On 9/25/2018 9:51 AM, Leon Romanovsky wrote:
> On Tue, Sep 25, 2018 at 07:15:14PM +0300, Mark Bloch wrote:
>>
>>
>> On 9/25/2018 5:10 AM, Leon Romanovsky wrote:
>>> From: Leon Romanovsky <leonro@xxxxxxxxxxxx>
>>>
>>> Provide an option to rename IB device name through RDMA netlink and
>>> limit it to users with ADMIN capability only.
>>>
>>> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
>>> ---
>>> drivers/infiniband/core/nldev.c | 33 +++++++++++++++++++++++++++++++++
>>> include/uapi/rdma/rdma_netlink.h | 3 ++-
>>> 2 files changed, 35 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c
>>> index ba5403fbcd88..e841725a0ee0 100644
>>> --- a/drivers/infiniband/core/nldev.c
>>> +++ b/drivers/infiniband/core/nldev.c
>>> @@ -646,6 +646,35 @@ static int nldev_get_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
>>> return err;
>>> }
>>>
>>> +static int nldev_set_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
>>> + struct netlink_ext_ack *extack)
>>> +{
>>> + struct nlattr *tb[RDMA_NLDEV_ATTR_MAX];
>>> + struct ib_device *device;
>>> + u32 index;
>>> + int err;
>>> +
>>> + err = nlmsg_parse(nlh, 0, tb, RDMA_NLDEV_ATTR_MAX - 1, nldev_policy,
>>> + extack);
>>> + if (err || !tb[RDMA_NLDEV_ATTR_DEV_INDEX])
>>> + return -EINVAL;
>>> +
>>> + index = nla_get_u32(tb[RDMA_NLDEV_ATTR_DEV_INDEX]);
>>> + device = ib_device_get_by_index(index);
>>> + if (!device)
>>> + return -EINVAL;
>>> +
>>> + if (tb[RDMA_NLDEV_ATTR_DEV_NAME]) {
>>> + char name[IB_DEVICE_NAME_MAX] = {};
>>> +
>>> + nla_strlcpy(name, tb[RDMA_NLDEV_ATTR_DEV_NAME],
>>> + IB_DEVICE_NAME_MAX);
>>
>> I wonder if we want to check the length here, as we need it to be
>> IB_DEVICE_NAME_MAX - 1 + \0, nla_strlcpy will copy at most IB_DEVICE_NAME_MAX - 1
>> which might be less than what the user passed.
>
> It is supposed to be covered by nla_policy, RDMA_NLDEV_ATTR_DEV_NAME is
> declared as NLA_NUL_STRING, so I think it is ok do not check size again.
>
> Thanks
Right, brain fart! sorry for the noise :)
Mark
>
>>
>>> + return ib_device_rename(device, name);
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> static int _nldev_get_dumpit(struct ib_device *device,
>>> struct sk_buff *skb,
>>> struct netlink_callback *cb,
>>> @@ -1078,6 +1107,10 @@ static const struct rdma_nl_cbs nldev_cb_table[RDMA_NLDEV_NUM_OPS] = {
>>> .doit = nldev_get_doit,
>>> .dump = nldev_get_dumpit,
>>> },
>>> + [RDMA_NLDEV_CMD_SET] = {
>>> + .doit = nldev_set_doit,
>>> + .flags = RDMA_NL_ADMIN_PERM,
>>> + },
>>> [RDMA_NLDEV_CMD_PORT_GET] = {
>>> .doit = nldev_port_get_doit,
>>> .dump = nldev_port_get_dumpit,
>>> diff --git a/include/uapi/rdma/rdma_netlink.h b/include/uapi/rdma/rdma_netlink.h
>>> index edba6351ac13..f9c41bf59efc 100644
>>> --- a/include/uapi/rdma/rdma_netlink.h
>>> +++ b/include/uapi/rdma/rdma_netlink.h
>>> @@ -227,8 +227,9 @@ enum rdma_nldev_command {
>>> RDMA_NLDEV_CMD_UNSPEC,
>>>
>>> RDMA_NLDEV_CMD_GET, /* can dump */
>>> + RDMA_NLDEV_CMD_SET,
>>>
>>> - /* 2 - 4 are free to use */
>>> + /* 3 - 4 are free to use */
>>>
>>> RDMA_NLDEV_CMD_PORT_GET = 5, /* can dump */
>>>
>>>
>>
>> Mark
