From af65bdfce98d7965fbe93a48b8128444a2eea024 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Fri, 20 Apr 2007 14:14:21 -0700 Subject: [PATCH] [NETLINK]: Switch cb_lock spinlock to mutex and allow to override it Switch cb_lock to mutex and allow netlink kernel users to override it with a subsystem specific mutex for consistent locking in dump callbacks. All netlink_dump_start users have been audited not to rely on any side-effects of the previously used spinlock. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- drivers/connector/connector.c | 2 +- drivers/scsi/scsi_netlink.c | 3 ++- drivers/scsi/scsi_transport_iscsi.c | 2 +- fs/ecryptfs/netlink.c | 2 +- include/linux/netlink.h | 5 +++- kernel/audit.c | 2 +- lib/kobject_uevent.c | 2 +- net/bridge/netfilter/ebt_ulog.c | 2 +- net/core/rtnetlink.c | 2 +- net/decnet/netfilter/dn_rtmsg.c | 2 +- net/ipv4/fib_frontend.c | 3 ++- net/ipv4/inet_diag.c | 2 +- net/ipv4/netfilter/ip_queue.c | 2 +- net/ipv4/netfilter/ipt_ULOG.c | 2 +- net/ipv6/netfilter/ip6_queue.c | 2 +- net/netfilter/nfnetlink.c | 2 +- net/netlink/af_netlink.c | 38 +++++++++++++++++------------ net/netlink/genetlink.c | 2 +- net/xfrm/xfrm_user.c | 2 +- security/selinux/netlink.c | 2 +- 20 files changed, 47 insertions(+), 34 deletions(-) diff --git a/drivers/connector/connector.c b/drivers/connector/connector.c index 7f9c4fb7e5b0..a7b9e9bb3e8d 100644 --- a/drivers/connector/connector.c +++ b/drivers/connector/connector.c @@ -448,7 +448,7 @@ static int __devinit cn_init(void) dev->nls = netlink_kernel_create(NETLINK_CONNECTOR, CN_NETLINK_USERS + 0xf, - dev->input, THIS_MODULE); + dev->input, NULL, THIS_MODULE); if (!dev->nls) return -EIO; diff --git a/drivers/scsi/scsi_netlink.c b/drivers/scsi/scsi_netlink.c index 45646a285244..4bf9aa547c78 100644 --- a/drivers/scsi/scsi_netlink.c +++ b/drivers/scsi/scsi_netlink.c @@ -168,7 +168,8 @@ scsi_netlink_init(void) } scsi_nl_sock = netlink_kernel_create(NETLINK_SCSITRANSPORT, - SCSI_NL_GRP_CNT, scsi_nl_rcv, THIS_MODULE); + SCSI_NL_GRP_CNT, scsi_nl_rcv, NULL, + THIS_MODULE); if (!scsi_nl_sock) { printk(KERN_ERR "%s: register of recieve handler failed\n", __FUNCTION__); diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index 10590cd7e9ed..aabaa0576ab4 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -1435,7 +1435,7 @@ static __init int iscsi_transport_init(void) if (err) goto unregister_conn_class; - nls = netlink_kernel_create(NETLINK_ISCSI, 1, iscsi_if_rx, + nls = netlink_kernel_create(NETLINK_ISCSI, 1, iscsi_if_rx, NULL, THIS_MODULE); if (!nls) { err = -ENOBUFS; diff --git a/fs/ecryptfs/netlink.c b/fs/ecryptfs/netlink.c index 8405d216a5fc..fe9186312d7c 100644 --- a/fs/ecryptfs/netlink.c +++ b/fs/ecryptfs/netlink.c @@ -229,7 +229,7 @@ int ecryptfs_init_netlink(void) ecryptfs_nl_sock = netlink_kernel_create(NETLINK_ECRYPTFS, 0, ecryptfs_receive_nl_message, - THIS_MODULE); + NULL, THIS_MODULE); if (!ecryptfs_nl_sock) { rc = -EIO; ecryptfs_printk(KERN_ERR, "Failed to create netlink socket\n"); diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 0d11f6a7389c..f41688f56632 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -157,7 +157,10 @@ struct netlink_skb_parms #define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds) -extern struct sock *netlink_kernel_create(int unit, unsigned int groups, void (*input)(struct sock *sk, int len), struct module *module); +extern struct sock *netlink_kernel_create(int unit, unsigned int groups, + void (*input)(struct sock *sk, int len), + struct mutex *cb_mutex, + struct module *module); extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err); extern int netlink_has_listeners(struct sock *sk, unsigned int group); extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock); diff --git a/kernel/audit.c b/kernel/audit.c index 80a7457dadbf..4e9d20829681 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -795,7 +795,7 @@ static int __init audit_init(void) printk(KERN_INFO "audit: initializing netlink socket (%s)\n", audit_default ? "enabled" : "disabled"); audit_sock = netlink_kernel_create(NETLINK_AUDIT, 0, audit_receive, - THIS_MODULE); + NULL, THIS_MODULE); if (!audit_sock) audit_panic("cannot initialize netlink socket"); else diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index 84272ed77f03..82fc1794b691 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -293,7 +293,7 @@ EXPORT_SYMBOL_GPL(add_uevent_var); static int __init kobject_uevent_init(void) { uevent_sock = netlink_kernel_create(NETLINK_KOBJECT_UEVENT, 1, NULL, - THIS_MODULE); + NULL, THIS_MODULE); if (!uevent_sock) { printk(KERN_ERR diff --git a/net/bridge/netfilter/ebt_ulog.c b/net/bridge/netfilter/ebt_ulog.c index 8b84cd40279e..9411db625917 100644 --- a/net/bridge/netfilter/ebt_ulog.c +++ b/net/bridge/netfilter/ebt_ulog.c @@ -302,7 +302,7 @@ static int __init ebt_ulog_init(void) } ebtulognl = netlink_kernel_create(NETLINK_NFLOG, EBT_ULOG_MAXNLGROUPS, - NULL, THIS_MODULE); + NULL, NULL, THIS_MODULE); if (!ebtulognl) ret = -ENOMEM; else if ((ret = ebt_register_watcher(&ulog))) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 5266df337051..648a7b6d15df 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -972,7 +972,7 @@ void __init rtnetlink_init(void) panic("rtnetlink_init: cannot allocate rta_buf\n"); rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv, - THIS_MODULE); + NULL, THIS_MODULE); if (rtnl == NULL) panic("rtnetlink_init: cannot initialize rtnetlink\n"); netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV); diff --git a/net/decnet/netfilter/dn_rtmsg.c b/net/decnet/netfilter/dn_rtmsg.c index 2ee47bab6938..696234688cf6 100644 --- a/net/decnet/netfilter/dn_rtmsg.c +++ b/net/decnet/netfilter/dn_rtmsg.c @@ -138,7 +138,7 @@ static int __init dn_rtmsg_init(void) int rv = 0; dnrmg = netlink_kernel_create(NETLINK_DNRTMSG, DNRNG_NLGRP_MAX, - dnrmg_receive_user_sk, THIS_MODULE); + dnrmg_receive_user_sk, NULL, THIS_MODULE); if (dnrmg == NULL) { printk(KERN_ERR "dn_rtmsg: Cannot create netlink socket"); return -ENOMEM; diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 5bf718a3e49b..953dd458c239 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -827,7 +827,8 @@ static void nl_fib_input(struct sock *sk, int len) static void nl_fib_lookup_init(void) { - netlink_kernel_create(NETLINK_FIB_LOOKUP, 0, nl_fib_input, THIS_MODULE); + netlink_kernel_create(NETLINK_FIB_LOOKUP, 0, nl_fib_input, NULL, + THIS_MODULE); } static void fib_disable_ip(struct net_device *dev, int force) diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index 0148f0e34ceb..dbeacd8b0f90 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -893,7 +893,7 @@ static int __init inet_diag_init(void) goto out; idiagnl = netlink_kernel_create(NETLINK_INET_DIAG, 0, inet_diag_rcv, - THIS_MODULE); + NULL, THIS_MODULE); if (idiagnl == NULL) goto out_free_table; err = 0; diff --git a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c index 0d72693869e6..702d94db19b9 100644 --- a/net/ipv4/netfilter/ip_queue.c +++ b/net/ipv4/netfilter/ip_queue.c @@ -668,7 +668,7 @@ static int __init ip_queue_init(void) netlink_register_notifier(&ipq_nl_notifier); ipqnl = netlink_kernel_create(NETLINK_FIREWALL, 0, ipq_rcv_sk, - THIS_MODULE); + NULL, THIS_MODULE); if (ipqnl == NULL) { printk(KERN_ERR "ip_queue: failed to create netlink socket\n"); goto cleanup_netlink_notifier; diff --git a/net/ipv4/netfilter/ipt_ULOG.c b/net/ipv4/netfilter/ipt_ULOG.c index a2bcba70af50..23b607b33b32 100644 --- a/net/ipv4/netfilter/ipt_ULOG.c +++ b/net/ipv4/netfilter/ipt_ULOG.c @@ -420,7 +420,7 @@ static int __init ipt_ulog_init(void) setup_timer(&ulog_buffers[i].timer, ulog_timer, i); nflognl = netlink_kernel_create(NETLINK_NFLOG, ULOG_MAXNLGROUPS, NULL, - THIS_MODULE); + NULL, THIS_MODULE); if (!nflognl) return -ENOMEM; diff --git a/net/ipv6/netfilter/ip6_queue.c b/net/ipv6/netfilter/ip6_queue.c index bfae9fdc4668..0004db38af6d 100644 --- a/net/ipv6/netfilter/ip6_queue.c +++ b/net/ipv6/netfilter/ip6_queue.c @@ -657,7 +657,7 @@ static int __init ip6_queue_init(void) struct proc_dir_entry *proc; netlink_register_notifier(&ipq_nl_notifier); - ipqnl = netlink_kernel_create(NETLINK_IP6_FW, 0, ipq_rcv_sk, + ipqnl = netlink_kernel_create(NETLINK_IP6_FW, 0, ipq_rcv_sk, NULL, THIS_MODULE); if (ipqnl == NULL) { printk(KERN_ERR "ip6_queue: failed to create netlink socket\n"); diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c index b0da853eabe0..8797e6953ef2 100644 --- a/net/netfilter/nfnetlink.c +++ b/net/netfilter/nfnetlink.c @@ -265,7 +265,7 @@ static int __init nfnetlink_init(void) printk("Netfilter messages via NETLINK v%s.\n", nfversion); nfnl = netlink_kernel_create(NETLINK_NETFILTER, NFNLGRP_MAX, - nfnetlink_rcv, THIS_MODULE); + nfnetlink_rcv, NULL, THIS_MODULE); if (!nfnl) { printk(KERN_ERR "cannot initialize nfnetlink!\n"); return -1; diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 2cbf1682f63d..ec16c9b7b3bd 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -56,6 +56,7 @@ #include #include #include +#include #include #include @@ -76,7 +77,8 @@ struct netlink_sock { unsigned long state; wait_queue_head_t wait; struct netlink_callback *cb; - spinlock_t cb_lock; + struct mutex *cb_mutex; + struct mutex cb_def_mutex; void (*data_ready)(struct sock *sk, int bytes); struct module *module; }; @@ -108,6 +110,7 @@ struct netlink_table { unsigned long *listeners; unsigned int nl_nonroot; unsigned int groups; + struct mutex *cb_mutex; struct module *module; int registered; }; @@ -370,7 +373,8 @@ static struct proto netlink_proto = { .obj_size = sizeof(struct netlink_sock), }; -static int __netlink_create(struct socket *sock, int protocol) +static int __netlink_create(struct socket *sock, struct mutex *cb_mutex, + int protocol) { struct sock *sk; struct netlink_sock *nlk; @@ -384,7 +388,8 @@ static int __netlink_create(struct socket *sock, int protocol) sock_init_data(sock, sk); nlk = nlk_sk(sk); - spin_lock_init(&nlk->cb_lock); + nlk->cb_mutex = cb_mutex ? : &nlk->cb_def_mutex; + mutex_init(nlk->cb_mutex); init_waitqueue_head(&nlk->wait); sk->sk_destruct = netlink_sock_destruct; @@ -395,6 +400,7 @@ static int __netlink_create(struct socket *sock, int protocol) static int netlink_create(struct socket *sock, int protocol) { struct module *module = NULL; + struct mutex *cb_mutex; struct netlink_sock *nlk; int err = 0; @@ -417,9 +423,10 @@ static int netlink_create(struct socket *sock, int protocol) if (nl_table[protocol].registered && try_module_get(nl_table[protocol].module)) module = nl_table[protocol].module; + cb_mutex = nl_table[protocol].cb_mutex; netlink_unlock_table(); - if ((err = __netlink_create(sock, protocol)) < 0) + if ((err = __netlink_create(sock, cb_mutex, protocol)) < 0) goto out_module; nlk = nlk_sk(sock->sk); @@ -444,14 +451,14 @@ static int netlink_release(struct socket *sock) sock_orphan(sk); nlk = nlk_sk(sk); - spin_lock(&nlk->cb_lock); + mutex_lock(nlk->cb_mutex); if (nlk->cb) { if (nlk->cb->done) nlk->cb->done(nlk->cb); netlink_destroy_callback(nlk->cb); nlk->cb = NULL; } - spin_unlock(&nlk->cb_lock); + mutex_unlock(nlk->cb_mutex); /* OK. Socket is unlinked, and, therefore, no new packets will arrive */ @@ -1266,7 +1273,7 @@ static void netlink_data_ready(struct sock *sk, int len) struct sock * netlink_kernel_create(int unit, unsigned int groups, void (*input)(struct sock *sk, int len), - struct module *module) + struct mutex *cb_mutex, struct module *module) { struct socket *sock; struct sock *sk; @@ -1281,7 +1288,7 @@ netlink_kernel_create(int unit, unsigned int groups, if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock)) return NULL; - if (__netlink_create(sock, unit) < 0) + if (__netlink_create(sock, cb_mutex, unit) < 0) goto out_sock_release; if (groups < 32) @@ -1305,6 +1312,7 @@ netlink_kernel_create(int unit, unsigned int groups, netlink_table_grab(); nl_table[unit].groups = groups; nl_table[unit].listeners = listeners; + nl_table[unit].cb_mutex = cb_mutex; nl_table[unit].module = module; nl_table[unit].registered = 1; netlink_table_ungrab(); @@ -1347,7 +1355,7 @@ static int netlink_dump(struct sock *sk) if (!skb) goto errout; - spin_lock(&nlk->cb_lock); + mutex_lock(nlk->cb_mutex); cb = nlk->cb; if (cb == NULL) { @@ -1358,7 +1366,7 @@ static int netlink_dump(struct sock *sk) len = cb->dump(skb, cb); if (len > 0) { - spin_unlock(&nlk->cb_lock); + mutex_unlock(nlk->cb_mutex); skb_queue_tail(&sk->sk_receive_queue, skb); sk->sk_data_ready(sk, len); return 0; @@ -1376,13 +1384,13 @@ static int netlink_dump(struct sock *sk) if (cb->done) cb->done(cb); nlk->cb = NULL; - spin_unlock(&nlk->cb_lock); + mutex_unlock(nlk->cb_mutex); netlink_destroy_callback(cb); return 0; errout_skb: - spin_unlock(&nlk->cb_lock); + mutex_unlock(nlk->cb_mutex); kfree_skb(skb); errout: return err; @@ -1414,15 +1422,15 @@ int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, } nlk = nlk_sk(sk); /* A dump or destruction is in progress... */ - spin_lock(&nlk->cb_lock); + mutex_lock(nlk->cb_mutex); if (nlk->cb || sock_flag(sk, SOCK_DEAD)) { - spin_unlock(&nlk->cb_lock); + mutex_unlock(nlk->cb_mutex); netlink_destroy_callback(cb); sock_put(sk); return -EBUSY; } nlk->cb = cb; - spin_unlock(&nlk->cb_lock); + mutex_unlock(nlk->cb_mutex); netlink_dump(sk); sock_put(sk); diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index fac2e7a6dbe4..6e31234a4196 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -558,7 +558,7 @@ static int __init genl_init(void) netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV); genl_sock = netlink_kernel_create(NETLINK_GENERIC, GENL_MAX_ID, - genl_rcv, THIS_MODULE); + genl_rcv, NULL, THIS_MODULE); if (genl_sock == NULL) panic("GENL: Cannot initialize generic netlink\n"); diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 2ff968373f1c..88659edc9b1a 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -2444,7 +2444,7 @@ static int __init xfrm_user_init(void) printk(KERN_INFO "Initializing XFRM netlink socket\n"); nlsk = netlink_kernel_create(NETLINK_XFRM, XFRMNLGRP_MAX, - xfrm_netlink_rcv, THIS_MODULE); + xfrm_netlink_rcv, NULL, THIS_MODULE); if (nlsk == NULL) return -ENOMEM; rcu_assign_pointer(xfrm_nl, nlsk); diff --git a/security/selinux/netlink.c b/security/selinux/netlink.c index 33f2e064a682..f49046de63a2 100644 --- a/security/selinux/netlink.c +++ b/security/selinux/netlink.c @@ -104,7 +104,7 @@ void selnl_notify_policyload(u32 seqno) static int __init selnl_init(void) { - selnl = netlink_kernel_create(NETLINK_SELINUX, SELNLGRP_MAX, NULL, + selnl = netlink_kernel_create(NETLINK_SELINUX, SELNLGRP_MAX, NULL, NULL, THIS_MODULE); if (selnl == NULL) panic("SELinux: Cannot create netlink socket."); -- 2.34.1