diff options
Diffstat (limited to 'net/unix/af_unix.c')
-rw-r--r-- | net/unix/af_unix.c | 260 |
1 files changed, 130 insertions, 130 deletions
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 79981d97bc9c..c1f403bed683 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -114,6 +114,7 @@ #include <linux/mount.h> #include <net/checksum.h> #include <linux/security.h> +#include <linux/freezer.h> struct hlist_head unix_socket_table[2 * UNIX_HASH_SIZE]; EXPORT_SYMBOL_GPL(unix_socket_table); @@ -263,9 +264,8 @@ static struct sock *__unix_find_socket_byname(struct net *net, int len, int type, unsigned int hash) { struct sock *s; - struct hlist_node *node; - sk_for_each(s, node, &unix_socket_table[hash ^ type]) { + sk_for_each(s, &unix_socket_table[hash ^ type]) { struct unix_sock *u = unix_sk(s); if (!net_eq(sock_net(s), net)) @@ -298,10 +298,9 @@ static inline struct sock *unix_find_socket_byname(struct net *net, static struct sock *unix_find_socket_byinode(struct inode *i) { struct sock *s; - struct hlist_node *node; spin_lock(&unix_table_lock); - sk_for_each(s, node, + sk_for_each(s, &unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) { struct dentry *dentry = unix_sk(s)->path.dentry; @@ -384,7 +383,7 @@ static void unix_sock_destructor(struct sock *sk) #endif } -static int unix_release_sock(struct sock *sk, int embrion) +static void unix_release_sock(struct sock *sk, int embrion) { struct unix_sock *u = unix_sk(sk); struct path path; @@ -441,7 +440,7 @@ static int unix_release_sock(struct sock *sk, int embrion) /* ---- Socket is dead now and most probably destroyed ---- */ /* - * Fixme: BSD difference: In BSD all sockets connected to use get + * Fixme: BSD difference: In BSD all sockets connected to us get * ECONNRESET and we die on the spot. In Linux we behave * like files and pipes do and wait for the last * dereference. @@ -453,8 +452,6 @@ static int unix_release_sock(struct sock *sk, int embrion) if (unix_tot_inflight) unix_gc(); /* Garbage collect fds */ - - return 0; } static void init_peercred(struct sock *sk) @@ -481,7 +478,6 @@ static int unix_listen(struct socket *sock, int backlog) struct sock *sk = sock->sk; struct unix_sock *u = unix_sk(sk); struct pid *old_pid = NULL; - const struct cred *old_cred = NULL; err = -EOPNOTSUPP; if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET) @@ -503,8 +499,6 @@ static int unix_listen(struct socket *sock, int backlog) out_unlock: unix_state_unlock(sk); put_pid(old_pid); - if (old_cred) - put_cred(old_cred); out: return err; } @@ -704,9 +698,10 @@ static int unix_release(struct socket *sock) if (!sk) return 0; + unix_release_sock(sk, 0); sock->sk = NULL; - return unix_release_sock(sk, 0); + return 0; } static int unix_autobind(struct socket *sock) @@ -823,6 +818,34 @@ fail: return NULL; } +static int unix_mknod(const char *sun_path, umode_t mode, struct path *res) +{ + struct dentry *dentry; + struct path path; + int err = 0; + /* + * Get the parent directory, calculate the hash for last + * component. + */ + dentry = kern_path_create(AT_FDCWD, sun_path, &path, 0); + err = PTR_ERR(dentry); + if (IS_ERR(dentry)) + return err; + + /* + * All right, let's create it. + */ + err = security_path_mknod(&path, dentry, mode, 0); + if (!err) { + err = vfs_mknod(path.dentry->d_inode, dentry, mode, 0); + if (!err) { + res->mnt = mntget(path.mnt); + res->dentry = dget(dentry); + } + } + done_path_create(&path, dentry); + return err; +} static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) { @@ -831,8 +854,6 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) struct unix_sock *u = unix_sk(sk); struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr; char *sun_path = sunaddr->sun_path; - struct dentry *dentry = NULL; - struct path path; int err; unsigned int hash; struct unix_address *addr; @@ -869,43 +890,23 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) atomic_set(&addr->refcnt, 1); if (sun_path[0]) { - umode_t mode; - err = 0; - /* - * Get the parent directory, calculate the hash for last - * component. - */ - dentry = kern_path_create(AT_FDCWD, sun_path, &path, 0); - err = PTR_ERR(dentry); - if (IS_ERR(dentry)) - goto out_mknod_parent; - - /* - * All right, let's create it. - */ - mode = S_IFSOCK | + struct path path; + umode_t mode = S_IFSOCK | (SOCK_INODE(sock)->i_mode & ~current_umask()); - err = mnt_want_write(path.mnt); - if (err) - goto out_mknod_dput; - err = security_path_mknod(&path, dentry, mode, 0); - if (err) - goto out_mknod_drop_write; - err = vfs_mknod(path.dentry->d_inode, dentry, mode, 0); -out_mknod_drop_write: - mnt_drop_write(path.mnt); - if (err) - goto out_mknod_dput; - mutex_unlock(&path.dentry->d_inode->i_mutex); - dput(path.dentry); - path.dentry = dentry; - + err = unix_mknod(sun_path, mode, &path); + if (err) { + if (err == -EEXIST) + err = -EADDRINUSE; + unix_release_addr(addr); + goto out_up; + } addr->hash = UNIX_HASH_SIZE; - } - - spin_lock(&unix_table_lock); - - if (!sun_path[0]) { + hash = path.dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1); + spin_lock(&unix_table_lock); + u->path = path; + list = &unix_socket_table[hash]; + } else { + spin_lock(&unix_table_lock); err = -EADDRINUSE; if (__unix_find_socket_byname(net, sunaddr, addr_len, sk->sk_type, hash)) { @@ -914,9 +915,6 @@ out_mknod_drop_write: } list = &unix_socket_table[addr->hash]; - } else { - list = &unix_socket_table[dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1)]; - u->path = path; } err = 0; @@ -930,16 +928,6 @@ out_up: mutex_unlock(&u->readlock); out: return err; - -out_mknod_dput: - dput(dentry); - mutex_unlock(&path.dentry->d_inode->i_mutex); - path_put(&path); -out_mknod_parent: - if (err == -EEXIST) - err = -EADDRINUSE; - unix_release_addr(addr); - goto out_up; } static void unix_state_double_lock(struct sock *sk1, struct sock *sk2) @@ -1258,6 +1246,15 @@ static int unix_socketpair(struct socket *socka, struct socket *sockb) return 0; } +static void unix_sock_inherit_flags(const struct socket *old, + struct socket *new) +{ + if (test_bit(SOCK_PASSCRED, &old->flags)) + set_bit(SOCK_PASSCRED, &new->flags); + if (test_bit(SOCK_PASSSEC, &old->flags)) + set_bit(SOCK_PASSSEC, &new->flags); +} + static int unix_accept(struct socket *sock, struct socket *newsock, int flags) { struct sock *sk = sock->sk; @@ -1292,6 +1289,7 @@ static int unix_accept(struct socket *sock, struct socket *newsock, int flags) /* attach accepted sock to socket */ unix_state_lock(tsk); newsock->state = SS_CONNECTED; + unix_sock_inherit_flags(sock, newsock); sock_graft(tsk, newsock); unix_state_unlock(tsk); return 0; @@ -1353,7 +1351,6 @@ static void unix_destruct_scm(struct sk_buff *skb) struct scm_cookie scm; memset(&scm, 0, sizeof(scm)); scm.pid = UNIXCB(skb).pid; - scm.cred = UNIXCB(skb).cred; if (UNIXCB(skb).fp) unix_detach_fds(&scm, skb); @@ -1404,8 +1401,8 @@ static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool sen int err = 0; UNIXCB(skb).pid = get_pid(scm->pid); - if (scm->cred) - UNIXCB(skb).cred = get_cred(scm->cred); + UNIXCB(skb).uid = scm->creds.uid; + UNIXCB(skb).gid = scm->creds.gid; UNIXCB(skb).fp = NULL; if (scm->fp && send_fds) err = unix_attach_fds(scm, skb); @@ -1422,13 +1419,13 @@ static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool sen static void maybe_add_creds(struct sk_buff *skb, const struct socket *sock, const struct sock *other) { - if (UNIXCB(skb).cred) + if (UNIXCB(skb).pid) return; if (test_bit(SOCK_PASSCRED, &sock->flags) || !other->sk_socket || test_bit(SOCK_PASSCRED, &other->sk_socket->flags)) { UNIXCB(skb).pid = get_pid(task_tgid(current)); - UNIXCB(skb).cred = get_current_cred(); + current_uid_gid(&UNIXCB(skb).uid, &UNIXCB(skb).gid); } } @@ -1457,7 +1454,7 @@ static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, if (NULL == siocb->scm) siocb->scm = &tmp_scm; wait_for_unix_gc(); - err = scm_send(sock, msg, siocb->scm); + err = scm_send(sock, msg, siocb->scm, false); if (err < 0) return err; @@ -1492,7 +1489,8 @@ static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, MAX_SKB_FRAGS * PAGE_SIZE); skb = sock_alloc_send_pskb(sk, len - data_len, data_len, - msg->msg_flags & MSG_DONTWAIT, &err); + msg->msg_flags & MSG_DONTWAIT, &err, + PAGE_ALLOC_COSTLY_ORDER); if (skb == NULL) goto out; @@ -1609,6 +1607,10 @@ out: return err; } +/* We use paged skbs for stream sockets, and limit occupancy to 32768 + * bytes, and a minimun of a full page. + */ +#define UNIX_SKB_FRAGS_SZ (PAGE_SIZE << get_order(32768)) static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, struct msghdr *msg, size_t len) @@ -1622,11 +1624,12 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, struct scm_cookie tmp_scm; bool fds_sent = false; int max_level; + int data_len; if (NULL == siocb->scm) siocb->scm = &tmp_scm; wait_for_unix_gc(); - err = scm_send(sock, msg, siocb->scm); + err = scm_send(sock, msg, siocb->scm, false); if (err < 0) return err; @@ -1648,40 +1651,22 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, goto pipe_err; while (sent < len) { - /* - * Optimisation for the fact that under 0.01% of X - * messages typically need breaking up. - */ - - size = len-sent; + size = len - sent; /* Keep two messages in the pipe so it schedules better */ - if (size > ((sk->sk_sndbuf >> 1) - 64)) - size = (sk->sk_sndbuf >> 1) - 64; + size = min_t(int, size, (sk->sk_sndbuf >> 1) - 64); - if (size > SKB_MAX_ALLOC) - size = SKB_MAX_ALLOC; + /* allow fallback to order-0 allocations */ + size = min_t(int, size, SKB_MAX_HEAD(0) + UNIX_SKB_FRAGS_SZ); - /* - * Grab a buffer - */ + data_len = max_t(int, 0, size - SKB_MAX_HEAD(0)); - skb = sock_alloc_send_skb(sk, size, msg->msg_flags&MSG_DONTWAIT, - &err); - - if (skb == NULL) + skb = sock_alloc_send_pskb(sk, size - data_len, data_len, + msg->msg_flags & MSG_DONTWAIT, &err, + get_order(UNIX_SKB_FRAGS_SZ)); + if (!skb) 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)); - - /* Only send the fds in the first buffer */ err = unix_scm_to_skb(siocb->scm, skb, !fds_sent); if (err < 0) { @@ -1691,7 +1676,11 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, max_level = err + 1; fds_sent = true; - err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size); + skb_put(skb, size - data_len); + skb->data_len = data_len; + skb->len = size; + err = skb_copy_datagram_from_iovec(skb, 0, msg->msg_iov, + sent, size); if (err) { kfree_skb(skb); goto out_err; @@ -1832,7 +1821,7 @@ static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock, siocb->scm = &tmp_scm; memset(&tmp_scm, 0, sizeof(tmp_scm)); } - scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); + scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid); unix_set_secdata(siocb->scm, skb); if (!(flags & MSG_PEEK)) { @@ -1872,10 +1861,10 @@ out: } /* - * Sleep until data has arrive. But check for races.. + * Sleep until more data has arrived. But check for races.. */ - -static long unix_stream_data_wait(struct sock *sk, long timeo) +static long unix_stream_data_wait(struct sock *sk, long timeo, + struct sk_buff *last) { DEFINE_WAIT(wait); @@ -1884,7 +1873,7 @@ static long unix_stream_data_wait(struct sock *sk, long timeo) for (;;) { prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); - if (!skb_queue_empty(&sk->sk_receive_queue) || + if (skb_peek_tail(&sk->sk_receive_queue) != last || sk->sk_err || (sk->sk_shutdown & RCV_SHUTDOWN) || signal_pending(current) || @@ -1893,7 +1882,7 @@ static long unix_stream_data_wait(struct sock *sk, long timeo) set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); unix_state_unlock(sk); - timeo = schedule_timeout(timeo); + timeo = freezable_schedule_timeout(timeo); unix_state_lock(sk); clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); } @@ -1903,7 +1892,10 @@ static long unix_stream_data_wait(struct sock *sk, long timeo) return timeo; } - +static unsigned int unix_skb_len(const struct sk_buff *skb) +{ + return skb->len - UNIXCB(skb).consumed; +} static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t size, @@ -1949,14 +1941,12 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock, goto out; } - skip = sk_peek_offset(sk, flags); - do { int chunk; - struct sk_buff *skb; + struct sk_buff *skb, *last; unix_state_lock(sk); - skb = skb_peek(&sk->sk_receive_queue); + last = skb = skb_peek(&sk->sk_receive_queue); again: if (skb == NULL) { unix_sk(sk)->recursion_level = 0; @@ -1979,7 +1969,7 @@ again: break; mutex_unlock(&u->readlock); - timeo = unix_stream_data_wait(sk, timeo); + timeo = unix_stream_data_wait(sk, timeo, last); if (signal_pending(current) || mutex_lock_interruptible(&u->readlock)) { @@ -1993,10 +1983,13 @@ again: break; } - if (skip >= skb->len) { - skip -= skb->len; + skip = sk_peek_offset(sk, flags); + while (skip >= unix_skb_len(skb)) { + skip -= unix_skb_len(skb); + last = skb; skb = skb_peek_next(skb, &sk->sk_receive_queue); - goto again; + if (!skb) + goto again; } unix_state_unlock(sk); @@ -2004,11 +1997,12 @@ again: if (check_creds) { /* Never glue messages from different writers */ if ((UNIXCB(skb).pid != siocb->scm->pid) || - (UNIXCB(skb).cred != siocb->scm->cred)) + !uid_eq(UNIXCB(skb).uid, siocb->scm->creds.uid) || + !gid_eq(UNIXCB(skb).gid, siocb->scm->creds.gid)) break; - } else { + } else if (test_bit(SOCK_PASSCRED, &sock->flags)) { /* Copy credentials */ - scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); + scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid); check_creds = 1; } @@ -2018,8 +2012,9 @@ again: sunaddr = NULL; } - chunk = min_t(unsigned int, skb->len - skip, size); - if (memcpy_toiovec(msg->msg_iov, skb->data + skip, chunk)) { + chunk = min_t(unsigned int, unix_skb_len(skb) - skip, size); + if (skb_copy_datagram_iovec(skb, UNIXCB(skb).consumed + skip, + msg->msg_iov, chunk)) { if (copied == 0) copied = -EFAULT; break; @@ -2029,14 +2024,14 @@ again: /* Mark read part of skb as used */ if (!(flags & MSG_PEEK)) { - skb_pull(skb, chunk); + UNIXCB(skb).consumed += chunk; sk_peek_offset_bwd(sk, chunk); if (UNIXCB(skb).fp) unix_detach_fds(siocb->scm, skb); - if (skb->len) + if (unix_skb_len(skb)) break; skb_unlink(skb, &sk->sk_receive_queue); @@ -2067,10 +2062,14 @@ 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) - return 0; + if (mode < SHUT_RD || mode > SHUT_RDWR) + return -EINVAL; + /* This maps: + * SHUT_RD (0) -> RCV_SHUTDOWN (1) + * SHUT_WR (1) -> SEND_SHUTDOWN (2) + * SHUT_RDWR (2) -> SHUTDOWN_MASK (3) + */ + ++mode; unix_state_lock(sk); sk->sk_shutdown |= mode; @@ -2116,7 +2115,7 @@ long unix_inq_len(struct sock *sk) if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) { skb_queue_walk(&sk->sk_receive_queue, skb) - amount += skb->len; + amount += unix_skb_len(skb); } else { skb = skb_peek(&sk->sk_receive_queue); if (skb) @@ -2205,7 +2204,9 @@ static unsigned int unix_dgram_poll(struct file *file, struct socket *sock, /* exceptional events? */ if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue)) - mask |= POLLERR; + mask |= POLLERR | + (sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0); + if (sk->sk_shutdown & RCV_SHUTDOWN) mask |= POLLRDHUP | POLLIN | POLLRDNORM; if (sk->sk_shutdown == SHUTDOWN_MASK) @@ -2408,7 +2409,7 @@ static int __net_init unix_net_init(struct net *net) goto out; #ifdef CONFIG_PROC_FS - if (!proc_net_fops_create(net, "unix", 0, &unix_seq_fops)) { + if (!proc_create("unix", 0, net->proc_net, &unix_seq_fops)) { unix_sysctl_unregister(net); goto out; } @@ -2421,7 +2422,7 @@ out: static void __net_exit unix_net_exit(struct net *net) { unix_sysctl_unregister(net); - proc_net_remove(net, "unix"); + remove_proc_entry("unix", net->proc_net); } static struct pernet_operations unix_net_ops = { @@ -2432,9 +2433,8 @@ static struct pernet_operations unix_net_ops = { static int __init af_unix_init(void) { int rc = -1; - struct sk_buff *dummy_skb; - BUILD_BUG_ON(sizeof(struct unix_skb_parms) > sizeof(dummy_skb->cb)); + BUILD_BUG_ON(sizeof(struct unix_skb_parms) > FIELD_SIZEOF(struct sk_buff, cb)); rc = proto_register(&unix_proto, 1); if (rc != 0) { |