558d52b297
The rnbd_server module's communication manager (cm) initialization depends
on the registration of the "network namespace subsystem" of the RDMA CM
agent module. As such, when the kernel is configured to load the
rnbd_server and the RDMA cma module during initialization; and if the
rnbd_server module is initialized before RDMA cma module, a null ptr
dereference occurs during the RDMA bind operation.
Call trace:
Call Trace:
? xas_load+0xd/0x80
xa_load+0x47/0x80
cma_ps_find+0x44/0x70
rdma_bind_addr+0x782/0x8b0
? get_random_bytes+0x35/0x40
rtrs_srv_cm_init+0x50/0x80
rtrs_srv_open+0x102/0x180
? rnbd_client_init+0x6e/0x6e
rnbd_srv_init_module+0x34/0x84
? rnbd_client_init+0x6e/0x6e
do_one_initcall+0x4a/0x200
kernel_init_freeable+0x1f1/0x26e
? rest_init+0xb0/0xb0
kernel_init+0xe/0x100
ret_from_fork+0x22/0x30
Modules linked in:
CR2: 0000000000000015
All this happens cause the cm init is in the call chain of the module
init, which is not a preferred practice.
So remove the call to rdma_create_id() from the module init call chain.
Instead register rtrs-srv as an ib client, which makes sure that the
rdma_create_id() is called only when an ib device is added.
Fixes: 9cb837480424 ("RDMA/rtrs: server: main functionality")
Link: https://lore.kernel.org/r/20200907103106.104530-1-haris.iqbal@cloud.ionos.com
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.