The following commit has been merged in the master branch: commit a07ea4d9941af5a0c6f0be2a71b51ac9c083c5e5 Author: Johannes Berg johannes.berg@intel.com Date: Mon Oct 24 14:40:02 2016 +0200

genetlink: no longer support using static family IDs

Static family IDs have never really been used, the only use case was the workaround I introduced for those users that assumed their family ID was also their multicast group ID.

Additionally, because static family IDs would never be reserved by the generic netlink code, using a relatively low ID would only work for built-in families that can be registered immediately after generic netlink is started, which is basically only the control family (apart from the workaround code, which I also had to add code for so it would reserve those IDs)

Thus, anything other than GENL_ID_GENERATE is flawed and luckily not used except in the cases I mentioned. Move those workarounds into a few lines of code, and then get rid of GENL_ID_GENERATE entirely, making it more robust.

Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: David S. Miller davem@davemloft.net

diff --git a/drivers/acpi/event.c b/drivers/acpi/event.c index e24ea4e..8dfca3d 100644 --- a/drivers/acpi/event.c +++ b/drivers/acpi/event.c @@ -83,7 +83,6 @@ static const struct genl_multicast_group acpi_event_mcgrps[] = { };

static struct genl_family acpi_event_genl_family = { - .id = GENL_ID_GENERATE, .name = ACPI_GENL_FAMILY_NAME, .version = ACPI_GENL_VERSION, .maxattr = ACPI_GENL_ATTR_MAX, diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c index 97e0cbc..f66737b 100644 --- a/drivers/net/gtp.c +++ b/drivers/net/gtp.c @@ -1095,7 +1095,6 @@ static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info) }

static struct genl_family gtp_genl_family = { - .id = GENL_ID_GENERATE, .name = "gtp", .version = 0, .hdrsize = 0, diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index 1a134cb..a5309b8 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -1422,7 +1422,6 @@ static void clear_tx_sa(struct macsec_tx_sa *tx_sa) }

static struct genl_family macsec_fam = { - .id = GENL_ID_GENERATE, .name = MACSEC_GENL_NAME, .hdrsize = 0, .version = MACSEC_GENL_VERSION, diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c index a380649..0b50205 100644 --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -2151,7 +2151,6 @@ static struct rtnl_link_ops team_link_ops __read_mostly = { ***********************************/

static struct genl_family team_nl_family = { - .id = GENL_ID_GENERATE, .name = TEAM_GENL_NAME, .version = TEAM_GENL_VERSION, .maxattr = TEAM_ATTR_MAX, diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c index e95b79b..54b6cd6 100644 --- a/drivers/net/wireless/mac80211_hwsim.c +++ b/drivers/net/wireless/mac80211_hwsim.c @@ -589,7 +589,6 @@ struct hwsim_radiotap_ack_hdr {

/* MAC80211_HWSIM netlinf family */ static struct genl_family hwsim_genl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = "MAC80211_HWSIM", .version = 1, diff --git a/drivers/scsi/pmcraid.c b/drivers/scsi/pmcraid.c index 68a5c34..cc50eb8 100644 --- a/drivers/scsi/pmcraid.c +++ b/drivers/scsi/pmcraid.c @@ -1369,12 +1369,6 @@ static struct genl_multicast_group pmcraid_mcgrps[] = { };

static struct genl_family pmcraid_event_family = { - /* - * Due to prior multicast group abuse (the code having assumed that - * the family ID can be used as a multicast group ID) we need to - * statically allocate a family (and thus group) ID. - */ - .id = GENL_ID_PMCRAID, .name = "pmcraid", .version = 1, .maxattr = PMCRAID_AEN_ATTR_MAX, diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 62bf4fe..313a0ef 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -148,7 +148,6 @@ static const struct genl_multicast_group tcmu_mcgrps[] = {

/* Our generic netlink family */ static struct genl_family tcmu_genl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = "TCM-USER", .version = 1, diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index 226b0b4ac..68d7503 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -2164,7 +2164,6 @@ static const struct genl_multicast_group thermal_event_mcgrps[] = { };

static struct genl_family thermal_event_genl_family = { - .id = GENL_ID_GENERATE, .name = THERMAL_GENL_FAMILY_NAME, .version = THERMAL_GENL_VERSION, .maxattr = THERMAL_GENL_ATTR_MAX, diff --git a/fs/dlm/netlink.c b/fs/dlm/netlink.c index 1e6e227..00d2269 100644 --- a/fs/dlm/netlink.c +++ b/fs/dlm/netlink.c @@ -17,7 +17,6 @@ static uint32_t dlm_nl_seqnum; static uint32_t listener_nlportid;

static struct genl_family family = { - .id = GENL_ID_GENERATE, .name = DLM_GENL_NAME, .version = DLM_GENL_VERSION, }; diff --git a/fs/quota/netlink.c b/fs/quota/netlink.c index 8b25267..3965a5c 100644 --- a/fs/quota/netlink.c +++ b/fs/quota/netlink.c @@ -13,13 +13,6 @@ static const struct genl_multicast_group quota_mcgrps[] = {

/* Netlink family structure for quota */ static struct genl_family quota_genl_family = { - /* - * Needed due to multicast group ID abuse - old code assumed - * the family ID was also a valid multicast group ID (which - * isn't true) and userspace might thus rely on it. Assign a - * static ID for this group to make dealing with that easier. - */ - .id = GENL_ID_VFS_DQUOT, .hdrsize = 0, .name = "VFS_DQUOT", .version = 1, diff --git a/include/linux/genl_magic_func.h b/include/linux/genl_magic_func.h index 667c311..7c070c1 100644 --- a/include/linux/genl_magic_func.h +++ b/include/linux/genl_magic_func.h @@ -260,7 +260,6 @@ static struct genl_ops ZZZ_genl_ops[] __read_mostly = { */ #define ZZZ_genl_family CONCAT_(GENL_MAGIC_FAMILY, _genl_family) static struct genl_family ZZZ_genl_family __read_mostly = { - .id = GENL_ID_GENERATE, .name = __stringify(GENL_MAGIC_FAMILY), .version = GENL_MAGIC_VERSION, #ifdef GENL_MAGIC_FAMILY_HDRSZ diff --git a/include/net/genetlink.h b/include/net/genetlink.h index ef9defb..43a5c39 100644 --- a/include/net/genetlink.h +++ b/include/net/genetlink.h @@ -20,7 +20,7 @@ struct genl_info;

/** * struct genl_family - generic netlink family - * @id: protocol family idenfitier + * @id: protocol family identifier (private) * @hdrsize: length of user specific header in bytes * @name: name of family * @version: protocol version @@ -48,7 +48,7 @@ struct genl_info; * @n_ops: number of operations supported by this family (private) */ struct genl_family { - unsigned int id; + unsigned int id; /* private */ unsigned int hdrsize; char name[GENL_NAMSIZ]; unsigned int version; @@ -149,9 +149,6 @@ static inline int genl_register_family(struct genl_family *family) * Registers the specified family and operations from the specified table. * Only one family may be registered with the same family name or identifier. * - * The family id may equal GENL_ID_GENERATE causing an unique id to - * be automatically generated and assigned. - * * Either a doit or dumpit callback must be specified for every registered * operation or the function will fail. Only one operation structure per * command identifier may be registered. diff --git a/include/uapi/linux/genetlink.h b/include/uapi/linux/genetlink.h index 5512c90..d9b2db4 100644 --- a/include/uapi/linux/genetlink.h +++ b/include/uapi/linux/genetlink.h @@ -26,7 +26,6 @@ struct genlmsghdr { /* * List of reserved static generic netlink identifiers: */ -#define GENL_ID_GENERATE 0 #define GENL_ID_CTRL NLMSG_MIN_TYPE #define GENL_ID_VFS_DQUOT (NLMSG_MIN_TYPE + 1) #define GENL_ID_PMCRAID (NLMSG_MIN_TYPE + 2) diff --git a/kernel/taskstats.c b/kernel/taskstats.c index b3f05ee..d7a1a94 100644 --- a/kernel/taskstats.c +++ b/kernel/taskstats.c @@ -42,7 +42,6 @@ static int family_registered; struct kmem_cache *taskstats_cache;

static struct genl_family family = { - .id = GENL_ID_GENERATE, .name = TASKSTATS_GENL_NAME, .version = TASKSTATS_GENL_VERSION, .maxattr = TASKSTATS_CMD_ATTR_MAX, diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c index 64cb6ac..a03b0ed 100644 --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -49,7 +49,6 @@ #include "translation-table.h"

struct genl_family batadv_netlink_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = BATADV_NL_NAME, .version = 1, diff --git a/net/core/devlink.c b/net/core/devlink.c index d2fd736..3008d9c 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -342,7 +342,6 @@ static void devlink_nl_post_doit(const struct genl_ops *ops, }

static struct genl_family devlink_nl_family = { - .id = GENL_ID_GENERATE, .name = DEVLINK_GENL_NAME, .version = DEVLINK_GENL_VERSION, .maxattr = DEVLINK_ATTR_MAX, diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c index 72cfb0c..a5320df 100644 --- a/net/core/drop_monitor.c +++ b/net/core/drop_monitor.c @@ -60,7 +60,6 @@ struct dm_hw_stat_delta { };

static struct genl_family net_drop_monitor_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = "NET_DM", .version = 2, diff --git a/net/hsr/hsr_netlink.c b/net/hsr/hsr_netlink.c index d4d1617..2ad0394 100644 --- a/net/hsr/hsr_netlink.c +++ b/net/hsr/hsr_netlink.c @@ -132,7 +132,6 @@ static const struct nla_policy hsr_genl_policy[HSR_A_MAX + 1] = { };

static struct genl_family hsr_genl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = "HSR", .version = 1, diff --git a/net/ieee802154/netlink.c b/net/ieee802154/netlink.c index c8133c0..1914415 100644 --- a/net/ieee802154/netlink.c +++ b/net/ieee802154/netlink.c @@ -29,7 +29,6 @@ static unsigned int ieee802154_seq_num; static DEFINE_SPINLOCK(ieee802154_seq_lock);

struct genl_family nl802154_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = IEEE802154_NL_NAME, .version = 1, diff --git a/net/ieee802154/nl802154.c b/net/ieee802154/nl802154.c index 21aabad..1822998 100644 --- a/net/ieee802154/nl802154.c +++ b/net/ieee802154/nl802154.c @@ -34,7 +34,6 @@ static void nl802154_post_doit(const struct genl_ops *ops, struct sk_buff *skb,

/* the netlink family */ static struct genl_family nl802154_fam = { - .id = GENL_ID_GENERATE, /* don't bother with a hardcoded ID */ .name = NL802154_GENL_NAME, /* have users key off the name instead */ .hdrsize = 0, /* no private header */ .version = 1, /* no particular meaning now */ diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c index cf50f7e..e3fc527 100644 --- a/net/ipv4/fou.c +++ b/net/ipv4/fou.c @@ -623,7 +623,6 @@ static int fou_destroy(struct net *net, struct fou_cfg *cfg) }

static struct genl_family fou_nl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = FOU_GENL_NAME, .version = FOU_GENL_VERSION, diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c index bf1f3b2..3da3051 100644 --- a/net/ipv4/tcp_metrics.c +++ b/net/ipv4/tcp_metrics.c @@ -743,7 +743,6 @@ void tcp_fastopen_cache_set(struct sock *sk, u16 mss, }

static struct genl_family tcp_metrics_nl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = TCP_METRICS_GENL_NAME, .version = TCP_METRICS_GENL_VERSION, diff --git a/net/ipv6/ila/ila_xlat.c b/net/ipv6/ila/ila_xlat.c index e604013..0d57e27 100644 --- a/net/ipv6/ila/ila_xlat.c +++ b/net/ipv6/ila/ila_xlat.c @@ -119,7 +119,6 @@ static const struct rhashtable_params rht_params = { };

static struct genl_family ila_nl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = ILA_GENL_NAME, .version = ILA_GENL_VERSION, diff --git a/net/irda/irnetlink.c b/net/irda/irnetlink.c index e15c40e..f23b81a 100644 --- a/net/irda/irnetlink.c +++ b/net/irda/irnetlink.c @@ -25,7 +25,6 @@

static struct genl_family irda_nl_family = { - .id = GENL_ID_GENERATE, .name = IRDA_NL_NAME, .hdrsize = 0, .version = IRDA_NL_VERSION, diff --git a/net/l2tp/l2tp_netlink.c b/net/l2tp/l2tp_netlink.c index bf31177..4fbf1f4 100644 --- a/net/l2tp/l2tp_netlink.c +++ b/net/l2tp/l2tp_netlink.c @@ -32,7 +32,6 @@

static struct genl_family l2tp_nl_family = { - .id = GENL_ID_GENERATE, .name = L2TP_GENL_NAME, .version = L2TP_GENL_VERSION, .hdrsize = 0, diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c index c3c809b..ceed66c 100644 --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -2841,7 +2841,6 @@ static struct nf_sockopt_ops ip_vs_sockopts = {

/* IPVS genetlink family */ static struct genl_family ip_vs_genl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = IPVS_GENL_NAME, .version = IPVS_GENL_VERSION, diff --git a/net/netlabel/netlabel_calipso.c b/net/netlabel/netlabel_calipso.c index 2ec93c5..152e503 100644 --- a/net/netlabel/netlabel_calipso.c +++ b/net/netlabel/netlabel_calipso.c @@ -61,7 +61,6 @@ struct netlbl_domhsh_walk_arg {

/* NetLabel Generic NETLINK CALIPSO family */ static struct genl_family netlbl_calipso_gnl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = NETLBL_NLTYPE_CALIPSO_NAME, .version = NETLBL_PROTO_VERSION, diff --git a/net/netlabel/netlabel_cipso_v4.c b/net/netlabel/netlabel_cipso_v4.c index 7fd1104..755b284 100644 --- a/net/netlabel/netlabel_cipso_v4.c +++ b/net/netlabel/netlabel_cipso_v4.c @@ -60,7 +60,6 @@ struct netlbl_domhsh_walk_arg {

/* NetLabel Generic NETLINK CIPSOv4 family */ static struct genl_family netlbl_cipsov4_gnl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = NETLBL_NLTYPE_CIPSOV4_NAME, .version = NETLBL_PROTO_VERSION, diff --git a/net/netlabel/netlabel_mgmt.c b/net/netlabel/netlabel_mgmt.c index f85d0e0..3b00f23 100644 --- a/net/netlabel/netlabel_mgmt.c +++ b/net/netlabel/netlabel_mgmt.c @@ -61,7 +61,6 @@ struct netlbl_domhsh_walk_arg {

/* NetLabel Generic NETLINK CIPSOv4 family */ static struct genl_family netlbl_mgmt_gnl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = NETLBL_NLTYPE_MGMT_NAME, .version = NETLBL_PROTO_VERSION, diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c index 4528cff..c2ea8d1 100644 --- a/net/netlabel/netlabel_unlabeled.c +++ b/net/netlabel/netlabel_unlabeled.c @@ -124,7 +124,6 @@ static u8 netlabel_unlabel_acceptflg;

/* NetLabel Generic NETLINK unlabeled family */ static struct genl_family netlbl_unlabel_gnl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = NETLBL_NLTYPE_UNLABELED_NAME, .version = NETLBL_PROTO_VERSION, diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 01291b7..f19ec96 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -349,8 +349,6 @@ static int genl_validate_ops(const struct genl_family *family) * * Registers the specified family after validating it first. Only one * family may be registered with the same family name or identifier. - * The family id may equal GENL_ID_GENERATE causing an unique id to - * be automatically generated and assigned. * * The family's ops array must already be assigned, you can use the * genl_register_family_with_ops() helper function. @@ -359,13 +357,7 @@ static int genl_validate_ops(const struct genl_family *family) */ int __genl_register_family(struct genl_family *family) { - int err = -EINVAL, i; - - if (family->id && family->id < GENL_MIN_ID) - goto errout; - - if (family->id > GENL_MAX_ID) - goto errout; + int err, i;

err = genl_validate_ops(family); if (err) @@ -378,8 +370,27 @@ int __genl_register_family(struct genl_family *family) goto errout_locked; }

- if (family->id == GENL_ID_GENERATE) { - u16 newid = genl_generate_id(); + if (family == &genl_ctrl) { + family->id = GENL_ID_CTRL; + } else { + u16 newid; + + /* this should be left zero in the struct */ + WARN_ON(family->id); + + /* + * Sadly, a few cases need to be special-cased + * due to them having previously abused the API + * and having used their family ID also as their + * multicast group ID, so we use reserved IDs + * for both to be sure we can do that mapping. + */ + if (strcmp(family->name, "pmcraid") == 0) + newid = GENL_ID_PMCRAID; + else if (strcmp(family->name, "VFS_DQUOT") == 0) + newid = GENL_ID_VFS_DQUOT; + else + newid = genl_generate_id();

if (!newid) { err = -ENOMEM; @@ -387,9 +398,6 @@ int __genl_register_family(struct genl_family *family) }

family->id = newid; - } else if (genl_family_find_byid(family->id)) { - err = -EEXIST; - goto errout_locked; }

if (family->maxattr && !family->parallel_ops) { @@ -419,7 +427,6 @@ int __genl_register_family(struct genl_family *family)

errout_locked: genl_unlock_all(); -errout: return err; } EXPORT_SYMBOL(__genl_register_family); diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c index 79786bf..c230403 100644 --- a/net/nfc/netlink.c +++ b/net/nfc/netlink.c @@ -39,7 +39,6 @@ static const struct genl_multicast_group nfc_genl_mcgrps[] = { };

static struct genl_family nfc_genl_family = { - .id = GENL_ID_GENERATE, .hdrsize = 0, .name = NFC_GENL_NAME, .version = NFC_GENL_VERSION, diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index 194435a..f9fef7d 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -671,7 +671,6 @@ static const struct genl_ops dp_packet_genl_ops[] = { };

static struct genl_family dp_packet_genl_family = { - .id = GENL_ID_GENERATE, .hdrsize = sizeof(struct ovs_header), .name = OVS_PACKET_FAMILY, .version = OVS_PACKET_VERSION, @@ -1436,7 +1435,6 @@ static const struct genl_ops dp_flow_genl_ops[] = { };

static struct genl_family dp_flow_genl_family = { - .id = GENL_ID_GENERATE, .hdrsize = sizeof(struct ovs_header), .name = OVS_FLOW_FAMILY, .version = OVS_FLOW_VERSION, @@ -1822,7 +1820,6 @@ static const struct genl_ops dp_datapath_genl_ops[] = { };

static struct genl_family dp_datapath_genl_family = { - .id = GENL_ID_GENERATE, .hdrsize = sizeof(struct ovs_header), .name = OVS_DATAPATH_FAMILY, .version = OVS_DATAPATH_VERSION, @@ -2244,7 +2241,6 @@ static const struct genl_ops dp_vport_genl_ops[] = { };

struct genl_family dp_vport_genl_family = { - .id = GENL_ID_GENERATE, .hdrsize = sizeof(struct ovs_header), .name = OVS_VPORT_FAMILY, .version = OVS_VPORT_VERSION, diff --git a/net/tipc/netlink.c b/net/tipc/netlink.c index 4b94f3c..383b8fe 100644 --- a/net/tipc/netlink.c +++ b/net/tipc/netlink.c @@ -136,7 +136,6 @@ const struct nla_policy tipc_nl_udp_policy[TIPC_NLA_UDP_MAX + 1] = { * so we have a separate genl handling for the new API. */ struct genl_family tipc_genl_family = { - .id = GENL_ID_GENERATE, .name = TIPC_GENL_V2_NAME, .version = TIPC_GENL_V2_VERSION, .hdrsize = 0, diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c index 1fd4647..f04428e 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -1216,7 +1216,6 @@ send: }

static struct genl_family tipc_genl_compat_family = { - .id = GENL_ID_GENERATE, .name = TIPC_GENL_NAME, .version = TIPC_GENL_VERSION, .hdrsize = TIPC_GENL_HDRLEN, diff --git a/net/wimax/stack.c b/net/wimax/stack.c index 3f816e2..8ac83a4 100644 --- a/net/wimax/stack.c +++ b/net/wimax/stack.c @@ -573,7 +573,6 @@ size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL);

struct genl_family wimax_gnl_family = { - .id = GENL_ID_GENERATE, .name = "WiMAX", .version = WIMAX_GNL_VERSION, .hdrsize = 0, diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 7d8cb33..714beaf 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -39,7 +39,6 @@ static void nl80211_post_doit(const struct genl_ops *ops, struct sk_buff *skb,

/* the netlink family */ static struct genl_family nl80211_fam = { - .id = GENL_ID_GENERATE, /* don't bother with a hardcoded ID */ .name = NL80211_GENL_NAME, /* have users key off the name instead */ .hdrsize = 0, /* no private header */ .version = 1, /* no particular meaning now */