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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * NET4: Implementation of BSD Unix domain sockets. | |
3 | * | |
113aa838 | 4 | * Authors: Alan Cox, <alan@lxorguk.ukuu.org.uk> |
1da177e4 LT |
5 | * |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | * | |
1da177e4 LT |
11 | * Fixes: |
12 | * Linus Torvalds : Assorted bug cures. | |
13 | * Niibe Yutaka : async I/O support. | |
14 | * Carsten Paeth : PF_UNIX check, address fixes. | |
15 | * Alan Cox : Limit size of allocated blocks. | |
16 | * Alan Cox : Fixed the stupid socketpair bug. | |
17 | * Alan Cox : BSD compatibility fine tuning. | |
18 | * Alan Cox : Fixed a bug in connect when interrupted. | |
19 | * Alan Cox : Sorted out a proper draft version of | |
20 | * file descriptor passing hacked up from | |
21 | * Mike Shaver's work. | |
22 | * Marty Leisner : Fixes to fd passing | |
23 | * Nick Nevin : recvmsg bugfix. | |
24 | * Alan Cox : Started proper garbage collector | |
25 | * Heiko EiBfeldt : Missing verify_area check | |
26 | * Alan Cox : Started POSIXisms | |
27 | * Andreas Schwab : Replace inode by dentry for proper | |
28 | * reference counting | |
29 | * Kirk Petersen : Made this a module | |
30 | * Christoph Rohland : Elegant non-blocking accept/connect algorithm. | |
31 | * Lots of bug fixes. | |
32 | * Alexey Kuznetosv : Repaired (I hope) bugs introduces | |
33 | * by above two patches. | |
34 | * Andrea Arcangeli : If possible we block in connect(2) | |
35 | * if the max backlog of the listen socket | |
36 | * is been reached. This won't break | |
37 | * old apps and it will avoid huge amount | |
38 | * of socks hashed (this for unix_gc() | |
39 | * performances reasons). | |
40 | * Security fix that limits the max | |
41 | * number of socks to 2*max_files and | |
42 | * the number of skb queueable in the | |
43 | * dgram receiver. | |
44 | * Artur Skawina : Hash function optimizations | |
45 | * Alexey Kuznetsov : Full scale SMP. Lot of bugs are introduced 8) | |
46 | * Malcolm Beattie : Set peercred for socketpair | |
47 | * Michal Ostrowski : Module initialization cleanup. | |
48 | * Arnaldo C. Melo : Remove MOD_{INC,DEC}_USE_COUNT, | |
49 | * the core infrastructure is doing that | |
50 | * for all net proto families now (2.5.69+) | |
51 | * | |
52 | * | |
53 | * Known differences from reference BSD that was tested: | |
54 | * | |
55 | * [TO FIX] | |
56 | * ECONNREFUSED is not returned from one end of a connected() socket to the | |
57 | * other the moment one end closes. | |
58 | * fstat() doesn't return st_dev=0, and give the blksize as high water mark | |
59 | * and a fake inode identifier (nor the BSD first socket fstat twice bug). | |
60 | * [NOT TO FIX] | |
61 | * accept() returns a path name even if the connecting socket has closed | |
62 | * in the meantime (BSD loses the path and gives up). | |
63 | * accept() returns 0 length path for an unbound connector. BSD returns 16 | |
64 | * and a null first byte in the path (but not for gethost/peername - BSD bug ??) | |
65 | * socketpair(...SOCK_RAW..) doesn't panic the kernel. | |
66 | * BSD af_unix apparently has connect forgetting to block properly. | |
67 | * (need to check this with the POSIX spec in detail) | |
68 | * | |
69 | * Differences from 2.0.0-11-... (ANK) | |
70 | * Bug fixes and improvements. | |
71 | * - client shutdown killed server socket. | |
72 | * - removed all useless cli/sti pairs. | |
73 | * | |
74 | * Semantic changes/extensions. | |
75 | * - generic control message passing. | |
76 | * - SCM_CREDENTIALS control message. | |
77 | * - "Abstract" (not FS based) socket bindings. | |
78 | * Abstract names are sequences of bytes (not zero terminated) | |
79 | * started by 0, so that this name space does not intersect | |
80 | * with BSD names. | |
81 | */ | |
82 | ||
83 | #include <linux/module.h> | |
1da177e4 | 84 | #include <linux/kernel.h> |
1da177e4 LT |
85 | #include <linux/signal.h> |
86 | #include <linux/sched.h> | |
87 | #include <linux/errno.h> | |
88 | #include <linux/string.h> | |
89 | #include <linux/stat.h> | |
90 | #include <linux/dcache.h> | |
91 | #include <linux/namei.h> | |
92 | #include <linux/socket.h> | |
93 | #include <linux/un.h> | |
94 | #include <linux/fcntl.h> | |
95 | #include <linux/termios.h> | |
96 | #include <linux/sockios.h> | |
97 | #include <linux/net.h> | |
98 | #include <linux/in.h> | |
99 | #include <linux/fs.h> | |
100 | #include <linux/slab.h> | |
101 | #include <asm/uaccess.h> | |
102 | #include <linux/skbuff.h> | |
103 | #include <linux/netdevice.h> | |
457c4cbc | 104 | #include <net/net_namespace.h> |
1da177e4 | 105 | #include <net/sock.h> |
c752f073 | 106 | #include <net/tcp_states.h> |
1da177e4 LT |
107 | #include <net/af_unix.h> |
108 | #include <linux/proc_fs.h> | |
109 | #include <linux/seq_file.h> | |
110 | #include <net/scm.h> | |
111 | #include <linux/init.h> | |
112 | #include <linux/poll.h> | |
1da177e4 LT |
113 | #include <linux/rtnetlink.h> |
114 | #include <linux/mount.h> | |
115 | #include <net/checksum.h> | |
116 | #include <linux/security.h> | |
117 | ||
13111698 AB |
118 | static struct hlist_head unix_socket_table[UNIX_HASH_SIZE + 1]; |
119 | static DEFINE_SPINLOCK(unix_table_lock); | |
518de9b3 | 120 | static atomic_long_t unix_nr_socks; |
1da177e4 LT |
121 | |
122 | #define unix_sockets_unbound (&unix_socket_table[UNIX_HASH_SIZE]) | |
123 | ||
124 | #define UNIX_ABSTRACT(sk) (unix_sk(sk)->addr->hash != UNIX_HASH_SIZE) | |
125 | ||
877ce7c1 | 126 | #ifdef CONFIG_SECURITY_NETWORK |
dc49c1f9 | 127 | static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) |
877ce7c1 | 128 | { |
dc49c1f9 | 129 | memcpy(UNIXSID(skb), &scm->secid, sizeof(u32)); |
877ce7c1 CZ |
130 | } |
131 | ||
132 | static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) | |
133 | { | |
dc49c1f9 | 134 | scm->secid = *UNIXSID(skb); |
877ce7c1 CZ |
135 | } |
136 | #else | |
dc49c1f9 | 137 | static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) |
877ce7c1 CZ |
138 | { } |
139 | ||
140 | static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) | |
141 | { } | |
142 | #endif /* CONFIG_SECURITY_NETWORK */ | |
143 | ||
1da177e4 LT |
144 | /* |
145 | * SMP locking strategy: | |
fbe9cc4a | 146 | * hash table is protected with spinlock unix_table_lock |
663717f6 | 147 | * each socket state is protected by separate spin lock. |
1da177e4 LT |
148 | */ |
149 | ||
44bb9363 | 150 | static inline unsigned unix_hash_fold(__wsum n) |
1da177e4 | 151 | { |
44bb9363 | 152 | unsigned hash = (__force unsigned)n; |
1da177e4 LT |
153 | hash ^= hash>>16; |
154 | hash ^= hash>>8; | |
155 | return hash&(UNIX_HASH_SIZE-1); | |
156 | } | |
157 | ||
158 | #define unix_peer(sk) (unix_sk(sk)->peer) | |
159 | ||
160 | static inline int unix_our_peer(struct sock *sk, struct sock *osk) | |
161 | { | |
162 | return unix_peer(osk) == sk; | |
163 | } | |
164 | ||
165 | static inline int unix_may_send(struct sock *sk, struct sock *osk) | |
166 | { | |
6eba6a37 | 167 | return unix_peer(osk) == NULL || unix_our_peer(sk, osk); |
1da177e4 LT |
168 | } |
169 | ||
3c73419c RW |
170 | static inline int unix_recvq_full(struct sock const *sk) |
171 | { | |
172 | return skb_queue_len(&sk->sk_receive_queue) > sk->sk_max_ack_backlog; | |
173 | } | |
174 | ||
1da177e4 LT |
175 | static struct sock *unix_peer_get(struct sock *s) |
176 | { | |
177 | struct sock *peer; | |
178 | ||
1c92b4e5 | 179 | unix_state_lock(s); |
1da177e4 LT |
180 | peer = unix_peer(s); |
181 | if (peer) | |
182 | sock_hold(peer); | |
1c92b4e5 | 183 | unix_state_unlock(s); |
1da177e4 LT |
184 | return peer; |
185 | } | |
186 | ||
187 | static inline void unix_release_addr(struct unix_address *addr) | |
188 | { | |
189 | if (atomic_dec_and_test(&addr->refcnt)) | |
190 | kfree(addr); | |
191 | } | |
192 | ||
193 | /* | |
194 | * Check unix socket name: | |
195 | * - should be not zero length. | |
196 | * - if started by not zero, should be NULL terminated (FS object) | |
197 | * - if started by zero, it is abstract name. | |
198 | */ | |
ac7bfa62 | 199 | |
6eba6a37 | 200 | static int unix_mkname(struct sockaddr_un *sunaddr, int len, unsigned *hashp) |
1da177e4 LT |
201 | { |
202 | if (len <= sizeof(short) || len > sizeof(*sunaddr)) | |
203 | return -EINVAL; | |
204 | if (!sunaddr || sunaddr->sun_family != AF_UNIX) | |
205 | return -EINVAL; | |
206 | if (sunaddr->sun_path[0]) { | |
207 | /* | |
208 | * This may look like an off by one error but it is a bit more | |
209 | * subtle. 108 is the longest valid AF_UNIX path for a binding. | |
25985edc | 210 | * sun_path[108] doesn't as such exist. However in kernel space |
1da177e4 LT |
211 | * we are guaranteed that it is a valid memory location in our |
212 | * kernel address buffer. | |
213 | */ | |
e27dfcea | 214 | ((char *)sunaddr)[len] = 0; |
1da177e4 LT |
215 | len = strlen(sunaddr->sun_path)+1+sizeof(short); |
216 | return len; | |
217 | } | |
218 | ||
07f0757a | 219 | *hashp = unix_hash_fold(csum_partial(sunaddr, len, 0)); |
1da177e4 LT |
220 | return len; |
221 | } | |
222 | ||
223 | static void __unix_remove_socket(struct sock *sk) | |
224 | { | |
225 | sk_del_node_init(sk); | |
226 | } | |
227 | ||
228 | static void __unix_insert_socket(struct hlist_head *list, struct sock *sk) | |
229 | { | |
547b792c | 230 | WARN_ON(!sk_unhashed(sk)); |
1da177e4 LT |
231 | sk_add_node(sk, list); |
232 | } | |
233 | ||
234 | static inline void unix_remove_socket(struct sock *sk) | |
235 | { | |
fbe9cc4a | 236 | spin_lock(&unix_table_lock); |
1da177e4 | 237 | __unix_remove_socket(sk); |
fbe9cc4a | 238 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
239 | } |
240 | ||
241 | static inline void unix_insert_socket(struct hlist_head *list, struct sock *sk) | |
242 | { | |
fbe9cc4a | 243 | spin_lock(&unix_table_lock); |
1da177e4 | 244 | __unix_insert_socket(list, sk); |
fbe9cc4a | 245 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
246 | } |
247 | ||
097e66c5 DL |
248 | static struct sock *__unix_find_socket_byname(struct net *net, |
249 | struct sockaddr_un *sunname, | |
1da177e4 LT |
250 | int len, int type, unsigned hash) |
251 | { | |
252 | struct sock *s; | |
253 | struct hlist_node *node; | |
254 | ||
255 | sk_for_each(s, node, &unix_socket_table[hash ^ type]) { | |
256 | struct unix_sock *u = unix_sk(s); | |
257 | ||
878628fb | 258 | if (!net_eq(sock_net(s), net)) |
097e66c5 DL |
259 | continue; |
260 | ||
1da177e4 LT |
261 | if (u->addr->len == len && |
262 | !memcmp(u->addr->name, sunname, len)) | |
263 | goto found; | |
264 | } | |
265 | s = NULL; | |
266 | found: | |
267 | return s; | |
268 | } | |
269 | ||
097e66c5 DL |
270 | static inline struct sock *unix_find_socket_byname(struct net *net, |
271 | struct sockaddr_un *sunname, | |
1da177e4 LT |
272 | int len, int type, |
273 | unsigned hash) | |
274 | { | |
275 | struct sock *s; | |
276 | ||
fbe9cc4a | 277 | spin_lock(&unix_table_lock); |
097e66c5 | 278 | s = __unix_find_socket_byname(net, sunname, len, type, hash); |
1da177e4 LT |
279 | if (s) |
280 | sock_hold(s); | |
fbe9cc4a | 281 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
282 | return s; |
283 | } | |
284 | ||
6616f788 | 285 | static struct sock *unix_find_socket_byinode(struct inode *i) |
1da177e4 LT |
286 | { |
287 | struct sock *s; | |
288 | struct hlist_node *node; | |
289 | ||
fbe9cc4a | 290 | spin_lock(&unix_table_lock); |
1da177e4 LT |
291 | sk_for_each(s, node, |
292 | &unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) { | |
293 | struct dentry *dentry = unix_sk(s)->dentry; | |
294 | ||
6eba6a37 | 295 | if (dentry && dentry->d_inode == i) { |
1da177e4 LT |
296 | sock_hold(s); |
297 | goto found; | |
298 | } | |
299 | } | |
300 | s = NULL; | |
301 | found: | |
fbe9cc4a | 302 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
303 | return s; |
304 | } | |
305 | ||
306 | static inline int unix_writable(struct sock *sk) | |
307 | { | |
308 | return (atomic_read(&sk->sk_wmem_alloc) << 2) <= sk->sk_sndbuf; | |
309 | } | |
310 | ||
311 | static void unix_write_space(struct sock *sk) | |
312 | { | |
43815482 ED |
313 | struct socket_wq *wq; |
314 | ||
315 | rcu_read_lock(); | |
1da177e4 | 316 | if (unix_writable(sk)) { |
43815482 ED |
317 | wq = rcu_dereference(sk->sk_wq); |
318 | if (wq_has_sleeper(wq)) | |
67426b75 ED |
319 | wake_up_interruptible_sync_poll(&wq->wait, |
320 | POLLOUT | POLLWRNORM | POLLWRBAND); | |
8d8ad9d7 | 321 | sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); |
1da177e4 | 322 | } |
43815482 | 323 | rcu_read_unlock(); |
1da177e4 LT |
324 | } |
325 | ||
326 | /* When dgram socket disconnects (or changes its peer), we clear its receive | |
327 | * queue of packets arrived from previous peer. First, it allows to do | |
328 | * flow control based only on wmem_alloc; second, sk connected to peer | |
329 | * may receive messages only from that peer. */ | |
330 | static void unix_dgram_disconnected(struct sock *sk, struct sock *other) | |
331 | { | |
b03efcfb | 332 | if (!skb_queue_empty(&sk->sk_receive_queue)) { |
1da177e4 LT |
333 | skb_queue_purge(&sk->sk_receive_queue); |
334 | wake_up_interruptible_all(&unix_sk(sk)->peer_wait); | |
335 | ||
336 | /* If one link of bidirectional dgram pipe is disconnected, | |
337 | * we signal error. Messages are lost. Do not make this, | |
338 | * when peer was not connected to us. | |
339 | */ | |
340 | if (!sock_flag(other, SOCK_DEAD) && unix_peer(other) == sk) { | |
341 | other->sk_err = ECONNRESET; | |
342 | other->sk_error_report(other); | |
343 | } | |
344 | } | |
345 | } | |
346 | ||
347 | static void unix_sock_destructor(struct sock *sk) | |
348 | { | |
349 | struct unix_sock *u = unix_sk(sk); | |
350 | ||
351 | skb_queue_purge(&sk->sk_receive_queue); | |
352 | ||
547b792c IJ |
353 | WARN_ON(atomic_read(&sk->sk_wmem_alloc)); |
354 | WARN_ON(!sk_unhashed(sk)); | |
355 | WARN_ON(sk->sk_socket); | |
1da177e4 | 356 | if (!sock_flag(sk, SOCK_DEAD)) { |
6b41e7dd | 357 | printk(KERN_INFO "Attempt to release alive unix socket: %p\n", sk); |
1da177e4 LT |
358 | return; |
359 | } | |
360 | ||
361 | if (u->addr) | |
362 | unix_release_addr(u->addr); | |
363 | ||
518de9b3 | 364 | atomic_long_dec(&unix_nr_socks); |
6f756a8c | 365 | local_bh_disable(); |
a8076d8d | 366 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); |
6f756a8c | 367 | local_bh_enable(); |
1da177e4 | 368 | #ifdef UNIX_REFCNT_DEBUG |
518de9b3 ED |
369 | printk(KERN_DEBUG "UNIX %p is destroyed, %ld are still alive.\n", sk, |
370 | atomic_long_read(&unix_nr_socks)); | |
1da177e4 LT |
371 | #endif |
372 | } | |
373 | ||
6eba6a37 | 374 | static int unix_release_sock(struct sock *sk, int embrion) |
1da177e4 LT |
375 | { |
376 | struct unix_sock *u = unix_sk(sk); | |
377 | struct dentry *dentry; | |
378 | struct vfsmount *mnt; | |
379 | struct sock *skpair; | |
380 | struct sk_buff *skb; | |
381 | int state; | |
382 | ||
383 | unix_remove_socket(sk); | |
384 | ||
385 | /* Clear state */ | |
1c92b4e5 | 386 | unix_state_lock(sk); |
1da177e4 LT |
387 | sock_orphan(sk); |
388 | sk->sk_shutdown = SHUTDOWN_MASK; | |
389 | dentry = u->dentry; | |
390 | u->dentry = NULL; | |
391 | mnt = u->mnt; | |
392 | u->mnt = NULL; | |
393 | state = sk->sk_state; | |
394 | sk->sk_state = TCP_CLOSE; | |
1c92b4e5 | 395 | unix_state_unlock(sk); |
1da177e4 LT |
396 | |
397 | wake_up_interruptible_all(&u->peer_wait); | |
398 | ||
e27dfcea | 399 | skpair = unix_peer(sk); |
1da177e4 | 400 | |
e27dfcea | 401 | if (skpair != NULL) { |
1da177e4 | 402 | if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) { |
1c92b4e5 | 403 | unix_state_lock(skpair); |
1da177e4 LT |
404 | /* No more writes */ |
405 | skpair->sk_shutdown = SHUTDOWN_MASK; | |
406 | if (!skb_queue_empty(&sk->sk_receive_queue) || embrion) | |
407 | skpair->sk_err = ECONNRESET; | |
1c92b4e5 | 408 | unix_state_unlock(skpair); |
1da177e4 | 409 | skpair->sk_state_change(skpair); |
8d8ad9d7 | 410 | sk_wake_async(skpair, SOCK_WAKE_WAITD, POLL_HUP); |
1da177e4 LT |
411 | } |
412 | sock_put(skpair); /* It may now die */ | |
413 | unix_peer(sk) = NULL; | |
414 | } | |
415 | ||
416 | /* Try to flush out this socket. Throw out buffers at least */ | |
417 | ||
418 | while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) { | |
e27dfcea | 419 | if (state == TCP_LISTEN) |
1da177e4 LT |
420 | unix_release_sock(skb->sk, 1); |
421 | /* passed fds are erased in the kfree_skb hook */ | |
422 | kfree_skb(skb); | |
423 | } | |
424 | ||
425 | if (dentry) { | |
426 | dput(dentry); | |
427 | mntput(mnt); | |
428 | } | |
429 | ||
430 | sock_put(sk); | |
431 | ||
432 | /* ---- Socket is dead now and most probably destroyed ---- */ | |
433 | ||
434 | /* | |
435 | * Fixme: BSD difference: In BSD all sockets connected to use get | |
436 | * ECONNRESET and we die on the spot. In Linux we behave | |
437 | * like files and pipes do and wait for the last | |
438 | * dereference. | |
439 | * | |
440 | * Can't we simply set sock->err? | |
441 | * | |
442 | * What the above comment does talk about? --ANK(980817) | |
443 | */ | |
444 | ||
9305cfa4 | 445 | if (unix_tot_inflight) |
ac7bfa62 | 446 | unix_gc(); /* Garbage collect fds */ |
1da177e4 LT |
447 | |
448 | return 0; | |
449 | } | |
450 | ||
109f6e39 EB |
451 | static void init_peercred(struct sock *sk) |
452 | { | |
453 | put_pid(sk->sk_peer_pid); | |
454 | if (sk->sk_peer_cred) | |
455 | put_cred(sk->sk_peer_cred); | |
456 | sk->sk_peer_pid = get_pid(task_tgid(current)); | |
457 | sk->sk_peer_cred = get_current_cred(); | |
458 | } | |
459 | ||
460 | static void copy_peercred(struct sock *sk, struct sock *peersk) | |
461 | { | |
462 | put_pid(sk->sk_peer_pid); | |
463 | if (sk->sk_peer_cred) | |
464 | put_cred(sk->sk_peer_cred); | |
465 | sk->sk_peer_pid = get_pid(peersk->sk_peer_pid); | |
466 | sk->sk_peer_cred = get_cred(peersk->sk_peer_cred); | |
467 | } | |
468 | ||
1da177e4 LT |
469 | static int unix_listen(struct socket *sock, int backlog) |
470 | { | |
471 | int err; | |
472 | struct sock *sk = sock->sk; | |
473 | struct unix_sock *u = unix_sk(sk); | |
109f6e39 EB |
474 | struct pid *old_pid = NULL; |
475 | const struct cred *old_cred = NULL; | |
1da177e4 LT |
476 | |
477 | err = -EOPNOTSUPP; | |
6eba6a37 ED |
478 | if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET) |
479 | goto out; /* Only stream/seqpacket sockets accept */ | |
1da177e4 LT |
480 | err = -EINVAL; |
481 | if (!u->addr) | |
6eba6a37 | 482 | goto out; /* No listens on an unbound socket */ |
1c92b4e5 | 483 | unix_state_lock(sk); |
1da177e4 LT |
484 | if (sk->sk_state != TCP_CLOSE && sk->sk_state != TCP_LISTEN) |
485 | goto out_unlock; | |
486 | if (backlog > sk->sk_max_ack_backlog) | |
487 | wake_up_interruptible_all(&u->peer_wait); | |
488 | sk->sk_max_ack_backlog = backlog; | |
489 | sk->sk_state = TCP_LISTEN; | |
490 | /* set credentials so connect can copy them */ | |
109f6e39 | 491 | init_peercred(sk); |
1da177e4 LT |
492 | err = 0; |
493 | ||
494 | out_unlock: | |
1c92b4e5 | 495 | unix_state_unlock(sk); |
109f6e39 EB |
496 | put_pid(old_pid); |
497 | if (old_cred) | |
498 | put_cred(old_cred); | |
1da177e4 LT |
499 | out: |
500 | return err; | |
501 | } | |
502 | ||
503 | static int unix_release(struct socket *); | |
504 | static int unix_bind(struct socket *, struct sockaddr *, int); | |
505 | static int unix_stream_connect(struct socket *, struct sockaddr *, | |
506 | int addr_len, int flags); | |
507 | static int unix_socketpair(struct socket *, struct socket *); | |
508 | static int unix_accept(struct socket *, struct socket *, int); | |
509 | static int unix_getname(struct socket *, struct sockaddr *, int *, int); | |
510 | static unsigned int unix_poll(struct file *, struct socket *, poll_table *); | |
ec0d215f RW |
511 | static unsigned int unix_dgram_poll(struct file *, struct socket *, |
512 | poll_table *); | |
1da177e4 LT |
513 | static int unix_ioctl(struct socket *, unsigned int, unsigned long); |
514 | static int unix_shutdown(struct socket *, int); | |
515 | static int unix_stream_sendmsg(struct kiocb *, struct socket *, | |
516 | struct msghdr *, size_t); | |
517 | static int unix_stream_recvmsg(struct kiocb *, struct socket *, | |
518 | struct msghdr *, size_t, int); | |
519 | static int unix_dgram_sendmsg(struct kiocb *, struct socket *, | |
520 | struct msghdr *, size_t); | |
521 | static int unix_dgram_recvmsg(struct kiocb *, struct socket *, | |
522 | struct msghdr *, size_t, int); | |
523 | static int unix_dgram_connect(struct socket *, struct sockaddr *, | |
524 | int, int); | |
525 | static int unix_seqpacket_sendmsg(struct kiocb *, struct socket *, | |
526 | struct msghdr *, size_t); | |
a05d2ad1 EB |
527 | static int unix_seqpacket_recvmsg(struct kiocb *, struct socket *, |
528 | struct msghdr *, size_t, int); | |
1da177e4 | 529 | |
90ddc4f0 | 530 | static const struct proto_ops unix_stream_ops = { |
1da177e4 LT |
531 | .family = PF_UNIX, |
532 | .owner = THIS_MODULE, | |
533 | .release = unix_release, | |
534 | .bind = unix_bind, | |
535 | .connect = unix_stream_connect, | |
536 | .socketpair = unix_socketpair, | |
537 | .accept = unix_accept, | |
538 | .getname = unix_getname, | |
539 | .poll = unix_poll, | |
540 | .ioctl = unix_ioctl, | |
541 | .listen = unix_listen, | |
542 | .shutdown = unix_shutdown, | |
543 | .setsockopt = sock_no_setsockopt, | |
544 | .getsockopt = sock_no_getsockopt, | |
545 | .sendmsg = unix_stream_sendmsg, | |
546 | .recvmsg = unix_stream_recvmsg, | |
547 | .mmap = sock_no_mmap, | |
548 | .sendpage = sock_no_sendpage, | |
549 | }; | |
550 | ||
90ddc4f0 | 551 | static const struct proto_ops unix_dgram_ops = { |
1da177e4 LT |
552 | .family = PF_UNIX, |
553 | .owner = THIS_MODULE, | |
554 | .release = unix_release, | |
555 | .bind = unix_bind, | |
556 | .connect = unix_dgram_connect, | |
557 | .socketpair = unix_socketpair, | |
558 | .accept = sock_no_accept, | |
559 | .getname = unix_getname, | |
ec0d215f | 560 | .poll = unix_dgram_poll, |
1da177e4 LT |
561 | .ioctl = unix_ioctl, |
562 | .listen = sock_no_listen, | |
563 | .shutdown = unix_shutdown, | |
564 | .setsockopt = sock_no_setsockopt, | |
565 | .getsockopt = sock_no_getsockopt, | |
566 | .sendmsg = unix_dgram_sendmsg, | |
567 | .recvmsg = unix_dgram_recvmsg, | |
568 | .mmap = sock_no_mmap, | |
569 | .sendpage = sock_no_sendpage, | |
570 | }; | |
571 | ||
90ddc4f0 | 572 | static const struct proto_ops unix_seqpacket_ops = { |
1da177e4 LT |
573 | .family = PF_UNIX, |
574 | .owner = THIS_MODULE, | |
575 | .release = unix_release, | |
576 | .bind = unix_bind, | |
577 | .connect = unix_stream_connect, | |
578 | .socketpair = unix_socketpair, | |
579 | .accept = unix_accept, | |
580 | .getname = unix_getname, | |
ec0d215f | 581 | .poll = unix_dgram_poll, |
1da177e4 LT |
582 | .ioctl = unix_ioctl, |
583 | .listen = unix_listen, | |
584 | .shutdown = unix_shutdown, | |
585 | .setsockopt = sock_no_setsockopt, | |
586 | .getsockopt = sock_no_getsockopt, | |
587 | .sendmsg = unix_seqpacket_sendmsg, | |
a05d2ad1 | 588 | .recvmsg = unix_seqpacket_recvmsg, |
1da177e4 LT |
589 | .mmap = sock_no_mmap, |
590 | .sendpage = sock_no_sendpage, | |
591 | }; | |
592 | ||
593 | static struct proto unix_proto = { | |
248969ae ED |
594 | .name = "UNIX", |
595 | .owner = THIS_MODULE, | |
248969ae | 596 | .obj_size = sizeof(struct unix_sock), |
1da177e4 LT |
597 | }; |
598 | ||
a09785a2 IM |
599 | /* |
600 | * AF_UNIX sockets do not interact with hardware, hence they | |
601 | * dont trigger interrupts - so it's safe for them to have | |
602 | * bh-unsafe locking for their sk_receive_queue.lock. Split off | |
603 | * this special lock-class by reinitializing the spinlock key: | |
604 | */ | |
605 | static struct lock_class_key af_unix_sk_receive_queue_lock_key; | |
606 | ||
6eba6a37 | 607 | static struct sock *unix_create1(struct net *net, struct socket *sock) |
1da177e4 LT |
608 | { |
609 | struct sock *sk = NULL; | |
610 | struct unix_sock *u; | |
611 | ||
518de9b3 ED |
612 | atomic_long_inc(&unix_nr_socks); |
613 | if (atomic_long_read(&unix_nr_socks) > 2 * get_max_files()) | |
1da177e4 LT |
614 | goto out; |
615 | ||
6257ff21 | 616 | sk = sk_alloc(net, PF_UNIX, GFP_KERNEL, &unix_proto); |
1da177e4 LT |
617 | if (!sk) |
618 | goto out; | |
619 | ||
6eba6a37 | 620 | sock_init_data(sock, sk); |
a09785a2 IM |
621 | lockdep_set_class(&sk->sk_receive_queue.lock, |
622 | &af_unix_sk_receive_queue_lock_key); | |
1da177e4 LT |
623 | |
624 | sk->sk_write_space = unix_write_space; | |
a0a53c8b | 625 | sk->sk_max_ack_backlog = net->unx.sysctl_max_dgram_qlen; |
1da177e4 LT |
626 | sk->sk_destruct = unix_sock_destructor; |
627 | u = unix_sk(sk); | |
628 | u->dentry = NULL; | |
629 | u->mnt = NULL; | |
fd19f329 | 630 | spin_lock_init(&u->lock); |
516e0cc5 | 631 | atomic_long_set(&u->inflight, 0); |
1fd05ba5 | 632 | INIT_LIST_HEAD(&u->link); |
57b47a53 | 633 | mutex_init(&u->readlock); /* single task reading lock */ |
1da177e4 LT |
634 | init_waitqueue_head(&u->peer_wait); |
635 | unix_insert_socket(unix_sockets_unbound, sk); | |
636 | out: | |
284b327b | 637 | if (sk == NULL) |
518de9b3 | 638 | atomic_long_dec(&unix_nr_socks); |
920de804 ED |
639 | else { |
640 | local_bh_disable(); | |
a8076d8d | 641 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); |
920de804 ED |
642 | local_bh_enable(); |
643 | } | |
1da177e4 LT |
644 | return sk; |
645 | } | |
646 | ||
3f378b68 EP |
647 | static int unix_create(struct net *net, struct socket *sock, int protocol, |
648 | int kern) | |
1da177e4 LT |
649 | { |
650 | if (protocol && protocol != PF_UNIX) | |
651 | return -EPROTONOSUPPORT; | |
652 | ||
653 | sock->state = SS_UNCONNECTED; | |
654 | ||
655 | switch (sock->type) { | |
656 | case SOCK_STREAM: | |
657 | sock->ops = &unix_stream_ops; | |
658 | break; | |
659 | /* | |
660 | * Believe it or not BSD has AF_UNIX, SOCK_RAW though | |
661 | * nothing uses it. | |
662 | */ | |
663 | case SOCK_RAW: | |
e27dfcea | 664 | sock->type = SOCK_DGRAM; |
1da177e4 LT |
665 | case SOCK_DGRAM: |
666 | sock->ops = &unix_dgram_ops; | |
667 | break; | |
668 | case SOCK_SEQPACKET: | |
669 | sock->ops = &unix_seqpacket_ops; | |
670 | break; | |
671 | default: | |
672 | return -ESOCKTNOSUPPORT; | |
673 | } | |
674 | ||
1b8d7ae4 | 675 | return unix_create1(net, sock) ? 0 : -ENOMEM; |
1da177e4 LT |
676 | } |
677 | ||
678 | static int unix_release(struct socket *sock) | |
679 | { | |
680 | struct sock *sk = sock->sk; | |
681 | ||
682 | if (!sk) | |
683 | return 0; | |
684 | ||
685 | sock->sk = NULL; | |
686 | ||
6eba6a37 | 687 | return unix_release_sock(sk, 0); |
1da177e4 LT |
688 | } |
689 | ||
690 | static int unix_autobind(struct socket *sock) | |
691 | { | |
692 | struct sock *sk = sock->sk; | |
3b1e0a65 | 693 | struct net *net = sock_net(sk); |
1da177e4 LT |
694 | struct unix_sock *u = unix_sk(sk); |
695 | static u32 ordernum = 1; | |
6eba6a37 | 696 | struct unix_address *addr; |
1da177e4 | 697 | int err; |
8df73ff9 | 698 | unsigned int retries = 0; |
1da177e4 | 699 | |
57b47a53 | 700 | mutex_lock(&u->readlock); |
1da177e4 LT |
701 | |
702 | err = 0; | |
703 | if (u->addr) | |
704 | goto out; | |
705 | ||
706 | err = -ENOMEM; | |
0da974f4 | 707 | addr = kzalloc(sizeof(*addr) + sizeof(short) + 16, GFP_KERNEL); |
1da177e4 LT |
708 | if (!addr) |
709 | goto out; | |
710 | ||
1da177e4 LT |
711 | addr->name->sun_family = AF_UNIX; |
712 | atomic_set(&addr->refcnt, 1); | |
713 | ||
714 | retry: | |
715 | addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + sizeof(short); | |
07f0757a | 716 | addr->hash = unix_hash_fold(csum_partial(addr->name, addr->len, 0)); |
1da177e4 | 717 | |
fbe9cc4a | 718 | spin_lock(&unix_table_lock); |
1da177e4 LT |
719 | ordernum = (ordernum+1)&0xFFFFF; |
720 | ||
097e66c5 | 721 | if (__unix_find_socket_byname(net, addr->name, addr->len, sock->type, |
1da177e4 | 722 | addr->hash)) { |
fbe9cc4a | 723 | spin_unlock(&unix_table_lock); |
8df73ff9 TH |
724 | /* |
725 | * __unix_find_socket_byname() may take long time if many names | |
726 | * are already in use. | |
727 | */ | |
728 | cond_resched(); | |
729 | /* Give up if all names seems to be in use. */ | |
730 | if (retries++ == 0xFFFFF) { | |
731 | err = -ENOSPC; | |
732 | kfree(addr); | |
733 | goto out; | |
734 | } | |
1da177e4 LT |
735 | goto retry; |
736 | } | |
737 | addr->hash ^= sk->sk_type; | |
738 | ||
739 | __unix_remove_socket(sk); | |
740 | u->addr = addr; | |
741 | __unix_insert_socket(&unix_socket_table[addr->hash], sk); | |
fbe9cc4a | 742 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
743 | err = 0; |
744 | ||
57b47a53 | 745 | out: mutex_unlock(&u->readlock); |
1da177e4 LT |
746 | return err; |
747 | } | |
748 | ||
097e66c5 DL |
749 | static struct sock *unix_find_other(struct net *net, |
750 | struct sockaddr_un *sunname, int len, | |
1da177e4 LT |
751 | int type, unsigned hash, int *error) |
752 | { | |
753 | struct sock *u; | |
421748ec | 754 | struct path path; |
1da177e4 | 755 | int err = 0; |
ac7bfa62 | 756 | |
1da177e4 | 757 | if (sunname->sun_path[0]) { |
421748ec AV |
758 | struct inode *inode; |
759 | err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, &path); | |
1da177e4 LT |
760 | if (err) |
761 | goto fail; | |
421748ec AV |
762 | inode = path.dentry->d_inode; |
763 | err = inode_permission(inode, MAY_WRITE); | |
1da177e4 LT |
764 | if (err) |
765 | goto put_fail; | |
766 | ||
767 | err = -ECONNREFUSED; | |
421748ec | 768 | if (!S_ISSOCK(inode->i_mode)) |
1da177e4 | 769 | goto put_fail; |
6616f788 | 770 | u = unix_find_socket_byinode(inode); |
1da177e4 LT |
771 | if (!u) |
772 | goto put_fail; | |
773 | ||
774 | if (u->sk_type == type) | |
421748ec | 775 | touch_atime(path.mnt, path.dentry); |
1da177e4 | 776 | |
421748ec | 777 | path_put(&path); |
1da177e4 | 778 | |
e27dfcea | 779 | err = -EPROTOTYPE; |
1da177e4 LT |
780 | if (u->sk_type != type) { |
781 | sock_put(u); | |
782 | goto fail; | |
783 | } | |
784 | } else { | |
785 | err = -ECONNREFUSED; | |
e27dfcea | 786 | u = unix_find_socket_byname(net, sunname, len, type, hash); |
1da177e4 LT |
787 | if (u) { |
788 | struct dentry *dentry; | |
789 | dentry = unix_sk(u)->dentry; | |
790 | if (dentry) | |
791 | touch_atime(unix_sk(u)->mnt, dentry); | |
792 | } else | |
793 | goto fail; | |
794 | } | |
795 | return u; | |
796 | ||
797 | put_fail: | |
421748ec | 798 | path_put(&path); |
1da177e4 | 799 | fail: |
e27dfcea | 800 | *error = err; |
1da177e4 LT |
801 | return NULL; |
802 | } | |
803 | ||
804 | ||
805 | static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) | |
806 | { | |
807 | struct sock *sk = sock->sk; | |
3b1e0a65 | 808 | struct net *net = sock_net(sk); |
1da177e4 | 809 | struct unix_sock *u = unix_sk(sk); |
e27dfcea | 810 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr; |
6eba6a37 | 811 | struct dentry *dentry = NULL; |
1da177e4 LT |
812 | struct nameidata nd; |
813 | int err; | |
814 | unsigned hash; | |
815 | struct unix_address *addr; | |
816 | struct hlist_head *list; | |
817 | ||
818 | err = -EINVAL; | |
819 | if (sunaddr->sun_family != AF_UNIX) | |
820 | goto out; | |
821 | ||
e27dfcea | 822 | if (addr_len == sizeof(short)) { |
1da177e4 LT |
823 | err = unix_autobind(sock); |
824 | goto out; | |
825 | } | |
826 | ||
827 | err = unix_mkname(sunaddr, addr_len, &hash); | |
828 | if (err < 0) | |
829 | goto out; | |
830 | addr_len = err; | |
831 | ||
57b47a53 | 832 | mutex_lock(&u->readlock); |
1da177e4 LT |
833 | |
834 | err = -EINVAL; | |
835 | if (u->addr) | |
836 | goto out_up; | |
837 | ||
838 | err = -ENOMEM; | |
839 | addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL); | |
840 | if (!addr) | |
841 | goto out_up; | |
842 | ||
843 | memcpy(addr->name, sunaddr, addr_len); | |
844 | addr->len = addr_len; | |
845 | addr->hash = hash ^ sk->sk_type; | |
846 | atomic_set(&addr->refcnt, 1); | |
847 | ||
848 | if (sunaddr->sun_path[0]) { | |
849 | unsigned int mode; | |
850 | err = 0; | |
851 | /* | |
852 | * Get the parent directory, calculate the hash for last | |
853 | * component. | |
854 | */ | |
c9c6cac0 | 855 | err = kern_path_parent(sunaddr->sun_path, &nd); |
1da177e4 LT |
856 | if (err) |
857 | goto out_mknod_parent; | |
f81a0bff CH |
858 | |
859 | dentry = lookup_create(&nd, 0); | |
1da177e4 LT |
860 | err = PTR_ERR(dentry); |
861 | if (IS_ERR(dentry)) | |
862 | goto out_mknod_unlock; | |
f81a0bff | 863 | |
1da177e4 LT |
864 | /* |
865 | * All right, let's create it. | |
866 | */ | |
867 | mode = S_IFSOCK | | |
ce3b0f8d | 868 | (SOCK_INODE(sock)->i_mode & ~current_umask()); |
463c3197 DH |
869 | err = mnt_want_write(nd.path.mnt); |
870 | if (err) | |
871 | goto out_mknod_dput; | |
be6d3e56 KT |
872 | err = security_path_mknod(&nd.path, dentry, mode, 0); |
873 | if (err) | |
874 | goto out_mknod_drop_write; | |
4ac91378 | 875 | err = vfs_mknod(nd.path.dentry->d_inode, dentry, mode, 0); |
be6d3e56 | 876 | out_mknod_drop_write: |
463c3197 | 877 | mnt_drop_write(nd.path.mnt); |
1da177e4 LT |
878 | if (err) |
879 | goto out_mknod_dput; | |
4ac91378 JB |
880 | mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
881 | dput(nd.path.dentry); | |
882 | nd.path.dentry = dentry; | |
1da177e4 LT |
883 | |
884 | addr->hash = UNIX_HASH_SIZE; | |
885 | } | |
886 | ||
fbe9cc4a | 887 | spin_lock(&unix_table_lock); |
1da177e4 LT |
888 | |
889 | if (!sunaddr->sun_path[0]) { | |
890 | err = -EADDRINUSE; | |
097e66c5 | 891 | if (__unix_find_socket_byname(net, sunaddr, addr_len, |
1da177e4 LT |
892 | sk->sk_type, hash)) { |
893 | unix_release_addr(addr); | |
894 | goto out_unlock; | |
895 | } | |
896 | ||
897 | list = &unix_socket_table[addr->hash]; | |
898 | } else { | |
899 | list = &unix_socket_table[dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1)]; | |
4ac91378 JB |
900 | u->dentry = nd.path.dentry; |
901 | u->mnt = nd.path.mnt; | |
1da177e4 LT |
902 | } |
903 | ||
904 | err = 0; | |
905 | __unix_remove_socket(sk); | |
906 | u->addr = addr; | |
907 | __unix_insert_socket(list, sk); | |
908 | ||
909 | out_unlock: | |
fbe9cc4a | 910 | spin_unlock(&unix_table_lock); |
1da177e4 | 911 | out_up: |
57b47a53 | 912 | mutex_unlock(&u->readlock); |
1da177e4 LT |
913 | out: |
914 | return err; | |
915 | ||
916 | out_mknod_dput: | |
917 | dput(dentry); | |
918 | out_mknod_unlock: | |
4ac91378 | 919 | mutex_unlock(&nd.path.dentry->d_inode->i_mutex); |
1d957f9b | 920 | path_put(&nd.path); |
1da177e4 | 921 | out_mknod_parent: |
e27dfcea JK |
922 | if (err == -EEXIST) |
923 | err = -EADDRINUSE; | |
1da177e4 LT |
924 | unix_release_addr(addr); |
925 | goto out_up; | |
926 | } | |
927 | ||
278a3de5 DM |
928 | static void unix_state_double_lock(struct sock *sk1, struct sock *sk2) |
929 | { | |
930 | if (unlikely(sk1 == sk2) || !sk2) { | |
931 | unix_state_lock(sk1); | |
932 | return; | |
933 | } | |
934 | if (sk1 < sk2) { | |
935 | unix_state_lock(sk1); | |
936 | unix_state_lock_nested(sk2); | |
937 | } else { | |
938 | unix_state_lock(sk2); | |
939 | unix_state_lock_nested(sk1); | |
940 | } | |
941 | } | |
942 | ||
943 | static void unix_state_double_unlock(struct sock *sk1, struct sock *sk2) | |
944 | { | |
945 | if (unlikely(sk1 == sk2) || !sk2) { | |
946 | unix_state_unlock(sk1); | |
947 | return; | |
948 | } | |
949 | unix_state_unlock(sk1); | |
950 | unix_state_unlock(sk2); | |
951 | } | |
952 | ||
1da177e4 LT |
953 | static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr, |
954 | int alen, int flags) | |
955 | { | |
956 | struct sock *sk = sock->sk; | |
3b1e0a65 | 957 | struct net *net = sock_net(sk); |
e27dfcea | 958 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)addr; |
1da177e4 LT |
959 | struct sock *other; |
960 | unsigned hash; | |
961 | int err; | |
962 | ||
963 | if (addr->sa_family != AF_UNSPEC) { | |
964 | err = unix_mkname(sunaddr, alen, &hash); | |
965 | if (err < 0) | |
966 | goto out; | |
967 | alen = err; | |
968 | ||
969 | if (test_bit(SOCK_PASSCRED, &sock->flags) && | |
970 | !unix_sk(sk)->addr && (err = unix_autobind(sock)) != 0) | |
971 | goto out; | |
972 | ||
278a3de5 | 973 | restart: |
e27dfcea | 974 | other = unix_find_other(net, sunaddr, alen, sock->type, hash, &err); |
1da177e4 LT |
975 | if (!other) |
976 | goto out; | |
977 | ||
278a3de5 DM |
978 | unix_state_double_lock(sk, other); |
979 | ||
980 | /* Apparently VFS overslept socket death. Retry. */ | |
981 | if (sock_flag(other, SOCK_DEAD)) { | |
982 | unix_state_double_unlock(sk, other); | |
983 | sock_put(other); | |
984 | goto restart; | |
985 | } | |
1da177e4 LT |
986 | |
987 | err = -EPERM; | |
988 | if (!unix_may_send(sk, other)) | |
989 | goto out_unlock; | |
990 | ||
991 | err = security_unix_may_send(sk->sk_socket, other->sk_socket); | |
992 | if (err) | |
993 | goto out_unlock; | |
994 | ||
995 | } else { | |
996 | /* | |
997 | * 1003.1g breaking connected state with AF_UNSPEC | |
998 | */ | |
999 | other = NULL; | |
278a3de5 | 1000 | unix_state_double_lock(sk, other); |
1da177e4 LT |
1001 | } |
1002 | ||
1003 | /* | |
1004 | * If it was connected, reconnect. | |
1005 | */ | |
1006 | if (unix_peer(sk)) { | |
1007 | struct sock *old_peer = unix_peer(sk); | |
e27dfcea | 1008 | unix_peer(sk) = other; |
278a3de5 | 1009 | unix_state_double_unlock(sk, other); |
1da177e4 LT |
1010 | |
1011 | if (other != old_peer) | |
1012 | unix_dgram_disconnected(sk, old_peer); | |
1013 | sock_put(old_peer); | |
1014 | } else { | |
e27dfcea | 1015 | unix_peer(sk) = other; |
278a3de5 | 1016 | unix_state_double_unlock(sk, other); |
1da177e4 | 1017 | } |
ac7bfa62 | 1018 | return 0; |
1da177e4 LT |
1019 | |
1020 | out_unlock: | |
278a3de5 | 1021 | unix_state_double_unlock(sk, other); |
1da177e4 LT |
1022 | sock_put(other); |
1023 | out: | |
1024 | return err; | |
1025 | } | |
1026 | ||
1027 | static long unix_wait_for_peer(struct sock *other, long timeo) | |
1028 | { | |
1029 | struct unix_sock *u = unix_sk(other); | |
1030 | int sched; | |
1031 | DEFINE_WAIT(wait); | |
1032 | ||
1033 | prepare_to_wait_exclusive(&u->peer_wait, &wait, TASK_INTERRUPTIBLE); | |
1034 | ||
1035 | sched = !sock_flag(other, SOCK_DEAD) && | |
1036 | !(other->sk_shutdown & RCV_SHUTDOWN) && | |
3c73419c | 1037 | unix_recvq_full(other); |
1da177e4 | 1038 | |
1c92b4e5 | 1039 | unix_state_unlock(other); |
1da177e4 LT |
1040 | |
1041 | if (sched) | |
1042 | timeo = schedule_timeout(timeo); | |
1043 | ||
1044 | finish_wait(&u->peer_wait, &wait); | |
1045 | return timeo; | |
1046 | } | |
1047 | ||
1048 | static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr, | |
1049 | int addr_len, int flags) | |
1050 | { | |
e27dfcea | 1051 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr; |
1da177e4 | 1052 | struct sock *sk = sock->sk; |
3b1e0a65 | 1053 | struct net *net = sock_net(sk); |
1da177e4 LT |
1054 | struct unix_sock *u = unix_sk(sk), *newu, *otheru; |
1055 | struct sock *newsk = NULL; | |
1056 | struct sock *other = NULL; | |
1057 | struct sk_buff *skb = NULL; | |
1058 | unsigned hash; | |
1059 | int st; | |
1060 | int err; | |
1061 | long timeo; | |
1062 | ||
1063 | err = unix_mkname(sunaddr, addr_len, &hash); | |
1064 | if (err < 0) | |
1065 | goto out; | |
1066 | addr_len = err; | |
1067 | ||
f64f9e71 JP |
1068 | if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr && |
1069 | (err = unix_autobind(sock)) != 0) | |
1da177e4 LT |
1070 | goto out; |
1071 | ||
1072 | timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); | |
1073 | ||
1074 | /* First of all allocate resources. | |
1075 | If we will make it after state is locked, | |
1076 | we will have to recheck all again in any case. | |
1077 | */ | |
1078 | ||
1079 | err = -ENOMEM; | |
1080 | ||
1081 | /* create new sock for complete connection */ | |
3b1e0a65 | 1082 | newsk = unix_create1(sock_net(sk), NULL); |
1da177e4 LT |
1083 | if (newsk == NULL) |
1084 | goto out; | |
1085 | ||
1086 | /* Allocate skb for sending to listening sock */ | |
1087 | skb = sock_wmalloc(newsk, 1, 0, GFP_KERNEL); | |
1088 | if (skb == NULL) | |
1089 | goto out; | |
1090 | ||
1091 | restart: | |
1092 | /* Find listening sock. */ | |
097e66c5 | 1093 | other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, hash, &err); |
1da177e4 LT |
1094 | if (!other) |
1095 | goto out; | |
1096 | ||
1097 | /* Latch state of peer */ | |
1c92b4e5 | 1098 | unix_state_lock(other); |
1da177e4 LT |
1099 | |
1100 | /* Apparently VFS overslept socket death. Retry. */ | |
1101 | if (sock_flag(other, SOCK_DEAD)) { | |
1c92b4e5 | 1102 | unix_state_unlock(other); |
1da177e4 LT |
1103 | sock_put(other); |
1104 | goto restart; | |
1105 | } | |
1106 | ||
1107 | err = -ECONNREFUSED; | |
1108 | if (other->sk_state != TCP_LISTEN) | |
1109 | goto out_unlock; | |
77238f2b TS |
1110 | if (other->sk_shutdown & RCV_SHUTDOWN) |
1111 | goto out_unlock; | |
1da177e4 | 1112 | |
3c73419c | 1113 | if (unix_recvq_full(other)) { |
1da177e4 LT |
1114 | err = -EAGAIN; |
1115 | if (!timeo) | |
1116 | goto out_unlock; | |
1117 | ||
1118 | timeo = unix_wait_for_peer(other, timeo); | |
1119 | ||
1120 | err = sock_intr_errno(timeo); | |
1121 | if (signal_pending(current)) | |
1122 | goto out; | |
1123 | sock_put(other); | |
1124 | goto restart; | |
ac7bfa62 | 1125 | } |
1da177e4 LT |
1126 | |
1127 | /* Latch our state. | |
1128 | ||
e5537bfc | 1129 | It is tricky place. We need to grab our state lock and cannot |
1da177e4 LT |
1130 | drop lock on peer. It is dangerous because deadlock is |
1131 | possible. Connect to self case and simultaneous | |
1132 | attempt to connect are eliminated by checking socket | |
1133 | state. other is TCP_LISTEN, if sk is TCP_LISTEN we | |
1134 | check this before attempt to grab lock. | |
1135 | ||
1136 | Well, and we have to recheck the state after socket locked. | |
1137 | */ | |
1138 | st = sk->sk_state; | |
1139 | ||
1140 | switch (st) { | |
1141 | case TCP_CLOSE: | |
1142 | /* This is ok... continue with connect */ | |
1143 | break; | |
1144 | case TCP_ESTABLISHED: | |
1145 | /* Socket is already connected */ | |
1146 | err = -EISCONN; | |
1147 | goto out_unlock; | |
1148 | default: | |
1149 | err = -EINVAL; | |
1150 | goto out_unlock; | |
1151 | } | |
1152 | ||
1c92b4e5 | 1153 | unix_state_lock_nested(sk); |
1da177e4 LT |
1154 | |
1155 | if (sk->sk_state != st) { | |
1c92b4e5 DM |
1156 | unix_state_unlock(sk); |
1157 | unix_state_unlock(other); | |
1da177e4 LT |
1158 | sock_put(other); |
1159 | goto restart; | |
1160 | } | |
1161 | ||
3610cda5 | 1162 | err = security_unix_stream_connect(sk, other, newsk); |
1da177e4 | 1163 | if (err) { |
1c92b4e5 | 1164 | unix_state_unlock(sk); |
1da177e4 LT |
1165 | goto out_unlock; |
1166 | } | |
1167 | ||
1168 | /* The way is open! Fastly set all the necessary fields... */ | |
1169 | ||
1170 | sock_hold(sk); | |
1171 | unix_peer(newsk) = sk; | |
1172 | newsk->sk_state = TCP_ESTABLISHED; | |
1173 | newsk->sk_type = sk->sk_type; | |
109f6e39 | 1174 | init_peercred(newsk); |
1da177e4 | 1175 | newu = unix_sk(newsk); |
eaefd110 | 1176 | RCU_INIT_POINTER(newsk->sk_wq, &newu->peer_wq); |
1da177e4 LT |
1177 | otheru = unix_sk(other); |
1178 | ||
1179 | /* copy address information from listening to new sock*/ | |
1180 | if (otheru->addr) { | |
1181 | atomic_inc(&otheru->addr->refcnt); | |
1182 | newu->addr = otheru->addr; | |
1183 | } | |
1184 | if (otheru->dentry) { | |
1185 | newu->dentry = dget(otheru->dentry); | |
1186 | newu->mnt = mntget(otheru->mnt); | |
1187 | } | |
1188 | ||
1189 | /* Set credentials */ | |
109f6e39 | 1190 | copy_peercred(sk, other); |
1da177e4 | 1191 | |
1da177e4 LT |
1192 | sock->state = SS_CONNECTED; |
1193 | sk->sk_state = TCP_ESTABLISHED; | |
830a1e5c BL |
1194 | sock_hold(newsk); |
1195 | ||
1196 | smp_mb__after_atomic_inc(); /* sock_hold() does an atomic_inc() */ | |
1197 | unix_peer(sk) = newsk; | |
1da177e4 | 1198 | |
1c92b4e5 | 1199 | unix_state_unlock(sk); |
1da177e4 LT |
1200 | |
1201 | /* take ten and and send info to listening sock */ | |
1202 | spin_lock(&other->sk_receive_queue.lock); | |
1203 | __skb_queue_tail(&other->sk_receive_queue, skb); | |
1da177e4 | 1204 | spin_unlock(&other->sk_receive_queue.lock); |
1c92b4e5 | 1205 | unix_state_unlock(other); |
1da177e4 LT |
1206 | other->sk_data_ready(other, 0); |
1207 | sock_put(other); | |
1208 | return 0; | |
1209 | ||
1210 | out_unlock: | |
1211 | if (other) | |
1c92b4e5 | 1212 | unix_state_unlock(other); |
1da177e4 LT |
1213 | |
1214 | out: | |
40d44446 | 1215 | kfree_skb(skb); |
1da177e4 LT |
1216 | if (newsk) |
1217 | unix_release_sock(newsk, 0); | |
1218 | if (other) | |
1219 | sock_put(other); | |
1220 | return err; | |
1221 | } | |
1222 | ||
1223 | static int unix_socketpair(struct socket *socka, struct socket *sockb) | |
1224 | { | |
e27dfcea | 1225 | struct sock *ska = socka->sk, *skb = sockb->sk; |
1da177e4 LT |
1226 | |
1227 | /* Join our sockets back to back */ | |
1228 | sock_hold(ska); | |
1229 | sock_hold(skb); | |
e27dfcea JK |
1230 | unix_peer(ska) = skb; |
1231 | unix_peer(skb) = ska; | |
109f6e39 EB |
1232 | init_peercred(ska); |
1233 | init_peercred(skb); | |
1da177e4 LT |
1234 | |
1235 | if (ska->sk_type != SOCK_DGRAM) { | |
1236 | ska->sk_state = TCP_ESTABLISHED; | |
1237 | skb->sk_state = TCP_ESTABLISHED; | |
1238 | socka->state = SS_CONNECTED; | |
1239 | sockb->state = SS_CONNECTED; | |
1240 | } | |
1241 | return 0; | |
1242 | } | |
1243 | ||
1244 | static int unix_accept(struct socket *sock, struct socket *newsock, int flags) | |
1245 | { | |
1246 | struct sock *sk = sock->sk; | |
1247 | struct sock *tsk; | |
1248 | struct sk_buff *skb; | |
1249 | int err; | |
1250 | ||
1251 | err = -EOPNOTSUPP; | |
6eba6a37 | 1252 | if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET) |
1da177e4 LT |
1253 | goto out; |
1254 | ||
1255 | err = -EINVAL; | |
1256 | if (sk->sk_state != TCP_LISTEN) | |
1257 | goto out; | |
1258 | ||
1259 | /* If socket state is TCP_LISTEN it cannot change (for now...), | |
1260 | * so that no locks are necessary. | |
1261 | */ | |
1262 | ||
1263 | skb = skb_recv_datagram(sk, 0, flags&O_NONBLOCK, &err); | |
1264 | if (!skb) { | |
1265 | /* This means receive shutdown. */ | |
1266 | if (err == 0) | |
1267 | err = -EINVAL; | |
1268 | goto out; | |
1269 | } | |
1270 | ||
1271 | tsk = skb->sk; | |
1272 | skb_free_datagram(sk, skb); | |
1273 | wake_up_interruptible(&unix_sk(sk)->peer_wait); | |
1274 | ||
1275 | /* attach accepted sock to socket */ | |
1c92b4e5 | 1276 | unix_state_lock(tsk); |
1da177e4 LT |
1277 | newsock->state = SS_CONNECTED; |
1278 | sock_graft(tsk, newsock); | |
1c92b4e5 | 1279 | unix_state_unlock(tsk); |
1da177e4 LT |
1280 | return 0; |
1281 | ||
1282 | out: | |
1283 | return err; | |
1284 | } | |
1285 | ||
1286 | ||
1287 | static int unix_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len, int peer) | |
1288 | { | |
1289 | struct sock *sk = sock->sk; | |
1290 | struct unix_sock *u; | |
13cfa97b | 1291 | DECLARE_SOCKADDR(struct sockaddr_un *, sunaddr, uaddr); |
1da177e4 LT |
1292 | int err = 0; |
1293 | ||
1294 | if (peer) { | |
1295 | sk = unix_peer_get(sk); | |
1296 | ||
1297 | err = -ENOTCONN; | |
1298 | if (!sk) | |
1299 | goto out; | |
1300 | err = 0; | |
1301 | } else { | |
1302 | sock_hold(sk); | |
1303 | } | |
1304 | ||
1305 | u = unix_sk(sk); | |
1c92b4e5 | 1306 | unix_state_lock(sk); |
1da177e4 LT |
1307 | if (!u->addr) { |
1308 | sunaddr->sun_family = AF_UNIX; | |
1309 | sunaddr->sun_path[0] = 0; | |
1310 | *uaddr_len = sizeof(short); | |
1311 | } else { | |
1312 | struct unix_address *addr = u->addr; | |
1313 | ||
1314 | *uaddr_len = addr->len; | |
1315 | memcpy(sunaddr, addr->name, *uaddr_len); | |
1316 | } | |
1c92b4e5 | 1317 | unix_state_unlock(sk); |
1da177e4 LT |
1318 | sock_put(sk); |
1319 | out: | |
1320 | return err; | |
1321 | } | |
1322 | ||
1323 | static void unix_detach_fds(struct scm_cookie *scm, struct sk_buff *skb) | |
1324 | { | |
1325 | int i; | |
1326 | ||
1327 | scm->fp = UNIXCB(skb).fp; | |
1da177e4 LT |
1328 | UNIXCB(skb).fp = NULL; |
1329 | ||
6eba6a37 | 1330 | for (i = scm->fp->count-1; i >= 0; i--) |
1da177e4 LT |
1331 | unix_notinflight(scm->fp->fp[i]); |
1332 | } | |
1333 | ||
7361c36c | 1334 | static void unix_destruct_scm(struct sk_buff *skb) |
1da177e4 LT |
1335 | { |
1336 | struct scm_cookie scm; | |
1337 | memset(&scm, 0, sizeof(scm)); | |
7361c36c EB |
1338 | scm.pid = UNIXCB(skb).pid; |
1339 | scm.cred = UNIXCB(skb).cred; | |
1340 | if (UNIXCB(skb).fp) | |
1341 | unix_detach_fds(&scm, skb); | |
1da177e4 LT |
1342 | |
1343 | /* Alas, it calls VFS */ | |
1344 | /* So fscking what? fput() had been SMP-safe since the last Summer */ | |
1345 | scm_destroy(&scm); | |
1346 | sock_wfree(skb); | |
1347 | } | |
1348 | ||
25888e30 ED |
1349 | #define MAX_RECURSION_LEVEL 4 |
1350 | ||
6209344f | 1351 | static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb) |
1da177e4 LT |
1352 | { |
1353 | int i; | |
25888e30 ED |
1354 | unsigned char max_level = 0; |
1355 | int unix_sock_count = 0; | |
1356 | ||
1357 | for (i = scm->fp->count - 1; i >= 0; i--) { | |
1358 | struct sock *sk = unix_get_socket(scm->fp->fp[i]); | |
1359 | ||
1360 | if (sk) { | |
1361 | unix_sock_count++; | |
1362 | max_level = max(max_level, | |
1363 | unix_sk(sk)->recursion_level); | |
1364 | } | |
1365 | } | |
1366 | if (unlikely(max_level > MAX_RECURSION_LEVEL)) | |
1367 | return -ETOOMANYREFS; | |
6209344f MS |
1368 | |
1369 | /* | |
1370 | * Need to duplicate file references for the sake of garbage | |
1371 | * collection. Otherwise a socket in the fps might become a | |
1372 | * candidate for GC while the skb is not yet queued. | |
1373 | */ | |
1374 | UNIXCB(skb).fp = scm_fp_dup(scm->fp); | |
1375 | if (!UNIXCB(skb).fp) | |
1376 | return -ENOMEM; | |
1377 | ||
25888e30 ED |
1378 | if (unix_sock_count) { |
1379 | for (i = scm->fp->count - 1; i >= 0; i--) | |
1380 | unix_inflight(scm->fp->fp[i]); | |
1381 | } | |
1382 | return max_level; | |
1da177e4 LT |
1383 | } |
1384 | ||
7361c36c EB |
1385 | static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool send_fds) |
1386 | { | |
1387 | int err = 0; | |
1388 | UNIXCB(skb).pid = get_pid(scm->pid); | |
1389 | UNIXCB(skb).cred = get_cred(scm->cred); | |
1390 | UNIXCB(skb).fp = NULL; | |
1391 | if (scm->fp && send_fds) | |
1392 | err = unix_attach_fds(scm, skb); | |
1393 | ||
1394 | skb->destructor = unix_destruct_scm; | |
1395 | return err; | |
1396 | } | |
1397 | ||
1da177e4 LT |
1398 | /* |
1399 | * Send AF_UNIX data. | |
1400 | */ | |
1401 | ||
1402 | static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, | |
1403 | struct msghdr *msg, size_t len) | |
1404 | { | |
1405 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1406 | struct sock *sk = sock->sk; | |
3b1e0a65 | 1407 | struct net *net = sock_net(sk); |
1da177e4 | 1408 | struct unix_sock *u = unix_sk(sk); |
e27dfcea | 1409 | struct sockaddr_un *sunaddr = msg->msg_name; |
1da177e4 LT |
1410 | struct sock *other = NULL; |
1411 | int namelen = 0; /* fake GCC */ | |
1412 | int err; | |
1413 | unsigned hash; | |
1414 | struct sk_buff *skb; | |
1415 | long timeo; | |
1416 | struct scm_cookie tmp_scm; | |
25888e30 | 1417 | int max_level; |
1da177e4 LT |
1418 | |
1419 | if (NULL == siocb->scm) | |
1420 | siocb->scm = &tmp_scm; | |
5f23b734 | 1421 | wait_for_unix_gc(); |
1da177e4 LT |
1422 | err = scm_send(sock, msg, siocb->scm); |
1423 | if (err < 0) | |
1424 | return err; | |
1425 | ||
1426 | err = -EOPNOTSUPP; | |
1427 | if (msg->msg_flags&MSG_OOB) | |
1428 | goto out; | |
1429 | ||
1430 | if (msg->msg_namelen) { | |
1431 | err = unix_mkname(sunaddr, msg->msg_namelen, &hash); | |
1432 | if (err < 0) | |
1433 | goto out; | |
1434 | namelen = err; | |
1435 | } else { | |
1436 | sunaddr = NULL; | |
1437 | err = -ENOTCONN; | |
1438 | other = unix_peer_get(sk); | |
1439 | if (!other) | |
1440 | goto out; | |
1441 | } | |
1442 | ||
f64f9e71 JP |
1443 | if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr |
1444 | && (err = unix_autobind(sock)) != 0) | |
1da177e4 LT |
1445 | goto out; |
1446 | ||
1447 | err = -EMSGSIZE; | |
1448 | if (len > sk->sk_sndbuf - 32) | |
1449 | goto out; | |
1450 | ||
1451 | skb = sock_alloc_send_skb(sk, len, msg->msg_flags&MSG_DONTWAIT, &err); | |
e27dfcea | 1452 | if (skb == NULL) |
1da177e4 LT |
1453 | goto out; |
1454 | ||
7361c36c | 1455 | err = unix_scm_to_skb(siocb->scm, skb, true); |
25888e30 | 1456 | if (err < 0) |
7361c36c | 1457 | goto out_free; |
25888e30 | 1458 | max_level = err + 1; |
dc49c1f9 | 1459 | unix_get_secdata(siocb->scm, skb); |
877ce7c1 | 1460 | |
badff6d0 | 1461 | skb_reset_transport_header(skb); |
6eba6a37 | 1462 | err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); |
1da177e4 LT |
1463 | if (err) |
1464 | goto out_free; | |
1465 | ||
1466 | timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); | |
1467 | ||
1468 | restart: | |
1469 | if (!other) { | |
1470 | err = -ECONNRESET; | |
1471 | if (sunaddr == NULL) | |
1472 | goto out_free; | |
1473 | ||
097e66c5 | 1474 | other = unix_find_other(net, sunaddr, namelen, sk->sk_type, |
1da177e4 | 1475 | hash, &err); |
e27dfcea | 1476 | if (other == NULL) |
1da177e4 LT |
1477 | goto out_free; |
1478 | } | |
1479 | ||
d6ae3bae AC |
1480 | if (sk_filter(other, skb) < 0) { |
1481 | /* Toss the packet but do not return any error to the sender */ | |
1482 | err = len; | |
1483 | goto out_free; | |
1484 | } | |
1485 | ||
1c92b4e5 | 1486 | unix_state_lock(other); |
1da177e4 LT |
1487 | err = -EPERM; |
1488 | if (!unix_may_send(sk, other)) | |
1489 | goto out_unlock; | |
1490 | ||
1491 | if (sock_flag(other, SOCK_DEAD)) { | |
1492 | /* | |
1493 | * Check with 1003.1g - what should | |
1494 | * datagram error | |
1495 | */ | |
1c92b4e5 | 1496 | unix_state_unlock(other); |
1da177e4 LT |
1497 | sock_put(other); |
1498 | ||
1499 | err = 0; | |
1c92b4e5 | 1500 | unix_state_lock(sk); |
1da177e4 | 1501 | if (unix_peer(sk) == other) { |
e27dfcea | 1502 | unix_peer(sk) = NULL; |
1c92b4e5 | 1503 | unix_state_unlock(sk); |
1da177e4 LT |
1504 | |
1505 | unix_dgram_disconnected(sk, other); | |
1506 | sock_put(other); | |
1507 | err = -ECONNREFUSED; | |
1508 | } else { | |
1c92b4e5 | 1509 | unix_state_unlock(sk); |
1da177e4 LT |
1510 | } |
1511 | ||
1512 | other = NULL; | |
1513 | if (err) | |
1514 | goto out_free; | |
1515 | goto restart; | |
1516 | } | |
1517 | ||
1518 | err = -EPIPE; | |
1519 | if (other->sk_shutdown & RCV_SHUTDOWN) | |
1520 | goto out_unlock; | |
1521 | ||
1522 | if (sk->sk_type != SOCK_SEQPACKET) { | |
1523 | err = security_unix_may_send(sk->sk_socket, other->sk_socket); | |
1524 | if (err) | |
1525 | goto out_unlock; | |
1526 | } | |
1527 | ||
3c73419c | 1528 | if (unix_peer(other) != sk && unix_recvq_full(other)) { |
1da177e4 LT |
1529 | if (!timeo) { |
1530 | err = -EAGAIN; | |
1531 | goto out_unlock; | |
1532 | } | |
1533 | ||
1534 | timeo = unix_wait_for_peer(other, timeo); | |
1535 | ||
1536 | err = sock_intr_errno(timeo); | |
1537 | if (signal_pending(current)) | |
1538 | goto out_free; | |
1539 | ||
1540 | goto restart; | |
1541 | } | |
1542 | ||
3f66116e AC |
1543 | if (sock_flag(other, SOCK_RCVTSTAMP)) |
1544 | __net_timestamp(skb); | |
1da177e4 | 1545 | skb_queue_tail(&other->sk_receive_queue, skb); |
25888e30 ED |
1546 | if (max_level > unix_sk(other)->recursion_level) |
1547 | unix_sk(other)->recursion_level = max_level; | |
1c92b4e5 | 1548 | unix_state_unlock(other); |
1da177e4 LT |
1549 | other->sk_data_ready(other, len); |
1550 | sock_put(other); | |
1551 | scm_destroy(siocb->scm); | |
1552 | return len; | |
1553 | ||
1554 | out_unlock: | |
1c92b4e5 | 1555 | unix_state_unlock(other); |
1da177e4 LT |
1556 | out_free: |
1557 | kfree_skb(skb); | |
1558 | out: | |
1559 | if (other) | |
1560 | sock_put(other); | |
1561 | scm_destroy(siocb->scm); | |
1562 | return err; | |
1563 | } | |
1564 | ||
ac7bfa62 | 1565 | |
1da177e4 LT |
1566 | static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, |
1567 | struct msghdr *msg, size_t len) | |
1568 | { | |
1569 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1570 | struct sock *sk = sock->sk; | |
1571 | struct sock *other = NULL; | |
6eba6a37 | 1572 | int err, size; |
1da177e4 | 1573 | struct sk_buff *skb; |
e27dfcea | 1574 | int sent = 0; |
1da177e4 | 1575 | struct scm_cookie tmp_scm; |
8ba69ba6 | 1576 | bool fds_sent = false; |
25888e30 | 1577 | int max_level; |
1da177e4 LT |
1578 | |
1579 | if (NULL == siocb->scm) | |
1580 | siocb->scm = &tmp_scm; | |
5f23b734 | 1581 | wait_for_unix_gc(); |
1da177e4 LT |
1582 | err = scm_send(sock, msg, siocb->scm); |
1583 | if (err < 0) | |
1584 | return err; | |
1585 | ||
1586 | err = -EOPNOTSUPP; | |
1587 | if (msg->msg_flags&MSG_OOB) | |
1588 | goto out_err; | |
1589 | ||
1590 | if (msg->msg_namelen) { | |
1591 | err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; | |
1592 | goto out_err; | |
1593 | } else { | |
1da177e4 | 1594 | err = -ENOTCONN; |
830a1e5c | 1595 | other = unix_peer(sk); |
1da177e4 LT |
1596 | if (!other) |
1597 | goto out_err; | |
1598 | } | |
1599 | ||
1600 | if (sk->sk_shutdown & SEND_SHUTDOWN) | |
1601 | goto pipe_err; | |
1602 | ||
6eba6a37 | 1603 | while (sent < len) { |
1da177e4 | 1604 | /* |
e9df7d7f BL |
1605 | * Optimisation for the fact that under 0.01% of X |
1606 | * messages typically need breaking up. | |
1da177e4 LT |
1607 | */ |
1608 | ||
e9df7d7f | 1609 | size = len-sent; |
1da177e4 LT |
1610 | |
1611 | /* Keep two messages in the pipe so it schedules better */ | |
e9df7d7f BL |
1612 | if (size > ((sk->sk_sndbuf >> 1) - 64)) |
1613 | size = (sk->sk_sndbuf >> 1) - 64; | |
1da177e4 LT |
1614 | |
1615 | if (size > SKB_MAX_ALLOC) | |
1616 | size = SKB_MAX_ALLOC; | |
ac7bfa62 | 1617 | |
1da177e4 LT |
1618 | /* |
1619 | * Grab a buffer | |
1620 | */ | |
ac7bfa62 | 1621 | |
6eba6a37 ED |
1622 | skb = sock_alloc_send_skb(sk, size, msg->msg_flags&MSG_DONTWAIT, |
1623 | &err); | |
1da177e4 | 1624 | |
e27dfcea | 1625 | if (skb == NULL) |
1da177e4 LT |
1626 | goto out_err; |
1627 | ||
1628 | /* | |
1629 | * If you pass two values to the sock_alloc_send_skb | |
1630 | * it tries to grab the large buffer with GFP_NOFS | |
1631 | * (which can fail easily), and if it fails grab the | |
1632 | * fallback size buffer which is under a page and will | |
1633 | * succeed. [Alan] | |
1634 | */ | |
1635 | size = min_t(int, size, skb_tailroom(skb)); | |
1636 | ||
7361c36c | 1637 | |
8ba69ba6 | 1638 | /* Only send the fds in the first buffer */ |
7361c36c | 1639 | err = unix_scm_to_skb(siocb->scm, skb, !fds_sent); |
25888e30 | 1640 | if (err < 0) { |
7361c36c EB |
1641 | kfree_skb(skb); |
1642 | goto out_err; | |
6209344f | 1643 | } |
25888e30 | 1644 | max_level = err + 1; |
7361c36c | 1645 | fds_sent = true; |
1da177e4 | 1646 | |
6eba6a37 ED |
1647 | err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size); |
1648 | if (err) { | |
1da177e4 LT |
1649 | kfree_skb(skb); |
1650 | goto out_err; | |
1651 | } | |
1652 | ||
1c92b4e5 | 1653 | unix_state_lock(other); |
1da177e4 LT |
1654 | |
1655 | if (sock_flag(other, SOCK_DEAD) || | |
1656 | (other->sk_shutdown & RCV_SHUTDOWN)) | |
1657 | goto pipe_err_free; | |
1658 | ||
1659 | skb_queue_tail(&other->sk_receive_queue, skb); | |
25888e30 ED |
1660 | if (max_level > unix_sk(other)->recursion_level) |
1661 | unix_sk(other)->recursion_level = max_level; | |
1c92b4e5 | 1662 | unix_state_unlock(other); |
1da177e4 | 1663 | other->sk_data_ready(other, size); |
e27dfcea | 1664 | sent += size; |
1da177e4 | 1665 | } |
1da177e4 LT |
1666 | |
1667 | scm_destroy(siocb->scm); | |
1668 | siocb->scm = NULL; | |
1669 | ||
1670 | return sent; | |
1671 | ||
1672 | pipe_err_free: | |
1c92b4e5 | 1673 | unix_state_unlock(other); |
1da177e4 LT |
1674 | kfree_skb(skb); |
1675 | pipe_err: | |
6eba6a37 ED |
1676 | if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL)) |
1677 | send_sig(SIGPIPE, current, 0); | |
1da177e4 LT |
1678 | err = -EPIPE; |
1679 | out_err: | |
1da177e4 LT |
1680 | scm_destroy(siocb->scm); |
1681 | siocb->scm = NULL; | |
1682 | return sent ? : err; | |
1683 | } | |
1684 | ||
1685 | static int unix_seqpacket_sendmsg(struct kiocb *kiocb, struct socket *sock, | |
1686 | struct msghdr *msg, size_t len) | |
1687 | { | |
1688 | int err; | |
1689 | struct sock *sk = sock->sk; | |
ac7bfa62 | 1690 | |
1da177e4 LT |
1691 | err = sock_error(sk); |
1692 | if (err) | |
1693 | return err; | |
1694 | ||
1695 | if (sk->sk_state != TCP_ESTABLISHED) | |
1696 | return -ENOTCONN; | |
1697 | ||
1698 | if (msg->msg_namelen) | |
1699 | msg->msg_namelen = 0; | |
1700 | ||
1701 | return unix_dgram_sendmsg(kiocb, sock, msg, len); | |
1702 | } | |
ac7bfa62 | 1703 | |
a05d2ad1 EB |
1704 | static int unix_seqpacket_recvmsg(struct kiocb *iocb, struct socket *sock, |
1705 | struct msghdr *msg, size_t size, | |
1706 | int flags) | |
1707 | { | |
1708 | struct sock *sk = sock->sk; | |
1709 | ||
1710 | if (sk->sk_state != TCP_ESTABLISHED) | |
1711 | return -ENOTCONN; | |
1712 | ||
1713 | return unix_dgram_recvmsg(iocb, sock, msg, size, flags); | |
1714 | } | |
1715 | ||
1da177e4 LT |
1716 | static void unix_copy_addr(struct msghdr *msg, struct sock *sk) |
1717 | { | |
1718 | struct unix_sock *u = unix_sk(sk); | |
1719 | ||
1720 | msg->msg_namelen = 0; | |
1721 | if (u->addr) { | |
1722 | msg->msg_namelen = u->addr->len; | |
1723 | memcpy(msg->msg_name, u->addr->name, u->addr->len); | |
1724 | } | |
1725 | } | |
1726 | ||
1727 | static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock, | |
1728 | struct msghdr *msg, size_t size, | |
1729 | int flags) | |
1730 | { | |
1731 | struct sock_iocb *siocb = kiocb_to_siocb(iocb); | |
1732 | struct scm_cookie tmp_scm; | |
1733 | struct sock *sk = sock->sk; | |
1734 | struct unix_sock *u = unix_sk(sk); | |
1735 | int noblock = flags & MSG_DONTWAIT; | |
1736 | struct sk_buff *skb; | |
1737 | int err; | |
1738 | ||
1739 | err = -EOPNOTSUPP; | |
1740 | if (flags&MSG_OOB) | |
1741 | goto out; | |
1742 | ||
1743 | msg->msg_namelen = 0; | |
1744 | ||
b3ca9b02 RW |
1745 | err = mutex_lock_interruptible(&u->readlock); |
1746 | if (err) { | |
1747 | err = sock_intr_errno(sock_rcvtimeo(sk, noblock)); | |
1748 | goto out; | |
1749 | } | |
1da177e4 LT |
1750 | |
1751 | skb = skb_recv_datagram(sk, flags, noblock, &err); | |
0a112258 FZ |
1752 | if (!skb) { |
1753 | unix_state_lock(sk); | |
1754 | /* Signal EOF on disconnected non-blocking SEQPACKET socket. */ | |
1755 | if (sk->sk_type == SOCK_SEQPACKET && err == -EAGAIN && | |
1756 | (sk->sk_shutdown & RCV_SHUTDOWN)) | |
1757 | err = 0; | |
1758 | unix_state_unlock(sk); | |
1da177e4 | 1759 | goto out_unlock; |
0a112258 | 1760 | } |
1da177e4 | 1761 | |
67426b75 ED |
1762 | wake_up_interruptible_sync_poll(&u->peer_wait, |
1763 | POLLOUT | POLLWRNORM | POLLWRBAND); | |
1da177e4 LT |
1764 | |
1765 | if (msg->msg_name) | |
1766 | unix_copy_addr(msg, skb->sk); | |
1767 | ||
1768 | if (size > skb->len) | |
1769 | size = skb->len; | |
1770 | else if (size < skb->len) | |
1771 | msg->msg_flags |= MSG_TRUNC; | |
1772 | ||
1773 | err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, size); | |
1774 | if (err) | |
1775 | goto out_free; | |
1776 | ||
3f66116e AC |
1777 | if (sock_flag(sk, SOCK_RCVTSTAMP)) |
1778 | __sock_recv_timestamp(msg, sk, skb); | |
1779 | ||
1da177e4 LT |
1780 | if (!siocb->scm) { |
1781 | siocb->scm = &tmp_scm; | |
1782 | memset(&tmp_scm, 0, sizeof(tmp_scm)); | |
1783 | } | |
7361c36c | 1784 | scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); |
877ce7c1 | 1785 | unix_set_secdata(siocb->scm, skb); |
1da177e4 | 1786 | |
6eba6a37 | 1787 | if (!(flags & MSG_PEEK)) { |
1da177e4 LT |
1788 | if (UNIXCB(skb).fp) |
1789 | unix_detach_fds(siocb->scm, skb); | |
6eba6a37 | 1790 | } else { |
1da177e4 LT |
1791 | /* It is questionable: on PEEK we could: |
1792 | - do not return fds - good, but too simple 8) | |
1793 | - return fds, and do not return them on read (old strategy, | |
1794 | apparently wrong) | |
1795 | - clone fds (I chose it for now, it is the most universal | |
1796 | solution) | |
ac7bfa62 YH |
1797 | |
1798 | POSIX 1003.1g does not actually define this clearly | |
1799 | at all. POSIX 1003.1g doesn't define a lot of things | |
1800 | clearly however! | |
1801 | ||
1da177e4 LT |
1802 | */ |
1803 | if (UNIXCB(skb).fp) | |
1804 | siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); | |
1805 | } | |
1806 | err = size; | |
1807 | ||
1808 | scm_recv(sock, msg, siocb->scm, flags); | |
1809 | ||
1810 | out_free: | |
6eba6a37 | 1811 | skb_free_datagram(sk, skb); |
1da177e4 | 1812 | out_unlock: |
57b47a53 | 1813 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1814 | out: |
1815 | return err; | |
1816 | } | |
1817 | ||
1818 | /* | |
1819 | * Sleep until data has arrive. But check for races.. | |
1820 | */ | |
ac7bfa62 | 1821 | |
6eba6a37 | 1822 | static long unix_stream_data_wait(struct sock *sk, long timeo) |
1da177e4 LT |
1823 | { |
1824 | DEFINE_WAIT(wait); | |
1825 | ||
1c92b4e5 | 1826 | unix_state_lock(sk); |
1da177e4 LT |
1827 | |
1828 | for (;;) { | |
aa395145 | 1829 | prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); |
1da177e4 | 1830 | |
b03efcfb | 1831 | if (!skb_queue_empty(&sk->sk_receive_queue) || |
1da177e4 LT |
1832 | sk->sk_err || |
1833 | (sk->sk_shutdown & RCV_SHUTDOWN) || | |
1834 | signal_pending(current) || | |
1835 | !timeo) | |
1836 | break; | |
1837 | ||
1838 | set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); | |
1c92b4e5 | 1839 | unix_state_unlock(sk); |
1da177e4 | 1840 | timeo = schedule_timeout(timeo); |
1c92b4e5 | 1841 | unix_state_lock(sk); |
1da177e4 LT |
1842 | clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); |
1843 | } | |
1844 | ||
aa395145 | 1845 | finish_wait(sk_sleep(sk), &wait); |
1c92b4e5 | 1846 | unix_state_unlock(sk); |
1da177e4 LT |
1847 | return timeo; |
1848 | } | |
1849 | ||
1850 | ||
1851 | ||
1852 | static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock, | |
1853 | struct msghdr *msg, size_t size, | |
1854 | int flags) | |
1855 | { | |
1856 | struct sock_iocb *siocb = kiocb_to_siocb(iocb); | |
1857 | struct scm_cookie tmp_scm; | |
1858 | struct sock *sk = sock->sk; | |
1859 | struct unix_sock *u = unix_sk(sk); | |
e27dfcea | 1860 | struct sockaddr_un *sunaddr = msg->msg_name; |
1da177e4 LT |
1861 | int copied = 0; |
1862 | int check_creds = 0; | |
1863 | int target; | |
1864 | int err = 0; | |
1865 | long timeo; | |
1866 | ||
1867 | err = -EINVAL; | |
1868 | if (sk->sk_state != TCP_ESTABLISHED) | |
1869 | goto out; | |
1870 | ||
1871 | err = -EOPNOTSUPP; | |
1872 | if (flags&MSG_OOB) | |
1873 | goto out; | |
1874 | ||
1875 | target = sock_rcvlowat(sk, flags&MSG_WAITALL, size); | |
1876 | timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT); | |
1877 | ||
1878 | msg->msg_namelen = 0; | |
1879 | ||
1880 | /* Lock the socket to prevent queue disordering | |
1881 | * while sleeps in memcpy_tomsg | |
1882 | */ | |
1883 | ||
1884 | if (!siocb->scm) { | |
1885 | siocb->scm = &tmp_scm; | |
1886 | memset(&tmp_scm, 0, sizeof(tmp_scm)); | |
1887 | } | |
1888 | ||
b3ca9b02 RW |
1889 | err = mutex_lock_interruptible(&u->readlock); |
1890 | if (err) { | |
1891 | err = sock_intr_errno(timeo); | |
1892 | goto out; | |
1893 | } | |
1da177e4 | 1894 | |
6eba6a37 | 1895 | do { |
1da177e4 LT |
1896 | int chunk; |
1897 | struct sk_buff *skb; | |
1898 | ||
3c0d2f37 | 1899 | unix_state_lock(sk); |
1da177e4 | 1900 | skb = skb_dequeue(&sk->sk_receive_queue); |
6eba6a37 | 1901 | if (skb == NULL) { |
25888e30 | 1902 | unix_sk(sk)->recursion_level = 0; |
1da177e4 | 1903 | if (copied >= target) |
3c0d2f37 | 1904 | goto unlock; |
1da177e4 LT |
1905 | |
1906 | /* | |
1907 | * POSIX 1003.1g mandates this order. | |
1908 | */ | |
ac7bfa62 | 1909 | |
6eba6a37 ED |
1910 | err = sock_error(sk); |
1911 | if (err) | |
3c0d2f37 | 1912 | goto unlock; |
1da177e4 | 1913 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
3c0d2f37 MS |
1914 | goto unlock; |
1915 | ||
1916 | unix_state_unlock(sk); | |
1da177e4 LT |
1917 | err = -EAGAIN; |
1918 | if (!timeo) | |
1919 | break; | |
57b47a53 | 1920 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1921 | |
1922 | timeo = unix_stream_data_wait(sk, timeo); | |
1923 | ||
b3ca9b02 RW |
1924 | if (signal_pending(current) |
1925 | || mutex_lock_interruptible(&u->readlock)) { | |
1da177e4 LT |
1926 | err = sock_intr_errno(timeo); |
1927 | goto out; | |
1928 | } | |
b3ca9b02 | 1929 | |
1da177e4 | 1930 | continue; |
3c0d2f37 MS |
1931 | unlock: |
1932 | unix_state_unlock(sk); | |
1933 | break; | |
1da177e4 | 1934 | } |
3c0d2f37 | 1935 | unix_state_unlock(sk); |
1da177e4 LT |
1936 | |
1937 | if (check_creds) { | |
1938 | /* Never glue messages from different writers */ | |
7361c36c EB |
1939 | if ((UNIXCB(skb).pid != siocb->scm->pid) || |
1940 | (UNIXCB(skb).cred != siocb->scm->cred)) { | |
1da177e4 LT |
1941 | skb_queue_head(&sk->sk_receive_queue, skb); |
1942 | break; | |
1943 | } | |
1944 | } else { | |
1945 | /* Copy credentials */ | |
7361c36c | 1946 | scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); |
1da177e4 LT |
1947 | check_creds = 1; |
1948 | } | |
1949 | ||
1950 | /* Copy address just once */ | |
6eba6a37 | 1951 | if (sunaddr) { |
1da177e4 LT |
1952 | unix_copy_addr(msg, skb->sk); |
1953 | sunaddr = NULL; | |
1954 | } | |
1955 | ||
1956 | chunk = min_t(unsigned int, skb->len, size); | |
1957 | if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) { | |
1958 | skb_queue_head(&sk->sk_receive_queue, skb); | |
1959 | if (copied == 0) | |
1960 | copied = -EFAULT; | |
1961 | break; | |
1962 | } | |
1963 | copied += chunk; | |
1964 | size -= chunk; | |
1965 | ||
1966 | /* Mark read part of skb as used */ | |
6eba6a37 | 1967 | if (!(flags & MSG_PEEK)) { |
1da177e4 LT |
1968 | skb_pull(skb, chunk); |
1969 | ||
1970 | if (UNIXCB(skb).fp) | |
1971 | unix_detach_fds(siocb->scm, skb); | |
1972 | ||
1973 | /* put the skb back if we didn't use it up.. */ | |
6eba6a37 | 1974 | if (skb->len) { |
1da177e4 LT |
1975 | skb_queue_head(&sk->sk_receive_queue, skb); |
1976 | break; | |
1977 | } | |
1978 | ||
70d4bf6d | 1979 | consume_skb(skb); |
1da177e4 LT |
1980 | |
1981 | if (siocb->scm->fp) | |
1982 | break; | |
6eba6a37 | 1983 | } else { |
1da177e4 LT |
1984 | /* It is questionable, see note in unix_dgram_recvmsg. |
1985 | */ | |
1986 | if (UNIXCB(skb).fp) | |
1987 | siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); | |
1988 | ||
1989 | /* put message back and return */ | |
1990 | skb_queue_head(&sk->sk_receive_queue, skb); | |
1991 | break; | |
1992 | } | |
1993 | } while (size); | |
1994 | ||
57b47a53 | 1995 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1996 | scm_recv(sock, msg, siocb->scm, flags); |
1997 | out: | |
1998 | return copied ? : err; | |
1999 | } | |
2000 | ||
2001 | static int unix_shutdown(struct socket *sock, int mode) | |
2002 | { | |
2003 | struct sock *sk = sock->sk; | |
2004 | struct sock *other; | |
2005 | ||
2006 | mode = (mode+1)&(RCV_SHUTDOWN|SEND_SHUTDOWN); | |
2007 | ||
7180a031 AC |
2008 | if (!mode) |
2009 | return 0; | |
2010 | ||
2011 | unix_state_lock(sk); | |
2012 | sk->sk_shutdown |= mode; | |
2013 | other = unix_peer(sk); | |
2014 | if (other) | |
2015 | sock_hold(other); | |
2016 | unix_state_unlock(sk); | |
2017 | sk->sk_state_change(sk); | |
2018 | ||
2019 | if (other && | |
2020 | (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET)) { | |
2021 | ||
2022 | int peer_mode = 0; | |
2023 | ||
2024 | if (mode&RCV_SHUTDOWN) | |
2025 | peer_mode |= SEND_SHUTDOWN; | |
2026 | if (mode&SEND_SHUTDOWN) | |
2027 | peer_mode |= RCV_SHUTDOWN; | |
2028 | unix_state_lock(other); | |
2029 | other->sk_shutdown |= peer_mode; | |
2030 | unix_state_unlock(other); | |
2031 | other->sk_state_change(other); | |
2032 | if (peer_mode == SHUTDOWN_MASK) | |
2033 | sk_wake_async(other, SOCK_WAKE_WAITD, POLL_HUP); | |
2034 | else if (peer_mode & RCV_SHUTDOWN) | |
2035 | sk_wake_async(other, SOCK_WAKE_WAITD, POLL_IN); | |
1da177e4 | 2036 | } |
7180a031 AC |
2037 | if (other) |
2038 | sock_put(other); | |
2039 | ||
1da177e4 LT |
2040 | return 0; |
2041 | } | |
2042 | ||
2043 | static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) | |
2044 | { | |
2045 | struct sock *sk = sock->sk; | |
e27dfcea | 2046 | long amount = 0; |
1da177e4 LT |
2047 | int err; |
2048 | ||
6eba6a37 ED |
2049 | switch (cmd) { |
2050 | case SIOCOUTQ: | |
31e6d363 | 2051 | amount = sk_wmem_alloc_get(sk); |
6eba6a37 ED |
2052 | err = put_user(amount, (int __user *)arg); |
2053 | break; | |
2054 | case SIOCINQ: | |
1da177e4 LT |
2055 | { |
2056 | struct sk_buff *skb; | |
2057 | ||
2058 | if (sk->sk_state == TCP_LISTEN) { | |
2059 | err = -EINVAL; | |
2060 | break; | |
2061 | } | |
2062 | ||
2063 | spin_lock(&sk->sk_receive_queue.lock); | |
2064 | if (sk->sk_type == SOCK_STREAM || | |
2065 | sk->sk_type == SOCK_SEQPACKET) { | |
2066 | skb_queue_walk(&sk->sk_receive_queue, skb) | |
2067 | amount += skb->len; | |
2068 | } else { | |
2069 | skb = skb_peek(&sk->sk_receive_queue); | |
2070 | if (skb) | |
e27dfcea | 2071 | amount = skb->len; |
1da177e4 LT |
2072 | } |
2073 | spin_unlock(&sk->sk_receive_queue.lock); | |
2074 | err = put_user(amount, (int __user *)arg); | |
2075 | break; | |
2076 | } | |
2077 | ||
6eba6a37 ED |
2078 | default: |
2079 | err = -ENOIOCTLCMD; | |
2080 | break; | |
1da177e4 LT |
2081 | } |
2082 | return err; | |
2083 | } | |
2084 | ||
6eba6a37 | 2085 | static unsigned int unix_poll(struct file *file, struct socket *sock, poll_table *wait) |
1da177e4 LT |
2086 | { |
2087 | struct sock *sk = sock->sk; | |
2088 | unsigned int mask; | |
2089 | ||
aa395145 | 2090 | sock_poll_wait(file, sk_sleep(sk), wait); |
1da177e4 LT |
2091 | mask = 0; |
2092 | ||
2093 | /* exceptional events? */ | |
2094 | if (sk->sk_err) | |
2095 | mask |= POLLERR; | |
2096 | if (sk->sk_shutdown == SHUTDOWN_MASK) | |
2097 | mask |= POLLHUP; | |
f348d70a | 2098 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
db40980f | 2099 | mask |= POLLRDHUP | POLLIN | POLLRDNORM; |
1da177e4 LT |
2100 | |
2101 | /* readable? */ | |
db40980f | 2102 | if (!skb_queue_empty(&sk->sk_receive_queue)) |
1da177e4 LT |
2103 | mask |= POLLIN | POLLRDNORM; |
2104 | ||
2105 | /* Connection-based need to check for termination and startup */ | |
6eba6a37 ED |
2106 | if ((sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) && |
2107 | sk->sk_state == TCP_CLOSE) | |
1da177e4 LT |
2108 | mask |= POLLHUP; |
2109 | ||
2110 | /* | |
2111 | * we set writable also when the other side has shut down the | |
2112 | * connection. This prevents stuck sockets. | |
2113 | */ | |
2114 | if (unix_writable(sk)) | |
2115 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; | |
2116 | ||
2117 | return mask; | |
2118 | } | |
2119 | ||
ec0d215f RW |
2120 | static unsigned int unix_dgram_poll(struct file *file, struct socket *sock, |
2121 | poll_table *wait) | |
3c73419c | 2122 | { |
ec0d215f RW |
2123 | struct sock *sk = sock->sk, *other; |
2124 | unsigned int mask, writable; | |
3c73419c | 2125 | |
aa395145 | 2126 | sock_poll_wait(file, sk_sleep(sk), wait); |
3c73419c RW |
2127 | mask = 0; |
2128 | ||
2129 | /* exceptional events? */ | |
2130 | if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue)) | |
2131 | mask |= POLLERR; | |
2132 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
5456f09a | 2133 | mask |= POLLRDHUP | POLLIN | POLLRDNORM; |
3c73419c RW |
2134 | if (sk->sk_shutdown == SHUTDOWN_MASK) |
2135 | mask |= POLLHUP; | |
2136 | ||
2137 | /* readable? */ | |
5456f09a | 2138 | if (!skb_queue_empty(&sk->sk_receive_queue)) |
3c73419c RW |
2139 | mask |= POLLIN | POLLRDNORM; |
2140 | ||
2141 | /* Connection-based need to check for termination and startup */ | |
2142 | if (sk->sk_type == SOCK_SEQPACKET) { | |
2143 | if (sk->sk_state == TCP_CLOSE) | |
2144 | mask |= POLLHUP; | |
2145 | /* connection hasn't started yet? */ | |
2146 | if (sk->sk_state == TCP_SYN_SENT) | |
2147 | return mask; | |
2148 | } | |
2149 | ||
973a34aa ED |
2150 | /* No write status requested, avoid expensive OUT tests. */ |
2151 | if (wait && !(wait->key & (POLLWRBAND | POLLWRNORM | POLLOUT))) | |
2152 | return mask; | |
2153 | ||
ec0d215f | 2154 | writable = unix_writable(sk); |
5456f09a ED |
2155 | other = unix_peer_get(sk); |
2156 | if (other) { | |
2157 | if (unix_peer(other) != sk) { | |
2158 | sock_poll_wait(file, &unix_sk(other)->peer_wait, wait); | |
2159 | if (unix_recvq_full(other)) | |
2160 | writable = 0; | |
ec0d215f | 2161 | } |
5456f09a | 2162 | sock_put(other); |
ec0d215f RW |
2163 | } |
2164 | ||
2165 | if (writable) | |
3c73419c RW |
2166 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; |
2167 | else | |
2168 | set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); | |
2169 | ||
3c73419c RW |
2170 | return mask; |
2171 | } | |
1da177e4 LT |
2172 | |
2173 | #ifdef CONFIG_PROC_FS | |
a53eb3fe PE |
2174 | static struct sock *first_unix_socket(int *i) |
2175 | { | |
2176 | for (*i = 0; *i <= UNIX_HASH_SIZE; (*i)++) { | |
2177 | if (!hlist_empty(&unix_socket_table[*i])) | |
2178 | return __sk_head(&unix_socket_table[*i]); | |
2179 | } | |
2180 | return NULL; | |
2181 | } | |
2182 | ||
2183 | static struct sock *next_unix_socket(int *i, struct sock *s) | |
2184 | { | |
2185 | struct sock *next = sk_next(s); | |
2186 | /* More in this chain? */ | |
2187 | if (next) | |
2188 | return next; | |
2189 | /* Look for next non-empty chain. */ | |
2190 | for ((*i)++; *i <= UNIX_HASH_SIZE; (*i)++) { | |
2191 | if (!hlist_empty(&unix_socket_table[*i])) | |
2192 | return __sk_head(&unix_socket_table[*i]); | |
2193 | } | |
2194 | return NULL; | |
2195 | } | |
2196 | ||
097e66c5 | 2197 | struct unix_iter_state { |
e372c414 | 2198 | struct seq_net_private p; |
097e66c5 DL |
2199 | int i; |
2200 | }; | |
e27dfcea | 2201 | |
1218854a | 2202 | static struct sock *unix_seq_idx(struct seq_file *seq, loff_t pos) |
1da177e4 | 2203 | { |
1218854a | 2204 | struct unix_iter_state *iter = seq->private; |
1da177e4 LT |
2205 | loff_t off = 0; |
2206 | struct sock *s; | |
2207 | ||
097e66c5 | 2208 | for (s = first_unix_socket(&iter->i); s; s = next_unix_socket(&iter->i, s)) { |
1218854a | 2209 | if (sock_net(s) != seq_file_net(seq)) |
097e66c5 | 2210 | continue; |
ac7bfa62 | 2211 | if (off == pos) |
1da177e4 LT |
2212 | return s; |
2213 | ++off; | |
2214 | } | |
2215 | return NULL; | |
2216 | } | |
2217 | ||
1da177e4 | 2218 | static void *unix_seq_start(struct seq_file *seq, loff_t *pos) |
9a429c49 | 2219 | __acquires(unix_table_lock) |
1da177e4 | 2220 | { |
fbe9cc4a | 2221 | spin_lock(&unix_table_lock); |
b9f3124f | 2222 | return *pos ? unix_seq_idx(seq, *pos - 1) : SEQ_START_TOKEN; |
1da177e4 LT |
2223 | } |
2224 | ||
2225 | static void *unix_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2226 | { | |
097e66c5 DL |
2227 | struct unix_iter_state *iter = seq->private; |
2228 | struct sock *sk = v; | |
1da177e4 LT |
2229 | ++*pos; |
2230 | ||
b9f3124f | 2231 | if (v == SEQ_START_TOKEN) |
097e66c5 DL |
2232 | sk = first_unix_socket(&iter->i); |
2233 | else | |
2234 | sk = next_unix_socket(&iter->i, sk); | |
1218854a | 2235 | while (sk && (sock_net(sk) != seq_file_net(seq))) |
097e66c5 DL |
2236 | sk = next_unix_socket(&iter->i, sk); |
2237 | return sk; | |
1da177e4 LT |
2238 | } |
2239 | ||
2240 | static void unix_seq_stop(struct seq_file *seq, void *v) | |
9a429c49 | 2241 | __releases(unix_table_lock) |
1da177e4 | 2242 | { |
fbe9cc4a | 2243 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
2244 | } |
2245 | ||
2246 | static int unix_seq_show(struct seq_file *seq, void *v) | |
2247 | { | |
ac7bfa62 | 2248 | |
b9f3124f | 2249 | if (v == SEQ_START_TOKEN) |
1da177e4 LT |
2250 | seq_puts(seq, "Num RefCount Protocol Flags Type St " |
2251 | "Inode Path\n"); | |
2252 | else { | |
2253 | struct sock *s = v; | |
2254 | struct unix_sock *u = unix_sk(s); | |
1c92b4e5 | 2255 | unix_state_lock(s); |
1da177e4 | 2256 | |
71338aa7 | 2257 | seq_printf(seq, "%pK: %08X %08X %08X %04X %02X %5lu", |
1da177e4 LT |
2258 | s, |
2259 | atomic_read(&s->sk_refcnt), | |
2260 | 0, | |
2261 | s->sk_state == TCP_LISTEN ? __SO_ACCEPTCON : 0, | |
2262 | s->sk_type, | |
2263 | s->sk_socket ? | |
2264 | (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTED : SS_UNCONNECTED) : | |
2265 | (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING), | |
2266 | sock_i_ino(s)); | |
2267 | ||
2268 | if (u->addr) { | |
2269 | int i, len; | |
2270 | seq_putc(seq, ' '); | |
2271 | ||
2272 | i = 0; | |
2273 | len = u->addr->len - sizeof(short); | |
2274 | if (!UNIX_ABSTRACT(s)) | |
2275 | len--; | |
2276 | else { | |
2277 | seq_putc(seq, '@'); | |
2278 | i++; | |
2279 | } | |
2280 | for ( ; i < len; i++) | |
2281 | seq_putc(seq, u->addr->name->sun_path[i]); | |
2282 | } | |
1c92b4e5 | 2283 | unix_state_unlock(s); |
1da177e4 LT |
2284 | seq_putc(seq, '\n'); |
2285 | } | |
2286 | ||
2287 | return 0; | |
2288 | } | |
2289 | ||
56b3d975 | 2290 | static const struct seq_operations unix_seq_ops = { |
1da177e4 LT |
2291 | .start = unix_seq_start, |
2292 | .next = unix_seq_next, | |
2293 | .stop = unix_seq_stop, | |
2294 | .show = unix_seq_show, | |
2295 | }; | |
2296 | ||
1da177e4 LT |
2297 | static int unix_seq_open(struct inode *inode, struct file *file) |
2298 | { | |
e372c414 DL |
2299 | return seq_open_net(inode, file, &unix_seq_ops, |
2300 | sizeof(struct unix_iter_state)); | |
1da177e4 LT |
2301 | } |
2302 | ||
da7071d7 | 2303 | static const struct file_operations unix_seq_fops = { |
1da177e4 LT |
2304 | .owner = THIS_MODULE, |
2305 | .open = unix_seq_open, | |
2306 | .read = seq_read, | |
2307 | .llseek = seq_lseek, | |
e372c414 | 2308 | .release = seq_release_net, |
1da177e4 LT |
2309 | }; |
2310 | ||
2311 | #endif | |
2312 | ||
ec1b4cf7 | 2313 | static const struct net_proto_family unix_family_ops = { |
1da177e4 LT |
2314 | .family = PF_UNIX, |
2315 | .create = unix_create, | |
2316 | .owner = THIS_MODULE, | |
2317 | }; | |
2318 | ||
097e66c5 | 2319 | |
2c8c1e72 | 2320 | static int __net_init unix_net_init(struct net *net) |
097e66c5 DL |
2321 | { |
2322 | int error = -ENOMEM; | |
2323 | ||
a0a53c8b | 2324 | net->unx.sysctl_max_dgram_qlen = 10; |
1597fbc0 PE |
2325 | if (unix_sysctl_register(net)) |
2326 | goto out; | |
d392e497 | 2327 | |
097e66c5 | 2328 | #ifdef CONFIG_PROC_FS |
1597fbc0 PE |
2329 | if (!proc_net_fops_create(net, "unix", 0, &unix_seq_fops)) { |
2330 | unix_sysctl_unregister(net); | |
097e66c5 | 2331 | goto out; |
1597fbc0 | 2332 | } |
097e66c5 DL |
2333 | #endif |
2334 | error = 0; | |
2335 | out: | |
48dcc33e | 2336 | return error; |
097e66c5 DL |
2337 | } |
2338 | ||
2c8c1e72 | 2339 | static void __net_exit unix_net_exit(struct net *net) |
097e66c5 | 2340 | { |
1597fbc0 | 2341 | unix_sysctl_unregister(net); |
097e66c5 DL |
2342 | proc_net_remove(net, "unix"); |
2343 | } | |
2344 | ||
2345 | static struct pernet_operations unix_net_ops = { | |
2346 | .init = unix_net_init, | |
2347 | .exit = unix_net_exit, | |
2348 | }; | |
2349 | ||
1da177e4 LT |
2350 | static int __init af_unix_init(void) |
2351 | { | |
2352 | int rc = -1; | |
2353 | struct sk_buff *dummy_skb; | |
2354 | ||
ef047f5e | 2355 | BUILD_BUG_ON(sizeof(struct unix_skb_parms) > sizeof(dummy_skb->cb)); |
1da177e4 LT |
2356 | |
2357 | rc = proto_register(&unix_proto, 1); | |
ac7bfa62 YH |
2358 | if (rc != 0) { |
2359 | printk(KERN_CRIT "%s: Cannot create unix_sock SLAB cache!\n", | |
0dc47877 | 2360 | __func__); |
1da177e4 LT |
2361 | goto out; |
2362 | } | |
2363 | ||
2364 | sock_register(&unix_family_ops); | |
097e66c5 | 2365 | register_pernet_subsys(&unix_net_ops); |
1da177e4 LT |
2366 | out: |
2367 | return rc; | |
2368 | } | |
2369 | ||
2370 | static void __exit af_unix_exit(void) | |
2371 | { | |
2372 | sock_unregister(PF_UNIX); | |
1da177e4 | 2373 | proto_unregister(&unix_proto); |
097e66c5 | 2374 | unregister_pernet_subsys(&unix_net_ops); |
1da177e4 LT |
2375 | } |
2376 | ||
3d366960 DW |
2377 | /* Earlier than device_initcall() so that other drivers invoking |
2378 | request_module() don't end up in a loop when modprobe tries | |
2379 | to use a UNIX socket. But later than subsys_initcall() because | |
2380 | we depend on stuff initialised there */ | |
2381 | fs_initcall(af_unix_init); | |
1da177e4 LT |
2382 | module_exit(af_unix_exit); |
2383 | ||
2384 | MODULE_LICENSE("GPL"); | |
2385 | MODULE_ALIAS_NETPROTO(PF_UNIX); |