From b312be3d87e4c80872cbea869e569175c5eb0f9a Mon Sep 17 00:00:00 2001 From: Jack Morgenstein Date: Sun, 19 Mar 2017 10:55:57 +0200 Subject: [PATCH] IB/core: Fix sysfs registration error flow 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 Signed-off-by: Doug Ledford --- 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 @@ err_put: free_port_list_attributes(device); err_unregister: - device_unregister(class_dev); + device_del(class_dev); err: return ret;