[PATCH] fio: make sure io_u->file isn't NULL before using it

[Luís Henriques <lhenriques@xxxxxxx>]

While running fstests generic/095 against ext4 on a zram device I started
seeing fio crashing.  Fix it by making sure io_u->file isn't NULL before
accessing it.

Signed-off-by: Luís Henriques <lhenriques@xxxxxxx>
---
 io_u.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/io_u.c b/io_u.c
index 5289b5d1d9c6..b8e715d4118c 100644
--- a/io_u.c
+++ b/io_u.c
@@ -2009,7 +2009,8 @@ static void io_completed(struct thread_data *td, struct io_u **io_u_ptr,
 			io_u->xfer_buf += bytes;
 			io_u->offset += bytes;
 			td->ts.short_io_u[io_u->ddir]++;
-			if (io_u->offset < io_u->file->real_file_size) {
+			if (io_u->file &&
+			    (io_u->offset < io_u->file->real_file_size)) {
 				requeue_io_u(td, io_u_ptr);
 				return;
 			}