Subject: Re: [PATCH 10/12] nvmet: Implement basic In-Band Authentication
To:     Hannes Reinecke <hare@suse.de>
Cc:     Christoph Hellwig <hch@lst.de>, Keith Busch <keith.busch@wdc.com>,
        linux-nvme@lists.infradead.org,
        Herbert Xu <herberg@gondor.apana.org.au>,
        David Miller <davem@davemloft.org>,
        linux-crypto@vger.kernel.org
References: <20211122074727.25988-1-hare@suse.de>
 <20211122074727.25988-11-hare@suse.de>
 <762ce404-9035-30ca-078d-eb0b36223e4c@grimberg.me>
 <313b19d2-ea54-ce1c-f9cb-3f1fb6743787@suse.de>
From:   Sagi Grimberg <sagi@grimberg.me>
Message-ID: <891fe077-40d3-5bad-52fb-f0ee6f6107b6@grimberg.me>
Date:   Mon, 22 Nov 2021 16:00:13 +0200
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On 11/22/21 3:21 PM, Hannes Reinecke wrote:
> On 11/22/21 12:59 PM, Sagi Grimberg wrote:
>>
>>> +void nvmet_execute_auth_send(struct nvmet_req *req)
>>> +{
>>> +    struct nvmet_ctrl *ctrl = req->sq->ctrl;
>>> +    struct nvmf_auth_dhchap_success2_data *data;
>>> +    void *d;
>>> +    u32 tl;
>>> +    u16 status = 0;
>>> +
>>> +    if (req->cmd->auth_send.secp !=
>>> NVME_AUTH_DHCHAP_PROTOCOL_IDENTIFIER) {
>>> +        status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
>>> +        req->error_loc =
>>> +            offsetof(struct nvmf_auth_send_command, secp);
>>> +        goto done;
>>> +    }
>>> +    if (req->cmd->auth_send.spsp0 != 0x01) {
>>> +        status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
>>> +        req->error_loc =
>>> +            offsetof(struct nvmf_auth_send_command, spsp0);
>>> +        goto done;
>>> +    }
>>> +    if (req->cmd->auth_send.spsp1 != 0x01) {
>>> +        status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
>>> +        req->error_loc =
>>> +            offsetof(struct nvmf_auth_send_command, spsp1);
>>> +        goto done;
>>> +    }
>>> +    tl = le32_to_cpu(req->cmd->auth_send.tl);
>>> +    if (!tl) {
>>> +        status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
>>> +        req->error_loc =
>>> +            offsetof(struct nvmf_auth_send_command, tl);
>>> +        goto done;
>>> +    }
>>> +    if (!nvmet_check_transfer_len(req, tl)) {
>>> +        pr_debug("%s: transfer length mismatch (%u)\n", __func__, tl);
>>> +        return;
>>> +    }
>>> +
>>> +    d = kmalloc(tl, GFP_KERNEL);
>>> +    if (!d) {
>>> +        status = NVME_SC_INTERNAL;
>>> +        goto done;
>>> +    }
>>> +
>>> +    status = nvmet_copy_from_sgl(req, 0, d, tl);
>>> +    if (status) {
>>> +        kfree(d);
>>> +        goto done;
>>> +    }
>>> +
>>> +    data = d;
>>> +    pr_debug("%s: ctrl %d qid %d type %d id %d step %x\n", __func__,
>>> +         ctrl->cntlid, req->sq->qid, data->auth_type, data->auth_id,
>>> +         req->sq->dhchap_step);
>>> +    if (data->auth_type != NVME_AUTH_COMMON_MESSAGES &&
>>> +        data->auth_type != NVME_AUTH_DHCHAP_MESSAGES)
>>> +        goto done_failure1;
>>> +    if (data->auth_type == NVME_AUTH_COMMON_MESSAGES) {
>>> +        if (data->auth_id == NVME_AUTH_DHCHAP_MESSAGE_NEGOTIATE) {
>>> +            /* Restart negotiation */
>>> +            pr_debug("%s: ctrl %d qid %d reset negotiation\n", __func__,
>>> +                 ctrl->cntlid, req->sq->qid);
>>> +            if (!req->sq->qid) {
>>> +                status = nvmet_setup_auth(ctrl);
>>
>> Aren't you leaking memory here?
> 
> I've checked, and I _think_ everything is in order.
> Any particular concerns?
> ( 'd' is free at 'done_kfree', and we never exit without going through
> it AFAICS).
> Have I missed something?

You are calling nvmet_setup_auth for re-authentication, who is calling
nvmet_destroy_auth to free the controller auth stuff?

Don't you need something like:
--
		if (!req->sq->qid) {
			nvmet_destroy_auth(ctrl);
			status = nvmet_setup_auth(ctrl);
			...
		}
--