From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leon Romanovsky Subject: [PATCH rdma-next 3/3] IB/core: Fix sysfs registration error flow Date: Sun, 19 Mar 2017 10:55:57 +0200 Message-ID: <20170319085557.6023-4-leon@kernel.org> References: <20170319085557.6023-1-leon@kernel.org> Return-path: In-Reply-To: <20170319085557.6023-1-leon@kernel.org> Sender: stable-owner@vger.kernel.org To: Doug Ledford Cc: linux-rdma@vger.kernel.org, Jack Morgenstein , "# v4 . 2+" List-Id: linux-rdma@vger.kernel.org From: Jack Morgenstein The kernel commit cited below restructured ib device management so that the device kobject is initialized in ib_alloc_device. As part of the restructuring, the kobject is now initialized in procedure ib_alloc_device, and is later added to the device hierarchy in the ib_register_device call stack, in procedure ib_device_register_sysfs (which calls device_add). However, in the ib_device_register_sysfs error flow, if an error occurs following the call to device_add, the cleanup procedure device_unregister is called. This call results in the device object being deleted -- which results in various use-after-free crashes. The correct cleanup call is device_del -- which undoes device_add without deleting the device object. The device object will then (correctly) be deleted in the ib_register_device caller's error cleanup flow, when the caller invokes ib_dealloc_device. Fixes: 55aeed06544f6 ("IB/core: Make ib_alloc_device init the kobject") Cc: # v4.2+ Signed-off-by: Jack Morgenstein Signed-off-by: Leon Romanovsky --- drivers/infiniband/core/sysfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/infiniband/core/sysfs.c b/drivers/infiniband/core/sysfs.c index daadf3130c9f..48bb75503255 100644 --- a/drivers/infiniband/core/sysfs.c +++ b/drivers/infiniband/core/sysfs.c @@ -1301,7 +1301,7 @@ int ib_device_register_sysfs(struct ib_device *device, free_port_list_attributes(device); err_unregister: - device_unregister(class_dev); + device_del(class_dev); err: return ret; -- 2.12.0