[PATCH v3 0/3] scsi:iscsi: handle iscsi_cls_conn device with sysfs correctly

Wenchao Hao
2022-03-09T12:48:00Z

We found a NULL pointer dereference in iscsi_sw_tcp_conn_get_param(),
the root reason is we did sysfs addition wrong.

The origin implement do device setup in iscsi_create_conn() which
bind the alloc/init and add in one function; do device teardown in
iscsi_destroy_conn() which bind remove and free in one function.

This implement makes it impossible to initialize resources of device
before add it to sysfs during setup.

So this patchset splict both the setup and teradown of iscsi_cls_conn to
2 steps.

For setup flow, we should call iscsi_alloc_conn() and initialize some
resources, then call iscsi_add_conn().

For teradown flow, we should call iscsi_remove_conn() to remove device
and free resources which related to iscsi_cls_conn, then call
iscsi_put_conn() to free iscsi_cls_conn.

V2 -> V3:
* Fix some bugs and optimization the code implement.

V1 -> V2:
* add two more iscsi_free_conn() and iscsi_remove_conn() than V1
* change the teardown flow of iscsi_cls_conn

Wenchao Hao (3):
scsi: iscsi: Add helper functions to manage iscsi_cls_conn
scsi:libiscsi: Add iscsi_cls_conn to sysfs after been initialized
scsi:libiscsi: teradown iscsi_cls_conn gracefully

drivers/scsi/libiscsi.c | 23 +++++---
drivers/scsi/scsi_transport_iscsi.c | 90 +++++++++++++++--------------
include/scsi/scsi_transport_iscsi.h | 5 +-
3 files changed, 66 insertions(+), 52 deletions(-)

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2.32.0