[PATCH] tee/tee_shm.c: Fix error handling path

[Souptick Joarder]

When shm->num_pages <= 0, we should avoid calling
release_registered_pages() in error handling path.

Signed-off-by: Souptick Joarder <jrdr.li...@gmail.com>
Cc: John Hubbard <jhubb...@nvidia.com>
---
 drivers/tee/tee_shm.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
index 00472f5..e517d9f 100644
--- a/drivers/tee/tee_shm.c
+++ b/drivers/tee/tee_shm.c
@@ -260,8 +260,7 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, 
unsigned long addr,
                rc = get_kernel_pages(kiov, num_pages, 0, shm->pages);
                kfree(kiov);
        }
-       if (rc > 0)
-               shm->num_pages = rc;
+       shm->num_pages = rc;
        if (rc != num_pages) {
                if (rc >= 0)
                        rc = -ENOMEM;
@@ -309,7 +308,9 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, 
unsigned long addr,
                        idr_remove(&teedev->idr, shm->id);
                        mutex_unlock(&teedev->mutex);
                }
-               release_registered_pages(shm);
+               if (shm->pages && (shm->num_pages > 0))
+                       release_registered_pages(shm);
+
        }
        kfree(shm);
        teedev_ctx_put(ctx);
-- 
1.9.1