7e6d673f3a23..d2f63353ea97 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -88,13 +88,14 @@ nouveau_connector_destroy(struct drm_connector *drm_connector)
 {
         struct nouveau_connector *nv_connector =
                 nouveau_connector(drm_connector);
-        struct drm_device *dev = nv_connector->base.dev;
-
-        NV_DEBUG_KMS(dev, "\n");
+        struct drm_device *dev;
 
         if (!nv_connector)
                 return;
 
+        dev = nv_connector->base.dev;
+        NV_DEBUG_KMS(dev, "\n");
+
         kfree(nv_connector->edid);
         drm_sysfs_connector_remove(drm_connector);
         drm_connector_cleanup(drm_connector);
diff --git a/drivers/gpu/drm/nouveau/nouveau_object.c b/drivers/gpu/drm/nouveau/nouveau_object.c
index 6c2cf81716df..e7c100ba63a1 100644
--- a/drivers/gpu/drm/nouveau/nouveau_object.c
+++ b/drivers/gpu/drm/nouveau/nouveau_object.c
@@ -885,11 +885,12 @@ int
 nouveau_gpuobj_sw_new(struct nouveau_channel *chan, int class,
                       struct nouveau_gpuobj **gpuobj_ret)
 {
-        struct drm_nouveau_private *dev_priv = chan->dev->dev_private;
+        struct drm_nouveau_private *dev_priv;
         struct nouveau_gpuobj *gpuobj;
 
         if (!chan || !gpuobj_ret || *gpuobj_ret != NULL)
                 return -EINVAL;
+        dev_priv = chan->dev->dev_private;
 
         gpuobj = kzalloc(sizeof(*gpuobj), GFP_KERNEL);
         if (!gpuobj)
diff --git a/drivers/gpu/drm/nouveau/nouveau_sgdma.c b/drivers/gpu/drm/nouveau/nouveau_sgdma.c
index 4c7f1e403e80..ed1590577b6c 100644
--- a/drivers/gpu/drm/nouveau/nouveau_sgdma.c
+++ b/drivers/gpu/drm/nouveau/nouveau_sgdma.c
@@ -54,11 +54,12 @@ static void
 nouveau_sgdma_clear(struct ttm_backend *be)
 {
         struct nouveau_sgdma_be *nvbe = (struct nouveau_sgdma_be *)be;
-        struct drm_device *dev = nvbe->dev;
-
-        NV_DEBUG(nvbe->dev, "\n");
+        struct drm_device *dev;
 
         if (nvbe && nvbe->pages) {
+                dev = nvbe->dev;
+                NV_DEBUG(dev, "\n");
+
                 if (nvbe->bound)
                         be->func->unbind(be);
 
diff --git a/drivers/gpu/drm/nouveau/nv50_crtc.c b/drivers/gpu/drm/nouveau/nv50_crtc.c
index 40b7360841f8..d1a651e3400c 100644
--- a/drivers/gpu/drm/nouveau/nv50_crtc.c
+++ b/drivers/gpu/drm/nouveau/nv50_crtc.c
@@ -298,14 +298,17 @@ nv50_crtc_set_clock(struct drm_device *dev, int head, int pclk)
 static void
 nv50_crtc_destroy(struct drm_crtc *crtc)
 {
-        struct drm_device *dev = crtc->dev;
-        struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
-
-        NV_DEBUG_KMS(dev, "\n");
+        struct drm_device *dev;
+        struct nouveau_crtc *nv_crtc;
 
         if (!crtc)
                 return;
 
+        dev = crtc->dev;
+        nv_crtc = nouveau_crtc(crtc);
+
+        NV_DEBUG_KMS(dev, "\n");
+
         drm_crtc_cleanup(&nv_crtc->base);
 
         nv50_cursor_fini(nv_crtc);