linux/fs/cifs/netlink.c
Jakub Kicinski 9c5d03d362 genetlink: start to validate reserved header bytes
We had historically not checked that genlmsghdr.reserved
is 0 on input which prevents us from using those precious
bytes in the future.

One use case would be to extend the cmd field, which is
currently just 8 bits wide and 256 is not a lot of commands
for some core families.

To make sure that new families do the right thing by default
put the onus of opting out of validation on existing families.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com> (NetLabel)
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-29 12:47:15 +01:00

91 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Netlink routines for CIFS
*
* Copyright (c) 2020 Samuel Cabrero <scabrero@suse.de>
*/
#include <net/genetlink.h>
#include <uapi/linux/cifs/cifs_netlink.h>
#include "netlink.h"
#include "cifsglob.h"
#include "cifs_debug.h"
#include "cifs_swn.h"
static const struct nla_policy cifs_genl_policy[CIFS_GENL_ATTR_MAX + 1] = {
[CIFS_GENL_ATTR_SWN_REGISTRATION_ID] = { .type = NLA_U32 },
[CIFS_GENL_ATTR_SWN_NET_NAME] = { .type = NLA_STRING },
[CIFS_GENL_ATTR_SWN_SHARE_NAME] = { .type = NLA_STRING },
[CIFS_GENL_ATTR_SWN_IP] = { .len = sizeof(struct sockaddr_storage) },
[CIFS_GENL_ATTR_SWN_NET_NAME_NOTIFY] = { .type = NLA_FLAG },
[CIFS_GENL_ATTR_SWN_SHARE_NAME_NOTIFY] = { .type = NLA_FLAG },
[CIFS_GENL_ATTR_SWN_IP_NOTIFY] = { .type = NLA_FLAG },
[CIFS_GENL_ATTR_SWN_KRB_AUTH] = { .type = NLA_FLAG },
[CIFS_GENL_ATTR_SWN_USER_NAME] = { .type = NLA_STRING },
[CIFS_GENL_ATTR_SWN_PASSWORD] = { .type = NLA_STRING },
[CIFS_GENL_ATTR_SWN_DOMAIN_NAME] = { .type = NLA_STRING },
[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE] = { .type = NLA_U32 },
[CIFS_GENL_ATTR_SWN_RESOURCE_STATE] = { .type = NLA_U32 },
[CIFS_GENL_ATTR_SWN_RESOURCE_NAME] = { .type = NLA_STRING},
};
static const struct genl_ops cifs_genl_ops[] = {
{
.cmd = CIFS_GENL_CMD_SWN_NOTIFY,
.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
.doit = cifs_swn_notify,
},
};
static const struct genl_multicast_group cifs_genl_mcgrps[] = {
[CIFS_GENL_MCGRP_SWN] = { .name = CIFS_GENL_MCGRP_SWN_NAME },
};
struct genl_family cifs_genl_family = {
.name = CIFS_GENL_NAME,
.version = CIFS_GENL_VERSION,
.hdrsize = 0,
.maxattr = CIFS_GENL_ATTR_MAX,
.module = THIS_MODULE,
.policy = cifs_genl_policy,
.ops = cifs_genl_ops,
.n_ops = ARRAY_SIZE(cifs_genl_ops),
.resv_start_op = CIFS_GENL_CMD_SWN_NOTIFY + 1,
.mcgrps = cifs_genl_mcgrps,
.n_mcgrps = ARRAY_SIZE(cifs_genl_mcgrps),
};
/**
* cifs_genl_init - Register generic netlink family
*
* Return zero if initialized successfully, otherwise non-zero.
*/
int cifs_genl_init(void)
{
int ret;
ret = genl_register_family(&cifs_genl_family);
if (ret < 0) {
cifs_dbg(VFS, "%s: failed to register netlink family\n",
__func__);
return ret;
}
return 0;
}
/**
* cifs_genl_exit - Unregister generic netlink family
*/
void cifs_genl_exit(void)
{
int ret;
ret = genl_unregister_family(&cifs_genl_family);
if (ret < 0) {
cifs_dbg(VFS, "%s: failed to unregister netlink family\n",
__func__);
}
}