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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/unix
downloadlinux-sh-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'net/unix')
-rw-r--r--net/unix/Makefile8
-rw-r--r--net/unix/af_unix.c2098
-rw-r--r--net/unix/garbage.c312
-rw-r--r--net/unix/sysctl_net_unix.c60
4 files changed, 2478 insertions, 0 deletions
diff --git a/net/unix/Makefile b/net/unix/Makefile
new file mode 100644
index 000000000000..b852a2bde9a8
--- /dev/null
+++ b/net/unix/Makefile
@@ -0,0 +1,8 @@
+#
+# Makefile for the Linux unix domain socket layer.
+#
+
+obj-$(CONFIG_UNIX) += unix.o
+
+unix-y := af_unix.o garbage.o
+unix-$(CONFIG_SYSCTL) += sysctl_net_unix.o
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
new file mode 100644
index 000000000000..acc73fe68698
--- /dev/null
+++ b/net/unix/af_unix.c
@@ -0,0 +1,2098 @@
+/*
+ * NET4: Implementation of BSD Unix domain sockets.
+ *
+ * Authors: Alan Cox, <alan.cox@linux.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Version: $Id: af_unix.c,v 1.133 2002/02/08 03:57:19 davem Exp $
+ *
+ * Fixes:
+ * Linus Torvalds : Assorted bug cures.
+ * Niibe Yutaka : async I/O support.
+ * Carsten Paeth : PF_UNIX check, address fixes.
+ * Alan Cox : Limit size of allocated blocks.
+ * Alan Cox : Fixed the stupid socketpair bug.
+ * Alan Cox : BSD compatibility fine tuning.
+ * Alan Cox : Fixed a bug in connect when interrupted.
+ * Alan Cox : Sorted out a proper draft version of
+ * file descriptor passing hacked up from
+ * Mike Shaver's work.
+ * Marty Leisner : Fixes to fd passing
+ * Nick Nevin : recvmsg bugfix.
+ * Alan Cox : Started proper garbage collector
+ * Heiko EiBfeldt : Missing verify_area check
+ * Alan Cox : Started POSIXisms
+ * Andreas Schwab : Replace inode by dentry for proper
+ * reference counting
+ * Kirk Petersen : Made this a module
+ * Christoph Rohland : Elegant non-blocking accept/connect algorithm.
+ * Lots of bug fixes.
+ * Alexey Kuznetosv : Repaired (I hope) bugs introduces
+ * by above two patches.
+ * Andrea Arcangeli : If possible we block in connect(2)
+ * if the max backlog of the listen socket
+ * is been reached. This won't break
+ * old apps and it will avoid huge amount
+ * of socks hashed (this for unix_gc()
+ * performances reasons).
+ * Security fix that limits the max
+ * number of socks to 2*max_files and
+ * the number of skb queueable in the
+ * dgram receiver.
+ * Artur Skawina : Hash function optimizations
+ * Alexey Kuznetsov : Full scale SMP. Lot of bugs are introduced 8)
+ * Malcolm Beattie : Set peercred for socketpair
+ * Michal Ostrowski : Module initialization cleanup.
+ * Arnaldo C. Melo : Remove MOD_{INC,DEC}_USE_COUNT,
+ * the core infrastructure is doing that
+ * for all net proto families now (2.5.69+)
+ *
+ *
+ * Known differences from reference BSD that was tested:
+ *
+ * [TO FIX]
+ * ECONNREFUSED is not returned from one end of a connected() socket to the
+ * other the moment one end closes.
+ * fstat() doesn't return st_dev=0, and give the blksize as high water mark
+ * and a fake inode identifier (nor the BSD first socket fstat twice bug).
+ * [NOT TO FIX]
+ * accept() returns a path name even if the connecting socket has closed
+ * in the meantime (BSD loses the path and gives up).
+ * accept() returns 0 length path for an unbound connector. BSD returns 16
+ * and a null first byte in the path (but not for gethost/peername - BSD bug ??)
+ * socketpair(...SOCK_RAW..) doesn't panic the kernel.
+ * BSD af_unix apparently has connect forgetting to block properly.
+ * (need to check this with the POSIX spec in detail)
+ *
+ * Differences from 2.0.0-11-... (ANK)
+ * Bug fixes and improvements.
+ * - client shutdown killed server socket.
+ * - removed all useless cli/sti pairs.
+ *
+ * Semantic changes/extensions.
+ * - generic control message passing.
+ * - SCM_CREDENTIALS control message.
+ * - "Abstract" (not FS based) socket bindings.
+ * Abstract names are sequences of bytes (not zero terminated)
+ * started by 0, so that this name space does not intersect
+ * with BSD names.
+ */
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/stat.h>
+#include <linux/dcache.h>
+#include <linux/namei.h>
+#include <linux/socket.h>
+#include <linux/un.h>
+#include <linux/fcntl.h>
+#include <linux/termios.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/in.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <asm/uaccess.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <net/sock.h>
+#include <linux/tcp.h>
+#include <net/af_unix.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <net/scm.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/smp_lock.h>
+#include <linux/rtnetlink.h>
+#include <linux/mount.h>
+#include <net/checksum.h>
+#include <linux/security.h>
+
+int sysctl_unix_max_dgram_qlen = 10;
+
+struct hlist_head unix_socket_table[UNIX_HASH_SIZE + 1];
+DEFINE_RWLOCK(unix_table_lock);
+static atomic_t unix_nr_socks = ATOMIC_INIT(0);
+
+#define unix_sockets_unbound (&unix_socket_table[UNIX_HASH_SIZE])
+
+#define UNIX_ABSTRACT(sk) (unix_sk(sk)->addr->hash != UNIX_HASH_SIZE)
+
+/*
+ * SMP locking strategy:
+ * hash table is protected with rwlock unix_table_lock
+ * each socket state is protected by separate rwlock.
+ */
+
+static inline unsigned unix_hash_fold(unsigned hash)
+{
+ hash ^= hash>>16;
+ hash ^= hash>>8;
+ return hash&(UNIX_HASH_SIZE-1);
+}
+
+#define unix_peer(sk) (unix_sk(sk)->peer)
+
+static inline int unix_our_peer(struct sock *sk, struct sock *osk)
+{
+ return unix_peer(osk) == sk;
+}
+
+static inline int unix_may_send(struct sock *sk, struct sock *osk)
+{
+ return (unix_peer(osk) == NULL || unix_our_peer(sk, osk));
+}
+
+static struct sock *unix_peer_get(struct sock *s)
+{
+ struct sock *peer;
+
+ unix_state_rlock(s);
+ peer = unix_peer(s);
+ if (peer)
+ sock_hold(peer);
+ unix_state_runlock(s);
+ return peer;
+}
+
+static inline void unix_release_addr(struct unix_address *addr)
+{
+ if (atomic_dec_and_test(&addr->refcnt))
+ kfree(addr);
+}
+
+/*
+ * Check unix socket name:
+ * - should be not zero length.
+ * - if started by not zero, should be NULL terminated (FS object)
+ * - if started by zero, it is abstract name.
+ */
+
+static int unix_mkname(struct sockaddr_un * sunaddr, int len, unsigned *hashp)
+{
+ if (len <= sizeof(short) || len > sizeof(*sunaddr))
+ return -EINVAL;
+ if (!sunaddr || sunaddr->sun_family != AF_UNIX)
+ return -EINVAL;
+ if (sunaddr->sun_path[0]) {
+ /*
+ * This may look like an off by one error but it is a bit more
+ * subtle. 108 is the longest valid AF_UNIX path for a binding.
+ * sun_path[108] doesnt as such exist. However in kernel space
+ * we are guaranteed that it is a valid memory location in our
+ * kernel address buffer.
+ */
+ ((char *)sunaddr)[len]=0;
+ len = strlen(sunaddr->sun_path)+1+sizeof(short);
+ return len;
+ }
+
+ *hashp = unix_hash_fold(csum_partial((char*)sunaddr, len, 0));
+ return len;
+}
+
+static void __unix_remove_socket(struct sock *sk)
+{
+ sk_del_node_init(sk);
+}
+
+static void __unix_insert_socket(struct hlist_head *list, struct sock *sk)
+{
+ BUG_TRAP(sk_unhashed(sk));
+ sk_add_node(sk, list);
+}
+
+static inline void unix_remove_socket(struct sock *sk)
+{
+ write_lock(&unix_table_lock);
+ __unix_remove_socket(sk);
+ write_unlock(&unix_table_lock);
+}
+
+static inline void unix_insert_socket(struct hlist_head *list, struct sock *sk)
+{
+ write_lock(&unix_table_lock);
+ __unix_insert_socket(list, sk);
+ write_unlock(&unix_table_lock);
+}
+
+static struct sock *__unix_find_socket_byname(struct sockaddr_un *sunname,
+ int len, int type, unsigned hash)
+{
+ struct sock *s;
+ struct hlist_node *node;
+
+ sk_for_each(s, node, &unix_socket_table[hash ^ type]) {
+ struct unix_sock *u = unix_sk(s);
+
+ if (u->addr->len == len &&
+ !memcmp(u->addr->name, sunname, len))
+ goto found;
+ }
+ s = NULL;
+found:
+ return s;
+}
+
+static inline struct sock *unix_find_socket_byname(struct sockaddr_un *sunname,
+ int len, int type,
+ unsigned hash)
+{
+ struct sock *s;
+
+ read_lock(&unix_table_lock);
+ s = __unix_find_socket_byname(sunname, len, type, hash);
+ if (s)
+ sock_hold(s);
+ read_unlock(&unix_table_lock);
+ return s;
+}
+
+static struct sock *unix_find_socket_byinode(struct inode *i)
+{
+ struct sock *s;
+ struct hlist_node *node;
+
+ read_lock(&unix_table_lock);
+ sk_for_each(s, node,
+ &unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) {
+ struct dentry *dentry = unix_sk(s)->dentry;
+
+ if(dentry && dentry->d_inode == i)
+ {
+ sock_hold(s);
+ goto found;
+ }
+ }
+ s = NULL;
+found:
+ read_unlock(&unix_table_lock);
+ return s;
+}
+
+static inline int unix_writable(struct sock *sk)
+{
+ return (atomic_read(&sk->sk_wmem_alloc) << 2) <= sk->sk_sndbuf;
+}
+
+static void unix_write_space(struct sock *sk)
+{
+ read_lock(&sk->sk_callback_lock);
+ if (unix_writable(sk)) {
+ if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
+ wake_up_interruptible(sk->sk_sleep);
+ sk_wake_async(sk, 2, POLL_OUT);
+ }
+ read_unlock(&sk->sk_callback_lock);
+}
+
+/* When dgram socket disconnects (or changes its peer), we clear its receive
+ * queue of packets arrived from previous peer. First, it allows to do
+ * flow control based only on wmem_alloc; second, sk connected to peer
+ * may receive messages only from that peer. */
+static void unix_dgram_disconnected(struct sock *sk, struct sock *other)
+{
+ if (skb_queue_len(&sk->sk_receive_queue)) {
+ skb_queue_purge(&sk->sk_receive_queue);
+ wake_up_interruptible_all(&unix_sk(sk)->peer_wait);
+
+ /* If one link of bidirectional dgram pipe is disconnected,
+ * we signal error. Messages are lost. Do not make this,
+ * when peer was not connected to us.
+ */
+ if (!sock_flag(other, SOCK_DEAD) && unix_peer(other) == sk) {
+ other->sk_err = ECONNRESET;
+ other->sk_error_report(other);
+ }
+ }
+}
+
+static void unix_sock_destructor(struct sock *sk)
+{
+ struct unix_sock *u = unix_sk(sk);
+
+ skb_queue_purge(&sk->sk_receive_queue);
+
+ BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
+ BUG_TRAP(sk_unhashed(sk));
+ BUG_TRAP(!sk->sk_socket);
+ if (!sock_flag(sk, SOCK_DEAD)) {
+ printk("Attempt to release alive unix socket: %p\n", sk);
+ return;
+ }
+
+ if (u->addr)
+ unix_release_addr(u->addr);
+
+ atomic_dec(&unix_nr_socks);
+#ifdef UNIX_REFCNT_DEBUG
+ printk(KERN_DEBUG "UNIX %p is destroyed, %d are still alive.\n", sk, atomic_read(&unix_nr_socks));
+#endif
+}
+
+static int unix_release_sock (struct sock *sk, int embrion)
+{
+ struct unix_sock *u = unix_sk(sk);
+ struct dentry *dentry;
+ struct vfsmount *mnt;
+ struct sock *skpair;
+ struct sk_buff *skb;
+ int state;
+
+ unix_remove_socket(sk);
+
+ /* Clear state */
+ unix_state_wlock(sk);
+ sock_orphan(sk);
+ sk->sk_shutdown = SHUTDOWN_MASK;
+ dentry = u->dentry;
+ u->dentry = NULL;
+ mnt = u->mnt;
+ u->mnt = NULL;
+ state = sk->sk_state;
+ sk->sk_state = TCP_CLOSE;
+ unix_state_wunlock(sk);
+
+ wake_up_interruptible_all(&u->peer_wait);
+
+ skpair=unix_peer(sk);
+
+ if (skpair!=NULL) {
+ if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) {
+ unix_state_wlock(skpair);
+ /* No more writes */
+ skpair->sk_shutdown = SHUTDOWN_MASK;
+ if (!skb_queue_empty(&sk->sk_receive_queue) || embrion)
+ skpair->sk_err = ECONNRESET;
+ unix_state_wunlock(skpair);
+ skpair->sk_state_change(skpair);
+ read_lock(&skpair->sk_callback_lock);
+ sk_wake_async(skpair,1,POLL_HUP);
+ read_unlock(&skpair->sk_callback_lock);
+ }
+ sock_put(skpair); /* It may now die */
+ unix_peer(sk) = NULL;
+ }
+
+ /* Try to flush out this socket. Throw out buffers at least */
+
+ while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+ if (state==TCP_LISTEN)
+ unix_release_sock(skb->sk, 1);
+ /* passed fds are erased in the kfree_skb hook */
+ kfree_skb(skb);
+ }
+
+ if (dentry) {
+ dput(dentry);
+ mntput(mnt);
+ }
+
+ sock_put(sk);
+
+ /* ---- Socket is dead now and most probably destroyed ---- */
+
+ /*
+ * Fixme: BSD difference: In BSD all sockets connected to use get
+ * ECONNRESET and we die on the spot. In Linux we behave
+ * like files and pipes do and wait for the last
+ * dereference.
+ *
+ * Can't we simply set sock->err?
+ *
+ * What the above comment does talk about? --ANK(980817)
+ */
+
+ if (atomic_read(&unix_tot_inflight))
+ unix_gc(); /* Garbage collect fds */
+
+ return 0;
+}
+
+static int unix_listen(struct socket *sock, int backlog)
+{
+ int err;
+ struct sock *sk = sock->sk;
+ struct unix_sock *u = unix_sk(sk);
+
+ err = -EOPNOTSUPP;
+ if (sock->type!=SOCK_STREAM && sock->type!=SOCK_SEQPACKET)
+ goto out; /* Only stream/seqpacket sockets accept */
+ err = -EINVAL;
+ if (!u->addr)
+ goto out; /* No listens on an unbound socket */
+ unix_state_wlock(sk);
+ if (sk->sk_state != TCP_CLOSE && sk->sk_state != TCP_LISTEN)
+ goto out_unlock;
+ if (backlog > sk->sk_max_ack_backlog)
+ wake_up_interruptible_all(&u->peer_wait);
+ sk->sk_max_ack_backlog = backlog;
+ sk->sk_state = TCP_LISTEN;
+ /* set credentials so connect can copy them */
+ sk->sk_peercred.pid = current->tgid;
+ sk->sk_peercred.uid = current->euid;
+ sk->sk_peercred.gid = current->egid;
+ err = 0;
+
+out_unlock:
+ unix_state_wunlock(sk);
+out:
+ return err;
+}
+
+static int unix_release(struct socket *);
+static int unix_bind(struct socket *, struct sockaddr *, int);
+static int unix_stream_connect(struct socket *, struct sockaddr *,
+ int addr_len, int flags);
+static int unix_socketpair(struct socket *, struct socket *);
+static int unix_accept(struct socket *, struct socket *, int);
+static int unix_getname(struct socket *, struct sockaddr *, int *, int);
+static unsigned int unix_poll(struct file *, struct socket *, poll_table *);
+static int unix_ioctl(struct socket *, unsigned int, unsigned long);
+static int unix_shutdown(struct socket *, int);
+static int unix_stream_sendmsg(struct kiocb *, struct socket *,
+ struct msghdr *, size_t);
+static int unix_stream_recvmsg(struct kiocb *, struct socket *,
+ struct msghdr *, size_t, int);
+static int unix_dgram_sendmsg(struct kiocb *, struct socket *,
+ struct msghdr *, size_t);
+static int unix_dgram_recvmsg(struct kiocb *, struct socket *,
+ struct msghdr *, size_t, int);
+static int unix_dgram_connect(struct socket *, struct sockaddr *,
+ int, int);
+static int unix_seqpacket_sendmsg(struct kiocb *, struct socket *,
+ struct msghdr *, size_t);
+
+static struct proto_ops unix_stream_ops = {
+ .family = PF_UNIX,
+ .owner = THIS_MODULE,
+ .release = unix_release,
+ .bind = unix_bind,
+ .connect = unix_stream_connect,
+ .socketpair = unix_socketpair,
+ .accept = unix_accept,
+ .getname = unix_getname,
+ .poll = unix_poll,
+ .ioctl = unix_ioctl,
+ .listen = unix_listen,
+ .shutdown = unix_shutdown,
+ .setsockopt = sock_no_setsockopt,
+ .getsockopt = sock_no_getsockopt,
+ .sendmsg = unix_stream_sendmsg,
+ .recvmsg = unix_stream_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static struct proto_ops unix_dgram_ops = {
+ .family = PF_UNIX,
+ .owner = THIS_MODULE,
+ .release = unix_release,
+ .bind = unix_bind,
+ .connect = unix_dgram_connect,
+ .socketpair = unix_socketpair,
+ .accept = sock_no_accept,
+ .getname = unix_getname,
+ .poll = datagram_poll,
+ .ioctl = unix_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = unix_shutdown,
+ .setsockopt = sock_no_setsockopt,
+ .getsockopt = sock_no_getsockopt,
+ .sendmsg = unix_dgram_sendmsg,
+ .recvmsg = unix_dgram_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static struct proto_ops unix_seqpacket_ops = {
+ .family = PF_UNIX,
+ .owner = THIS_MODULE,
+ .release = unix_release,
+ .bind = unix_bind,
+ .connect = unix_stream_connect,
+ .socketpair = unix_socketpair,
+ .accept = unix_accept,
+ .getname = unix_getname,
+ .poll = datagram_poll,
+ .ioctl = unix_ioctl,
+ .listen = unix_listen,
+ .shutdown = unix_shutdown,
+ .setsockopt = sock_no_setsockopt,
+ .getsockopt = sock_no_getsockopt,
+ .sendmsg = unix_seqpacket_sendmsg,
+ .recvmsg = unix_dgram_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static struct proto unix_proto = {
+ .name = "UNIX",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct unix_sock),
+};
+
+static struct sock * unix_create1(struct socket *sock)
+{
+ struct sock *sk = NULL;
+ struct unix_sock *u;
+
+ if (atomic_read(&unix_nr_socks) >= 2*files_stat.max_files)
+ goto out;
+
+ sk = sk_alloc(PF_UNIX, GFP_KERNEL, &unix_proto, 1);
+ if (!sk)
+ goto out;
+
+ atomic_inc(&unix_nr_socks);
+
+ sock_init_data(sock,sk);
+
+ sk->sk_write_space = unix_write_space;
+ sk->sk_max_ack_backlog = sysctl_unix_max_dgram_qlen;
+ sk->sk_destruct = unix_sock_destructor;
+ u = unix_sk(sk);
+ u->dentry = NULL;
+ u->mnt = NULL;
+ rwlock_init(&u->lock);
+ atomic_set(&u->inflight, sock ? 0 : -1);
+ init_MUTEX(&u->readsem); /* single task reading lock */
+ init_waitqueue_head(&u->peer_wait);
+ unix_insert_socket(unix_sockets_unbound, sk);
+out:
+ return sk;
+}
+
+static int unix_create(struct socket *sock, int protocol)
+{
+ if (protocol && protocol != PF_UNIX)
+ return -EPROTONOSUPPORT;
+
+ sock->state = SS_UNCONNECTED;
+
+ switch (sock->type) {
+ case SOCK_STREAM:
+ sock->ops = &unix_stream_ops;
+ break;
+ /*
+ * Believe it or not BSD has AF_UNIX, SOCK_RAW though
+ * nothing uses it.
+ */
+ case SOCK_RAW:
+ sock->type=SOCK_DGRAM;
+ case SOCK_DGRAM:
+ sock->ops = &unix_dgram_ops;
+ break;
+ case SOCK_SEQPACKET:
+ sock->ops = &unix_seqpacket_ops;
+ break;
+ default:
+ return -ESOCKTNOSUPPORT;
+ }
+
+ return unix_create1(sock) ? 0 : -ENOMEM;
+}
+
+static int unix_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+
+ if (!sk)
+ return 0;
+
+ sock->sk = NULL;
+
+ return unix_release_sock (sk, 0);
+}
+
+static int unix_autobind(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct unix_sock *u = unix_sk(sk);
+ static u32 ordernum = 1;
+ struct unix_address * addr;
+ int err;
+
+ down(&u->readsem);
+
+ err = 0;
+ if (u->addr)
+ goto out;
+
+ err = -ENOMEM;
+ addr = kmalloc(sizeof(*addr) + sizeof(short) + 16, GFP_KERNEL);
+ if (!addr)
+ goto out;
+
+ memset(addr, 0, sizeof(*addr) + sizeof(short) + 16);
+ addr->name->sun_family = AF_UNIX;
+ atomic_set(&addr->refcnt, 1);
+
+retry:
+ addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + sizeof(short);
+ addr->hash = unix_hash_fold(csum_partial((void*)addr->name, addr->len, 0));
+
+ write_lock(&unix_table_lock);
+ ordernum = (ordernum+1)&0xFFFFF;
+
+ if (__unix_find_socket_byname(addr->name, addr->len, sock->type,
+ addr->hash)) {
+ write_unlock(&unix_table_lock);
+ /* Sanity yield. It is unusual case, but yet... */
+ if (!(ordernum&0xFF))
+ yield();
+ goto retry;
+ }
+ addr->hash ^= sk->sk_type;
+
+ __unix_remove_socket(sk);
+ u->addr = addr;
+ __unix_insert_socket(&unix_socket_table[addr->hash], sk);
+ write_unlock(&unix_table_lock);
+ err = 0;
+
+out: up(&u->readsem);
+ return err;
+}
+
+static struct sock *unix_find_other(struct sockaddr_un *sunname, int len,
+ int type, unsigned hash, int *error)
+{
+ struct sock *u;
+ struct nameidata nd;
+ int err = 0;
+
+ if (sunname->sun_path[0]) {
+ err = path_lookup(sunname->sun_path, LOOKUP_FOLLOW, &nd);
+ if (err)
+ goto fail;
+ err = permission(nd.dentry->d_inode,MAY_WRITE, &nd);
+ if (err)
+ goto put_fail;
+
+ err = -ECONNREFUSED;
+ if (!S_ISSOCK(nd.dentry->d_inode->i_mode))
+ goto put_fail;
+ u=unix_find_socket_byinode(nd.dentry->d_inode);
+ if (!u)
+ goto put_fail;
+
+ if (u->sk_type == type)
+ touch_atime(nd.mnt, nd.dentry);
+
+ path_release(&nd);
+
+ err=-EPROTOTYPE;
+ if (u->sk_type != type) {
+ sock_put(u);
+ goto fail;
+ }
+ } else {
+ err = -ECONNREFUSED;
+ u=unix_find_socket_byname(sunname, len, type, hash);
+ if (u) {
+ struct dentry *dentry;
+ dentry = unix_sk(u)->dentry;
+ if (dentry)
+ touch_atime(unix_sk(u)->mnt, dentry);
+ } else
+ goto fail;
+ }
+ return u;
+
+put_fail:
+ path_release(&nd);
+fail:
+ *error=err;
+ return NULL;
+}
+
+
+static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
+{
+ struct sock *sk = sock->sk;
+ struct unix_sock *u = unix_sk(sk);
+ struct sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr;
+ struct dentry * dentry = NULL;
+ struct nameidata nd;
+ int err;
+ unsigned hash;
+ struct unix_address *addr;
+ struct hlist_head *list;
+
+ err = -EINVAL;
+ if (sunaddr->sun_family != AF_UNIX)
+ goto out;
+
+ if (addr_len==sizeof(short)) {
+ err = unix_autobind(sock);
+ goto out;
+ }
+
+ err = unix_mkname(sunaddr, addr_len, &hash);
+ if (err < 0)
+ goto out;
+ addr_len = err;
+
+ down(&u->readsem);
+
+ err = -EINVAL;
+ if (u->addr)
+ goto out_up;
+
+ err = -ENOMEM;
+ addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL);
+ if (!addr)
+ goto out_up;
+
+ memcpy(addr->name, sunaddr, addr_len);
+ addr->len = addr_len;
+ addr->hash = hash ^ sk->sk_type;
+ atomic_set(&addr->refcnt, 1);
+
+ if (sunaddr->sun_path[0]) {
+ unsigned int mode;
+ err = 0;
+ /*
+ * Get the parent directory, calculate the hash for last
+ * component.
+ */
+ err = path_lookup(sunaddr->sun_path, LOOKUP_PARENT, &nd);
+ if (err)
+ goto out_mknod_parent;
+ /*
+ * Yucky last component or no last component at all?
+ * (foo/., foo/.., /////)
+ */
+ err = -EEXIST;
+ if (nd.last_type != LAST_NORM)
+ goto out_mknod;
+ /*
+ * Lock the directory.
+ */
+ down(&nd.dentry->d_inode->i_sem);
+ /*
+ * Do the final lookup.
+ */
+ dentry = lookup_hash(&nd.last, nd.dentry);
+ err = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ goto out_mknod_unlock;
+ err = -ENOENT;
+ /*
+ * Special case - lookup gave negative, but... we had foo/bar/
+ * From the vfs_mknod() POV we just have a negative dentry -
+ * all is fine. Let's be bastards - you had / on the end, you've
+ * been asking for (non-existent) directory. -ENOENT for you.
+ */
+ if (nd.last.name[nd.last.len] && !dentry->d_inode)
+ goto out_mknod_dput;
+ /*
+ * All right, let's create it.
+ */
+ mode = S_IFSOCK |
+ (SOCK_INODE(sock)->i_mode & ~current->fs->umask);
+ err = vfs_mknod(nd.dentry->d_inode, dentry, mode, 0);
+ if (err)
+ goto out_mknod_dput;
+ up(&nd.dentry->d_inode->i_sem);
+ dput(nd.dentry);
+ nd.dentry = dentry;
+
+ addr->hash = UNIX_HASH_SIZE;
+ }
+
+ write_lock(&unix_table_lock);
+
+ if (!sunaddr->sun_path[0]) {
+ err = -EADDRINUSE;
+ if (__unix_find_socket_byname(sunaddr, addr_len,
+ sk->sk_type, hash)) {
+ unix_release_addr(addr);
+ goto out_unlock;
+ }
+
+ list = &unix_socket_table[addr->hash];
+ } else {
+ list = &unix_socket_table[dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1)];
+ u->dentry = nd.dentry;
+ u->mnt = nd.mnt;
+ }
+
+ err = 0;
+ __unix_remove_socket(sk);
+ u->addr = addr;
+ __unix_insert_socket(list, sk);
+
+out_unlock:
+ write_unlock(&unix_table_lock);
+out_up:
+ up(&u->readsem);
+out:
+ return err;
+
+out_mknod_dput:
+ dput(dentry);
+out_mknod_unlock:
+ up(&nd.dentry->d_inode->i_sem);
+out_mknod:
+ path_release(&nd);
+out_mknod_parent:
+ if (err==-EEXIST)
+ err=-EADDRINUSE;
+ unix_release_addr(addr);
+ goto out_up;
+}
+
+static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr,
+ int alen, int flags)
+{
+ struct sock *sk = sock->sk;
+ struct sockaddr_un *sunaddr=(struct sockaddr_un*)addr;
+ struct sock *other;
+ unsigned hash;
+ int err;
+
+ if (addr->sa_family != AF_UNSPEC) {
+ err = unix_mkname(sunaddr, alen, &hash);
+ if (err < 0)
+ goto out;
+ alen = err;
+
+ if (test_bit(SOCK_PASSCRED, &sock->flags) &&
+ !unix_sk(sk)->addr && (err = unix_autobind(sock)) != 0)
+ goto out;
+
+ other=unix_find_other(sunaddr, alen, sock->type, hash, &err);
+ if (!other)
+ goto out;
+
+ unix_state_wlock(sk);
+
+ err = -EPERM;
+ if (!unix_may_send(sk, other))
+ goto out_unlock;
+
+ err = security_unix_may_send(sk->sk_socket, other->sk_socket);
+ if (err)
+ goto out_unlock;
+
+ } else {
+ /*
+ * 1003.1g breaking connected state with AF_UNSPEC
+ */
+ other = NULL;
+ unix_state_wlock(sk);
+ }
+
+ /*
+ * If it was connected, reconnect.
+ */
+ if (unix_peer(sk)) {
+ struct sock *old_peer = unix_peer(sk);
+ unix_peer(sk)=other;
+ unix_state_wunlock(sk);
+
+ if (other != old_peer)
+ unix_dgram_disconnected(sk, old_peer);
+ sock_put(old_peer);
+ } else {
+ unix_peer(sk)=other;
+ unix_state_wunlock(sk);
+ }
+ return 0;
+
+out_unlock:
+ unix_state_wunlock(sk);
+ sock_put(other);
+out:
+ return err;
+}
+
+static long unix_wait_for_peer(struct sock *other, long timeo)
+{
+ struct unix_sock *u = unix_sk(other);
+ int sched;
+ DEFINE_WAIT(wait);
+
+ prepare_to_wait_exclusive(&u->peer_wait, &wait, TASK_INTERRUPTIBLE);
+
+ sched = !sock_flag(other, SOCK_DEAD) &&
+ !(other->sk_shutdown & RCV_SHUTDOWN) &&
+ (skb_queue_len(&other->sk_receive_queue) >
+ other->sk_max_ack_backlog);
+
+ unix_state_runlock(other);
+
+ if (sched)
+ timeo = schedule_timeout(timeo);
+
+ finish_wait(&u->peer_wait, &wait);
+ return timeo;
+}
+
+static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
+ int addr_len, int flags)
+{
+ struct sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr;
+ struct sock *sk = sock->sk;
+ struct unix_sock *u = unix_sk(sk), *newu, *otheru;
+ struct sock *newsk = NULL;
+ struct sock *other = NULL;
+ struct sk_buff *skb = NULL;
+ unsigned hash;
+ int st;
+ int err;
+ long timeo;
+
+ err = unix_mkname(sunaddr, addr_len, &hash);
+ if (err < 0)
+ goto out;
+ addr_len = err;
+
+ if (test_bit(SOCK_PASSCRED, &sock->flags)
+ && !u->addr && (err = unix_autobind(sock)) != 0)
+ goto out;
+
+ timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
+
+ /* First of all allocate resources.
+ If we will make it after state is locked,
+ we will have to recheck all again in any case.
+ */
+
+ err = -ENOMEM;
+
+ /* create new sock for complete connection */
+ newsk = unix_create1(NULL);
+ if (newsk == NULL)
+ goto out;
+
+ /* Allocate skb for sending to listening sock */
+ skb = sock_wmalloc(newsk, 1, 0, GFP_KERNEL);
+ if (skb == NULL)
+ goto out;
+
+restart:
+ /* Find listening sock. */
+ other = unix_find_other(sunaddr, addr_len, sk->sk_type, hash, &err);
+ if (!other)
+ goto out;
+
+ /* Latch state of peer */
+ unix_state_rlock(other);
+
+ /* Apparently VFS overslept socket death. Retry. */
+ if (sock_flag(other, SOCK_DEAD)) {
+ unix_state_runlock(other);
+ sock_put(other);
+ goto restart;
+ }
+
+ err = -ECONNREFUSED;
+ if (other->sk_state != TCP_LISTEN)
+ goto out_unlock;
+
+ if (skb_queue_len(&other->sk_receive_queue) >
+ other->sk_max_ack_backlog) {
+ err = -EAGAIN;
+ if (!timeo)
+ goto out_unlock;
+
+ timeo = unix_wait_for_peer(other, timeo);
+
+ err = sock_intr_errno(timeo);
+ if (signal_pending(current))
+ goto out;
+ sock_put(other);
+ goto restart;
+ }
+
+ /* Latch our state.
+
+ It is tricky place. We need to grab write lock and cannot
+ drop lock on peer. It is dangerous because deadlock is
+ possible. Connect to self case and simultaneous
+ attempt to connect are eliminated by checking socket
+ state. other is TCP_LISTEN, if sk is TCP_LISTEN we
+ check this before attempt to grab lock.
+
+ Well, and we have to recheck the state after socket locked.
+ */
+ st = sk->sk_state;
+
+ switch (st) {
+ case TCP_CLOSE:
+ /* This is ok... continue with connect */
+ break;
+ case TCP_ESTABLISHED:
+ /* Socket is already connected */
+ err = -EISCONN;
+ goto out_unlock;
+ default:
+ err = -EINVAL;
+ goto out_unlock;
+ }
+
+ unix_state_wlock(sk);
+
+ if (sk->sk_state != st) {
+ unix_state_wunlock(sk);
+ unix_state_runlock(other);
+ sock_put(other);
+ goto restart;
+ }
+
+ err = security_unix_stream_connect(sock, other->sk_socket, newsk);
+ if (err) {
+ unix_state_wunlock(sk);
+ goto out_unlock;
+ }
+
+ /* The way is open! Fastly set all the necessary fields... */
+
+ sock_hold(sk);
+ unix_peer(newsk) = sk;
+ newsk->sk_state = TCP_ESTABLISHED;
+ newsk->sk_type = sk->sk_type;
+ newsk->sk_peercred.pid = current->tgid;
+ newsk->sk_peercred.uid = current->euid;
+ newsk->sk_peercred.gid = current->egid;
+ newu = unix_sk(newsk);
+ newsk->sk_sleep = &newu->peer_wait;
+ otheru = unix_sk(other);
+
+ /* copy address information from listening to new sock*/
+ if (otheru->addr) {
+ atomic_inc(&otheru->addr->refcnt);
+ newu->addr = otheru->addr;
+ }
+ if (otheru->dentry) {
+ newu->dentry = dget(otheru->dentry);
+ newu->mnt = mntget(otheru->mnt);
+ }
+
+ /* Set credentials */
+ sk->sk_peercred = other->sk_peercred;
+
+ sock_hold(newsk);
+ unix_peer(sk) = newsk;
+ sock->state = SS_CONNECTED;
+ sk->sk_state = TCP_ESTABLISHED;
+
+ unix_state_wunlock(sk);
+
+ /* take ten and and send info to listening sock */
+ spin_lock(&other->sk_receive_queue.lock);
+ __skb_queue_tail(&other->sk_receive_queue, skb);
+ /* Undo artificially decreased inflight after embrion
+ * is installed to listening socket. */
+ atomic_inc(&newu->inflight);
+ spin_unlock(&other->sk_receive_queue.lock);
+ unix_state_runlock(other);
+ other->sk_data_ready(other, 0);
+ sock_put(other);
+ return 0;
+
+out_unlock:
+ if (other)
+ unix_state_runlock(other);
+
+out:
+ if (skb)
+ kfree_skb(skb);
+ if (newsk)
+ unix_release_sock(newsk, 0);
+ if (other)
+ sock_put(other);
+ return err;
+}
+
+static int unix_socketpair(struct socket *socka, struct socket *sockb)
+{
+ struct sock *ska=socka->sk, *skb = sockb->sk;
+
+ /* Join our sockets back to back */
+ sock_hold(ska);
+ sock_hold(skb);
+ unix_peer(ska)=skb;
+ unix_peer(skb)=ska;
+ ska->sk_peercred.pid = skb->sk_peercred.pid = current->tgid;
+ ska->sk_peercred.uid = skb->sk_peercred.uid = current->euid;
+ ska->sk_peercred.gid = skb->sk_peercred.gid = current->egid;
+
+ if (ska->sk_type != SOCK_DGRAM) {
+ ska->sk_state = TCP_ESTABLISHED;
+ skb->sk_state = TCP_ESTABLISHED;
+ socka->state = SS_CONNECTED;
+ sockb->state = SS_CONNECTED;
+ }
+ return 0;
+}
+
+static int unix_accept(struct socket *sock, struct socket *newsock, int flags)
+{
+ struct sock *sk = sock->sk;
+ struct sock *tsk;
+ struct sk_buff *skb;
+ int err;
+
+ err = -EOPNOTSUPP;
+ if (sock->type!=SOCK_STREAM && sock->type!=SOCK_SEQPACKET)
+ goto out;
+
+ err = -EINVAL;
+ if (sk->sk_state != TCP_LISTEN)
+ goto out;
+
+ /* If socket state is TCP_LISTEN it cannot change (for now...),
+ * so that no locks are necessary.
+ */
+
+ skb = skb_recv_datagram(sk, 0, flags&O_NONBLOCK, &err);
+ if (!skb) {
+ /* This means receive shutdown. */
+ if (err == 0)
+ err = -EINVAL;
+ goto out;
+ }
+
+ tsk = skb->sk;
+ skb_free_datagram(sk, skb);
+ wake_up_interruptible(&unix_sk(sk)->peer_wait);
+
+ /* attach accepted sock to socket */
+ unix_state_wlock(tsk);
+ newsock->state = SS_CONNECTED;
+ sock_graft(tsk, newsock);
+ unix_state_wunlock(tsk);
+ return 0;
+
+out:
+ return err;
+}
+
+
+static int unix_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len, int peer)
+{
+ struct sock *sk = sock->sk;
+ struct unix_sock *u;
+ struct sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr;
+ int err = 0;
+
+ if (peer) {
+ sk = unix_peer_get(sk);
+
+ err = -ENOTCONN;
+ if (!sk)
+ goto out;
+ err = 0;
+ } else {
+ sock_hold(sk);
+ }
+
+ u = unix_sk(sk);
+ unix_state_rlock(sk);
+ if (!u->addr) {
+ sunaddr->sun_family = AF_UNIX;
+ sunaddr->sun_path[0] = 0;
+ *uaddr_len = sizeof(short);
+ } else {
+ struct unix_address *addr = u->addr;
+
+ *uaddr_len = addr->len;
+ memcpy(sunaddr, addr->name, *uaddr_len);
+ }
+ unix_state_runlock(sk);
+ sock_put(sk);
+out:
+ return err;
+}
+
+static void unix_detach_fds(struct scm_cookie *scm, struct sk_buff *skb)
+{
+ int i;
+
+ scm->fp = UNIXCB(skb).fp;
+ skb->destructor = sock_wfree;
+ UNIXCB(skb).fp = NULL;
+
+ for (i=scm->fp->count-1; i>=0; i--)
+ unix_notinflight(scm->fp->fp[i]);
+}
+
+static void unix_destruct_fds(struct sk_buff *skb)
+{
+ struct scm_cookie scm;
+ memset(&scm, 0, sizeof(scm));
+ unix_detach_fds(&scm, skb);
+
+ /* Alas, it calls VFS */
+ /* So fscking what? fput() had been SMP-safe since the last Summer */
+ scm_destroy(&scm);
+ sock_wfree(skb);
+}
+
+static void unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb)
+{
+ int i;
+ for (i=scm->fp->count-1; i>=0; i--)
+ unix_inflight(scm->fp->fp[i]);
+ UNIXCB(skb).fp = scm->fp;
+ skb->destructor = unix_destruct_fds;
+ scm->fp = NULL;
+}
+
+/*
+ * Send AF_UNIX data.
+ */
+
+static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock,
+ struct msghdr *msg, size_t len)
+{
+ struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
+ struct sock *sk = sock->sk;
+ struct unix_sock *u = unix_sk(sk);
+ struct sockaddr_un *sunaddr=msg->msg_name;
+ struct sock *other = NULL;
+ int namelen = 0; /* fake GCC */
+ int err;
+ unsigned hash;
+ struct sk_buff *skb;
+ long timeo;
+ struct scm_cookie tmp_scm;
+
+ if (NULL == siocb->scm)
+ siocb->scm = &tmp_scm;
+ err = scm_send(sock, msg, siocb->scm);
+ if (err < 0)
+ return err;
+
+ err = -EOPNOTSUPP;
+ if (msg->msg_flags&MSG_OOB)
+ goto out;
+
+ if (msg->msg_namelen) {
+ err = unix_mkname(sunaddr, msg->msg_namelen, &hash);
+ if (err < 0)
+ goto out;
+ namelen = err;
+ } else {
+ sunaddr = NULL;
+ err = -ENOTCONN;
+ other = unix_peer_get(sk);
+ if (!other)
+ goto out;
+ }
+
+ if (test_bit(SOCK_PASSCRED, &sock->flags)
+ && !u->addr && (err = unix_autobind(sock)) != 0)
+ goto out;
+
+ err = -EMSGSIZE;
+ if (len > sk->sk_sndbuf - 32)
+ goto out;
+
+ skb = sock_alloc_send_skb(sk, len, msg->msg_flags&MSG_DONTWAIT, &err);
+ if (skb==NULL)
+ goto out;
+
+ memcpy(UNIXCREDS(skb), &siocb->scm->creds, sizeof(struct ucred));
+ if (siocb->scm->fp)
+ unix_attach_fds(siocb->scm, skb);
+
+ skb->h.raw = skb->data;
+ err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
+ if (err)
+ goto out_free;
+
+ timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
+
+restart:
+ if (!other) {
+ err = -ECONNRESET;
+ if (sunaddr == NULL)
+ goto out_free;
+
+ other = unix_find_other(sunaddr, namelen, sk->sk_type,
+ hash, &err);
+ if (other==NULL)
+ goto out_free;
+ }
+
+ unix_state_rlock(other);
+ err = -EPERM;
+ if (!unix_may_send(sk, other))
+ goto out_unlock;
+
+ if (sock_flag(other, SOCK_DEAD)) {
+ /*
+ * Check with 1003.1g - what should
+ * datagram error
+ */
+ unix_state_runlock(other);
+ sock_put(other);
+
+ err = 0;
+ unix_state_wlock(sk);
+ if (unix_peer(sk) == other) {
+ unix_peer(sk)=NULL;
+ unix_state_wunlock(sk);
+
+ unix_dgram_disconnected(sk, other);
+ sock_put(other);
+ err = -ECONNREFUSED;
+ } else {
+ unix_state_wunlock(sk);
+ }
+
+ other = NULL;
+ if (err)
+ goto out_free;
+ goto restart;
+ }
+
+ err = -EPIPE;
+ if (other->sk_shutdown & RCV_SHUTDOWN)
+ goto out_unlock;
+
+ if (sk->sk_type != SOCK_SEQPACKET) {
+ err = security_unix_may_send(sk->sk_socket, other->sk_socket);
+ if (err)
+ goto out_unlock;
+ }
+
+ if (unix_peer(other) != sk &&
+ (skb_queue_len(&other->sk_receive_queue) >
+ other->sk_max_ack_backlog)) {
+ if (!timeo) {
+ err = -EAGAIN;
+ goto out_unlock;
+ }
+
+ timeo = unix_wait_for_peer(other, timeo);
+
+ err = sock_intr_errno(timeo);
+ if (signal_pending(current))
+ goto out_free;
+
+ goto restart;
+ }
+
+ skb_queue_tail(&other->sk_receive_queue, skb);
+ unix_state_runlock(other);
+ other->sk_data_ready(other, len);
+ sock_put(other);
+ scm_destroy(siocb->scm);
+ return len;
+
+out_unlock:
+ unix_state_runlock(other);
+out_free:
+ kfree_skb(skb);
+out:
+ if (other)
+ sock_put(other);
+ scm_destroy(siocb->scm);
+ return err;
+}
+
+
+static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
+ struct msghdr *msg, size_t len)
+{
+ struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
+ struct sock *sk = sock->sk;
+ struct sock *other = NULL;
+ struct sockaddr_un *sunaddr=msg->msg_name;
+ int err,size;
+ struct sk_buff *skb;
+ int sent=0;
+ struct scm_cookie tmp_scm;
+
+ if (NULL == siocb->scm)
+ siocb->scm = &tmp_scm;
+ err = scm_send(sock, msg, siocb->scm);
+ if (err < 0)
+ return err;
+
+ err = -EOPNOTSUPP;
+ if (msg->msg_flags&MSG_OOB)
+ goto out_err;
+
+ if (msg->msg_namelen) {
+ err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
+ goto out_err;
+ } else {
+ sunaddr = NULL;
+ err = -ENOTCONN;
+ other = unix_peer_get(sk);
+ if (!other)
+ goto out_err;
+ }
+
+ if (sk->sk_shutdown & SEND_SHUTDOWN)
+ goto pipe_err;
+
+ while(sent < len)
+ {
+ /*
+ * Optimisation for the fact that under 0.01% of X messages typically
+ * need breaking up.
+ */
+
+ size=len-sent;
+
+ /* Keep two messages in the pipe so it schedules better */
+ if (size > sk->sk_sndbuf / 2 - 64)
+ size = sk->sk_sndbuf / 2 - 64;
+
+ if (size > SKB_MAX_ALLOC)
+ size = SKB_MAX_ALLOC;
+
+ /*
+ * Grab a buffer
+ */
+
+ skb=sock_alloc_send_skb(sk,size,msg->msg_flags&MSG_DONTWAIT, &err);
+
+ if (skb==NULL)
+ goto out_err;
+
+ /*
+ * If you pass two values to the sock_alloc_send_skb
+ * it tries to grab the large buffer with GFP_NOFS
+ * (which can fail easily), and if it fails grab the
+ * fallback size buffer which is under a page and will
+ * succeed. [Alan]
+ */
+ size = min_t(int, size, skb_tailroom(skb));
+
+ memcpy(UNIXCREDS(skb), &siocb->scm->creds, sizeof(struct ucred));
+ if (siocb->scm->fp)
+ unix_attach_fds(siocb->scm, skb);
+
+ if ((err = memcpy_fromiovec(skb_put(skb,size), msg->msg_iov, size)) != 0) {
+ kfree_skb(skb);
+ goto out_err;
+ }
+
+ unix_state_rlock(other);
+
+ if (sock_flag(other, SOCK_DEAD) ||
+ (other->sk_shutdown & RCV_SHUTDOWN))
+ goto pipe_err_free;
+
+ skb_queue_tail(&other->sk_receive_queue, skb);
+ unix_state_runlock(other);
+ other->sk_data_ready(other, size);
+ sent+=size;
+ }
+ sock_put(other);
+
+ scm_destroy(siocb->scm);
+ siocb->scm = NULL;
+
+ return sent;
+
+pipe_err_free:
+ unix_state_runlock(other);
+ kfree_skb(skb);
+pipe_err:
+ if (sent==0 && !(msg->msg_flags&MSG_NOSIGNAL))
+ send_sig(SIGPIPE,current,0);
+ err = -EPIPE;
+out_err:
+ if (other)
+ sock_put(other);
+ scm_destroy(siocb->scm);
+ siocb->scm = NULL;
+ return sent ? : err;
+}
+
+static int unix_seqpacket_sendmsg(struct kiocb *kiocb, struct socket *sock,
+ struct msghdr *msg, size_t len)
+{
+ int err;
+ struct sock *sk = sock->sk;
+
+ err = sock_error(sk);
+ if (err)
+ return err;
+
+ if (sk->sk_state != TCP_ESTABLISHED)
+ return -ENOTCONN;
+
+ if (msg->msg_namelen)
+ msg->msg_namelen = 0;
+
+ return unix_dgram_sendmsg(kiocb, sock, msg, len);
+}
+
+static void unix_copy_addr(struct msghdr *msg, struct sock *sk)
+{
+ struct unix_sock *u = unix_sk(sk);
+
+ msg->msg_namelen = 0;
+ if (u->addr) {
+ msg->msg_namelen = u->addr->len;
+ memcpy(msg->msg_name, u->addr->name, u->addr->len);
+ }
+}
+
+static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock,
+ struct msghdr *msg, size_t size,
+ int flags)
+{
+ struct sock_iocb *siocb = kiocb_to_siocb(iocb);
+ struct scm_cookie tmp_scm;
+ struct sock *sk = sock->sk;
+ struct unix_sock *u = unix_sk(sk);
+ int noblock = flags & MSG_DONTWAIT;
+ struct sk_buff *skb;
+ int err;
+
+ err = -EOPNOTSUPP;
+ if (flags&MSG_OOB)
+ goto out;
+
+ msg->msg_namelen = 0;
+
+ down(&u->readsem);
+
+ skb = skb_recv_datagram(sk, flags, noblock, &err);
+ if (!skb)
+ goto out_unlock;
+
+ wake_up_interruptible(&u->peer_wait);
+
+ if (msg->msg_name)
+ unix_copy_addr(msg, skb->sk);
+
+ if (size > skb->len)
+ size = skb->len;
+ else if (size < skb->len)
+ msg->msg_flags |= MSG_TRUNC;
+
+ err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, size);
+ if (err)
+ goto out_free;
+
+ if (!siocb->scm) {
+ siocb->scm = &tmp_scm;
+ memset(&tmp_scm, 0, sizeof(tmp_scm));
+ }
+ siocb->scm->creds = *UNIXCREDS(skb);
+
+ if (!(flags & MSG_PEEK))
+ {
+ if (UNIXCB(skb).fp)
+ unix_detach_fds(siocb->scm, skb);
+ }
+ else
+ {
+ /* It is questionable: on PEEK we could:
+ - do not return fds - good, but too simple 8)
+ - return fds, and do not return them on read (old strategy,
+ apparently wrong)
+ - clone fds (I chose it for now, it is the most universal
+ solution)
+
+ POSIX 1003.1g does not actually define this clearly
+ at all. POSIX 1003.1g doesn't define a lot of things
+ clearly however!
+
+ */
+ if (UNIXCB(skb).fp)
+ siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp);
+ }
+ err = size;
+
+ scm_recv(sock, msg, siocb->scm, flags);
+
+out_free:
+ skb_free_datagram(sk,skb);
+out_unlock:
+ up(&u->readsem);
+out:
+ return err;
+}
+
+/*
+ * Sleep until data has arrive. But check for races..
+ */
+
+static long unix_stream_data_wait(struct sock * sk, long timeo)
+{
+ DEFINE_WAIT(wait);
+
+ unix_state_rlock(sk);
+
+ for (;;) {
+ prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
+
+ if (skb_queue_len(&sk->sk_receive_queue) ||
+ sk->sk_err ||
+ (sk->sk_shutdown & RCV_SHUTDOWN) ||
+ signal_pending(current) ||
+ !timeo)
+ break;
+
+ set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+ unix_state_runlock(sk);
+ timeo = schedule_timeout(timeo);
+ unix_state_rlock(sk);
+ clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+ }
+
+ finish_wait(sk->sk_sleep, &wait);
+ unix_state_runlock(sk);
+ return timeo;
+}
+
+
+
+static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
+ struct msghdr *msg, size_t size,
+ int flags)
+{
+ struct sock_iocb *siocb = kiocb_to_siocb(iocb);
+ struct scm_cookie tmp_scm;
+ struct sock *sk = sock->sk;
+ struct unix_sock *u = unix_sk(sk);
+ struct sockaddr_un *sunaddr=msg->msg_name;
+ int copied = 0;
+ int check_creds = 0;
+ int target;
+ int err = 0;
+ long timeo;
+
+ err = -EINVAL;
+ if (sk->sk_state != TCP_ESTABLISHED)
+ goto out;
+
+ err = -EOPNOTSUPP;
+ if (flags&MSG_OOB)
+ goto out;
+
+ target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
+ timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
+
+ msg->msg_namelen = 0;
+
+ /* Lock the socket to prevent queue disordering
+ * while sleeps in memcpy_tomsg
+ */
+
+ if (!siocb->scm) {
+ siocb->scm = &tmp_scm;
+ memset(&tmp_scm, 0, sizeof(tmp_scm));
+ }
+
+ down(&u->readsem);
+
+ do
+ {
+ int chunk;
+ struct sk_buff *skb;
+
+ skb = skb_dequeue(&sk->sk_receive_queue);
+ if (skb==NULL)
+ {
+ if (copied >= target)
+ break;
+
+ /*
+ * POSIX 1003.1g mandates this order.
+ */
+
+ if ((err = sock_error(sk)) != 0)
+ break;
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ break;
+ err = -EAGAIN;
+ if (!timeo)
+ break;
+ up(&u->readsem);
+
+ timeo = unix_stream_data_wait(sk, timeo);
+
+ if (signal_pending(current)) {
+ err = sock_intr_errno(timeo);
+ goto out;
+ }
+ down(&u->readsem);
+ continue;
+ }
+
+ if (check_creds) {
+ /* Never glue messages from different writers */
+ if (memcmp(UNIXCREDS(skb), &siocb->scm->creds, sizeof(siocb->scm->creds)) != 0) {
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ break;
+ }
+ } else {
+ /* Copy credentials */
+ siocb->scm->creds = *UNIXCREDS(skb);
+ check_creds = 1;
+ }
+
+ /* Copy address just once */
+ if (sunaddr)
+ {
+ unix_copy_addr(msg, skb->sk);
+ sunaddr = NULL;
+ }
+
+ chunk = min_t(unsigned int, skb->len, size);
+ if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ if (copied == 0)
+ copied = -EFAULT;
+ break;
+ }
+ copied += chunk;
+ size -= chunk;
+
+ /* Mark read part of skb as used */
+ if (!(flags & MSG_PEEK))
+ {
+ skb_pull(skb, chunk);
+
+ if (UNIXCB(skb).fp)
+ unix_detach_fds(siocb->scm, skb);
+
+ /* put the skb back if we didn't use it up.. */
+ if (skb->len)
+ {
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ break;
+ }
+
+ kfree_skb(skb);
+
+ if (siocb->scm->fp)
+ break;
+ }
+ else
+ {
+ /* It is questionable, see note in unix_dgram_recvmsg.
+ */
+ if (UNIXCB(skb).fp)
+ siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp);
+
+ /* put message back and return */
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ break;
+ }
+ } while (size);
+
+ up(&u->readsem);
+ scm_recv(sock, msg, siocb->scm, flags);
+out:
+ return copied ? : err;
+}
+
+static int unix_shutdown(struct socket *sock, int mode)
+{
+ struct sock *sk = sock->sk;
+ struct sock *other;
+
+ mode = (mode+1)&(RCV_SHUTDOWN|SEND_SHUTDOWN);
+
+ if (mode) {
+ unix_state_wlock(sk);
+ sk->sk_shutdown |= mode;
+ other=unix_peer(sk);
+ if (other)
+ sock_hold(other);
+ unix_state_wunlock(sk);
+ sk->sk_state_change(sk);
+
+ if (other &&
+ (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET)) {
+
+ int peer_mode = 0;
+
+ if (mode&RCV_SHUTDOWN)
+ peer_mode |= SEND_SHUTDOWN;
+ if (mode&SEND_SHUTDOWN)
+ peer_mode |= RCV_SHUTDOWN;
+ unix_state_wlock(other);
+ other->sk_shutdown |= peer_mode;
+ unix_state_wunlock(other);
+ other->sk_state_change(other);
+ read_lock(&other->sk_callback_lock);
+ if (peer_mode == SHUTDOWN_MASK)
+ sk_wake_async(other,1,POLL_HUP);
+ else if (peer_mode & RCV_SHUTDOWN)
+ sk_wake_async(other,1,POLL_IN);
+ read_unlock(&other->sk_callback_lock);
+ }
+ if (other)
+ sock_put(other);
+ }
+ return 0;
+}
+
+static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+ struct sock *sk = sock->sk;
+ long amount=0;
+ int err;
+
+ switch(cmd)
+ {
+ case SIOCOUTQ:
+ amount = atomic_read(&sk->sk_wmem_alloc);
+ err = put_user(amount, (int __user *)arg);
+ break;
+ case SIOCINQ:
+ {
+ struct sk_buff *skb;
+
+ if (sk->sk_state == TCP_LISTEN) {
+ err = -EINVAL;
+ break;
+ }
+
+ spin_lock(&sk->sk_receive_queue.lock);
+ if (sk->sk_type == SOCK_STREAM ||
+ sk->sk_type == SOCK_SEQPACKET) {
+ skb_queue_walk(&sk->sk_receive_queue, skb)
+ amount += skb->len;
+ } else {
+ skb = skb_peek(&sk->sk_receive_queue);
+ if (skb)
+ amount=skb->len;
+ }
+ spin_unlock(&sk->sk_receive_queue.lock);
+ err = put_user(amount, (int __user *)arg);
+ break;
+ }
+
+ default:
+ err = dev_ioctl(cmd, (void __user *)arg);
+ break;
+ }
+ return err;
+}
+
+static unsigned int unix_poll(struct file * file, struct socket *sock, poll_table *wait)
+{
+ struct sock *sk = sock->sk;
+ unsigned int mask;
+
+ poll_wait(file, sk->sk_sleep, wait);
+ mask = 0;
+
+ /* exceptional events? */
+ if (sk->sk_err)
+ mask |= POLLERR;
+ if (sk->sk_shutdown == SHUTDOWN_MASK)
+ mask |= POLLHUP;
+
+ /* readable? */
+ if (!skb_queue_empty(&sk->sk_receive_queue) ||
+ (sk->sk_shutdown & RCV_SHUTDOWN))
+ mask |= POLLIN | POLLRDNORM;
+
+ /* Connection-based need to check for termination and startup */
+ if ((sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) && sk->sk_state == TCP_CLOSE)
+ mask |= POLLHUP;
+
+ /*
+ * we set writable also when the other side has shut down the
+ * connection. This prevents stuck sockets.
+ */
+ if (unix_writable(sk))
+ mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
+
+ return mask;
+}
+
+
+#ifdef CONFIG_PROC_FS
+static struct sock *unix_seq_idx(int *iter, loff_t pos)
+{
+ loff_t off = 0;
+ struct sock *s;
+
+ for (s = first_unix_socket(iter); s; s = next_unix_socket(iter, s)) {
+ if (off == pos)
+ return s;
+ ++off;
+ }
+ return NULL;
+}
+
+
+static void *unix_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ read_lock(&unix_table_lock);
+ return *pos ? unix_seq_idx(seq->private, *pos - 1) : ((void *) 1);
+}
+
+static void *unix_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ ++*pos;
+
+ if (v == (void *)1)
+ return first_unix_socket(seq->private);
+ return next_unix_socket(seq->private, v);
+}
+
+static void unix_seq_stop(struct seq_file *seq, void *v)
+{
+ read_unlock(&unix_table_lock);
+}
+
+static int unix_seq_show(struct seq_file *seq, void *v)
+{
+
+ if (v == (void *)1)
+ seq_puts(seq, "Num RefCount Protocol Flags Type St "
+ "Inode Path\n");
+ else {
+ struct sock *s = v;
+ struct unix_sock *u = unix_sk(s);
+ unix_state_rlock(s);
+
+ seq_printf(seq, "%p: %08X %08X %08X %04X %02X %5lu",
+ s,
+ atomic_read(&s->sk_refcnt),
+ 0,
+ s->sk_state == TCP_LISTEN ? __SO_ACCEPTCON : 0,
+ s->sk_type,
+ s->sk_socket ?
+ (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTED : SS_UNCONNECTED) :
+ (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING),
+ sock_i_ino(s));
+
+ if (u->addr) {
+ int i, len;
+ seq_putc(seq, ' ');
+
+ i = 0;
+ len = u->addr->len - sizeof(short);
+ if (!UNIX_ABSTRACT(s))
+ len--;
+ else {
+ seq_putc(seq, '@');
+ i++;
+ }
+ for ( ; i < len; i++)
+ seq_putc(seq, u->addr->name->sun_path[i]);
+ }
+ unix_state_runlock(s);
+ seq_putc(seq, '\n');
+ }
+
+ return 0;
+}
+
+static struct seq_operations unix_seq_ops = {
+ .start = unix_seq_start,
+ .next = unix_seq_next,
+ .stop = unix_seq_stop,
+ .show = unix_seq_show,
+};
+
+
+static int unix_seq_open(struct inode *inode, struct file *file)
+{
+ struct seq_file *seq;
+ int rc = -ENOMEM;
+ int *iter = kmalloc(sizeof(int), GFP_KERNEL);
+
+ if (!iter)
+ goto out;
+
+ rc = seq_open(file, &unix_seq_ops);
+ if (rc)
+ goto out_kfree;
+
+ seq = file->private_data;
+ seq->private = iter;
+ *iter = 0;
+out:
+ return rc;
+out_kfree:
+ kfree(iter);
+ goto out;
+}
+
+static struct file_operations unix_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = unix_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_private,
+};
+
+#endif
+
+static struct net_proto_family unix_family_ops = {
+ .family = PF_UNIX,
+ .create = unix_create,
+ .owner = THIS_MODULE,
+};
+
+#ifdef CONFIG_SYSCTL
+extern void unix_sysctl_register(void);
+extern void unix_sysctl_unregister(void);
+#else
+static inline void unix_sysctl_register(void) {}
+static inline void unix_sysctl_unregister(void) {}
+#endif
+
+static int __init af_unix_init(void)
+{
+ int rc = -1;
+ struct sk_buff *dummy_skb;
+
+ if (sizeof(struct unix_skb_parms) > sizeof(dummy_skb->cb)) {
+ printk(KERN_CRIT "%s: panic\n", __FUNCTION__);
+ goto out;
+ }
+
+ rc = proto_register(&unix_proto, 1);
+ if (rc != 0) {
+ printk(KERN_CRIT "%s: Cannot create unix_sock SLAB cache!\n",
+ __FUNCTION__);
+ goto out;
+ }
+
+ sock_register(&unix_family_ops);
+#ifdef CONFIG_PROC_FS
+ proc_net_fops_create("unix", 0, &unix_seq_fops);
+#endif
+ unix_sysctl_register();
+out:
+ return rc;
+}
+
+static void __exit af_unix_exit(void)
+{
+ sock_unregister(PF_UNIX);
+ unix_sysctl_unregister();
+ proc_net_remove("unix");
+ proto_unregister(&unix_proto);
+}
+
+module_init(af_unix_init);
+module_exit(af_unix_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(PF_UNIX);
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
new file mode 100644
index 000000000000..4bd95c8f5934
--- /dev/null
+++ b/net/unix/garbage.c
@@ -0,0 +1,312 @@
+/*
+ * NET3: Garbage Collector For AF_UNIX sockets
+ *
+ * Garbage Collector:
+ * Copyright (C) Barak A. Pearlmutter.
+ * Released under the GPL version 2 or later.
+ *
+ * Chopped about by Alan Cox 22/3/96 to make it fit the AF_UNIX socket problem.
+ * If it doesn't work blame me, it worked when Barak sent it.
+ *
+ * Assumptions:
+ *
+ * - object w/ a bit
+ * - free list
+ *
+ * Current optimizations:
+ *
+ * - explicit stack instead of recursion
+ * - tail recurse on first born instead of immediate push/pop
+ * - we gather the stuff that should not be killed into tree
+ * and stack is just a path from root to the current pointer.
+ *
+ * Future optimizations:
+ *
+ * - don't just push entire root set; process in place
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Fixes:
+ * Alan Cox 07 Sept 1997 Vmalloc internal stack as needed.
+ * Cope with changing max_files.
+ * Al Viro 11 Oct 1998
+ * Graph may have cycles. That is, we can send the descriptor
+ * of foo to bar and vice versa. Current code chokes on that.
+ * Fix: move SCM_RIGHTS ones into the separate list and then
+ * skb_free() them all instead of doing explicit fput's.
+ * Another problem: since fput() may block somebody may
+ * create a new unix_socket when we are in the middle of sweep
+ * phase. Fix: revert the logic wrt MARKED. Mark everything
+ * upon the beginning and unmark non-junk ones.
+ *
+ * [12 Oct 1998] AAARGH! New code purges all SCM_RIGHTS
+ * sent to connect()'ed but still not accept()'ed sockets.
+ * Fixed. Old code had slightly different problem here:
+ * extra fput() in situation when we passed the descriptor via
+ * such socket and closed it (descriptor). That would happen on
+ * each unix_gc() until the accept(). Since the struct file in
+ * question would go to the free list and might be reused...
+ * That might be the reason of random oopses on filp_close()
+ * in unrelated processes.
+ *
+ * AV 28 Feb 1999
+ * Kill the explicit allocation of stack. Now we keep the tree
+ * with root in dummy + pointer (gc_current) to one of the nodes.
+ * Stack is represented as path from gc_current to dummy. Unmark
+ * now means "add to tree". Push == "make it a son of gc_current".
+ * Pop == "move gc_current to parent". We keep only pointers to
+ * parents (->gc_tree).
+ * AV 1 Mar 1999
+ * Damn. Added missing check for ->dead in listen queues scanning.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/socket.h>
+#include <linux/un.h>
+#include <linux/net.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/file.h>
+#include <linux/proc_fs.h>
+#include <linux/tcp.h>
+
+#include <net/sock.h>
+#include <net/af_unix.h>
+#include <net/scm.h>
+
+/* Internal data structures and random procedures: */
+
+#define GC_HEAD ((struct sock *)(-1))
+#define GC_ORPHAN ((struct sock *)(-3))
+
+static struct sock *gc_current = GC_HEAD; /* stack of objects to mark */
+
+atomic_t unix_tot_inflight = ATOMIC_INIT(0);
+
+
+static struct sock *unix_get_socket(struct file *filp)
+{
+ struct sock *u_sock = NULL;
+ struct inode *inode = filp->f_dentry->d_inode;
+
+ /*
+ * Socket ?
+ */
+ if (S_ISSOCK(inode->i_mode)) {
+ struct socket * sock = SOCKET_I(inode);
+ struct sock * s = sock->sk;
+
+ /*
+ * PF_UNIX ?
+ */
+ if (s && sock->ops && sock->ops->family == PF_UNIX)
+ u_sock = s;
+ }
+ return u_sock;
+}
+
+/*
+ * Keep the number of times in flight count for the file
+ * descriptor if it is for an AF_UNIX socket.
+ */
+
+void unix_inflight(struct file *fp)
+{
+ struct sock *s = unix_get_socket(fp);
+ if(s) {
+ atomic_inc(&unix_sk(s)->inflight);
+ atomic_inc(&unix_tot_inflight);
+ }
+}
+
+void unix_notinflight(struct file *fp)
+{
+ struct sock *s = unix_get_socket(fp);
+ if(s) {
+ atomic_dec(&unix_sk(s)->inflight);
+ atomic_dec(&unix_tot_inflight);
+ }
+}
+
+
+/*
+ * Garbage Collector Support Functions
+ */
+
+static inline struct sock *pop_stack(void)
+{
+ struct sock *p = gc_current;
+ gc_current = unix_sk(p)->gc_tree;
+ return p;
+}
+
+static inline int empty_stack(void)
+{
+ return gc_current == GC_HEAD;
+}
+
+static void maybe_unmark_and_push(struct sock *x)
+{
+ struct unix_sock *u = unix_sk(x);
+
+ if (u->gc_tree != GC_ORPHAN)
+ return;
+ sock_hold(x);
+ u->gc_tree = gc_current;
+ gc_current = x;
+}
+
+
+/* The external entry point: unix_gc() */
+
+void unix_gc(void)
+{
+ static DECLARE_MUTEX(unix_gc_sem);
+ int i;
+ struct sock *s;
+ struct sk_buff_head hitlist;
+ struct sk_buff *skb;
+
+ /*
+ * Avoid a recursive GC.
+ */
+
+ if (down_trylock(&unix_gc_sem))
+ return;
+
+ read_lock(&unix_table_lock);
+
+ forall_unix_sockets(i, s)
+ {
+ unix_sk(s)->gc_tree = GC_ORPHAN;
+ }
+ /*
+ * Everything is now marked
+ */
+
+ /* Invariant to be maintained:
+ - everything unmarked is either:
+ -- (a) on the stack, or
+ -- (b) has all of its children unmarked
+ - everything on the stack is always unmarked
+ - nothing is ever pushed onto the stack twice, because:
+ -- nothing previously unmarked is ever pushed on the stack
+ */
+
+ /*
+ * Push root set
+ */
+
+ forall_unix_sockets(i, s)
+ {
+ int open_count = 0;
+
+ /*
+ * If all instances of the descriptor are not
+ * in flight we are in use.
+ *
+ * Special case: when socket s is embrion, it may be
+ * hashed but still not in queue of listening socket.
+ * In this case (see unix_create1()) we set artificial
+ * negative inflight counter to close race window.
+ * It is trick of course and dirty one.
+ */
+ if (s->sk_socket && s->sk_socket->file)
+ open_count = file_count(s->sk_socket->file);
+ if (open_count > atomic_read(&unix_sk(s)->inflight))
+ maybe_unmark_and_push(s);
+ }
+
+ /*
+ * Mark phase
+ */
+
+ while (!empty_stack())
+ {
+ struct sock *x = pop_stack();
+ struct sock *sk;
+
+ spin_lock(&x->sk_receive_queue.lock);
+ skb = skb_peek(&x->sk_receive_queue);
+
+ /*
+ * Loop through all but first born
+ */
+
+ while (skb && skb != (struct sk_buff *)&x->sk_receive_queue) {
+ /*
+ * Do we have file descriptors ?
+ */
+ if(UNIXCB(skb).fp)
+ {
+ /*
+ * Process the descriptors of this socket
+ */
+ int nfd=UNIXCB(skb).fp->count;
+ struct file **fp = UNIXCB(skb).fp->fp;
+ while(nfd--)
+ {
+ /*
+ * Get the socket the fd matches if
+ * it indeed does so
+ */
+ if((sk=unix_get_socket(*fp++))!=NULL)
+ {
+ maybe_unmark_and_push(sk);
+ }
+ }
+ }
+ /* We have to scan not-yet-accepted ones too */
+ if (x->sk_state == TCP_LISTEN)
+ maybe_unmark_and_push(skb->sk);
+ skb=skb->next;
+ }
+ spin_unlock(&x->sk_receive_queue.lock);
+ sock_put(x);
+ }
+
+ skb_queue_head_init(&hitlist);
+
+ forall_unix_sockets(i, s)
+ {
+ struct unix_sock *u = unix_sk(s);
+
+ if (u->gc_tree == GC_ORPHAN) {
+ struct sk_buff *nextsk;
+
+ spin_lock(&s->sk_receive_queue.lock);
+ skb = skb_peek(&s->sk_receive_queue);
+ while (skb &&
+ skb != (struct sk_buff *)&s->sk_receive_queue) {
+ nextsk=skb->next;
+ /*
+ * Do we have file descriptors ?
+ */
+ if(UNIXCB(skb).fp)
+ {
+ __skb_unlink(skb, skb->list);
+ __skb_queue_tail(&hitlist,skb);
+ }
+ skb=nextsk;
+ }
+ spin_unlock(&s->sk_receive_queue.lock);
+ }
+ u->gc_tree = GC_ORPHAN;
+ }
+ read_unlock(&unix_table_lock);
+
+ /*
+ * Here we are. Hitlist is filled. Die.
+ */
+
+ __skb_queue_purge(&hitlist);
+ up(&unix_gc_sem);
+}
diff --git a/net/unix/sysctl_net_unix.c b/net/unix/sysctl_net_unix.c
new file mode 100644
index 000000000000..c974dac4580a
--- /dev/null
+++ b/net/unix/sysctl_net_unix.c
@@ -0,0 +1,60 @@
+/*
+ * NET4: Sysctl interface to net af_unix subsystem.
+ *
+ * Authors: Mike Shaver.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/mm.h>
+#include <linux/sysctl.h>
+
+extern int sysctl_unix_max_dgram_qlen;
+
+static ctl_table unix_table[] = {
+ {
+ .ctl_name = NET_UNIX_MAX_DGRAM_QLEN,
+ .procname = "max_dgram_qlen",
+ .data = &sysctl_unix_max_dgram_qlen,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec
+ },
+ { .ctl_name = 0 }
+};
+
+static ctl_table unix_net_table[] = {
+ {
+ .ctl_name = NET_UNIX,
+ .procname = "unix",
+ .mode = 0555,
+ .child = unix_table
+ },
+ { .ctl_name = 0 }
+};
+
+static ctl_table unix_root_table[] = {
+ {
+ .ctl_name = CTL_NET,
+ .procname = "net",
+ .mode = 0555,
+ .child = unix_net_table
+ },
+ { .ctl_name = 0 }
+};
+
+static struct ctl_table_header * unix_sysctl_header;
+
+void unix_sysctl_register(void)
+{
+ unix_sysctl_header = register_sysctl_table(unix_root_table, 0);
+}
+
+void unix_sysctl_unregister(void)
+{
+ unregister_sysctl_table(unix_sysctl_header);
+}
+