1 From e521813468f786271a87e78e8644243bead48fad Mon Sep 17 00:00:00 2001
2 From: Julian Wiedmann <jwi@linux.ibm.com>
3 Date: Wed, 2 May 2018 08:48:43 +0200
4 Subject: s390/qdio: fix access to uninitialized qdio_q fields
6 From: Julian Wiedmann <jwi@linux.ibm.com>
8 commit e521813468f786271a87e78e8644243bead48fad upstream.
10 Ever since CQ/QAOB support was added, calling qdio_free() straight after
11 qdio_alloc() results in qdio_release_memory() accessing uninitialized
12 memory (ie. q->u.out.use_cq and q->u.out.aobs). Followed by a
13 kmem_cache_free() on the random AOB addresses.
15 For older kernels that don't have 6e30c549f6ca, the same applies if
16 qdio_establish() fails in the DEV_STATE_ONLINE check.
18 While initializing q->u.out.use_cq would be enough to fix this
19 particular bug, the more future-proof change is to just zero-alloc the
22 Fixes: 104ea556ee7f ("qdio: support asynchronous delivery of storage blocks")
23 Cc: <stable@vger.kernel.org> #v3.2+
24 Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
25 Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
26 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
29 drivers/s390/cio/qdio_setup.c | 2 +-
30 1 file changed, 1 insertion(+), 1 deletion(-)
32 --- a/drivers/s390/cio/qdio_setup.c
33 +++ b/drivers/s390/cio/qdio_setup.c
34 @@ -140,7 +140,7 @@ static int __qdio_allocate_qs(struct qdi
37 for (i = 0; i < nr_queues; i++) {
38 - q = kmem_cache_alloc(qdio_q_cache, GFP_KERNEL);
39 + q = kmem_cache_zalloc(qdio_q_cache, GFP_KERNEL);