[bug report] nvme-fc: improve memory usage in nvme_fc_rcv_ls_req()

[Dan Carpenter <error27@gmail.com>]

Hello Christophe JAILLET,

The patch cf3d00840170: "nvme-fc: improve memory usage in
nvme_fc_rcv_ls_req()" from Oct 2, 2022, leads to the following Smatch
static checker warning:

drivers/nvme/host/fc.c:1757 nvme_fc_rcv_ls_req() error: potential null dereference 'lsop'.  (kzalloc returns null)
drivers/nvme/host/fc.c:1759 nvme_fc_rcv_ls_req() warn: variable dereferenced before check 'lsop' (see line 1757)

drivers/nvme/host/fc.c
    1747         if (lsreqbuf_len > sizeof(union nvmefc_ls_requests)) {
    1748                 dev_info(lport->dev,
    1749                         "RCV %s LS failed: payload too large\n",
    1750                         (w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
    1751                                 nvmefc_ls_names[w0->ls_cmd] : "");
    1752                 ret = -E2BIG;
    1753                 goto out_put;
    1754         }
    1755 
    1756         lsop = kzalloc(sizeof(*lsop), GFP_KERNEL);
--> 1757         lsop->rqstbuf = kzalloc(sizeof(*lsop->rqstbuf), GFP_KERNEL);
                 ^^^^^^^^^^^^^

    1758         lsop->rspbuf = kzalloc(sizeof(*lsop->rspbuf), GFP_KERNEL);
    1759         if (!lsop || !lsop->rqstbuf || !lsop->rspbuf) {
                      ^^^^

    1760                 dev_info(lport->dev,
    1761                         "RCV %s LS failed: No memory\n",
    1762                         (w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
    1763                                 nvmefc_ls_names[w0->ls_cmd] : "");
    1764                 ret = -ENOMEM;
    1765                 goto out_free;
    1766         }
    1767 

regards,
dan carpenter