file: ensure cleanup

Brown paper bag time. This is a silly oversight where I missed to drop
the error condition checking to ensure we clean up on early error
returns. I have an internal unit testset coming up for this which will
catch all such issues going forward.

Reported-by: Chris Mason <[e-mail]>
Reported-by: Jeff Layton <[e-mail]>
Fixes: 011703a9acd7 ("file: add FD_{ADD,PREPARE}()")
Signed-off-by: Christian Brauner <[e-mail]>
Reviewed-by: Jeff Layton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/linux/file.h

···
 /* Do not use directly. */
 static inline void class_fd_prepare_destructor(const struct fd_prepare *fdf)
 {
-	if (unlikely(fdf->err)) {
-		if (likely(fdf->__fd >= 0))
-			put_unused_fd(fdf->__fd);
-		if (unlikely(!IS_ERR_OR_NULL(fdf->__file)))
-			fput(fdf->__file);
-	}
+	if (unlikely(fdf->__fd >= 0))
+		put_unused_fd(fdf->__fd);
+	if (unlikely(!IS_ERR_OR_NULL(fdf->__file)))
+		fput(fdf->__file);
 }
 
 /* Do not use directly. */
···
 		VFS_WARN_ON_ONCE(fdp->__fd < 0);               \
 		VFS_WARN_ON_ONCE(IS_ERR_OR_NULL(fdp->__file)); \
 		fd_install(fdp->__fd, fdp->__file);            \
-		fdp->__fd;                                     \
+		retain_and_null_ptr(fdp->__file);              \
+		take_fd(fdp->__fd);                            \
 	})
 
 /* Do not use directly. */