/* tunnel4.c: Generic IP tunnel transformer. * * Copyright (C) 2003 David S. Miller (davem@redhat.com) */ #include #include #include #include #include #include #include #include #include #include #include static struct xfrm_tunnel __rcu *tunnel4_handlers __read_mostly; static struct xfrm_tunnel __rcu *tunnel64_handlers __read_mostly; static struct xfrm_tunnel __rcu *tunnelmpls4_handlers __read_mostly; static DEFINE_MUTEX(tunnel4_mutex); static inline struct xfrm_tunnel __rcu **fam_handlers(unsigned short family) { return (family == AF_INET) ? &tunnel4_handlers : (family == AF_INET6) ? &tunnel64_handlers : &tunnelmpls4_handlers; } int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family) { struct xfrm_tunnel __rcu **pprev; struct xfrm_tunnel *t; int ret = -EEXIST; int priority = handler->priority; mutex_lock(&tunnel4_mutex); for (pprev = fam_handlers(family); (t = rcu_dereference_protected(*pprev, lockdep_is_held(&tunnel4_mutex))) != NULL; pprev = &t->next) { if (t->priority > priority) break; if (t->priority == priority) goto err; } handler->next = *pprev; rcu_assign_pointer(*pprev, handler); ret = 0; err: mutex_unlock(&tunnel4_mutex); return ret; } EXPORT_SYMBOL(xfrm4_tunnel_register); int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family) { struct xfrm_tunnel __rcu **pprev; struct xfrm_tunnel *t; int ret = -ENOENT; mutex_lock(&tunnel4_mutex); for (pprev = fam_handlers(family); (t = rcu_dereference_protected(*pprev, lockdep_is_held(&tunnel4_mutex))) != NULL; pprev = &t->next) { if (t == handler) { *pprev = handler->next; ret = 0; break; } } mutex_unlock(&tunnel4_mutex); synchronize_net(); return ret; } EXPORT_SYMBOL(xfrm4_tunnel_deregister); #define for_each_tunnel_rcu(head, handler) \ for (handler = rcu_dereference(head); \ handler != NULL; \ handler = rcu_dereference(handler->next)) \ static int tunnel4_rcv(struct sk_buff *skb) { struct xfrm_tunnel *handler; if (!pskb_may_pull(skb, sizeof(struct iphdr))) goto drop; for_each_tunnel_rcu(tunnel4_handlers, handler) if (!handler->handler(skb)) return 0; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); drop: kfree_skb(skb); return 0; } #if IS_ENABLED(CONFIG_IPV6) static int tunnel64_rcv(struct sk_buff *skb) { struct xfrm_tunnel *handler; if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) goto drop; for_each_tunnel_rcu(tunnel64_handlers, handler) if (!handler->handler(skb)) return 0; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); drop: kfree_skb(skb); return 0; } #endif #if IS_ENABLED(CONFIG_MPLS) static int tunnelmpls4_rcv(struct sk_buff *skb) { struct xfrm_tunnel *handler; if (!pskb_may_pull(skb, sizeof(struct mpls_label))) goto drop; for_each_tunnel_rcu(tunnelmpls4_handlers, handler) if (!handler->handler(skb)) return 0; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); drop: kfree_skb(skb); return 0; } #endif static void tunnel4_err(struct sk_buff *skb, u32 info) { struct xfrm_tunnel *handler; for_each_tunnel_rcu(tunnel4_handlers, handler) if (!handler->err_handler(skb, info)) break; } #if IS_ENABLED(CONFIG_IPV6) static void tunnel64_err(struct sk_buff *skb, u32 info) { struct xfrm_tunnel *handler; for_each_tunnel_rcu(tunnel64_handlers, handler) if (!handler->err_handler(skb, info)) break; } #endif #if IS_ENABLED(CONFIG_MPLS) static void tunnelmpls4_err(struct sk_buff *skb, u32 info) { struct xfrm_tunnel *handler; for_each_tunnel_rcu(tunnelmpls4_handlers, handler) if (!handler->err_handler(skb, info)) break; } #endif static const struct net_protocol tunnel4_protocol = { .handler = tunnel4_rcv, .err_handler = tunnel4_err, .no_policy = 1, .netns_ok = 1, }; #if IS_ENABLED(CONFIG_IPV6) static const struct net_protocol tunnel64_protocol = { .handler = tunnel64_rcv, .err_handler = tunnel64_err, .no_policy = 1, .netns_ok = 1, }; #endif #if IS_ENABLED(CONFIG_MPLS) static const struct net_protocol tunnelmpls4_protocol = { .handler = tunnelmpls4_rcv, .err_handler = tunnelmpls4_err, .no_policy = 1, .netns_ok = 1, }; #endif static int __init tunnel4_init(void) { if (inet_add_protocol(&tunnel4_protocol, IPPROTO_IPIP)) goto err; #if IS_ENABLED(CONFIG_IPV6) if (inet_add_protocol(&tunnel64_protocol, IPPROTO_IPV6)) { inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP); goto err; } #endif #if IS_ENABLED(CONFIG_MPLS) if (inet_add_protocol(&tunnelmpls4_protocol, IPPROTO_MPLS)) { inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP); #if IS_ENABLED(CONFIG_IPV6) inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6); #endif goto err; } #endif return 0; err: pr_err("%s: can't add protocol\n", __func__); return -EAGAIN; } static void __exit tunnel4_fini(void) { #if IS_ENABLED(CONFIG_MPLS) if (inet_del_protocol(&tunnelmpls4_protocol, IPPROTO_MPLS)) pr_err("tunnelmpls4 close: can't remove protocol\n"); #endif #if IS_ENABLED(CONFIG_IPV6) if (inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6)) pr_err("tunnel64 close: can't remove protocol\n"); #endif if (inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP)) pr_err("tunnel4 close: can't remove protocol\n"); } module_init(tunnel4_init); module_exit(tunnel4_fini); MODULE_LICENSE("GPL"); id'>28b08b519540041b06ed0ab0b1c005076b932e8e /net/irda/ircomm parent75422726b0f717d67db3283c2eb5bc14fa2619c5 (diff)
pid: fix lockdep deadlock warning due to ucount_lock
========================================================= [ INFO: possible irq lock inversion dependency detected ] 4.10.0-rc2-00024-g4aecec9-dirty #118 Tainted: G W --------------------------------------------------------- swapper/1/0 just changed the state of lock: (&(&sighand->siglock)->rlock){-.....}, at: [<ffffffffbd0a1bc6>] __lock_task_sighand+0xb6/0x2c0 but this lock took another, HARDIRQ-unsafe lock in the past: (ucounts_lock){+.+...} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Chain exists of: &(&sighand->siglock)->rlock --> &(&tty->ctrl_lock)->rlock --> ucounts_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(ucounts_lock); local_irq_disable(); lock(&(&sighand->siglock)->rlock); lock(&(&tty->ctrl_lock)->rlock); <Interrupt> lock(&(&sighand->siglock)->rlock); *** DEADLOCK *** This patch removes a dependency between rlock and ucount_lock. Fixes: f333c700c610 ("pidns: Add a limit on the number of pid namespaces") Cc: stable@vger.kernel.org Signed-off-by: Andrei Vagin <avagin@openvz.org> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Diffstat (limited to 'net/irda/ircomm')