[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [libvirt] [PATCHv2 2/5] domifaddr: Implement the remote protocol



On Thu, Aug 15, 2013 at 02:24:27AM +0530, nehaljwani wrote:
> Implement RPC calls for virDomainInterfacesAddresses
> 
> daemon/remote.c
>    * Define remoteSerializeDomainInterfacePtr, remoteDispatchDomainInterfacesAddresses
> 
> src/remote/remote_driver.c
>    * Define remoteDomainInterfacesAddresses
> 
> src/remote/remote_protocol.x
>    * New RPC procedure: REMOTE_PROC_DOMAIN_INTERFACES_ADDRESSES
>    * Define structs remote_domain_ip_addr, remote_domain_interface,
>      remote_domain_interfaces_addresses_args, remote_domain_interfaces_addresses_ret
> 
> src/remote_protocol-structs
>    * New structs added
> 
> ---
>  daemon/remote.c              | 122 +++++++++++++++++++++++++++++++++++++++++++
>  src/remote/remote_driver.c   |  88 +++++++++++++++++++++++++++++++
>  src/remote/remote_protocol.x |  30 ++++++++++-
>  src/remote_protocol-structs  |  24 +++++++++
>  4 files changed, 263 insertions(+), 1 deletion(-)
> 
> diff --git a/daemon/remote.c b/daemon/remote.c
> index 03d5557..9d8651c 100644
> --- a/daemon/remote.c
> +++ b/daemon/remote.c
> @@ -5025,7 +5025,129 @@ cleanup:
>      return rv;
>  }
>  
> +static int
> +remoteSerializeDomainInterfacePtr(virDomainInterfacePtr ifaces,
> +                                  unsigned int ifaces_count,
> +                                  remote_domain_interfaces_addresses_ret *ret)
> +{
> +    size_t i, j;
> +
> +    if (VIR_ALLOC_N(ret->ifaces.ifaces_val, ifaces_count) < 0)
> +        return -1;

You *must* check upper bound of ifaces_count before allocating memory - this
value is untrusted data.

> +
> +    ret->ifaces.ifaces_len = ifaces_count;
> +
> +    for (i = 0; i < ifaces_count; i++) {
> +        virDomainInterfacePtr iface = &(ifaces[i]);
> +        remote_domain_interface *iface_ret = &(ret->ifaces.ifaces_val[i]);
> +
> +        if ((VIR_STRDUP(iface_ret->name, iface->name)) < 0)
> +            goto no_memory;
> +
> +        if (iface->hwaddr) {
> +            char **hwaddr_p = NULL;
> +            if (VIR_ALLOC(hwaddr_p) < 0)
> +                goto no_memory;
> +            if (VIR_STRDUP(*hwaddr_p, iface->hwaddr) < 0) {
> +                VIR_FREE(hwaddr_p);
> +                goto no_memory;
> +            }
> +
> +            iface_ret->hwaddr = hwaddr_p;
> +        }
> +
> +        if (VIR_ALLOC_N(iface_ret->ip_addrs.ip_addrs_val,
> +                        iface->ip_addrs_count) < 0)
> +            goto no_memory;

Again  ip_addrs_count is untrusted data so must have an upper
bound checked.

> +
> +        iface_ret->ip_addrs.ip_addrs_len = iface->ip_addrs_count;
> +
> +        for (j = 0; j < iface->ip_addrs_count; j++) {
> +            virDomainIPAddressPtr ip_addr = &(iface->ip_addrs[j]);
> +            remote_domain_ip_addr *ip_addr_ret =
> +                &(iface_ret->ip_addrs.ip_addrs_val[j]);
> +
> +            if (VIR_STRDUP(ip_addr_ret->addr, ip_addr->addr) < 0)
> +                goto no_memory;
> +
> +            ip_addr_ret->prefix = ip_addr->prefix;
> +            ip_addr_ret->type = ip_addr->type;
> +        }
> +    }
> +
> +    return 0;
> +
> +no_memory:
> +    if (ret->ifaces.ifaces_val) {
> +        for (i = 0; i < ifaces_count; i++) {
> +            remote_domain_interface *iface_ret = &(ret->ifaces.ifaces_val[i]);
> +            VIR_FREE(iface_ret->name);
> +            VIR_FREE(iface_ret->hwaddr);
> +            for (j = 0; j < iface_ret->ip_addrs.ip_addrs_len; j++) {
> +                remote_domain_ip_addr *ip_addr =
> +                    &(iface_ret->ip_addrs.ip_addrs_val[j]);
> +                VIR_FREE(ip_addr->addr);
> +            }
> +            VIR_FREE(iface_ret);
> +        }
> +        VIR_FREE(ret->ifaces.ifaces_val);
> +    }
>  
> +    return -1;
> +}
> +
> +static int
> +remoteDispatchDomainInterfacesAddresses(
> +    virNetServerPtr server ATTRIBUTE_UNUSED,
> +    virNetServerClientPtr client,
> +    virNetMessagePtr msg ATTRIBUTE_UNUSED,
> +    virNetMessageErrorPtr rerr,
> +    remote_domain_interfaces_addresses_args *args,
> +    remote_domain_interfaces_addresses_ret *ret)
> +{
> +    int rv = -1;
> +    virDomainPtr dom = NULL;
> +    virDomainInterfacePtr ifaces = NULL;
> +    unsigned int ifaces_count = 0;
> +    struct daemonClientPrivate *priv =
> +        virNetServerClientGetPrivateData(client);
> +
> +    if (!priv->conn) {
> +        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("connection not open"));
> +        goto cleanup;
> +    }
> +
> +    if (!(dom = get_nonnull_domain(priv->conn, args->dom)))
> +        goto cleanup;
> +
> +    if (virDomainInterfacesAddresses(dom, &ifaces,
> +                                     &ifaces_count, args->flags) < 0)
> +        goto cleanup;
> +
> +    if (remoteSerializeDomainInterfacePtr(ifaces, ifaces_count, ret) < 0)
> +        goto cleanup;
> +
> +    rv = 0;
> +
> +cleanup:
> +    if (rv < 0)
> +        virNetMessageSaveError(rerr);
> +    if (dom)
> +        virDomainFree(dom);
> +    if (ifaces) {
> +        size_t i, j;
> +
> +        for (i = 0; i < ifaces_count; i++) {
> +            VIR_FREE(ifaces[i].name);
> +            VIR_FREE(ifaces[i].hwaddr);
> +            for (j = 0; j < ifaces[i].ip_addrs_count; j++)
> +                VIR_FREE(ifaces[i].ip_addrs[j].addr);
> +            VIR_FREE(ifaces[i].ip_addrs);
> +        }
> +        VIR_FREE(ifaces);
> +    }
> +    return rv;
> +}
>  
>  /*----- Helpers. -----*/
>  

> +cleanup:
> +    if (rv < 0) {
> +        for (i = 0; i < *ifaces_count; i++) {
> +            VIR_FREE((*ifaces)[i].name);
> +            VIR_FREE((*ifaces)[i].hwaddr);
> +            for (j = 0; j < (*ifaces)[i].ip_addrs_count; j++)
> +                VIR_FREE((*ifaces)[i].ip_addrs[j].addr);
> +            VIR_FREE((*ifaces)[i].ip_addrs);
> +        }
> +        VIR_FREE(*ifaces);

This horrible code is repeated soo many times - just reinforces my
point on the previous patch about providing a function to hide this.

> +    }
> +    xdr_free((xdrproc_t)xdr_remote_domain_interfaces_addresses_ret,
> +             (char *) &ret);
> +done:
> +    remoteDriverUnlock(priv);
> +    return rv;
> +}
> +
>  static void
>  remoteDomainEventQueue(struct private_data *priv, virDomainEventPtr event)
>  {
> @@ -6811,6 +6898,7 @@ static virDriver remote_driver = {
>      .domainMigratePerform3Params = remoteDomainMigratePerform3Params, /* 1.1.0 */
>      .domainMigrateFinish3Params = remoteDomainMigrateFinish3Params, /* 1.1.0 */
>      .domainMigrateConfirm3Params = remoteDomainMigrateConfirm3Params, /* 1.1.0 */
> +    .domainInterfacesAddresses = remoteDomainInterfacesAddresses, /* 1.1.2 */
>  };
>  
>  static virNetworkDriver network_driver = {
> diff --git a/src/remote/remote_protocol.x b/src/remote/remote_protocol.x
> index 7cfebdf..06929e7 100644
> --- a/src/remote/remote_protocol.x
> +++ b/src/remote/remote_protocol.x
> @@ -2837,6 +2837,27 @@ struct remote_domain_event_device_removed_msg {
>      remote_nonnull_string devAlias;
>  };
>  
> +struct remote_domain_ip_addr {
> +    int type;
> +    remote_nonnull_string addr;
> +    int prefix;
> +};
> +
> +struct remote_domain_interface {
> +    remote_nonnull_string name;
> +    remote_string hwaddr;
> +    remote_domain_ip_addr ip_addrs<>;

Use of <> *NOT* allowed - this is a security flaw allowing the client
to trigger DOS on libvirtd allocating memory. Follow the examples of
other APis which set an explicit limit.

> +};
> +
> +struct remote_domain_interfaces_addresses_args {
> +    remote_nonnull_domain dom;
> +    unsigned int flags;
> +};
> +
> +struct remote_domain_interfaces_addresses_ret {
> +    remote_domain_interface ifaces<>;

Again, this is flawed.

Daniel
-- 
|: http://berrange.com      -o-    http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org              -o-             http://virt-manager.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org       -o-       http://live.gnome.org/gtk-vnc :|


[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]