git: 55d183367104 - main - ibcore: Fix sysfs registration error flow

From: Hans Petter Selasky <hselasky_at_FreeBSD.org>
Date: Tue, 21 Jun 2022 09:34:07 UTC
The branch main has been updated by hselasky:

URL: https://cgit.FreeBSD.org/src/commit/?id=55d183367104e3efcdaa936f65e4f82303871271

commit 55d183367104e3efcdaa936f65e4f82303871271
Author:     Hans Petter Selasky <hselasky@FreeBSD.org>
AuthorDate: 2022-06-21 09:07:06 +0000
Commit:     Hans Petter Selasky <hselasky@FreeBSD.org>
CommitDate: 2022-06-21 09:33:27 +0000

    ibcore: 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.
    
    Linux commit:
    b312be3d87e4c80872cbea869e569175c5eb0f9a
    
    PR:             264472
    MFC after:      3 days
    Sponsored by:   NVIDIA Networking
---
 sys/ofed/drivers/infiniband/core/ib_sysfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/ofed/drivers/infiniband/core/ib_sysfs.c b/sys/ofed/drivers/infiniband/core/ib_sysfs.c
index 4cbb69ad899b..63f6c2641b83 100644
--- a/sys/ofed/drivers/infiniband/core/ib_sysfs.c
+++ b/sys/ofed/drivers/infiniband/core/ib_sysfs.c
@@ -1366,7 +1366,7 @@ err_put:
 	free_port_list_attributes(device);
 
 err_unregister:
-	device_unregister(class_dev);
+	device_del(class_dev);
 
 err:
 	return ret;