Commit | Line | Data |
---|---|---|
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 | ||
7123aaa3 | 118 | struct hlist_head unix_socket_table[2 * UNIX_HASH_SIZE]; |
fa7ff56f PE |
119 | EXPORT_SYMBOL_GPL(unix_socket_table); |
120 | DEFINE_SPINLOCK(unix_table_lock); | |
121 | EXPORT_SYMBOL_GPL(unix_table_lock); | |
518de9b3 | 122 | static atomic_long_t unix_nr_socks; |
1da177e4 | 123 | |
1da177e4 | 124 | |
7123aaa3 ED |
125 | static struct hlist_head *unix_sockets_unbound(void *addr) |
126 | { | |
127 | unsigned long hash = (unsigned long)addr; | |
128 | ||
129 | hash ^= hash >> 16; | |
130 | hash ^= hash >> 8; | |
131 | hash %= UNIX_HASH_SIZE; | |
132 | return &unix_socket_table[UNIX_HASH_SIZE + hash]; | |
133 | } | |
134 | ||
135 | #define UNIX_ABSTRACT(sk) (unix_sk(sk)->addr->hash < UNIX_HASH_SIZE) | |
1da177e4 | 136 | |
877ce7c1 | 137 | #ifdef CONFIG_SECURITY_NETWORK |
dc49c1f9 | 138 | static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) |
877ce7c1 | 139 | { |
dc49c1f9 | 140 | memcpy(UNIXSID(skb), &scm->secid, sizeof(u32)); |
877ce7c1 CZ |
141 | } |
142 | ||
143 | static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) | |
144 | { | |
dc49c1f9 | 145 | scm->secid = *UNIXSID(skb); |
877ce7c1 CZ |
146 | } |
147 | #else | |
dc49c1f9 | 148 | static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) |
877ce7c1 CZ |
149 | { } |
150 | ||
151 | static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) | |
152 | { } | |
153 | #endif /* CONFIG_SECURITY_NETWORK */ | |
154 | ||
1da177e4 LT |
155 | /* |
156 | * SMP locking strategy: | |
fbe9cc4a | 157 | * hash table is protected with spinlock unix_table_lock |
663717f6 | 158 | * each socket state is protected by separate spin lock. |
1da177e4 LT |
159 | */ |
160 | ||
95c96174 | 161 | static inline unsigned int unix_hash_fold(__wsum n) |
1da177e4 | 162 | { |
95c96174 ED |
163 | unsigned int hash = (__force unsigned int)n; |
164 | ||
1da177e4 LT |
165 | hash ^= hash>>16; |
166 | hash ^= hash>>8; | |
167 | return hash&(UNIX_HASH_SIZE-1); | |
168 | } | |
169 | ||
170 | #define unix_peer(sk) (unix_sk(sk)->peer) | |
171 | ||
172 | static inline int unix_our_peer(struct sock *sk, struct sock *osk) | |
173 | { | |
174 | return unix_peer(osk) == sk; | |
175 | } | |
176 | ||
177 | static inline int unix_may_send(struct sock *sk, struct sock *osk) | |
178 | { | |
6eba6a37 | 179 | return unix_peer(osk) == NULL || unix_our_peer(sk, osk); |
1da177e4 LT |
180 | } |
181 | ||
3c73419c RW |
182 | static inline int unix_recvq_full(struct sock const *sk) |
183 | { | |
184 | return skb_queue_len(&sk->sk_receive_queue) > sk->sk_max_ack_backlog; | |
185 | } | |
186 | ||
fa7ff56f | 187 | struct sock *unix_peer_get(struct sock *s) |
1da177e4 LT |
188 | { |
189 | struct sock *peer; | |
190 | ||
1c92b4e5 | 191 | unix_state_lock(s); |
1da177e4 LT |
192 | peer = unix_peer(s); |
193 | if (peer) | |
194 | sock_hold(peer); | |
1c92b4e5 | 195 | unix_state_unlock(s); |
1da177e4 LT |
196 | return peer; |
197 | } | |
fa7ff56f | 198 | EXPORT_SYMBOL_GPL(unix_peer_get); |
1da177e4 LT |
199 | |
200 | static inline void unix_release_addr(struct unix_address *addr) | |
201 | { | |
202 | if (atomic_dec_and_test(&addr->refcnt)) | |
203 | kfree(addr); | |
204 | } | |
205 | ||
206 | /* | |
207 | * Check unix socket name: | |
208 | * - should be not zero length. | |
209 | * - if started by not zero, should be NULL terminated (FS object) | |
210 | * - if started by zero, it is abstract name. | |
211 | */ | |
ac7bfa62 | 212 | |
95c96174 | 213 | static int unix_mkname(struct sockaddr_un *sunaddr, int len, unsigned int *hashp) |
1da177e4 LT |
214 | { |
215 | if (len <= sizeof(short) || len > sizeof(*sunaddr)) | |
216 | return -EINVAL; | |
217 | if (!sunaddr || sunaddr->sun_family != AF_UNIX) | |
218 | return -EINVAL; | |
219 | if (sunaddr->sun_path[0]) { | |
220 | /* | |
221 | * This may look like an off by one error but it is a bit more | |
222 | * subtle. 108 is the longest valid AF_UNIX path for a binding. | |
25985edc | 223 | * sun_path[108] doesn't as such exist. However in kernel space |
1da177e4 LT |
224 | * we are guaranteed that it is a valid memory location in our |
225 | * kernel address buffer. | |
226 | */ | |
e27dfcea | 227 | ((char *)sunaddr)[len] = 0; |
1da177e4 LT |
228 | len = strlen(sunaddr->sun_path)+1+sizeof(short); |
229 | return len; | |
230 | } | |
231 | ||
07f0757a | 232 | *hashp = unix_hash_fold(csum_partial(sunaddr, len, 0)); |
1da177e4 LT |
233 | return len; |
234 | } | |
235 | ||
236 | static void __unix_remove_socket(struct sock *sk) | |
237 | { | |
238 | sk_del_node_init(sk); | |
239 | } | |
240 | ||
241 | static void __unix_insert_socket(struct hlist_head *list, struct sock *sk) | |
242 | { | |
547b792c | 243 | WARN_ON(!sk_unhashed(sk)); |
1da177e4 LT |
244 | sk_add_node(sk, list); |
245 | } | |
246 | ||
247 | static inline void unix_remove_socket(struct sock *sk) | |
248 | { | |
fbe9cc4a | 249 | spin_lock(&unix_table_lock); |
1da177e4 | 250 | __unix_remove_socket(sk); |
fbe9cc4a | 251 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
252 | } |
253 | ||
254 | static inline void unix_insert_socket(struct hlist_head *list, struct sock *sk) | |
255 | { | |
fbe9cc4a | 256 | spin_lock(&unix_table_lock); |
1da177e4 | 257 | __unix_insert_socket(list, sk); |
fbe9cc4a | 258 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
259 | } |
260 | ||
097e66c5 DL |
261 | static struct sock *__unix_find_socket_byname(struct net *net, |
262 | struct sockaddr_un *sunname, | |
95c96174 | 263 | int len, int type, unsigned int hash) |
1da177e4 LT |
264 | { |
265 | struct sock *s; | |
266 | struct hlist_node *node; | |
267 | ||
268 | sk_for_each(s, node, &unix_socket_table[hash ^ type]) { | |
269 | struct unix_sock *u = unix_sk(s); | |
270 | ||
878628fb | 271 | if (!net_eq(sock_net(s), net)) |
097e66c5 DL |
272 | continue; |
273 | ||
1da177e4 LT |
274 | if (u->addr->len == len && |
275 | !memcmp(u->addr->name, sunname, len)) | |
276 | goto found; | |
277 | } | |
278 | s = NULL; | |
279 | found: | |
280 | return s; | |
281 | } | |
282 | ||
097e66c5 DL |
283 | static inline struct sock *unix_find_socket_byname(struct net *net, |
284 | struct sockaddr_un *sunname, | |
1da177e4 | 285 | int len, int type, |
95c96174 | 286 | unsigned int hash) |
1da177e4 LT |
287 | { |
288 | struct sock *s; | |
289 | ||
fbe9cc4a | 290 | spin_lock(&unix_table_lock); |
097e66c5 | 291 | s = __unix_find_socket_byname(net, sunname, len, type, hash); |
1da177e4 LT |
292 | if (s) |
293 | sock_hold(s); | |
fbe9cc4a | 294 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
295 | return s; |
296 | } | |
297 | ||
6616f788 | 298 | static struct sock *unix_find_socket_byinode(struct inode *i) |
1da177e4 LT |
299 | { |
300 | struct sock *s; | |
301 | struct hlist_node *node; | |
302 | ||
fbe9cc4a | 303 | spin_lock(&unix_table_lock); |
1da177e4 LT |
304 | sk_for_each(s, node, |
305 | &unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) { | |
40ffe67d | 306 | struct dentry *dentry = unix_sk(s)->path.dentry; |
1da177e4 | 307 | |
6eba6a37 | 308 | if (dentry && dentry->d_inode == i) { |
1da177e4 LT |
309 | sock_hold(s); |
310 | goto found; | |
311 | } | |
312 | } | |
313 | s = NULL; | |
314 | found: | |
fbe9cc4a | 315 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
316 | return s; |
317 | } | |
318 | ||
319 | static inline int unix_writable(struct sock *sk) | |
320 | { | |
321 | return (atomic_read(&sk->sk_wmem_alloc) << 2) <= sk->sk_sndbuf; | |
322 | } | |
323 | ||
324 | static void unix_write_space(struct sock *sk) | |
325 | { | |
43815482 ED |
326 | struct socket_wq *wq; |
327 | ||
328 | rcu_read_lock(); | |
1da177e4 | 329 | if (unix_writable(sk)) { |
43815482 ED |
330 | wq = rcu_dereference(sk->sk_wq); |
331 | if (wq_has_sleeper(wq)) | |
67426b75 ED |
332 | wake_up_interruptible_sync_poll(&wq->wait, |
333 | POLLOUT | POLLWRNORM | POLLWRBAND); | |
8d8ad9d7 | 334 | sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); |
1da177e4 | 335 | } |
43815482 | 336 | rcu_read_unlock(); |
1da177e4 LT |
337 | } |
338 | ||
339 | /* When dgram socket disconnects (or changes its peer), we clear its receive | |
340 | * queue of packets arrived from previous peer. First, it allows to do | |
341 | * flow control based only on wmem_alloc; second, sk connected to peer | |
342 | * may receive messages only from that peer. */ | |
343 | static void unix_dgram_disconnected(struct sock *sk, struct sock *other) | |
344 | { | |
b03efcfb | 345 | if (!skb_queue_empty(&sk->sk_receive_queue)) { |
1da177e4 LT |
346 | skb_queue_purge(&sk->sk_receive_queue); |
347 | wake_up_interruptible_all(&unix_sk(sk)->peer_wait); | |
348 | ||
349 | /* If one link of bidirectional dgram pipe is disconnected, | |
350 | * we signal error. Messages are lost. Do not make this, | |
351 | * when peer was not connected to us. | |
352 | */ | |
353 | if (!sock_flag(other, SOCK_DEAD) && unix_peer(other) == sk) { | |
354 | other->sk_err = ECONNRESET; | |
355 | other->sk_error_report(other); | |
356 | } | |
357 | } | |
358 | } | |
359 | ||
360 | static void unix_sock_destructor(struct sock *sk) | |
361 | { | |
362 | struct unix_sock *u = unix_sk(sk); | |
363 | ||
364 | skb_queue_purge(&sk->sk_receive_queue); | |
365 | ||
547b792c IJ |
366 | WARN_ON(atomic_read(&sk->sk_wmem_alloc)); |
367 | WARN_ON(!sk_unhashed(sk)); | |
368 | WARN_ON(sk->sk_socket); | |
1da177e4 | 369 | if (!sock_flag(sk, SOCK_DEAD)) { |
6b41e7dd | 370 | printk(KERN_INFO "Attempt to release alive unix socket: %p\n", sk); |
1da177e4 LT |
371 | return; |
372 | } | |
373 | ||
374 | if (u->addr) | |
375 | unix_release_addr(u->addr); | |
376 | ||
518de9b3 | 377 | atomic_long_dec(&unix_nr_socks); |
6f756a8c | 378 | local_bh_disable(); |
a8076d8d | 379 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); |
6f756a8c | 380 | local_bh_enable(); |
1da177e4 | 381 | #ifdef UNIX_REFCNT_DEBUG |
518de9b3 ED |
382 | printk(KERN_DEBUG "UNIX %p is destroyed, %ld are still alive.\n", sk, |
383 | atomic_long_read(&unix_nr_socks)); | |
1da177e4 LT |
384 | #endif |
385 | } | |
386 | ||
6eba6a37 | 387 | static int unix_release_sock(struct sock *sk, int embrion) |
1da177e4 LT |
388 | { |
389 | struct unix_sock *u = unix_sk(sk); | |
40ffe67d | 390 | struct path path; |
1da177e4 LT |
391 | struct sock *skpair; |
392 | struct sk_buff *skb; | |
393 | int state; | |
394 | ||
395 | unix_remove_socket(sk); | |
396 | ||
397 | /* Clear state */ | |
1c92b4e5 | 398 | unix_state_lock(sk); |
1da177e4 LT |
399 | sock_orphan(sk); |
400 | sk->sk_shutdown = SHUTDOWN_MASK; | |
40ffe67d AV |
401 | path = u->path; |
402 | u->path.dentry = NULL; | |
403 | u->path.mnt = NULL; | |
1da177e4 LT |
404 | state = sk->sk_state; |
405 | sk->sk_state = TCP_CLOSE; | |
1c92b4e5 | 406 | unix_state_unlock(sk); |
1da177e4 LT |
407 | |
408 | wake_up_interruptible_all(&u->peer_wait); | |
409 | ||
e27dfcea | 410 | skpair = unix_peer(sk); |
1da177e4 | 411 | |
e27dfcea | 412 | if (skpair != NULL) { |
1da177e4 | 413 | if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) { |
1c92b4e5 | 414 | unix_state_lock(skpair); |
1da177e4 LT |
415 | /* No more writes */ |
416 | skpair->sk_shutdown = SHUTDOWN_MASK; | |
417 | if (!skb_queue_empty(&sk->sk_receive_queue) || embrion) | |
418 | skpair->sk_err = ECONNRESET; | |
1c92b4e5 | 419 | unix_state_unlock(skpair); |
1da177e4 | 420 | skpair->sk_state_change(skpair); |
8d8ad9d7 | 421 | sk_wake_async(skpair, SOCK_WAKE_WAITD, POLL_HUP); |
1da177e4 LT |
422 | } |
423 | sock_put(skpair); /* It may now die */ | |
424 | unix_peer(sk) = NULL; | |
425 | } | |
426 | ||
427 | /* Try to flush out this socket. Throw out buffers at least */ | |
428 | ||
429 | while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) { | |
e27dfcea | 430 | if (state == TCP_LISTEN) |
1da177e4 LT |
431 | unix_release_sock(skb->sk, 1); |
432 | /* passed fds are erased in the kfree_skb hook */ | |
433 | kfree_skb(skb); | |
434 | } | |
435 | ||
40ffe67d AV |
436 | if (path.dentry) |
437 | path_put(&path); | |
1da177e4 LT |
438 | |
439 | sock_put(sk); | |
440 | ||
441 | /* ---- Socket is dead now and most probably destroyed ---- */ | |
442 | ||
443 | /* | |
444 | * Fixme: BSD difference: In BSD all sockets connected to use get | |
445 | * ECONNRESET and we die on the spot. In Linux we behave | |
446 | * like files and pipes do and wait for the last | |
447 | * dereference. | |
448 | * | |
449 | * Can't we simply set sock->err? | |
450 | * | |
451 | * What the above comment does talk about? --ANK(980817) | |
452 | */ | |
453 | ||
9305cfa4 | 454 | if (unix_tot_inflight) |
ac7bfa62 | 455 | unix_gc(); /* Garbage collect fds */ |
1da177e4 LT |
456 | |
457 | return 0; | |
458 | } | |
459 | ||
109f6e39 EB |
460 | static void init_peercred(struct sock *sk) |
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(task_tgid(current)); | |
466 | sk->sk_peer_cred = get_current_cred(); | |
467 | } | |
468 | ||
469 | static void copy_peercred(struct sock *sk, struct sock *peersk) | |
470 | { | |
471 | put_pid(sk->sk_peer_pid); | |
472 | if (sk->sk_peer_cred) | |
473 | put_cred(sk->sk_peer_cred); | |
474 | sk->sk_peer_pid = get_pid(peersk->sk_peer_pid); | |
475 | sk->sk_peer_cred = get_cred(peersk->sk_peer_cred); | |
476 | } | |
477 | ||
1da177e4 LT |
478 | static int unix_listen(struct socket *sock, int backlog) |
479 | { | |
480 | int err; | |
481 | struct sock *sk = sock->sk; | |
482 | struct unix_sock *u = unix_sk(sk); | |
109f6e39 EB |
483 | struct pid *old_pid = NULL; |
484 | const struct cred *old_cred = NULL; | |
1da177e4 LT |
485 | |
486 | err = -EOPNOTSUPP; | |
6eba6a37 ED |
487 | if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET) |
488 | goto out; /* Only stream/seqpacket sockets accept */ | |
1da177e4 LT |
489 | err = -EINVAL; |
490 | if (!u->addr) | |
6eba6a37 | 491 | goto out; /* No listens on an unbound socket */ |
1c92b4e5 | 492 | unix_state_lock(sk); |
1da177e4 LT |
493 | if (sk->sk_state != TCP_CLOSE && sk->sk_state != TCP_LISTEN) |
494 | goto out_unlock; | |
495 | if (backlog > sk->sk_max_ack_backlog) | |
496 | wake_up_interruptible_all(&u->peer_wait); | |
497 | sk->sk_max_ack_backlog = backlog; | |
498 | sk->sk_state = TCP_LISTEN; | |
499 | /* set credentials so connect can copy them */ | |
109f6e39 | 500 | init_peercred(sk); |
1da177e4 LT |
501 | err = 0; |
502 | ||
503 | out_unlock: | |
1c92b4e5 | 504 | unix_state_unlock(sk); |
109f6e39 EB |
505 | put_pid(old_pid); |
506 | if (old_cred) | |
507 | put_cred(old_cred); | |
1da177e4 LT |
508 | out: |
509 | return err; | |
510 | } | |
511 | ||
512 | static int unix_release(struct socket *); | |
513 | static int unix_bind(struct socket *, struct sockaddr *, int); | |
514 | static int unix_stream_connect(struct socket *, struct sockaddr *, | |
515 | int addr_len, int flags); | |
516 | static int unix_socketpair(struct socket *, struct socket *); | |
517 | static int unix_accept(struct socket *, struct socket *, int); | |
518 | static int unix_getname(struct socket *, struct sockaddr *, int *, int); | |
519 | static unsigned int unix_poll(struct file *, struct socket *, poll_table *); | |
ec0d215f RW |
520 | static unsigned int unix_dgram_poll(struct file *, struct socket *, |
521 | poll_table *); | |
1da177e4 LT |
522 | static int unix_ioctl(struct socket *, unsigned int, unsigned long); |
523 | static int unix_shutdown(struct socket *, int); | |
524 | static int unix_stream_sendmsg(struct kiocb *, struct socket *, | |
525 | struct msghdr *, size_t); | |
526 | static int unix_stream_recvmsg(struct kiocb *, struct socket *, | |
527 | struct msghdr *, size_t, int); | |
528 | static int unix_dgram_sendmsg(struct kiocb *, struct socket *, | |
529 | struct msghdr *, size_t); | |
530 | static int unix_dgram_recvmsg(struct kiocb *, struct socket *, | |
531 | struct msghdr *, size_t, int); | |
532 | static int unix_dgram_connect(struct socket *, struct sockaddr *, | |
533 | int, int); | |
534 | static int unix_seqpacket_sendmsg(struct kiocb *, struct socket *, | |
535 | struct msghdr *, size_t); | |
a05d2ad1 EB |
536 | static int unix_seqpacket_recvmsg(struct kiocb *, struct socket *, |
537 | struct msghdr *, size_t, int); | |
1da177e4 | 538 | |
f55bb7f9 PE |
539 | static void unix_set_peek_off(struct sock *sk, int val) |
540 | { | |
541 | struct unix_sock *u = unix_sk(sk); | |
542 | ||
543 | mutex_lock(&u->readlock); | |
544 | sk->sk_peek_off = val; | |
545 | mutex_unlock(&u->readlock); | |
546 | } | |
547 | ||
548 | ||
90ddc4f0 | 549 | static const struct proto_ops unix_stream_ops = { |
1da177e4 LT |
550 | .family = PF_UNIX, |
551 | .owner = THIS_MODULE, | |
552 | .release = unix_release, | |
553 | .bind = unix_bind, | |
554 | .connect = unix_stream_connect, | |
555 | .socketpair = unix_socketpair, | |
556 | .accept = unix_accept, | |
557 | .getname = unix_getname, | |
558 | .poll = unix_poll, | |
559 | .ioctl = unix_ioctl, | |
560 | .listen = unix_listen, | |
561 | .shutdown = unix_shutdown, | |
562 | .setsockopt = sock_no_setsockopt, | |
563 | .getsockopt = sock_no_getsockopt, | |
564 | .sendmsg = unix_stream_sendmsg, | |
565 | .recvmsg = unix_stream_recvmsg, | |
566 | .mmap = sock_no_mmap, | |
567 | .sendpage = sock_no_sendpage, | |
fc0d7536 | 568 | .set_peek_off = unix_set_peek_off, |
1da177e4 LT |
569 | }; |
570 | ||
90ddc4f0 | 571 | static const struct proto_ops unix_dgram_ops = { |
1da177e4 LT |
572 | .family = PF_UNIX, |
573 | .owner = THIS_MODULE, | |
574 | .release = unix_release, | |
575 | .bind = unix_bind, | |
576 | .connect = unix_dgram_connect, | |
577 | .socketpair = unix_socketpair, | |
578 | .accept = sock_no_accept, | |
579 | .getname = unix_getname, | |
ec0d215f | 580 | .poll = unix_dgram_poll, |
1da177e4 LT |
581 | .ioctl = unix_ioctl, |
582 | .listen = sock_no_listen, | |
583 | .shutdown = unix_shutdown, | |
584 | .setsockopt = sock_no_setsockopt, | |
585 | .getsockopt = sock_no_getsockopt, | |
586 | .sendmsg = unix_dgram_sendmsg, | |
587 | .recvmsg = unix_dgram_recvmsg, | |
588 | .mmap = sock_no_mmap, | |
589 | .sendpage = sock_no_sendpage, | |
f55bb7f9 | 590 | .set_peek_off = unix_set_peek_off, |
1da177e4 LT |
591 | }; |
592 | ||
90ddc4f0 | 593 | static const struct proto_ops unix_seqpacket_ops = { |
1da177e4 LT |
594 | .family = PF_UNIX, |
595 | .owner = THIS_MODULE, | |
596 | .release = unix_release, | |
597 | .bind = unix_bind, | |
598 | .connect = unix_stream_connect, | |
599 | .socketpair = unix_socketpair, | |
600 | .accept = unix_accept, | |
601 | .getname = unix_getname, | |
ec0d215f | 602 | .poll = unix_dgram_poll, |
1da177e4 LT |
603 | .ioctl = unix_ioctl, |
604 | .listen = unix_listen, | |
605 | .shutdown = unix_shutdown, | |
606 | .setsockopt = sock_no_setsockopt, | |
607 | .getsockopt = sock_no_getsockopt, | |
608 | .sendmsg = unix_seqpacket_sendmsg, | |
a05d2ad1 | 609 | .recvmsg = unix_seqpacket_recvmsg, |
1da177e4 LT |
610 | .mmap = sock_no_mmap, |
611 | .sendpage = sock_no_sendpage, | |
f55bb7f9 | 612 | .set_peek_off = unix_set_peek_off, |
1da177e4 LT |
613 | }; |
614 | ||
615 | static struct proto unix_proto = { | |
248969ae ED |
616 | .name = "UNIX", |
617 | .owner = THIS_MODULE, | |
248969ae | 618 | .obj_size = sizeof(struct unix_sock), |
1da177e4 LT |
619 | }; |
620 | ||
a09785a2 IM |
621 | /* |
622 | * AF_UNIX sockets do not interact with hardware, hence they | |
623 | * dont trigger interrupts - so it's safe for them to have | |
624 | * bh-unsafe locking for their sk_receive_queue.lock. Split off | |
625 | * this special lock-class by reinitializing the spinlock key: | |
626 | */ | |
627 | static struct lock_class_key af_unix_sk_receive_queue_lock_key; | |
628 | ||
6eba6a37 | 629 | static struct sock *unix_create1(struct net *net, struct socket *sock) |
1da177e4 LT |
630 | { |
631 | struct sock *sk = NULL; | |
632 | struct unix_sock *u; | |
633 | ||
518de9b3 ED |
634 | atomic_long_inc(&unix_nr_socks); |
635 | if (atomic_long_read(&unix_nr_socks) > 2 * get_max_files()) | |
1da177e4 LT |
636 | goto out; |
637 | ||
6257ff21 | 638 | sk = sk_alloc(net, PF_UNIX, GFP_KERNEL, &unix_proto); |
1da177e4 LT |
639 | if (!sk) |
640 | goto out; | |
641 | ||
6eba6a37 | 642 | sock_init_data(sock, sk); |
a09785a2 IM |
643 | lockdep_set_class(&sk->sk_receive_queue.lock, |
644 | &af_unix_sk_receive_queue_lock_key); | |
1da177e4 LT |
645 | |
646 | sk->sk_write_space = unix_write_space; | |
a0a53c8b | 647 | sk->sk_max_ack_backlog = net->unx.sysctl_max_dgram_qlen; |
1da177e4 LT |
648 | sk->sk_destruct = unix_sock_destructor; |
649 | u = unix_sk(sk); | |
40ffe67d AV |
650 | u->path.dentry = NULL; |
651 | u->path.mnt = NULL; | |
fd19f329 | 652 | spin_lock_init(&u->lock); |
516e0cc5 | 653 | atomic_long_set(&u->inflight, 0); |
1fd05ba5 | 654 | INIT_LIST_HEAD(&u->link); |
57b47a53 | 655 | mutex_init(&u->readlock); /* single task reading lock */ |
1da177e4 | 656 | init_waitqueue_head(&u->peer_wait); |
7123aaa3 | 657 | unix_insert_socket(unix_sockets_unbound(sk), sk); |
1da177e4 | 658 | out: |
284b327b | 659 | if (sk == NULL) |
518de9b3 | 660 | atomic_long_dec(&unix_nr_socks); |
920de804 ED |
661 | else { |
662 | local_bh_disable(); | |
a8076d8d | 663 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); |
920de804 ED |
664 | local_bh_enable(); |
665 | } | |
1da177e4 LT |
666 | return sk; |
667 | } | |
668 | ||
3f378b68 EP |
669 | static int unix_create(struct net *net, struct socket *sock, int protocol, |
670 | int kern) | |
1da177e4 LT |
671 | { |
672 | if (protocol && protocol != PF_UNIX) | |
673 | return -EPROTONOSUPPORT; | |
674 | ||
675 | sock->state = SS_UNCONNECTED; | |
676 | ||
677 | switch (sock->type) { | |
678 | case SOCK_STREAM: | |
679 | sock->ops = &unix_stream_ops; | |
680 | break; | |
681 | /* | |
682 | * Believe it or not BSD has AF_UNIX, SOCK_RAW though | |
683 | * nothing uses it. | |
684 | */ | |
685 | case SOCK_RAW: | |
e27dfcea | 686 | sock->type = SOCK_DGRAM; |
1da177e4 LT |
687 | case SOCK_DGRAM: |
688 | sock->ops = &unix_dgram_ops; | |
689 | break; | |
690 | case SOCK_SEQPACKET: | |
691 | sock->ops = &unix_seqpacket_ops; | |
692 | break; | |
693 | default: | |
694 | return -ESOCKTNOSUPPORT; | |
695 | } | |
696 | ||
1b8d7ae4 | 697 | return unix_create1(net, sock) ? 0 : -ENOMEM; |
1da177e4 LT |
698 | } |
699 | ||
700 | static int unix_release(struct socket *sock) | |
701 | { | |
702 | struct sock *sk = sock->sk; | |
703 | ||
704 | if (!sk) | |
705 | return 0; | |
706 | ||
707 | sock->sk = NULL; | |
708 | ||
6eba6a37 | 709 | return unix_release_sock(sk, 0); |
1da177e4 LT |
710 | } |
711 | ||
712 | static int unix_autobind(struct socket *sock) | |
713 | { | |
714 | struct sock *sk = sock->sk; | |
3b1e0a65 | 715 | struct net *net = sock_net(sk); |
1da177e4 LT |
716 | struct unix_sock *u = unix_sk(sk); |
717 | static u32 ordernum = 1; | |
6eba6a37 | 718 | struct unix_address *addr; |
1da177e4 | 719 | int err; |
8df73ff9 | 720 | unsigned int retries = 0; |
1da177e4 | 721 | |
57b47a53 | 722 | mutex_lock(&u->readlock); |
1da177e4 LT |
723 | |
724 | err = 0; | |
725 | if (u->addr) | |
726 | goto out; | |
727 | ||
728 | err = -ENOMEM; | |
0da974f4 | 729 | addr = kzalloc(sizeof(*addr) + sizeof(short) + 16, GFP_KERNEL); |
1da177e4 LT |
730 | if (!addr) |
731 | goto out; | |
732 | ||
1da177e4 LT |
733 | addr->name->sun_family = AF_UNIX; |
734 | atomic_set(&addr->refcnt, 1); | |
735 | ||
736 | retry: | |
737 | addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + sizeof(short); | |
07f0757a | 738 | addr->hash = unix_hash_fold(csum_partial(addr->name, addr->len, 0)); |
1da177e4 | 739 | |
fbe9cc4a | 740 | spin_lock(&unix_table_lock); |
1da177e4 LT |
741 | ordernum = (ordernum+1)&0xFFFFF; |
742 | ||
097e66c5 | 743 | if (__unix_find_socket_byname(net, addr->name, addr->len, sock->type, |
1da177e4 | 744 | addr->hash)) { |
fbe9cc4a | 745 | spin_unlock(&unix_table_lock); |
8df73ff9 TH |
746 | /* |
747 | * __unix_find_socket_byname() may take long time if many names | |
748 | * are already in use. | |
749 | */ | |
750 | cond_resched(); | |
751 | /* Give up if all names seems to be in use. */ | |
752 | if (retries++ == 0xFFFFF) { | |
753 | err = -ENOSPC; | |
754 | kfree(addr); | |
755 | goto out; | |
756 | } | |
1da177e4 LT |
757 | goto retry; |
758 | } | |
759 | addr->hash ^= sk->sk_type; | |
760 | ||
761 | __unix_remove_socket(sk); | |
762 | u->addr = addr; | |
763 | __unix_insert_socket(&unix_socket_table[addr->hash], sk); | |
fbe9cc4a | 764 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
765 | err = 0; |
766 | ||
57b47a53 | 767 | out: mutex_unlock(&u->readlock); |
1da177e4 LT |
768 | return err; |
769 | } | |
770 | ||
097e66c5 DL |
771 | static struct sock *unix_find_other(struct net *net, |
772 | struct sockaddr_un *sunname, int len, | |
95c96174 | 773 | int type, unsigned int hash, int *error) |
1da177e4 LT |
774 | { |
775 | struct sock *u; | |
421748ec | 776 | struct path path; |
1da177e4 | 777 | int err = 0; |
ac7bfa62 | 778 | |
1da177e4 | 779 | if (sunname->sun_path[0]) { |
421748ec AV |
780 | struct inode *inode; |
781 | err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, &path); | |
1da177e4 LT |
782 | if (err) |
783 | goto fail; | |
421748ec AV |
784 | inode = path.dentry->d_inode; |
785 | err = inode_permission(inode, MAY_WRITE); | |
1da177e4 LT |
786 | if (err) |
787 | goto put_fail; | |
788 | ||
789 | err = -ECONNREFUSED; | |
421748ec | 790 | if (!S_ISSOCK(inode->i_mode)) |
1da177e4 | 791 | goto put_fail; |
6616f788 | 792 | u = unix_find_socket_byinode(inode); |
1da177e4 LT |
793 | if (!u) |
794 | goto put_fail; | |
795 | ||
796 | if (u->sk_type == type) | |
68ac1234 | 797 | touch_atime(&path); |
1da177e4 | 798 | |
421748ec | 799 | path_put(&path); |
1da177e4 | 800 | |
e27dfcea | 801 | err = -EPROTOTYPE; |
1da177e4 LT |
802 | if (u->sk_type != type) { |
803 | sock_put(u); | |
804 | goto fail; | |
805 | } | |
806 | } else { | |
807 | err = -ECONNREFUSED; | |
e27dfcea | 808 | u = unix_find_socket_byname(net, sunname, len, type, hash); |
1da177e4 LT |
809 | if (u) { |
810 | struct dentry *dentry; | |
40ffe67d | 811 | dentry = unix_sk(u)->path.dentry; |
1da177e4 | 812 | if (dentry) |
68ac1234 | 813 | touch_atime(&unix_sk(u)->path); |
1da177e4 LT |
814 | } else |
815 | goto fail; | |
816 | } | |
817 | return u; | |
818 | ||
819 | put_fail: | |
421748ec | 820 | path_put(&path); |
1da177e4 | 821 | fail: |
e27dfcea | 822 | *error = err; |
1da177e4 LT |
823 | return NULL; |
824 | } | |
825 | ||
826 | ||
827 | static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) | |
828 | { | |
829 | struct sock *sk = sock->sk; | |
3b1e0a65 | 830 | struct net *net = sock_net(sk); |
1da177e4 | 831 | struct unix_sock *u = unix_sk(sk); |
e27dfcea | 832 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr; |
dae6ad8f | 833 | char *sun_path = sunaddr->sun_path; |
6eba6a37 | 834 | struct dentry *dentry = NULL; |
dae6ad8f | 835 | struct path path; |
1da177e4 | 836 | int err; |
95c96174 | 837 | unsigned int hash; |
1da177e4 LT |
838 | struct unix_address *addr; |
839 | struct hlist_head *list; | |
840 | ||
841 | err = -EINVAL; | |
842 | if (sunaddr->sun_family != AF_UNIX) | |
843 | goto out; | |
844 | ||
e27dfcea | 845 | if (addr_len == sizeof(short)) { |
1da177e4 LT |
846 | err = unix_autobind(sock); |
847 | goto out; | |
848 | } | |
849 | ||
850 | err = unix_mkname(sunaddr, addr_len, &hash); | |
851 | if (err < 0) | |
852 | goto out; | |
853 | addr_len = err; | |
854 | ||
57b47a53 | 855 | mutex_lock(&u->readlock); |
1da177e4 LT |
856 | |
857 | err = -EINVAL; | |
858 | if (u->addr) | |
859 | goto out_up; | |
860 | ||
861 | err = -ENOMEM; | |
862 | addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL); | |
863 | if (!addr) | |
864 | goto out_up; | |
865 | ||
866 | memcpy(addr->name, sunaddr, addr_len); | |
867 | addr->len = addr_len; | |
868 | addr->hash = hash ^ sk->sk_type; | |
869 | atomic_set(&addr->refcnt, 1); | |
870 | ||
dae6ad8f | 871 | if (sun_path[0]) { |
04fc66e7 | 872 | umode_t mode; |
1da177e4 LT |
873 | err = 0; |
874 | /* | |
875 | * Get the parent directory, calculate the hash for last | |
876 | * component. | |
877 | */ | |
dae6ad8f | 878 | dentry = kern_path_create(AT_FDCWD, sun_path, &path, 0); |
1da177e4 LT |
879 | err = PTR_ERR(dentry); |
880 | if (IS_ERR(dentry)) | |
dae6ad8f | 881 | goto out_mknod_parent; |
f81a0bff | 882 | |
1da177e4 LT |
883 | /* |
884 | * All right, let's create it. | |
885 | */ | |
886 | mode = S_IFSOCK | | |
ce3b0f8d | 887 | (SOCK_INODE(sock)->i_mode & ~current_umask()); |
dae6ad8f | 888 | err = mnt_want_write(path.mnt); |
463c3197 DH |
889 | if (err) |
890 | goto out_mknod_dput; | |
dae6ad8f | 891 | err = security_path_mknod(&path, dentry, mode, 0); |
be6d3e56 KT |
892 | if (err) |
893 | goto out_mknod_drop_write; | |
dae6ad8f | 894 | err = vfs_mknod(path.dentry->d_inode, dentry, mode, 0); |
be6d3e56 | 895 | out_mknod_drop_write: |
dae6ad8f | 896 | mnt_drop_write(path.mnt); |
1da177e4 LT |
897 | if (err) |
898 | goto out_mknod_dput; | |
dae6ad8f AV |
899 | mutex_unlock(&path.dentry->d_inode->i_mutex); |
900 | dput(path.dentry); | |
901 | path.dentry = dentry; | |
1da177e4 LT |
902 | |
903 | addr->hash = UNIX_HASH_SIZE; | |
904 | } | |
905 | ||
fbe9cc4a | 906 | spin_lock(&unix_table_lock); |
1da177e4 | 907 | |
dae6ad8f | 908 | if (!sun_path[0]) { |
1da177e4 | 909 | err = -EADDRINUSE; |
097e66c5 | 910 | if (__unix_find_socket_byname(net, sunaddr, addr_len, |
1da177e4 LT |
911 | sk->sk_type, hash)) { |
912 | unix_release_addr(addr); | |
913 | goto out_unlock; | |
914 | } | |
915 | ||
916 | list = &unix_socket_table[addr->hash]; | |
917 | } else { | |
918 | list = &unix_socket_table[dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1)]; | |
40ffe67d | 919 | u->path = path; |
1da177e4 LT |
920 | } |
921 | ||
922 | err = 0; | |
923 | __unix_remove_socket(sk); | |
924 | u->addr = addr; | |
925 | __unix_insert_socket(list, sk); | |
926 | ||
927 | out_unlock: | |
fbe9cc4a | 928 | spin_unlock(&unix_table_lock); |
1da177e4 | 929 | out_up: |
57b47a53 | 930 | mutex_unlock(&u->readlock); |
1da177e4 LT |
931 | out: |
932 | return err; | |
933 | ||
934 | out_mknod_dput: | |
935 | dput(dentry); | |
dae6ad8f AV |
936 | mutex_unlock(&path.dentry->d_inode->i_mutex); |
937 | path_put(&path); | |
1da177e4 | 938 | out_mknod_parent: |
e27dfcea JK |
939 | if (err == -EEXIST) |
940 | err = -EADDRINUSE; | |
1da177e4 LT |
941 | unix_release_addr(addr); |
942 | goto out_up; | |
943 | } | |
944 | ||
278a3de5 DM |
945 | static void unix_state_double_lock(struct sock *sk1, struct sock *sk2) |
946 | { | |
947 | if (unlikely(sk1 == sk2) || !sk2) { | |
948 | unix_state_lock(sk1); | |
949 | return; | |
950 | } | |
951 | if (sk1 < sk2) { | |
952 | unix_state_lock(sk1); | |
953 | unix_state_lock_nested(sk2); | |
954 | } else { | |
955 | unix_state_lock(sk2); | |
956 | unix_state_lock_nested(sk1); | |
957 | } | |
958 | } | |
959 | ||
960 | static void unix_state_double_unlock(struct sock *sk1, struct sock *sk2) | |
961 | { | |
962 | if (unlikely(sk1 == sk2) || !sk2) { | |
963 | unix_state_unlock(sk1); | |
964 | return; | |
965 | } | |
966 | unix_state_unlock(sk1); | |
967 | unix_state_unlock(sk2); | |
968 | } | |
969 | ||
1da177e4 LT |
970 | static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr, |
971 | int alen, int flags) | |
972 | { | |
973 | struct sock *sk = sock->sk; | |
3b1e0a65 | 974 | struct net *net = sock_net(sk); |
e27dfcea | 975 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)addr; |
1da177e4 | 976 | struct sock *other; |
95c96174 | 977 | unsigned int hash; |
1da177e4 LT |
978 | int err; |
979 | ||
980 | if (addr->sa_family != AF_UNSPEC) { | |
981 | err = unix_mkname(sunaddr, alen, &hash); | |
982 | if (err < 0) | |
983 | goto out; | |
984 | alen = err; | |
985 | ||
986 | if (test_bit(SOCK_PASSCRED, &sock->flags) && | |
987 | !unix_sk(sk)->addr && (err = unix_autobind(sock)) != 0) | |
988 | goto out; | |
989 | ||
278a3de5 | 990 | restart: |
e27dfcea | 991 | other = unix_find_other(net, sunaddr, alen, sock->type, hash, &err); |
1da177e4 LT |
992 | if (!other) |
993 | goto out; | |
994 | ||
278a3de5 DM |
995 | unix_state_double_lock(sk, other); |
996 | ||
997 | /* Apparently VFS overslept socket death. Retry. */ | |
998 | if (sock_flag(other, SOCK_DEAD)) { | |
999 | unix_state_double_unlock(sk, other); | |
1000 | sock_put(other); | |
1001 | goto restart; | |
1002 | } | |
1da177e4 LT |
1003 | |
1004 | err = -EPERM; | |
1005 | if (!unix_may_send(sk, other)) | |
1006 | goto out_unlock; | |
1007 | ||
1008 | err = security_unix_may_send(sk->sk_socket, other->sk_socket); | |
1009 | if (err) | |
1010 | goto out_unlock; | |
1011 | ||
1012 | } else { | |
1013 | /* | |
1014 | * 1003.1g breaking connected state with AF_UNSPEC | |
1015 | */ | |
1016 | other = NULL; | |
278a3de5 | 1017 | unix_state_double_lock(sk, other); |
1da177e4 LT |
1018 | } |
1019 | ||
1020 | /* | |
1021 | * If it was connected, reconnect. | |
1022 | */ | |
1023 | if (unix_peer(sk)) { | |
1024 | struct sock *old_peer = unix_peer(sk); | |
e27dfcea | 1025 | unix_peer(sk) = other; |
278a3de5 | 1026 | unix_state_double_unlock(sk, other); |
1da177e4 LT |
1027 | |
1028 | if (other != old_peer) | |
1029 | unix_dgram_disconnected(sk, old_peer); | |
1030 | sock_put(old_peer); | |
1031 | } else { | |
e27dfcea | 1032 | unix_peer(sk) = other; |
278a3de5 | 1033 | unix_state_double_unlock(sk, other); |
1da177e4 | 1034 | } |
ac7bfa62 | 1035 | return 0; |
1da177e4 LT |
1036 | |
1037 | out_unlock: | |
278a3de5 | 1038 | unix_state_double_unlock(sk, other); |
1da177e4 LT |
1039 | sock_put(other); |
1040 | out: | |
1041 | return err; | |
1042 | } | |
1043 | ||
1044 | static long unix_wait_for_peer(struct sock *other, long timeo) | |
1045 | { | |
1046 | struct unix_sock *u = unix_sk(other); | |
1047 | int sched; | |
1048 | DEFINE_WAIT(wait); | |
1049 | ||
1050 | prepare_to_wait_exclusive(&u->peer_wait, &wait, TASK_INTERRUPTIBLE); | |
1051 | ||
1052 | sched = !sock_flag(other, SOCK_DEAD) && | |
1053 | !(other->sk_shutdown & RCV_SHUTDOWN) && | |
3c73419c | 1054 | unix_recvq_full(other); |
1da177e4 | 1055 | |
1c92b4e5 | 1056 | unix_state_unlock(other); |
1da177e4 LT |
1057 | |
1058 | if (sched) | |
1059 | timeo = schedule_timeout(timeo); | |
1060 | ||
1061 | finish_wait(&u->peer_wait, &wait); | |
1062 | return timeo; | |
1063 | } | |
1064 | ||
1065 | static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr, | |
1066 | int addr_len, int flags) | |
1067 | { | |
e27dfcea | 1068 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr; |
1da177e4 | 1069 | struct sock *sk = sock->sk; |
3b1e0a65 | 1070 | struct net *net = sock_net(sk); |
1da177e4 LT |
1071 | struct unix_sock *u = unix_sk(sk), *newu, *otheru; |
1072 | struct sock *newsk = NULL; | |
1073 | struct sock *other = NULL; | |
1074 | struct sk_buff *skb = NULL; | |
95c96174 | 1075 | unsigned int hash; |
1da177e4 LT |
1076 | int st; |
1077 | int err; | |
1078 | long timeo; | |
1079 | ||
1080 | err = unix_mkname(sunaddr, addr_len, &hash); | |
1081 | if (err < 0) | |
1082 | goto out; | |
1083 | addr_len = err; | |
1084 | ||
f64f9e71 JP |
1085 | if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr && |
1086 | (err = unix_autobind(sock)) != 0) | |
1da177e4 LT |
1087 | goto out; |
1088 | ||
1089 | timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); | |
1090 | ||
1091 | /* First of all allocate resources. | |
1092 | If we will make it after state is locked, | |
1093 | we will have to recheck all again in any case. | |
1094 | */ | |
1095 | ||
1096 | err = -ENOMEM; | |
1097 | ||
1098 | /* create new sock for complete connection */ | |
3b1e0a65 | 1099 | newsk = unix_create1(sock_net(sk), NULL); |
1da177e4 LT |
1100 | if (newsk == NULL) |
1101 | goto out; | |
1102 | ||
1103 | /* Allocate skb for sending to listening sock */ | |
1104 | skb = sock_wmalloc(newsk, 1, 0, GFP_KERNEL); | |
1105 | if (skb == NULL) | |
1106 | goto out; | |
1107 | ||
1108 | restart: | |
1109 | /* Find listening sock. */ | |
097e66c5 | 1110 | other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, hash, &err); |
1da177e4 LT |
1111 | if (!other) |
1112 | goto out; | |
1113 | ||
1114 | /* Latch state of peer */ | |
1c92b4e5 | 1115 | unix_state_lock(other); |
1da177e4 LT |
1116 | |
1117 | /* Apparently VFS overslept socket death. Retry. */ | |
1118 | if (sock_flag(other, SOCK_DEAD)) { | |
1c92b4e5 | 1119 | unix_state_unlock(other); |
1da177e4 LT |
1120 | sock_put(other); |
1121 | goto restart; | |
1122 | } | |
1123 | ||
1124 | err = -ECONNREFUSED; | |
1125 | if (other->sk_state != TCP_LISTEN) | |
1126 | goto out_unlock; | |
77238f2b TS |
1127 | if (other->sk_shutdown & RCV_SHUTDOWN) |
1128 | goto out_unlock; | |
1da177e4 | 1129 | |
3c73419c | 1130 | if (unix_recvq_full(other)) { |
1da177e4 LT |
1131 | err = -EAGAIN; |
1132 | if (!timeo) | |
1133 | goto out_unlock; | |
1134 | ||
1135 | timeo = unix_wait_for_peer(other, timeo); | |
1136 | ||
1137 | err = sock_intr_errno(timeo); | |
1138 | if (signal_pending(current)) | |
1139 | goto out; | |
1140 | sock_put(other); | |
1141 | goto restart; | |
ac7bfa62 | 1142 | } |
1da177e4 LT |
1143 | |
1144 | /* Latch our state. | |
1145 | ||
e5537bfc | 1146 | It is tricky place. We need to grab our state lock and cannot |
1da177e4 LT |
1147 | drop lock on peer. It is dangerous because deadlock is |
1148 | possible. Connect to self case and simultaneous | |
1149 | attempt to connect are eliminated by checking socket | |
1150 | state. other is TCP_LISTEN, if sk is TCP_LISTEN we | |
1151 | check this before attempt to grab lock. | |
1152 | ||
1153 | Well, and we have to recheck the state after socket locked. | |
1154 | */ | |
1155 | st = sk->sk_state; | |
1156 | ||
1157 | switch (st) { | |
1158 | case TCP_CLOSE: | |
1159 | /* This is ok... continue with connect */ | |
1160 | break; | |
1161 | case TCP_ESTABLISHED: | |
1162 | /* Socket is already connected */ | |
1163 | err = -EISCONN; | |
1164 | goto out_unlock; | |
1165 | default: | |
1166 | err = -EINVAL; | |
1167 | goto out_unlock; | |
1168 | } | |
1169 | ||
1c92b4e5 | 1170 | unix_state_lock_nested(sk); |
1da177e4 LT |
1171 | |
1172 | if (sk->sk_state != st) { | |
1c92b4e5 DM |
1173 | unix_state_unlock(sk); |
1174 | unix_state_unlock(other); | |
1da177e4 LT |
1175 | sock_put(other); |
1176 | goto restart; | |
1177 | } | |
1178 | ||
3610cda5 | 1179 | err = security_unix_stream_connect(sk, other, newsk); |
1da177e4 | 1180 | if (err) { |
1c92b4e5 | 1181 | unix_state_unlock(sk); |
1da177e4 LT |
1182 | goto out_unlock; |
1183 | } | |
1184 | ||
1185 | /* The way is open! Fastly set all the necessary fields... */ | |
1186 | ||
1187 | sock_hold(sk); | |
1188 | unix_peer(newsk) = sk; | |
1189 | newsk->sk_state = TCP_ESTABLISHED; | |
1190 | newsk->sk_type = sk->sk_type; | |
109f6e39 | 1191 | init_peercred(newsk); |
1da177e4 | 1192 | newu = unix_sk(newsk); |
eaefd110 | 1193 | RCU_INIT_POINTER(newsk->sk_wq, &newu->peer_wq); |
1da177e4 LT |
1194 | otheru = unix_sk(other); |
1195 | ||
1196 | /* copy address information from listening to new sock*/ | |
1197 | if (otheru->addr) { | |
1198 | atomic_inc(&otheru->addr->refcnt); | |
1199 | newu->addr = otheru->addr; | |
1200 | } | |
40ffe67d AV |
1201 | if (otheru->path.dentry) { |
1202 | path_get(&otheru->path); | |
1203 | newu->path = otheru->path; | |
1da177e4 LT |
1204 | } |
1205 | ||
1206 | /* Set credentials */ | |
109f6e39 | 1207 | copy_peercred(sk, other); |
1da177e4 | 1208 | |
1da177e4 LT |
1209 | sock->state = SS_CONNECTED; |
1210 | sk->sk_state = TCP_ESTABLISHED; | |
830a1e5c BL |
1211 | sock_hold(newsk); |
1212 | ||
1213 | smp_mb__after_atomic_inc(); /* sock_hold() does an atomic_inc() */ | |
1214 | unix_peer(sk) = newsk; | |
1da177e4 | 1215 | |
1c92b4e5 | 1216 | unix_state_unlock(sk); |
1da177e4 LT |
1217 | |
1218 | /* take ten and and send info to listening sock */ | |
1219 | spin_lock(&other->sk_receive_queue.lock); | |
1220 | __skb_queue_tail(&other->sk_receive_queue, skb); | |
1da177e4 | 1221 | spin_unlock(&other->sk_receive_queue.lock); |
1c92b4e5 | 1222 | unix_state_unlock(other); |
1da177e4 LT |
1223 | other->sk_data_ready(other, 0); |
1224 | sock_put(other); | |
1225 | return 0; | |
1226 | ||
1227 | out_unlock: | |
1228 | if (other) | |
1c92b4e5 | 1229 | unix_state_unlock(other); |
1da177e4 LT |
1230 | |
1231 | out: | |
40d44446 | 1232 | kfree_skb(skb); |
1da177e4 LT |
1233 | if (newsk) |
1234 | unix_release_sock(newsk, 0); | |
1235 | if (other) | |
1236 | sock_put(other); | |
1237 | return err; | |
1238 | } | |
1239 | ||
1240 | static int unix_socketpair(struct socket *socka, struct socket *sockb) | |
1241 | { | |
e27dfcea | 1242 | struct sock *ska = socka->sk, *skb = sockb->sk; |
1da177e4 LT |
1243 | |
1244 | /* Join our sockets back to back */ | |
1245 | sock_hold(ska); | |
1246 | sock_hold(skb); | |
e27dfcea JK |
1247 | unix_peer(ska) = skb; |
1248 | unix_peer(skb) = ska; | |
109f6e39 EB |
1249 | init_peercred(ska); |
1250 | init_peercred(skb); | |
1da177e4 LT |
1251 | |
1252 | if (ska->sk_type != SOCK_DGRAM) { | |
1253 | ska->sk_state = TCP_ESTABLISHED; | |
1254 | skb->sk_state = TCP_ESTABLISHED; | |
1255 | socka->state = SS_CONNECTED; | |
1256 | sockb->state = SS_CONNECTED; | |
1257 | } | |
1258 | return 0; | |
1259 | } | |
1260 | ||
1261 | static int unix_accept(struct socket *sock, struct socket *newsock, int flags) | |
1262 | { | |
1263 | struct sock *sk = sock->sk; | |
1264 | struct sock *tsk; | |
1265 | struct sk_buff *skb; | |
1266 | int err; | |
1267 | ||
1268 | err = -EOPNOTSUPP; | |
6eba6a37 | 1269 | if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET) |
1da177e4 LT |
1270 | goto out; |
1271 | ||
1272 | err = -EINVAL; | |
1273 | if (sk->sk_state != TCP_LISTEN) | |
1274 | goto out; | |
1275 | ||
1276 | /* If socket state is TCP_LISTEN it cannot change (for now...), | |
1277 | * so that no locks are necessary. | |
1278 | */ | |
1279 | ||
1280 | skb = skb_recv_datagram(sk, 0, flags&O_NONBLOCK, &err); | |
1281 | if (!skb) { | |
1282 | /* This means receive shutdown. */ | |
1283 | if (err == 0) | |
1284 | err = -EINVAL; | |
1285 | goto out; | |
1286 | } | |
1287 | ||
1288 | tsk = skb->sk; | |
1289 | skb_free_datagram(sk, skb); | |
1290 | wake_up_interruptible(&unix_sk(sk)->peer_wait); | |
1291 | ||
1292 | /* attach accepted sock to socket */ | |
1c92b4e5 | 1293 | unix_state_lock(tsk); |
1da177e4 LT |
1294 | newsock->state = SS_CONNECTED; |
1295 | sock_graft(tsk, newsock); | |
1c92b4e5 | 1296 | unix_state_unlock(tsk); |
1da177e4 LT |
1297 | return 0; |
1298 | ||
1299 | out: | |
1300 | return err; | |
1301 | } | |
1302 | ||
1303 | ||
1304 | static int unix_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len, int peer) | |
1305 | { | |
1306 | struct sock *sk = sock->sk; | |
1307 | struct unix_sock *u; | |
13cfa97b | 1308 | DECLARE_SOCKADDR(struct sockaddr_un *, sunaddr, uaddr); |
1da177e4 LT |
1309 | int err = 0; |
1310 | ||
1311 | if (peer) { | |
1312 | sk = unix_peer_get(sk); | |
1313 | ||
1314 | err = -ENOTCONN; | |
1315 | if (!sk) | |
1316 | goto out; | |
1317 | err = 0; | |
1318 | } else { | |
1319 | sock_hold(sk); | |
1320 | } | |
1321 | ||
1322 | u = unix_sk(sk); | |
1c92b4e5 | 1323 | unix_state_lock(sk); |
1da177e4 LT |
1324 | if (!u->addr) { |
1325 | sunaddr->sun_family = AF_UNIX; | |
1326 | sunaddr->sun_path[0] = 0; | |
1327 | *uaddr_len = sizeof(short); | |
1328 | } else { | |
1329 | struct unix_address *addr = u->addr; | |
1330 | ||
1331 | *uaddr_len = addr->len; | |
1332 | memcpy(sunaddr, addr->name, *uaddr_len); | |
1333 | } | |
1c92b4e5 | 1334 | unix_state_unlock(sk); |
1da177e4 LT |
1335 | sock_put(sk); |
1336 | out: | |
1337 | return err; | |
1338 | } | |
1339 | ||
1340 | static void unix_detach_fds(struct scm_cookie *scm, struct sk_buff *skb) | |
1341 | { | |
1342 | int i; | |
1343 | ||
1344 | scm->fp = UNIXCB(skb).fp; | |
1da177e4 LT |
1345 | UNIXCB(skb).fp = NULL; |
1346 | ||
6eba6a37 | 1347 | for (i = scm->fp->count-1; i >= 0; i--) |
1da177e4 LT |
1348 | unix_notinflight(scm->fp->fp[i]); |
1349 | } | |
1350 | ||
7361c36c | 1351 | static void unix_destruct_scm(struct sk_buff *skb) |
1da177e4 LT |
1352 | { |
1353 | struct scm_cookie scm; | |
1354 | memset(&scm, 0, sizeof(scm)); | |
7361c36c EB |
1355 | scm.pid = UNIXCB(skb).pid; |
1356 | scm.cred = UNIXCB(skb).cred; | |
1357 | if (UNIXCB(skb).fp) | |
1358 | unix_detach_fds(&scm, skb); | |
1da177e4 LT |
1359 | |
1360 | /* Alas, it calls VFS */ | |
1361 | /* So fscking what? fput() had been SMP-safe since the last Summer */ | |
1362 | scm_destroy(&scm); | |
1363 | sock_wfree(skb); | |
1364 | } | |
1365 | ||
25888e30 ED |
1366 | #define MAX_RECURSION_LEVEL 4 |
1367 | ||
6209344f | 1368 | static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb) |
1da177e4 LT |
1369 | { |
1370 | int i; | |
25888e30 ED |
1371 | unsigned char max_level = 0; |
1372 | int unix_sock_count = 0; | |
1373 | ||
1374 | for (i = scm->fp->count - 1; i >= 0; i--) { | |
1375 | struct sock *sk = unix_get_socket(scm->fp->fp[i]); | |
1376 | ||
1377 | if (sk) { | |
1378 | unix_sock_count++; | |
1379 | max_level = max(max_level, | |
1380 | unix_sk(sk)->recursion_level); | |
1381 | } | |
1382 | } | |
1383 | if (unlikely(max_level > MAX_RECURSION_LEVEL)) | |
1384 | return -ETOOMANYREFS; | |
6209344f MS |
1385 | |
1386 | /* | |
1387 | * Need to duplicate file references for the sake of garbage | |
1388 | * collection. Otherwise a socket in the fps might become a | |
1389 | * candidate for GC while the skb is not yet queued. | |
1390 | */ | |
1391 | UNIXCB(skb).fp = scm_fp_dup(scm->fp); | |
1392 | if (!UNIXCB(skb).fp) | |
1393 | return -ENOMEM; | |
1394 | ||
25888e30 ED |
1395 | if (unix_sock_count) { |
1396 | for (i = scm->fp->count - 1; i >= 0; i--) | |
1397 | unix_inflight(scm->fp->fp[i]); | |
1398 | } | |
1399 | return max_level; | |
1da177e4 LT |
1400 | } |
1401 | ||
f78a5fda | 1402 | static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool send_fds) |
7361c36c EB |
1403 | { |
1404 | int err = 0; | |
16e57262 | 1405 | |
f78a5fda | 1406 | UNIXCB(skb).pid = get_pid(scm->pid); |
16e57262 ED |
1407 | if (scm->cred) |
1408 | UNIXCB(skb).cred = get_cred(scm->cred); | |
7361c36c EB |
1409 | UNIXCB(skb).fp = NULL; |
1410 | if (scm->fp && send_fds) | |
1411 | err = unix_attach_fds(scm, skb); | |
1412 | ||
1413 | skb->destructor = unix_destruct_scm; | |
1414 | return err; | |
1415 | } | |
1416 | ||
16e57262 ED |
1417 | /* |
1418 | * Some apps rely on write() giving SCM_CREDENTIALS | |
1419 | * We include credentials if source or destination socket | |
1420 | * asserted SOCK_PASSCRED. | |
1421 | */ | |
1422 | static void maybe_add_creds(struct sk_buff *skb, const struct socket *sock, | |
1423 | const struct sock *other) | |
1424 | { | |
1425 | if (UNIXCB(skb).cred) | |
1426 | return; | |
1427 | if (test_bit(SOCK_PASSCRED, &sock->flags) || | |
1428 | !other->sk_socket || | |
1429 | test_bit(SOCK_PASSCRED, &other->sk_socket->flags)) { | |
1430 | UNIXCB(skb).pid = get_pid(task_tgid(current)); | |
1431 | UNIXCB(skb).cred = get_current_cred(); | |
1432 | } | |
1433 | } | |
1434 | ||
1da177e4 LT |
1435 | /* |
1436 | * Send AF_UNIX data. | |
1437 | */ | |
1438 | ||
1439 | static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, | |
1440 | struct msghdr *msg, size_t len) | |
1441 | { | |
1442 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1443 | struct sock *sk = sock->sk; | |
3b1e0a65 | 1444 | struct net *net = sock_net(sk); |
1da177e4 | 1445 | struct unix_sock *u = unix_sk(sk); |
e27dfcea | 1446 | struct sockaddr_un *sunaddr = msg->msg_name; |
1da177e4 LT |
1447 | struct sock *other = NULL; |
1448 | int namelen = 0; /* fake GCC */ | |
1449 | int err; | |
95c96174 | 1450 | unsigned int hash; |
f78a5fda | 1451 | struct sk_buff *skb; |
1da177e4 LT |
1452 | long timeo; |
1453 | struct scm_cookie tmp_scm; | |
25888e30 | 1454 | int max_level; |
eb6a2481 | 1455 | int data_len = 0; |
1da177e4 LT |
1456 | |
1457 | if (NULL == siocb->scm) | |
1458 | siocb->scm = &tmp_scm; | |
5f23b734 | 1459 | wait_for_unix_gc(); |
1da177e4 LT |
1460 | err = scm_send(sock, msg, siocb->scm); |
1461 | if (err < 0) | |
1462 | return err; | |
1463 | ||
1464 | err = -EOPNOTSUPP; | |
1465 | if (msg->msg_flags&MSG_OOB) | |
1466 | goto out; | |
1467 | ||
1468 | if (msg->msg_namelen) { | |
1469 | err = unix_mkname(sunaddr, msg->msg_namelen, &hash); | |
1470 | if (err < 0) | |
1471 | goto out; | |
1472 | namelen = err; | |
1473 | } else { | |
1474 | sunaddr = NULL; | |
1475 | err = -ENOTCONN; | |
1476 | other = unix_peer_get(sk); | |
1477 | if (!other) | |
1478 | goto out; | |
1479 | } | |
1480 | ||
f64f9e71 JP |
1481 | if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr |
1482 | && (err = unix_autobind(sock)) != 0) | |
1da177e4 LT |
1483 | goto out; |
1484 | ||
1485 | err = -EMSGSIZE; | |
1486 | if (len > sk->sk_sndbuf - 32) | |
1487 | goto out; | |
1488 | ||
eb6a2481 ED |
1489 | if (len > SKB_MAX_ALLOC) |
1490 | data_len = min_t(size_t, | |
1491 | len - SKB_MAX_ALLOC, | |
1492 | MAX_SKB_FRAGS * PAGE_SIZE); | |
1493 | ||
1494 | skb = sock_alloc_send_pskb(sk, len - data_len, data_len, | |
1495 | msg->msg_flags & MSG_DONTWAIT, &err); | |
e27dfcea | 1496 | if (skb == NULL) |
1da177e4 LT |
1497 | goto out; |
1498 | ||
f78a5fda | 1499 | err = unix_scm_to_skb(siocb->scm, skb, true); |
25888e30 | 1500 | if (err < 0) |
7361c36c | 1501 | goto out_free; |
25888e30 | 1502 | max_level = err + 1; |
dc49c1f9 | 1503 | unix_get_secdata(siocb->scm, skb); |
877ce7c1 | 1504 | |
eb6a2481 ED |
1505 | skb_put(skb, len - data_len); |
1506 | skb->data_len = data_len; | |
1507 | skb->len = len; | |
1508 | err = skb_copy_datagram_from_iovec(skb, 0, msg->msg_iov, 0, len); | |
1da177e4 LT |
1509 | if (err) |
1510 | goto out_free; | |
1511 | ||
1512 | timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); | |
1513 | ||
1514 | restart: | |
1515 | if (!other) { | |
1516 | err = -ECONNRESET; | |
1517 | if (sunaddr == NULL) | |
1518 | goto out_free; | |
1519 | ||
097e66c5 | 1520 | other = unix_find_other(net, sunaddr, namelen, sk->sk_type, |
1da177e4 | 1521 | hash, &err); |
e27dfcea | 1522 | if (other == NULL) |
1da177e4 LT |
1523 | goto out_free; |
1524 | } | |
1525 | ||
d6ae3bae AC |
1526 | if (sk_filter(other, skb) < 0) { |
1527 | /* Toss the packet but do not return any error to the sender */ | |
1528 | err = len; | |
1529 | goto out_free; | |
1530 | } | |
1531 | ||
1c92b4e5 | 1532 | unix_state_lock(other); |
1da177e4 LT |
1533 | err = -EPERM; |
1534 | if (!unix_may_send(sk, other)) | |
1535 | goto out_unlock; | |
1536 | ||
1537 | if (sock_flag(other, SOCK_DEAD)) { | |
1538 | /* | |
1539 | * Check with 1003.1g - what should | |
1540 | * datagram error | |
1541 | */ | |
1c92b4e5 | 1542 | unix_state_unlock(other); |
1da177e4 LT |
1543 | sock_put(other); |
1544 | ||
1545 | err = 0; | |
1c92b4e5 | 1546 | unix_state_lock(sk); |
1da177e4 | 1547 | if (unix_peer(sk) == other) { |
e27dfcea | 1548 | unix_peer(sk) = NULL; |
1c92b4e5 | 1549 | unix_state_unlock(sk); |
1da177e4 LT |
1550 | |
1551 | unix_dgram_disconnected(sk, other); | |
1552 | sock_put(other); | |
1553 | err = -ECONNREFUSED; | |
1554 | } else { | |
1c92b4e5 | 1555 | unix_state_unlock(sk); |
1da177e4 LT |
1556 | } |
1557 | ||
1558 | other = NULL; | |
1559 | if (err) | |
1560 | goto out_free; | |
1561 | goto restart; | |
1562 | } | |
1563 | ||
1564 | err = -EPIPE; | |
1565 | if (other->sk_shutdown & RCV_SHUTDOWN) | |
1566 | goto out_unlock; | |
1567 | ||
1568 | if (sk->sk_type != SOCK_SEQPACKET) { | |
1569 | err = security_unix_may_send(sk->sk_socket, other->sk_socket); | |
1570 | if (err) | |
1571 | goto out_unlock; | |
1572 | } | |
1573 | ||
3c73419c | 1574 | if (unix_peer(other) != sk && unix_recvq_full(other)) { |
1da177e4 LT |
1575 | if (!timeo) { |
1576 | err = -EAGAIN; | |
1577 | goto out_unlock; | |
1578 | } | |
1579 | ||
1580 | timeo = unix_wait_for_peer(other, timeo); | |
1581 | ||
1582 | err = sock_intr_errno(timeo); | |
1583 | if (signal_pending(current)) | |
1584 | goto out_free; | |
1585 | ||
1586 | goto restart; | |
1587 | } | |
1588 | ||
3f66116e AC |
1589 | if (sock_flag(other, SOCK_RCVTSTAMP)) |
1590 | __net_timestamp(skb); | |
16e57262 | 1591 | maybe_add_creds(skb, sock, other); |
1da177e4 | 1592 | skb_queue_tail(&other->sk_receive_queue, skb); |
25888e30 ED |
1593 | if (max_level > unix_sk(other)->recursion_level) |
1594 | unix_sk(other)->recursion_level = max_level; | |
1c92b4e5 | 1595 | unix_state_unlock(other); |
1da177e4 LT |
1596 | other->sk_data_ready(other, len); |
1597 | sock_put(other); | |
f78a5fda | 1598 | scm_destroy(siocb->scm); |
1da177e4 LT |
1599 | return len; |
1600 | ||
1601 | out_unlock: | |
1c92b4e5 | 1602 | unix_state_unlock(other); |
1da177e4 LT |
1603 | out_free: |
1604 | kfree_skb(skb); | |
1605 | out: | |
1606 | if (other) | |
1607 | sock_put(other); | |
f78a5fda | 1608 | scm_destroy(siocb->scm); |
1da177e4 LT |
1609 | return err; |
1610 | } | |
1611 | ||
ac7bfa62 | 1612 | |
1da177e4 LT |
1613 | static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, |
1614 | struct msghdr *msg, size_t len) | |
1615 | { | |
1616 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1617 | struct sock *sk = sock->sk; | |
1618 | struct sock *other = NULL; | |
6eba6a37 | 1619 | int err, size; |
f78a5fda | 1620 | struct sk_buff *skb; |
e27dfcea | 1621 | int sent = 0; |
1da177e4 | 1622 | struct scm_cookie tmp_scm; |
8ba69ba6 | 1623 | bool fds_sent = false; |
25888e30 | 1624 | int max_level; |
1da177e4 LT |
1625 | |
1626 | if (NULL == siocb->scm) | |
1627 | siocb->scm = &tmp_scm; | |
5f23b734 | 1628 | wait_for_unix_gc(); |
1da177e4 LT |
1629 | err = scm_send(sock, msg, siocb->scm); |
1630 | if (err < 0) | |
1631 | return err; | |
1632 | ||
1633 | err = -EOPNOTSUPP; | |
1634 | if (msg->msg_flags&MSG_OOB) | |
1635 | goto out_err; | |
1636 | ||
1637 | if (msg->msg_namelen) { | |
1638 | err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; | |
1639 | goto out_err; | |
1640 | } else { | |
1da177e4 | 1641 | err = -ENOTCONN; |
830a1e5c | 1642 | other = unix_peer(sk); |
1da177e4 LT |
1643 | if (!other) |
1644 | goto out_err; | |
1645 | } | |
1646 | ||
1647 | if (sk->sk_shutdown & SEND_SHUTDOWN) | |
1648 | goto pipe_err; | |
1649 | ||
6eba6a37 | 1650 | while (sent < len) { |
1da177e4 | 1651 | /* |
e9df7d7f BL |
1652 | * Optimisation for the fact that under 0.01% of X |
1653 | * messages typically need breaking up. | |
1da177e4 LT |
1654 | */ |
1655 | ||
e9df7d7f | 1656 | size = len-sent; |
1da177e4 LT |
1657 | |
1658 | /* Keep two messages in the pipe so it schedules better */ | |
e9df7d7f BL |
1659 | if (size > ((sk->sk_sndbuf >> 1) - 64)) |
1660 | size = (sk->sk_sndbuf >> 1) - 64; | |
1da177e4 LT |
1661 | |
1662 | if (size > SKB_MAX_ALLOC) | |
1663 | size = SKB_MAX_ALLOC; | |
ac7bfa62 | 1664 | |
1da177e4 LT |
1665 | /* |
1666 | * Grab a buffer | |
1667 | */ | |
ac7bfa62 | 1668 | |
6eba6a37 ED |
1669 | skb = sock_alloc_send_skb(sk, size, msg->msg_flags&MSG_DONTWAIT, |
1670 | &err); | |
1da177e4 | 1671 | |
e27dfcea | 1672 | if (skb == NULL) |
1da177e4 LT |
1673 | goto out_err; |
1674 | ||
1675 | /* | |
1676 | * If you pass two values to the sock_alloc_send_skb | |
1677 | * it tries to grab the large buffer with GFP_NOFS | |
1678 | * (which can fail easily), and if it fails grab the | |
1679 | * fallback size buffer which is under a page and will | |
1680 | * succeed. [Alan] | |
1681 | */ | |
1682 | size = min_t(int, size, skb_tailroom(skb)); | |
1683 | ||
7361c36c | 1684 | |
f78a5fda DM |
1685 | /* Only send the fds in the first buffer */ |
1686 | err = unix_scm_to_skb(siocb->scm, skb, !fds_sent); | |
25888e30 | 1687 | if (err < 0) { |
7361c36c | 1688 | kfree_skb(skb); |
f78a5fda | 1689 | goto out_err; |
6209344f | 1690 | } |
25888e30 | 1691 | max_level = err + 1; |
7361c36c | 1692 | fds_sent = true; |
1da177e4 | 1693 | |
6eba6a37 ED |
1694 | err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size); |
1695 | if (err) { | |
1da177e4 | 1696 | kfree_skb(skb); |
f78a5fda | 1697 | goto out_err; |
1da177e4 LT |
1698 | } |
1699 | ||
1c92b4e5 | 1700 | unix_state_lock(other); |
1da177e4 LT |
1701 | |
1702 | if (sock_flag(other, SOCK_DEAD) || | |
1703 | (other->sk_shutdown & RCV_SHUTDOWN)) | |
1704 | goto pipe_err_free; | |
1705 | ||
16e57262 | 1706 | maybe_add_creds(skb, sock, other); |
1da177e4 | 1707 | skb_queue_tail(&other->sk_receive_queue, skb); |
25888e30 ED |
1708 | if (max_level > unix_sk(other)->recursion_level) |
1709 | unix_sk(other)->recursion_level = max_level; | |
1c92b4e5 | 1710 | unix_state_unlock(other); |
1da177e4 | 1711 | other->sk_data_ready(other, size); |
e27dfcea | 1712 | sent += size; |
1da177e4 | 1713 | } |
1da177e4 | 1714 | |
f78a5fda | 1715 | scm_destroy(siocb->scm); |
1da177e4 LT |
1716 | siocb->scm = NULL; |
1717 | ||
1718 | return sent; | |
1719 | ||
1720 | pipe_err_free: | |
1c92b4e5 | 1721 | unix_state_unlock(other); |
1da177e4 LT |
1722 | kfree_skb(skb); |
1723 | pipe_err: | |
6eba6a37 ED |
1724 | if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL)) |
1725 | send_sig(SIGPIPE, current, 0); | |
1da177e4 LT |
1726 | err = -EPIPE; |
1727 | out_err: | |
f78a5fda | 1728 | scm_destroy(siocb->scm); |
1da177e4 LT |
1729 | siocb->scm = NULL; |
1730 | return sent ? : err; | |
1731 | } | |
1732 | ||
1733 | static int unix_seqpacket_sendmsg(struct kiocb *kiocb, struct socket *sock, | |
1734 | struct msghdr *msg, size_t len) | |
1735 | { | |
1736 | int err; | |
1737 | struct sock *sk = sock->sk; | |
ac7bfa62 | 1738 | |
1da177e4 LT |
1739 | err = sock_error(sk); |
1740 | if (err) | |
1741 | return err; | |
1742 | ||
1743 | if (sk->sk_state != TCP_ESTABLISHED) | |
1744 | return -ENOTCONN; | |
1745 | ||
1746 | if (msg->msg_namelen) | |
1747 | msg->msg_namelen = 0; | |
1748 | ||
1749 | return unix_dgram_sendmsg(kiocb, sock, msg, len); | |
1750 | } | |
ac7bfa62 | 1751 | |
a05d2ad1 EB |
1752 | static int unix_seqpacket_recvmsg(struct kiocb *iocb, struct socket *sock, |
1753 | struct msghdr *msg, size_t size, | |
1754 | int flags) | |
1755 | { | |
1756 | struct sock *sk = sock->sk; | |
1757 | ||
1758 | if (sk->sk_state != TCP_ESTABLISHED) | |
1759 | return -ENOTCONN; | |
1760 | ||
1761 | return unix_dgram_recvmsg(iocb, sock, msg, size, flags); | |
1762 | } | |
1763 | ||
1da177e4 LT |
1764 | static void unix_copy_addr(struct msghdr *msg, struct sock *sk) |
1765 | { | |
1766 | struct unix_sock *u = unix_sk(sk); | |
1767 | ||
1768 | msg->msg_namelen = 0; | |
1769 | if (u->addr) { | |
1770 | msg->msg_namelen = u->addr->len; | |
1771 | memcpy(msg->msg_name, u->addr->name, u->addr->len); | |
1772 | } | |
1773 | } | |
1774 | ||
1775 | static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock, | |
1776 | struct msghdr *msg, size_t size, | |
1777 | int flags) | |
1778 | { | |
1779 | struct sock_iocb *siocb = kiocb_to_siocb(iocb); | |
1780 | struct scm_cookie tmp_scm; | |
1781 | struct sock *sk = sock->sk; | |
1782 | struct unix_sock *u = unix_sk(sk); | |
1783 | int noblock = flags & MSG_DONTWAIT; | |
1784 | struct sk_buff *skb; | |
1785 | int err; | |
f55bb7f9 | 1786 | int peeked, skip; |
1da177e4 LT |
1787 | |
1788 | err = -EOPNOTSUPP; | |
1789 | if (flags&MSG_OOB) | |
1790 | goto out; | |
1791 | ||
1792 | msg->msg_namelen = 0; | |
1793 | ||
b3ca9b02 RW |
1794 | err = mutex_lock_interruptible(&u->readlock); |
1795 | if (err) { | |
1796 | err = sock_intr_errno(sock_rcvtimeo(sk, noblock)); | |
1797 | goto out; | |
1798 | } | |
1da177e4 | 1799 | |
f55bb7f9 PE |
1800 | skip = sk_peek_offset(sk, flags); |
1801 | ||
1802 | skb = __skb_recv_datagram(sk, flags, &peeked, &skip, &err); | |
0a112258 FZ |
1803 | if (!skb) { |
1804 | unix_state_lock(sk); | |
1805 | /* Signal EOF on disconnected non-blocking SEQPACKET socket. */ | |
1806 | if (sk->sk_type == SOCK_SEQPACKET && err == -EAGAIN && | |
1807 | (sk->sk_shutdown & RCV_SHUTDOWN)) | |
1808 | err = 0; | |
1809 | unix_state_unlock(sk); | |
1da177e4 | 1810 | goto out_unlock; |
0a112258 | 1811 | } |
1da177e4 | 1812 | |
67426b75 ED |
1813 | wake_up_interruptible_sync_poll(&u->peer_wait, |
1814 | POLLOUT | POLLWRNORM | POLLWRBAND); | |
1da177e4 LT |
1815 | |
1816 | if (msg->msg_name) | |
1817 | unix_copy_addr(msg, skb->sk); | |
1818 | ||
f55bb7f9 PE |
1819 | if (size > skb->len - skip) |
1820 | size = skb->len - skip; | |
1821 | else if (size < skb->len - skip) | |
1da177e4 LT |
1822 | msg->msg_flags |= MSG_TRUNC; |
1823 | ||
f55bb7f9 | 1824 | err = skb_copy_datagram_iovec(skb, skip, msg->msg_iov, size); |
1da177e4 LT |
1825 | if (err) |
1826 | goto out_free; | |
1827 | ||
3f66116e AC |
1828 | if (sock_flag(sk, SOCK_RCVTSTAMP)) |
1829 | __sock_recv_timestamp(msg, sk, skb); | |
1830 | ||
1da177e4 LT |
1831 | if (!siocb->scm) { |
1832 | siocb->scm = &tmp_scm; | |
1833 | memset(&tmp_scm, 0, sizeof(tmp_scm)); | |
1834 | } | |
f78a5fda | 1835 | scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); |
877ce7c1 | 1836 | unix_set_secdata(siocb->scm, skb); |
1da177e4 | 1837 | |
6eba6a37 | 1838 | if (!(flags & MSG_PEEK)) { |
1da177e4 LT |
1839 | if (UNIXCB(skb).fp) |
1840 | unix_detach_fds(siocb->scm, skb); | |
f55bb7f9 PE |
1841 | |
1842 | sk_peek_offset_bwd(sk, skb->len); | |
6eba6a37 | 1843 | } else { |
1da177e4 LT |
1844 | /* It is questionable: on PEEK we could: |
1845 | - do not return fds - good, but too simple 8) | |
1846 | - return fds, and do not return them on read (old strategy, | |
1847 | apparently wrong) | |
1848 | - clone fds (I chose it for now, it is the most universal | |
1849 | solution) | |
ac7bfa62 YH |
1850 | |
1851 | POSIX 1003.1g does not actually define this clearly | |
1852 | at all. POSIX 1003.1g doesn't define a lot of things | |
1853 | clearly however! | |
1854 | ||
1da177e4 | 1855 | */ |
f55bb7f9 PE |
1856 | |
1857 | sk_peek_offset_fwd(sk, size); | |
1858 | ||
1da177e4 LT |
1859 | if (UNIXCB(skb).fp) |
1860 | siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); | |
1861 | } | |
9f6f9af7 | 1862 | err = (flags & MSG_TRUNC) ? skb->len - skip : size; |
1da177e4 LT |
1863 | |
1864 | scm_recv(sock, msg, siocb->scm, flags); | |
1865 | ||
1866 | out_free: | |
6eba6a37 | 1867 | skb_free_datagram(sk, skb); |
1da177e4 | 1868 | out_unlock: |
57b47a53 | 1869 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1870 | out: |
1871 | return err; | |
1872 | } | |
1873 | ||
1874 | /* | |
1875 | * Sleep until data has arrive. But check for races.. | |
1876 | */ | |
ac7bfa62 | 1877 | |
6eba6a37 | 1878 | static long unix_stream_data_wait(struct sock *sk, long timeo) |
1da177e4 LT |
1879 | { |
1880 | DEFINE_WAIT(wait); | |
1881 | ||
1c92b4e5 | 1882 | unix_state_lock(sk); |
1da177e4 LT |
1883 | |
1884 | for (;;) { | |
aa395145 | 1885 | prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); |
1da177e4 | 1886 | |
b03efcfb | 1887 | if (!skb_queue_empty(&sk->sk_receive_queue) || |
1da177e4 LT |
1888 | sk->sk_err || |
1889 | (sk->sk_shutdown & RCV_SHUTDOWN) || | |
1890 | signal_pending(current) || | |
1891 | !timeo) | |
1892 | break; | |
1893 | ||
1894 | set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); | |
1c92b4e5 | 1895 | unix_state_unlock(sk); |
1da177e4 | 1896 | timeo = schedule_timeout(timeo); |
1c92b4e5 | 1897 | unix_state_lock(sk); |
1da177e4 LT |
1898 | clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); |
1899 | } | |
1900 | ||
aa395145 | 1901 | finish_wait(sk_sleep(sk), &wait); |
1c92b4e5 | 1902 | unix_state_unlock(sk); |
1da177e4 LT |
1903 | return timeo; |
1904 | } | |
1905 | ||
1906 | ||
1907 | ||
1908 | static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock, | |
1909 | struct msghdr *msg, size_t size, | |
1910 | int flags) | |
1911 | { | |
1912 | struct sock_iocb *siocb = kiocb_to_siocb(iocb); | |
1913 | struct scm_cookie tmp_scm; | |
1914 | struct sock *sk = sock->sk; | |
1915 | struct unix_sock *u = unix_sk(sk); | |
e27dfcea | 1916 | struct sockaddr_un *sunaddr = msg->msg_name; |
1da177e4 LT |
1917 | int copied = 0; |
1918 | int check_creds = 0; | |
1919 | int target; | |
1920 | int err = 0; | |
1921 | long timeo; | |
fc0d7536 | 1922 | int skip; |
1da177e4 LT |
1923 | |
1924 | err = -EINVAL; | |
1925 | if (sk->sk_state != TCP_ESTABLISHED) | |
1926 | goto out; | |
1927 | ||
1928 | err = -EOPNOTSUPP; | |
1929 | if (flags&MSG_OOB) | |
1930 | goto out; | |
1931 | ||
1932 | target = sock_rcvlowat(sk, flags&MSG_WAITALL, size); | |
1933 | timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT); | |
1934 | ||
1935 | msg->msg_namelen = 0; | |
1936 | ||
1937 | /* Lock the socket to prevent queue disordering | |
1938 | * while sleeps in memcpy_tomsg | |
1939 | */ | |
1940 | ||
1941 | if (!siocb->scm) { | |
1942 | siocb->scm = &tmp_scm; | |
1943 | memset(&tmp_scm, 0, sizeof(tmp_scm)); | |
1944 | } | |
1945 | ||
b3ca9b02 RW |
1946 | err = mutex_lock_interruptible(&u->readlock); |
1947 | if (err) { | |
1948 | err = sock_intr_errno(timeo); | |
1949 | goto out; | |
1950 | } | |
1da177e4 | 1951 | |
fc0d7536 PE |
1952 | skip = sk_peek_offset(sk, flags); |
1953 | ||
6eba6a37 | 1954 | do { |
1da177e4 LT |
1955 | int chunk; |
1956 | struct sk_buff *skb; | |
1957 | ||
3c0d2f37 | 1958 | unix_state_lock(sk); |
6f01fd6e | 1959 | skb = skb_peek(&sk->sk_receive_queue); |
fc0d7536 | 1960 | again: |
6eba6a37 | 1961 | if (skb == NULL) { |
25888e30 | 1962 | unix_sk(sk)->recursion_level = 0; |
1da177e4 | 1963 | if (copied >= target) |
3c0d2f37 | 1964 | goto unlock; |
1da177e4 LT |
1965 | |
1966 | /* | |
1967 | * POSIX 1003.1g mandates this order. | |
1968 | */ | |
ac7bfa62 | 1969 | |
6eba6a37 ED |
1970 | err = sock_error(sk); |
1971 | if (err) | |
3c0d2f37 | 1972 | goto unlock; |
1da177e4 | 1973 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
3c0d2f37 MS |
1974 | goto unlock; |
1975 | ||
1976 | unix_state_unlock(sk); | |
1da177e4 LT |
1977 | err = -EAGAIN; |
1978 | if (!timeo) | |
1979 | break; | |
57b47a53 | 1980 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1981 | |
1982 | timeo = unix_stream_data_wait(sk, timeo); | |
1983 | ||
b3ca9b02 RW |
1984 | if (signal_pending(current) |
1985 | || mutex_lock_interruptible(&u->readlock)) { | |
1da177e4 LT |
1986 | err = sock_intr_errno(timeo); |
1987 | goto out; | |
1988 | } | |
b3ca9b02 | 1989 | |
1da177e4 | 1990 | continue; |
3c0d2f37 MS |
1991 | unlock: |
1992 | unix_state_unlock(sk); | |
1993 | break; | |
1da177e4 | 1994 | } |
fc0d7536 PE |
1995 | |
1996 | if (skip >= skb->len) { | |
1997 | skip -= skb->len; | |
1998 | skb = skb_peek_next(skb, &sk->sk_receive_queue); | |
1999 | goto again; | |
2000 | } | |
2001 | ||
3c0d2f37 | 2002 | unix_state_unlock(sk); |
1da177e4 LT |
2003 | |
2004 | if (check_creds) { | |
2005 | /* Never glue messages from different writers */ | |
7361c36c | 2006 | if ((UNIXCB(skb).pid != siocb->scm->pid) || |
6f01fd6e | 2007 | (UNIXCB(skb).cred != siocb->scm->cred)) |
1da177e4 | 2008 | break; |
1da177e4 LT |
2009 | } else { |
2010 | /* Copy credentials */ | |
f78a5fda | 2011 | scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); |
1da177e4 LT |
2012 | check_creds = 1; |
2013 | } | |
2014 | ||
2015 | /* Copy address just once */ | |
6eba6a37 | 2016 | if (sunaddr) { |
1da177e4 LT |
2017 | unix_copy_addr(msg, skb->sk); |
2018 | sunaddr = NULL; | |
2019 | } | |
2020 | ||
fc0d7536 PE |
2021 | chunk = min_t(unsigned int, skb->len - skip, size); |
2022 | if (memcpy_toiovec(msg->msg_iov, skb->data + skip, chunk)) { | |
1da177e4 LT |
2023 | if (copied == 0) |
2024 | copied = -EFAULT; | |
2025 | break; | |
2026 | } | |
2027 | copied += chunk; | |
2028 | size -= chunk; | |
2029 | ||
2030 | /* Mark read part of skb as used */ | |
6eba6a37 | 2031 | if (!(flags & MSG_PEEK)) { |
1da177e4 LT |
2032 | skb_pull(skb, chunk); |
2033 | ||
fc0d7536 PE |
2034 | sk_peek_offset_bwd(sk, chunk); |
2035 | ||
1da177e4 LT |
2036 | if (UNIXCB(skb).fp) |
2037 | unix_detach_fds(siocb->scm, skb); | |
2038 | ||
6f01fd6e | 2039 | if (skb->len) |
1da177e4 | 2040 | break; |
1da177e4 | 2041 | |
6f01fd6e | 2042 | skb_unlink(skb, &sk->sk_receive_queue); |
70d4bf6d | 2043 | consume_skb(skb); |
1da177e4 LT |
2044 | |
2045 | if (siocb->scm->fp) | |
2046 | break; | |
6eba6a37 | 2047 | } else { |
1da177e4 LT |
2048 | /* It is questionable, see note in unix_dgram_recvmsg. |
2049 | */ | |
2050 | if (UNIXCB(skb).fp) | |
2051 | siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); | |
2052 | ||
fc0d7536 PE |
2053 | sk_peek_offset_fwd(sk, chunk); |
2054 | ||
1da177e4 LT |
2055 | break; |
2056 | } | |
2057 | } while (size); | |
2058 | ||
57b47a53 | 2059 | mutex_unlock(&u->readlock); |
1da177e4 LT |
2060 | scm_recv(sock, msg, siocb->scm, flags); |
2061 | out: | |
2062 | return copied ? : err; | |
2063 | } | |
2064 | ||
2065 | static int unix_shutdown(struct socket *sock, int mode) | |
2066 | { | |
2067 | struct sock *sk = sock->sk; | |
2068 | struct sock *other; | |
2069 | ||
2070 | mode = (mode+1)&(RCV_SHUTDOWN|SEND_SHUTDOWN); | |
2071 | ||
7180a031 AC |
2072 | if (!mode) |
2073 | return 0; | |
2074 | ||
2075 | unix_state_lock(sk); | |
2076 | sk->sk_shutdown |= mode; | |
2077 | other = unix_peer(sk); | |
2078 | if (other) | |
2079 | sock_hold(other); | |
2080 | unix_state_unlock(sk); | |
2081 | sk->sk_state_change(sk); | |
2082 | ||
2083 | if (other && | |
2084 | (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET)) { | |
2085 | ||
2086 | int peer_mode = 0; | |
2087 | ||
2088 | if (mode&RCV_SHUTDOWN) | |
2089 | peer_mode |= SEND_SHUTDOWN; | |
2090 | if (mode&SEND_SHUTDOWN) | |
2091 | peer_mode |= RCV_SHUTDOWN; | |
2092 | unix_state_lock(other); | |
2093 | other->sk_shutdown |= peer_mode; | |
2094 | unix_state_unlock(other); | |
2095 | other->sk_state_change(other); | |
2096 | if (peer_mode == SHUTDOWN_MASK) | |
2097 | sk_wake_async(other, SOCK_WAKE_WAITD, POLL_HUP); | |
2098 | else if (peer_mode & RCV_SHUTDOWN) | |
2099 | sk_wake_async(other, SOCK_WAKE_WAITD, POLL_IN); | |
1da177e4 | 2100 | } |
7180a031 AC |
2101 | if (other) |
2102 | sock_put(other); | |
2103 | ||
1da177e4 LT |
2104 | return 0; |
2105 | } | |
2106 | ||
885ee74d PE |
2107 | long unix_inq_len(struct sock *sk) |
2108 | { | |
2109 | struct sk_buff *skb; | |
2110 | long amount = 0; | |
2111 | ||
2112 | if (sk->sk_state == TCP_LISTEN) | |
2113 | return -EINVAL; | |
2114 | ||
2115 | spin_lock(&sk->sk_receive_queue.lock); | |
2116 | if (sk->sk_type == SOCK_STREAM || | |
2117 | sk->sk_type == SOCK_SEQPACKET) { | |
2118 | skb_queue_walk(&sk->sk_receive_queue, skb) | |
2119 | amount += skb->len; | |
2120 | } else { | |
2121 | skb = skb_peek(&sk->sk_receive_queue); | |
2122 | if (skb) | |
2123 | amount = skb->len; | |
2124 | } | |
2125 | spin_unlock(&sk->sk_receive_queue.lock); | |
2126 | ||
2127 | return amount; | |
2128 | } | |
2129 | EXPORT_SYMBOL_GPL(unix_inq_len); | |
2130 | ||
2131 | long unix_outq_len(struct sock *sk) | |
2132 | { | |
2133 | return sk_wmem_alloc_get(sk); | |
2134 | } | |
2135 | EXPORT_SYMBOL_GPL(unix_outq_len); | |
2136 | ||
1da177e4 LT |
2137 | static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) |
2138 | { | |
2139 | struct sock *sk = sock->sk; | |
e27dfcea | 2140 | long amount = 0; |
1da177e4 LT |
2141 | int err; |
2142 | ||
6eba6a37 ED |
2143 | switch (cmd) { |
2144 | case SIOCOUTQ: | |
885ee74d | 2145 | amount = unix_outq_len(sk); |
6eba6a37 ED |
2146 | err = put_user(amount, (int __user *)arg); |
2147 | break; | |
2148 | case SIOCINQ: | |
885ee74d PE |
2149 | amount = unix_inq_len(sk); |
2150 | if (amount < 0) | |
2151 | err = amount; | |
2152 | else | |
1da177e4 | 2153 | err = put_user(amount, (int __user *)arg); |
885ee74d | 2154 | break; |
6eba6a37 ED |
2155 | default: |
2156 | err = -ENOIOCTLCMD; | |
2157 | break; | |
1da177e4 LT |
2158 | } |
2159 | return err; | |
2160 | } | |
2161 | ||
6eba6a37 | 2162 | static unsigned int unix_poll(struct file *file, struct socket *sock, poll_table *wait) |
1da177e4 LT |
2163 | { |
2164 | struct sock *sk = sock->sk; | |
2165 | unsigned int mask; | |
2166 | ||
aa395145 | 2167 | sock_poll_wait(file, sk_sleep(sk), wait); |
1da177e4 LT |
2168 | mask = 0; |
2169 | ||
2170 | /* exceptional events? */ | |
2171 | if (sk->sk_err) | |
2172 | mask |= POLLERR; | |
2173 | if (sk->sk_shutdown == SHUTDOWN_MASK) | |
2174 | mask |= POLLHUP; | |
f348d70a | 2175 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
db40980f | 2176 | mask |= POLLRDHUP | POLLIN | POLLRDNORM; |
1da177e4 LT |
2177 | |
2178 | /* readable? */ | |
db40980f | 2179 | if (!skb_queue_empty(&sk->sk_receive_queue)) |
1da177e4 LT |
2180 | mask |= POLLIN | POLLRDNORM; |
2181 | ||
2182 | /* Connection-based need to check for termination and startup */ | |
6eba6a37 ED |
2183 | if ((sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) && |
2184 | sk->sk_state == TCP_CLOSE) | |
1da177e4 LT |
2185 | mask |= POLLHUP; |
2186 | ||
2187 | /* | |
2188 | * we set writable also when the other side has shut down the | |
2189 | * connection. This prevents stuck sockets. | |
2190 | */ | |
2191 | if (unix_writable(sk)) | |
2192 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; | |
2193 | ||
2194 | return mask; | |
2195 | } | |
2196 | ||
ec0d215f RW |
2197 | static unsigned int unix_dgram_poll(struct file *file, struct socket *sock, |
2198 | poll_table *wait) | |
3c73419c | 2199 | { |
ec0d215f RW |
2200 | struct sock *sk = sock->sk, *other; |
2201 | unsigned int mask, writable; | |
3c73419c | 2202 | |
aa395145 | 2203 | sock_poll_wait(file, sk_sleep(sk), wait); |
3c73419c RW |
2204 | mask = 0; |
2205 | ||
2206 | /* exceptional events? */ | |
2207 | if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue)) | |
2208 | mask |= POLLERR; | |
2209 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
5456f09a | 2210 | mask |= POLLRDHUP | POLLIN | POLLRDNORM; |
3c73419c RW |
2211 | if (sk->sk_shutdown == SHUTDOWN_MASK) |
2212 | mask |= POLLHUP; | |
2213 | ||
2214 | /* readable? */ | |
5456f09a | 2215 | if (!skb_queue_empty(&sk->sk_receive_queue)) |
3c73419c RW |
2216 | mask |= POLLIN | POLLRDNORM; |
2217 | ||
2218 | /* Connection-based need to check for termination and startup */ | |
2219 | if (sk->sk_type == SOCK_SEQPACKET) { | |
2220 | if (sk->sk_state == TCP_CLOSE) | |
2221 | mask |= POLLHUP; | |
2222 | /* connection hasn't started yet? */ | |
2223 | if (sk->sk_state == TCP_SYN_SENT) | |
2224 | return mask; | |
2225 | } | |
2226 | ||
973a34aa | 2227 | /* No write status requested, avoid expensive OUT tests. */ |
626cf236 | 2228 | if (!(poll_requested_events(wait) & (POLLWRBAND|POLLWRNORM|POLLOUT))) |
973a34aa ED |
2229 | return mask; |
2230 | ||
ec0d215f | 2231 | writable = unix_writable(sk); |
5456f09a ED |
2232 | other = unix_peer_get(sk); |
2233 | if (other) { | |
2234 | if (unix_peer(other) != sk) { | |
2235 | sock_poll_wait(file, &unix_sk(other)->peer_wait, wait); | |
2236 | if (unix_recvq_full(other)) | |
2237 | writable = 0; | |
ec0d215f | 2238 | } |
5456f09a | 2239 | sock_put(other); |
ec0d215f RW |
2240 | } |
2241 | ||
2242 | if (writable) | |
3c73419c RW |
2243 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; |
2244 | else | |
2245 | set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); | |
2246 | ||
3c73419c RW |
2247 | return mask; |
2248 | } | |
1da177e4 LT |
2249 | |
2250 | #ifdef CONFIG_PROC_FS | |
a53eb3fe | 2251 | |
7123aaa3 ED |
2252 | #define BUCKET_SPACE (BITS_PER_LONG - (UNIX_HASH_BITS + 1) - 1) |
2253 | ||
2254 | #define get_bucket(x) ((x) >> BUCKET_SPACE) | |
2255 | #define get_offset(x) ((x) & ((1L << BUCKET_SPACE) - 1)) | |
2256 | #define set_bucket_offset(b, o) ((b) << BUCKET_SPACE | (o)) | |
a53eb3fe | 2257 | |
097e66c5 | 2258 | struct unix_iter_state { |
e372c414 | 2259 | struct seq_net_private p; |
097e66c5 | 2260 | }; |
e27dfcea | 2261 | |
7123aaa3 | 2262 | static struct sock *unix_from_bucket(struct seq_file *seq, loff_t *pos) |
1da177e4 | 2263 | { |
7123aaa3 ED |
2264 | unsigned long offset = get_offset(*pos); |
2265 | unsigned long bucket = get_bucket(*pos); | |
2266 | struct sock *sk; | |
2267 | unsigned long count = 0; | |
1da177e4 | 2268 | |
7123aaa3 ED |
2269 | for (sk = sk_head(&unix_socket_table[bucket]); sk; sk = sk_next(sk)) { |
2270 | if (sock_net(sk) != seq_file_net(seq)) | |
097e66c5 | 2271 | continue; |
7123aaa3 ED |
2272 | if (++count == offset) |
2273 | break; | |
2274 | } | |
2275 | ||
2276 | return sk; | |
2277 | } | |
2278 | ||
2279 | static struct sock *unix_next_socket(struct seq_file *seq, | |
2280 | struct sock *sk, | |
2281 | loff_t *pos) | |
2282 | { | |
2283 | unsigned long bucket; | |
2284 | ||
2285 | while (sk > (struct sock *)SEQ_START_TOKEN) { | |
2286 | sk = sk_next(sk); | |
2287 | if (!sk) | |
2288 | goto next_bucket; | |
2289 | if (sock_net(sk) == seq_file_net(seq)) | |
2290 | return sk; | |
1da177e4 | 2291 | } |
7123aaa3 ED |
2292 | |
2293 | do { | |
2294 | sk = unix_from_bucket(seq, pos); | |
2295 | if (sk) | |
2296 | return sk; | |
2297 | ||
2298 | next_bucket: | |
2299 | bucket = get_bucket(*pos) + 1; | |
2300 | *pos = set_bucket_offset(bucket, 1); | |
2301 | } while (bucket < ARRAY_SIZE(unix_socket_table)); | |
2302 | ||
1da177e4 LT |
2303 | return NULL; |
2304 | } | |
2305 | ||
1da177e4 | 2306 | static void *unix_seq_start(struct seq_file *seq, loff_t *pos) |
9a429c49 | 2307 | __acquires(unix_table_lock) |
1da177e4 | 2308 | { |
fbe9cc4a | 2309 | spin_lock(&unix_table_lock); |
7123aaa3 ED |
2310 | |
2311 | if (!*pos) | |
2312 | return SEQ_START_TOKEN; | |
2313 | ||
2314 | if (get_bucket(*pos) >= ARRAY_SIZE(unix_socket_table)) | |
2315 | return NULL; | |
2316 | ||
2317 | return unix_next_socket(seq, NULL, pos); | |
1da177e4 LT |
2318 | } |
2319 | ||
2320 | static void *unix_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2321 | { | |
2322 | ++*pos; | |
7123aaa3 | 2323 | return unix_next_socket(seq, v, pos); |
1da177e4 LT |
2324 | } |
2325 | ||
2326 | static void unix_seq_stop(struct seq_file *seq, void *v) | |
9a429c49 | 2327 | __releases(unix_table_lock) |
1da177e4 | 2328 | { |
fbe9cc4a | 2329 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
2330 | } |
2331 | ||
2332 | static int unix_seq_show(struct seq_file *seq, void *v) | |
2333 | { | |
ac7bfa62 | 2334 | |
b9f3124f | 2335 | if (v == SEQ_START_TOKEN) |
1da177e4 LT |
2336 | seq_puts(seq, "Num RefCount Protocol Flags Type St " |
2337 | "Inode Path\n"); | |
2338 | else { | |
2339 | struct sock *s = v; | |
2340 | struct unix_sock *u = unix_sk(s); | |
1c92b4e5 | 2341 | unix_state_lock(s); |
1da177e4 | 2342 | |
71338aa7 | 2343 | seq_printf(seq, "%pK: %08X %08X %08X %04X %02X %5lu", |
1da177e4 LT |
2344 | s, |
2345 | atomic_read(&s->sk_refcnt), | |
2346 | 0, | |
2347 | s->sk_state == TCP_LISTEN ? __SO_ACCEPTCON : 0, | |
2348 | s->sk_type, | |
2349 | s->sk_socket ? | |
2350 | (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTED : SS_UNCONNECTED) : | |
2351 | (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING), | |
2352 | sock_i_ino(s)); | |
2353 | ||
2354 | if (u->addr) { | |
2355 | int i, len; | |
2356 | seq_putc(seq, ' '); | |
2357 | ||
2358 | i = 0; | |
2359 | len = u->addr->len - sizeof(short); | |
2360 | if (!UNIX_ABSTRACT(s)) | |
2361 | len--; | |
2362 | else { | |
2363 | seq_putc(seq, '@'); | |
2364 | i++; | |
2365 | } | |
2366 | for ( ; i < len; i++) | |
2367 | seq_putc(seq, u->addr->name->sun_path[i]); | |
2368 | } | |
1c92b4e5 | 2369 | unix_state_unlock(s); |
1da177e4 LT |
2370 | seq_putc(seq, '\n'); |
2371 | } | |
2372 | ||
2373 | return 0; | |
2374 | } | |
2375 | ||
56b3d975 | 2376 | static const struct seq_operations unix_seq_ops = { |
1da177e4 LT |
2377 | .start = unix_seq_start, |
2378 | .next = unix_seq_next, | |
2379 | .stop = unix_seq_stop, | |
2380 | .show = unix_seq_show, | |
2381 | }; | |
2382 | ||
1da177e4 LT |
2383 | static int unix_seq_open(struct inode *inode, struct file *file) |
2384 | { | |
e372c414 DL |
2385 | return seq_open_net(inode, file, &unix_seq_ops, |
2386 | sizeof(struct unix_iter_state)); | |
1da177e4 LT |
2387 | } |
2388 | ||
da7071d7 | 2389 | static const struct file_operations unix_seq_fops = { |
1da177e4 LT |
2390 | .owner = THIS_MODULE, |
2391 | .open = unix_seq_open, | |
2392 | .read = seq_read, | |
2393 | .llseek = seq_lseek, | |
e372c414 | 2394 | .release = seq_release_net, |
1da177e4 LT |
2395 | }; |
2396 | ||
2397 | #endif | |
2398 | ||
ec1b4cf7 | 2399 | static const struct net_proto_family unix_family_ops = { |
1da177e4 LT |
2400 | .family = PF_UNIX, |
2401 | .create = unix_create, | |
2402 | .owner = THIS_MODULE, | |
2403 | }; | |
2404 | ||
097e66c5 | 2405 | |
2c8c1e72 | 2406 | static int __net_init unix_net_init(struct net *net) |
097e66c5 DL |
2407 | { |
2408 | int error = -ENOMEM; | |
2409 | ||
a0a53c8b | 2410 | net->unx.sysctl_max_dgram_qlen = 10; |
1597fbc0 PE |
2411 | if (unix_sysctl_register(net)) |
2412 | goto out; | |
d392e497 | 2413 | |
097e66c5 | 2414 | #ifdef CONFIG_PROC_FS |
1597fbc0 PE |
2415 | if (!proc_net_fops_create(net, "unix", 0, &unix_seq_fops)) { |
2416 | unix_sysctl_unregister(net); | |
097e66c5 | 2417 | goto out; |
1597fbc0 | 2418 | } |
097e66c5 DL |
2419 | #endif |
2420 | error = 0; | |
2421 | out: | |
48dcc33e | 2422 | return error; |
097e66c5 DL |
2423 | } |
2424 | ||
2c8c1e72 | 2425 | static void __net_exit unix_net_exit(struct net *net) |
097e66c5 | 2426 | { |
1597fbc0 | 2427 | unix_sysctl_unregister(net); |
097e66c5 DL |
2428 | proc_net_remove(net, "unix"); |
2429 | } | |
2430 | ||
2431 | static struct pernet_operations unix_net_ops = { | |
2432 | .init = unix_net_init, | |
2433 | .exit = unix_net_exit, | |
2434 | }; | |
2435 | ||
1da177e4 LT |
2436 | static int __init af_unix_init(void) |
2437 | { | |
2438 | int rc = -1; | |
2439 | struct sk_buff *dummy_skb; | |
2440 | ||
ef047f5e | 2441 | BUILD_BUG_ON(sizeof(struct unix_skb_parms) > sizeof(dummy_skb->cb)); |
1da177e4 LT |
2442 | |
2443 | rc = proto_register(&unix_proto, 1); | |
ac7bfa62 YH |
2444 | if (rc != 0) { |
2445 | printk(KERN_CRIT "%s: Cannot create unix_sock SLAB cache!\n", | |
0dc47877 | 2446 | __func__); |
1da177e4 LT |
2447 | goto out; |
2448 | } | |
2449 | ||
2450 | sock_register(&unix_family_ops); | |
097e66c5 | 2451 | register_pernet_subsys(&unix_net_ops); |
1da177e4 LT |
2452 | out: |
2453 | return rc; | |
2454 | } | |
2455 | ||
2456 | static void __exit af_unix_exit(void) | |
2457 | { | |
2458 | sock_unregister(PF_UNIX); | |
1da177e4 | 2459 | proto_unregister(&unix_proto); |
097e66c5 | 2460 | unregister_pernet_subsys(&unix_net_ops); |
1da177e4 LT |
2461 | } |
2462 | ||
3d366960 DW |
2463 | /* Earlier than device_initcall() so that other drivers invoking |
2464 | request_module() don't end up in a loop when modprobe tries | |
2465 | to use a UNIX socket. But later than subsys_initcall() because | |
2466 | we depend on stuff initialised there */ | |
2467 | fs_initcall(af_unix_init); | |
1da177e4 LT |
2468 | module_exit(af_unix_exit); |
2469 | ||
2470 | MODULE_LICENSE("GPL"); | |
2471 | MODULE_ALIAS_NETPROTO(PF_UNIX); |