drm/msm: fix leak in failed get_pages

get_pages doesn't keep a reference of the pages allocated
when it fails later in the code path. This can lead to
a memory leak. Keep reference of the allocated pages so
that it can be freed when msm_gem_free_object gets called
later during cleanup.

Change-Id: I44dea20e10c056c1c5e80d01bab0a274ff768b1c
Signed-off-by: Prakash Kamliya <pkamliya@codeaurora.org>

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 4bee797..8f2a0ee 100644 (file)
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -113,13 +113,15 @@ static struct page **get_pages(struct drm_gem_object *obj)
                        return p;
                }
 
+               msm_obj->pages = p;
+
                msm_obj->sgt = drm_prime_pages_to_sg(p, npages);
                if (IS_ERR(msm_obj->sgt)) {
-                       dev_err(dev->dev, "failed to allocate sgt\n");
-                       return ERR_CAST(msm_obj->sgt);
-               }
+                       void *ptr = ERR_CAST(msm_obj->sgt);
 
-               msm_obj->pages = p;
+                       msm_obj->sgt = NULL;
+                       return ptr;
+               }
 
                /*
                 * Make sure to flush the CPU cache for newly allocated memory
@@ -157,7 +159,8 @@ static void put_pages(struct drm_gem_object *obj)
                        msm_obj->flags &= ~MSM_BO_LOCKED;
                }
 
-               sg_free_table(msm_obj->sgt);
+               if (msm_obj->sgt)
+                       sg_free_table(msm_obj->sgt);
                kfree(msm_obj->sgt);
 
                if (use_pages(obj)) {