static void coroutine_fn v9fs_link(void *opaque)
{
    V9fsPDU *pdu = opaque;
    int32_t dfid, oldfid;
    V9fsFidState *dfidp, *oldfidp;
    V9fsString name;
    size_t offset = 7;
    int err = 0;

    v9fs_string_init(&name);
    err = pdu_unmarshal(pdu, offset, "dds", &dfid, &oldfid, &name);
    if (err < 0) {
        goto out_nofid;
    }
    trace_v9fs_link(pdu->tag, pdu->id, dfid, oldfid, name.data);

    if (name_is_illegal(name.data)) {
        err = -ENOENT;
        goto out_nofid;
    }

    if (!strcmp(".", name.data) || !strcmp("..", name.data)) {
        err = -EEXIST;
        goto out_nofid;
    }

    dfidp = get_fid(pdu, dfid);
    if (dfidp == NULL) {
        err = -ENOENT;
        goto out_nofid;
    }

    oldfidp = get_fid(pdu, oldfid);
    if (oldfidp == NULL) {
        err = -ENOENT;
        goto out;
    }
    err = v9fs_co_link(pdu, oldfidp, dfidp, &name);
    if (!err) {
        err = offset;
    }
out:
    put_fid(pdu, dfidp);
out_nofid:
    v9fs_string_free(&name);
    pdu_complete(pdu, err);
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.