Revert "mm: mmap: fix fput in error path v2"

The kernel test robot is not happy with that.

This reverts commit 0227da01.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NDaniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/394772/

drivers/dma-buf/dma-buf.c

@@ -1166,6 +1166,9 @@ EXPORT_SYMBOL_GPL(dma_buf_end_cpu_access);
 int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
 		 unsigned long pgoff)
 {
+	struct file *oldfile;
+	int ret;
+
 	if (WARN_ON(!dmabuf || !vma))
 		return -EINVAL;
 
@@ -1183,11 +1186,22 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
 		return -EINVAL;
 
 	/* readjust the vma */
-	fput(vma->vm_file);
-	vma->vm_file = get_file(dmabuf->file);
+	get_file(dmabuf->file);
+	oldfile = vma->vm_file;
+	vma->vm_file = dmabuf->file;
 	vma->vm_pgoff = pgoff;
 
-	return dmabuf->ops->mmap(dmabuf, vma);
+	ret = dmabuf->ops->mmap(dmabuf, vma);
+	if (ret) {
+		/* restore old parameters on failure */
+		vma->vm_file = oldfile;
+		fput(dmabuf->file);
+	} else {
+		if (oldfile)
+			fput(oldfile);
+	}
+	return ret;
+
 }
 EXPORT_SYMBOL_GPL(dma_buf_mmap);
 

mm/mmap.c

@@ -1899,8 +1899,8 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
 	return addr;
 
 unmap_and_free_vma:
-	fput(vma->vm_file);
 	vma->vm_file = NULL;
+	fput(file);
 
 	/* Undo any partial mapping done by a device driver. */
 	unmap_region(mm, vma, prev, vma->vm_start, vma->vm_end);