[PATCH 5.4 148/168] RDMA/siw: Fix failure handling during device creation

Greg Kroah-Hartman
2020-03-10T12:55:49Z

From: Bernard Metzler <bmt@zurich.ibm.com>

commit 12e5eef0f4d8087ea7b559f6630be08ffea2d851 upstream.

A failing call to ib_device_set_netdev() during device creation caused
system crash due to xa_destroy of uninitialized xarray hit by device
deallocation. Fixed by moving xarray initialization before potential
device deallocation.

Fixes: bdcf26bf9b3a ("rdma/siw: network and RDMA core interface")
Link: https://lore.kernel.org/r/20200302155814.9896-1-bmt@zurich.ibm.com
Reported-by: syzbot+2e80962bedd9559fe0b3@syzkaller.appspotmail.com
Signed-off-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/infiniband/sw/siw/siw_main.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/infiniband/sw/siw/siw_main.c
+++ b/drivers/infiniband/sw/siw/siw_main.c
@@ -379,6 +379,9 @@ static struct siw_device *siw_device_cre
base_dev->dev.dma_ops = &dma_virt_ops;
base_dev->num_comp_vectors = num_possible_cpus();

+ xa_init_flags(&sdev->qp_xa, XA_FLAGS_ALLOC1);
+ xa_init_flags(&sdev->mem_xa, XA_FLAGS_ALLOC1);
+
ib_set_device_ops(base_dev, &siw_device_ops);
rv = ib_device_set_netdev(base_dev, netdev, 1);
if (rv)
@@ -406,9 +409,6 @@ static struct siw_device *siw_device_cre
sdev->attrs.max_srq_wr = SIW_MAX_SRQ_WR;
sdev->attrs.max_srq_sge = SIW_MAX_SGE;

- xa_init_flags(&sdev->qp_xa, XA_FLAGS_ALLOC1);
- xa_init_flags(&sdev->mem_xa, XA_FLAGS_ALLOC1);
-
INIT_LIST_HEAD(&sdev->cep_list);
INIT_LIST_HEAD(&sdev->qp_list);