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 | ||
fa7ff56f PE |
118 | struct hlist_head unix_socket_table[UNIX_HASH_SIZE + 1]; |
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 LT |
123 | |
124 | #define unix_sockets_unbound (&unix_socket_table[UNIX_HASH_SIZE]) | |
125 | ||
126 | #define UNIX_ABSTRACT(sk) (unix_sk(sk)->addr->hash != UNIX_HASH_SIZE) | |
127 | ||
877ce7c1 | 128 | #ifdef CONFIG_SECURITY_NETWORK |
dc49c1f9 | 129 | static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) |
877ce7c1 | 130 | { |
dc49c1f9 | 131 | memcpy(UNIXSID(skb), &scm->secid, sizeof(u32)); |
877ce7c1 CZ |
132 | } |
133 | ||
134 | static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) | |
135 | { | |
dc49c1f9 | 136 | scm->secid = *UNIXSID(skb); |
877ce7c1 CZ |
137 | } |
138 | #else | |
dc49c1f9 | 139 | static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) |
877ce7c1 CZ |
140 | { } |
141 | ||
142 | static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) | |
143 | { } | |
144 | #endif /* CONFIG_SECURITY_NETWORK */ | |
145 | ||
1da177e4 LT |
146 | /* |
147 | * SMP locking strategy: | |
fbe9cc4a | 148 | * hash table is protected with spinlock unix_table_lock |
663717f6 | 149 | * each socket state is protected by separate spin lock. |
1da177e4 LT |
150 | */ |
151 | ||
44bb9363 | 152 | static inline unsigned unix_hash_fold(__wsum n) |
1da177e4 | 153 | { |
44bb9363 | 154 | unsigned hash = (__force unsigned)n; |
1da177e4 LT |
155 | hash ^= hash>>16; |
156 | hash ^= hash>>8; | |
157 | return hash&(UNIX_HASH_SIZE-1); | |
158 | } | |
159 | ||
160 | #define unix_peer(sk) (unix_sk(sk)->peer) | |
161 | ||
162 | static inline int unix_our_peer(struct sock *sk, struct sock *osk) | |
163 | { | |
164 | return unix_peer(osk) == sk; | |
165 | } | |
166 | ||
167 | static inline int unix_may_send(struct sock *sk, struct sock *osk) | |
168 | { | |
6eba6a37 | 169 | return unix_peer(osk) == NULL || unix_our_peer(sk, osk); |
1da177e4 LT |
170 | } |
171 | ||
3c73419c RW |
172 | static inline int unix_recvq_full(struct sock const *sk) |
173 | { | |
174 | return skb_queue_len(&sk->sk_receive_queue) > sk->sk_max_ack_backlog; | |
175 | } | |
176 | ||
fa7ff56f | 177 | struct sock *unix_peer_get(struct sock *s) |
1da177e4 LT |
178 | { |
179 | struct sock *peer; | |
180 | ||
1c92b4e5 | 181 | unix_state_lock(s); |
1da177e4 LT |
182 | peer = unix_peer(s); |
183 | if (peer) | |
184 | sock_hold(peer); | |
1c92b4e5 | 185 | unix_state_unlock(s); |
1da177e4 LT |
186 | return peer; |
187 | } | |
fa7ff56f | 188 | EXPORT_SYMBOL_GPL(unix_peer_get); |
1da177e4 LT |
189 | |
190 | static inline void unix_release_addr(struct unix_address *addr) | |
191 | { | |
192 | if (atomic_dec_and_test(&addr->refcnt)) | |
193 | kfree(addr); | |
194 | } | |
195 | ||
196 | /* | |
197 | * Check unix socket name: | |
198 | * - should be not zero length. | |
199 | * - if started by not zero, should be NULL terminated (FS object) | |
200 | * - if started by zero, it is abstract name. | |
201 | */ | |
ac7bfa62 | 202 | |
6eba6a37 | 203 | static int unix_mkname(struct sockaddr_un *sunaddr, int len, unsigned *hashp) |
1da177e4 LT |
204 | { |
205 | if (len <= sizeof(short) || len > sizeof(*sunaddr)) | |
206 | return -EINVAL; | |
207 | if (!sunaddr || sunaddr->sun_family != AF_UNIX) | |
208 | return -EINVAL; | |
209 | if (sunaddr->sun_path[0]) { | |
210 | /* | |
211 | * This may look like an off by one error but it is a bit more | |
212 | * subtle. 108 is the longest valid AF_UNIX path for a binding. | |
25985edc | 213 | * sun_path[108] doesn't as such exist. However in kernel space |
1da177e4 LT |
214 | * we are guaranteed that it is a valid memory location in our |
215 | * kernel address buffer. | |
216 | */ | |
e27dfcea | 217 | ((char *)sunaddr)[len] = 0; |
1da177e4 LT |
218 | len = strlen(sunaddr->sun_path)+1+sizeof(short); |
219 | return len; | |
220 | } | |
221 | ||
07f0757a | 222 | *hashp = unix_hash_fold(csum_partial(sunaddr, len, 0)); |
1da177e4 LT |
223 | return len; |
224 | } | |
225 | ||
226 | static void __unix_remove_socket(struct sock *sk) | |
227 | { | |
228 | sk_del_node_init(sk); | |
229 | } | |
230 | ||
231 | static void __unix_insert_socket(struct hlist_head *list, struct sock *sk) | |
232 | { | |
547b792c | 233 | WARN_ON(!sk_unhashed(sk)); |
1da177e4 LT |
234 | sk_add_node(sk, list); |
235 | } | |
236 | ||
237 | static inline void unix_remove_socket(struct sock *sk) | |
238 | { | |
fbe9cc4a | 239 | spin_lock(&unix_table_lock); |
1da177e4 | 240 | __unix_remove_socket(sk); |
fbe9cc4a | 241 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
242 | } |
243 | ||
244 | static inline void unix_insert_socket(struct hlist_head *list, struct sock *sk) | |
245 | { | |
fbe9cc4a | 246 | spin_lock(&unix_table_lock); |
1da177e4 | 247 | __unix_insert_socket(list, sk); |
fbe9cc4a | 248 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
249 | } |
250 | ||
097e66c5 DL |
251 | static struct sock *__unix_find_socket_byname(struct net *net, |
252 | struct sockaddr_un *sunname, | |
1da177e4 LT |
253 | int len, int type, unsigned hash) |
254 | { | |
255 | struct sock *s; | |
256 | struct hlist_node *node; | |
257 | ||
258 | sk_for_each(s, node, &unix_socket_table[hash ^ type]) { | |
259 | struct unix_sock *u = unix_sk(s); | |
260 | ||
878628fb | 261 | if (!net_eq(sock_net(s), net)) |
097e66c5 DL |
262 | continue; |
263 | ||
1da177e4 LT |
264 | if (u->addr->len == len && |
265 | !memcmp(u->addr->name, sunname, len)) | |
266 | goto found; | |
267 | } | |
268 | s = NULL; | |
269 | found: | |
270 | return s; | |
271 | } | |
272 | ||
097e66c5 DL |
273 | static inline struct sock *unix_find_socket_byname(struct net *net, |
274 | struct sockaddr_un *sunname, | |
1da177e4 LT |
275 | int len, int type, |
276 | unsigned hash) | |
277 | { | |
278 | struct sock *s; | |
279 | ||
fbe9cc4a | 280 | spin_lock(&unix_table_lock); |
097e66c5 | 281 | s = __unix_find_socket_byname(net, sunname, len, type, hash); |
1da177e4 LT |
282 | if (s) |
283 | sock_hold(s); | |
fbe9cc4a | 284 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
285 | return s; |
286 | } | |
287 | ||
6616f788 | 288 | static struct sock *unix_find_socket_byinode(struct inode *i) |
1da177e4 LT |
289 | { |
290 | struct sock *s; | |
291 | struct hlist_node *node; | |
292 | ||
fbe9cc4a | 293 | spin_lock(&unix_table_lock); |
1da177e4 LT |
294 | sk_for_each(s, node, |
295 | &unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) { | |
296 | struct dentry *dentry = unix_sk(s)->dentry; | |
297 | ||
6eba6a37 | 298 | if (dentry && dentry->d_inode == i) { |
1da177e4 LT |
299 | sock_hold(s); |
300 | goto found; | |
301 | } | |
302 | } | |
303 | s = NULL; | |
304 | found: | |
fbe9cc4a | 305 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
306 | return s; |
307 | } | |
308 | ||
309 | static inline int unix_writable(struct sock *sk) | |
310 | { | |
311 | return (atomic_read(&sk->sk_wmem_alloc) << 2) <= sk->sk_sndbuf; | |
312 | } | |
313 | ||
314 | static void unix_write_space(struct sock *sk) | |
315 | { | |
43815482 ED |
316 | struct socket_wq *wq; |
317 | ||
318 | rcu_read_lock(); | |
1da177e4 | 319 | if (unix_writable(sk)) { |
43815482 ED |
320 | wq = rcu_dereference(sk->sk_wq); |
321 | if (wq_has_sleeper(wq)) | |
67426b75 ED |
322 | wake_up_interruptible_sync_poll(&wq->wait, |
323 | POLLOUT | POLLWRNORM | POLLWRBAND); | |
8d8ad9d7 | 324 | sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); |
1da177e4 | 325 | } |
43815482 | 326 | rcu_read_unlock(); |
1da177e4 LT |
327 | } |
328 | ||
329 | /* When dgram socket disconnects (or changes its peer), we clear its receive | |
330 | * queue of packets arrived from previous peer. First, it allows to do | |
331 | * flow control based only on wmem_alloc; second, sk connected to peer | |
332 | * may receive messages only from that peer. */ | |
333 | static void unix_dgram_disconnected(struct sock *sk, struct sock *other) | |
334 | { | |
b03efcfb | 335 | if (!skb_queue_empty(&sk->sk_receive_queue)) { |
1da177e4 LT |
336 | skb_queue_purge(&sk->sk_receive_queue); |
337 | wake_up_interruptible_all(&unix_sk(sk)->peer_wait); | |
338 | ||
339 | /* If one link of bidirectional dgram pipe is disconnected, | |
340 | * we signal error. Messages are lost. Do not make this, | |
341 | * when peer was not connected to us. | |
342 | */ | |
343 | if (!sock_flag(other, SOCK_DEAD) && unix_peer(other) == sk) { | |
344 | other->sk_err = ECONNRESET; | |
345 | other->sk_error_report(other); | |
346 | } | |
347 | } | |
348 | } | |
349 | ||
350 | static void unix_sock_destructor(struct sock *sk) | |
351 | { | |
352 | struct unix_sock *u = unix_sk(sk); | |
353 | ||
354 | skb_queue_purge(&sk->sk_receive_queue); | |
355 | ||
547b792c IJ |
356 | WARN_ON(atomic_read(&sk->sk_wmem_alloc)); |
357 | WARN_ON(!sk_unhashed(sk)); | |
358 | WARN_ON(sk->sk_socket); | |
1da177e4 | 359 | if (!sock_flag(sk, SOCK_DEAD)) { |
6b41e7dd | 360 | printk(KERN_INFO "Attempt to release alive unix socket: %p\n", sk); |
1da177e4 LT |
361 | return; |
362 | } | |
363 | ||
364 | if (u->addr) | |
365 | unix_release_addr(u->addr); | |
366 | ||
518de9b3 | 367 | atomic_long_dec(&unix_nr_socks); |
6f756a8c | 368 | local_bh_disable(); |
a8076d8d | 369 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); |
6f756a8c | 370 | local_bh_enable(); |
1da177e4 | 371 | #ifdef UNIX_REFCNT_DEBUG |
518de9b3 ED |
372 | printk(KERN_DEBUG "UNIX %p is destroyed, %ld are still alive.\n", sk, |
373 | atomic_long_read(&unix_nr_socks)); | |
1da177e4 LT |
374 | #endif |
375 | } | |
376 | ||
6eba6a37 | 377 | static int unix_release_sock(struct sock *sk, int embrion) |
1da177e4 LT |
378 | { |
379 | struct unix_sock *u = unix_sk(sk); | |
380 | struct dentry *dentry; | |
381 | struct vfsmount *mnt; | |
382 | struct sock *skpair; | |
383 | struct sk_buff *skb; | |
384 | int state; | |
385 | ||
386 | unix_remove_socket(sk); | |
387 | ||
388 | /* Clear state */ | |
1c92b4e5 | 389 | unix_state_lock(sk); |
1da177e4 LT |
390 | sock_orphan(sk); |
391 | sk->sk_shutdown = SHUTDOWN_MASK; | |
392 | dentry = u->dentry; | |
393 | u->dentry = NULL; | |
394 | mnt = u->mnt; | |
395 | u->mnt = NULL; | |
396 | state = sk->sk_state; | |
397 | sk->sk_state = TCP_CLOSE; | |
1c92b4e5 | 398 | unix_state_unlock(sk); |
1da177e4 LT |
399 | |
400 | wake_up_interruptible_all(&u->peer_wait); | |
401 | ||
e27dfcea | 402 | skpair = unix_peer(sk); |
1da177e4 | 403 | |
e27dfcea | 404 | if (skpair != NULL) { |
1da177e4 | 405 | if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) { |
1c92b4e5 | 406 | unix_state_lock(skpair); |
1da177e4 LT |
407 | /* No more writes */ |
408 | skpair->sk_shutdown = SHUTDOWN_MASK; | |
409 | if (!skb_queue_empty(&sk->sk_receive_queue) || embrion) | |
410 | skpair->sk_err = ECONNRESET; | |
1c92b4e5 | 411 | unix_state_unlock(skpair); |
1da177e4 | 412 | skpair->sk_state_change(skpair); |
8d8ad9d7 | 413 | sk_wake_async(skpair, SOCK_WAKE_WAITD, POLL_HUP); |
1da177e4 LT |
414 | } |
415 | sock_put(skpair); /* It may now die */ | |
416 | unix_peer(sk) = NULL; | |
417 | } | |
418 | ||
419 | /* Try to flush out this socket. Throw out buffers at least */ | |
420 | ||
421 | while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) { | |
e27dfcea | 422 | if (state == TCP_LISTEN) |
1da177e4 LT |
423 | unix_release_sock(skb->sk, 1); |
424 | /* passed fds are erased in the kfree_skb hook */ | |
425 | kfree_skb(skb); | |
426 | } | |
427 | ||
428 | if (dentry) { | |
429 | dput(dentry); | |
430 | mntput(mnt); | |
431 | } | |
432 | ||
433 | sock_put(sk); | |
434 | ||
435 | /* ---- Socket is dead now and most probably destroyed ---- */ | |
436 | ||
437 | /* | |
438 | * Fixme: BSD difference: In BSD all sockets connected to use get | |
439 | * ECONNRESET and we die on the spot. In Linux we behave | |
440 | * like files and pipes do and wait for the last | |
441 | * dereference. | |
442 | * | |
443 | * Can't we simply set sock->err? | |
444 | * | |
445 | * What the above comment does talk about? --ANK(980817) | |
446 | */ | |
447 | ||
9305cfa4 | 448 | if (unix_tot_inflight) |
ac7bfa62 | 449 | unix_gc(); /* Garbage collect fds */ |
1da177e4 LT |
450 | |
451 | return 0; | |
452 | } | |
453 | ||
109f6e39 EB |
454 | static void init_peercred(struct sock *sk) |
455 | { | |
456 | put_pid(sk->sk_peer_pid); | |
457 | if (sk->sk_peer_cred) | |
458 | put_cred(sk->sk_peer_cred); | |
459 | sk->sk_peer_pid = get_pid(task_tgid(current)); | |
460 | sk->sk_peer_cred = get_current_cred(); | |
461 | } | |
462 | ||
463 | static void copy_peercred(struct sock *sk, struct sock *peersk) | |
464 | { | |
465 | put_pid(sk->sk_peer_pid); | |
466 | if (sk->sk_peer_cred) | |
467 | put_cred(sk->sk_peer_cred); | |
468 | sk->sk_peer_pid = get_pid(peersk->sk_peer_pid); | |
469 | sk->sk_peer_cred = get_cred(peersk->sk_peer_cred); | |
470 | } | |
471 | ||
1da177e4 LT |
472 | static int unix_listen(struct socket *sock, int backlog) |
473 | { | |
474 | int err; | |
475 | struct sock *sk = sock->sk; | |
476 | struct unix_sock *u = unix_sk(sk); | |
109f6e39 EB |
477 | struct pid *old_pid = NULL; |
478 | const struct cred *old_cred = NULL; | |
1da177e4 LT |
479 | |
480 | err = -EOPNOTSUPP; | |
6eba6a37 ED |
481 | if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET) |
482 | goto out; /* Only stream/seqpacket sockets accept */ | |
1da177e4 LT |
483 | err = -EINVAL; |
484 | if (!u->addr) | |
6eba6a37 | 485 | goto out; /* No listens on an unbound socket */ |
1c92b4e5 | 486 | unix_state_lock(sk); |
1da177e4 LT |
487 | if (sk->sk_state != TCP_CLOSE && sk->sk_state != TCP_LISTEN) |
488 | goto out_unlock; | |
489 | if (backlog > sk->sk_max_ack_backlog) | |
490 | wake_up_interruptible_all(&u->peer_wait); | |
491 | sk->sk_max_ack_backlog = backlog; | |
492 | sk->sk_state = TCP_LISTEN; | |
493 | /* set credentials so connect can copy them */ | |
109f6e39 | 494 | init_peercred(sk); |
1da177e4 LT |
495 | err = 0; |
496 | ||
497 | out_unlock: | |
1c92b4e5 | 498 | unix_state_unlock(sk); |
109f6e39 EB |
499 | put_pid(old_pid); |
500 | if (old_cred) | |
501 | put_cred(old_cred); | |
1da177e4 LT |
502 | out: |
503 | return err; | |
504 | } | |
505 | ||
506 | static int unix_release(struct socket *); | |
507 | static int unix_bind(struct socket *, struct sockaddr *, int); | |
508 | static int unix_stream_connect(struct socket *, struct sockaddr *, | |
509 | int addr_len, int flags); | |
510 | static int unix_socketpair(struct socket *, struct socket *); | |
511 | static int unix_accept(struct socket *, struct socket *, int); | |
512 | static int unix_getname(struct socket *, struct sockaddr *, int *, int); | |
513 | static unsigned int unix_poll(struct file *, struct socket *, poll_table *); | |
ec0d215f RW |
514 | static unsigned int unix_dgram_poll(struct file *, struct socket *, |
515 | poll_table *); | |
1da177e4 LT |
516 | static int unix_ioctl(struct socket *, unsigned int, unsigned long); |
517 | static int unix_shutdown(struct socket *, int); | |
518 | static int unix_stream_sendmsg(struct kiocb *, struct socket *, | |
519 | struct msghdr *, size_t); | |
520 | static int unix_stream_recvmsg(struct kiocb *, struct socket *, | |
521 | struct msghdr *, size_t, int); | |
522 | static int unix_dgram_sendmsg(struct kiocb *, struct socket *, | |
523 | struct msghdr *, size_t); | |
524 | static int unix_dgram_recvmsg(struct kiocb *, struct socket *, | |
525 | struct msghdr *, size_t, int); | |
526 | static int unix_dgram_connect(struct socket *, struct sockaddr *, | |
527 | int, int); | |
528 | static int unix_seqpacket_sendmsg(struct kiocb *, struct socket *, | |
529 | struct msghdr *, size_t); | |
a05d2ad1 EB |
530 | static int unix_seqpacket_recvmsg(struct kiocb *, struct socket *, |
531 | struct msghdr *, size_t, int); | |
1da177e4 | 532 | |
f55bb7f9 PE |
533 | static void unix_set_peek_off(struct sock *sk, int val) |
534 | { | |
535 | struct unix_sock *u = unix_sk(sk); | |
536 | ||
537 | mutex_lock(&u->readlock); | |
538 | sk->sk_peek_off = val; | |
539 | mutex_unlock(&u->readlock); | |
540 | } | |
541 | ||
542 | ||
90ddc4f0 | 543 | static const struct proto_ops unix_stream_ops = { |
1da177e4 LT |
544 | .family = PF_UNIX, |
545 | .owner = THIS_MODULE, | |
546 | .release = unix_release, | |
547 | .bind = unix_bind, | |
548 | .connect = unix_stream_connect, | |
549 | .socketpair = unix_socketpair, | |
550 | .accept = unix_accept, | |
551 | .getname = unix_getname, | |
552 | .poll = unix_poll, | |
553 | .ioctl = unix_ioctl, | |
554 | .listen = unix_listen, | |
555 | .shutdown = unix_shutdown, | |
556 | .setsockopt = sock_no_setsockopt, | |
557 | .getsockopt = sock_no_getsockopt, | |
558 | .sendmsg = unix_stream_sendmsg, | |
559 | .recvmsg = unix_stream_recvmsg, | |
560 | .mmap = sock_no_mmap, | |
561 | .sendpage = sock_no_sendpage, | |
fc0d7536 | 562 | .set_peek_off = unix_set_peek_off, |
1da177e4 LT |
563 | }; |
564 | ||
90ddc4f0 | 565 | static const struct proto_ops unix_dgram_ops = { |
1da177e4 LT |
566 | .family = PF_UNIX, |
567 | .owner = THIS_MODULE, | |
568 | .release = unix_release, | |
569 | .bind = unix_bind, | |
570 | .connect = unix_dgram_connect, | |
571 | .socketpair = unix_socketpair, | |
572 | .accept = sock_no_accept, | |
573 | .getname = unix_getname, | |
ec0d215f | 574 | .poll = unix_dgram_poll, |
1da177e4 LT |
575 | .ioctl = unix_ioctl, |
576 | .listen = sock_no_listen, | |
577 | .shutdown = unix_shutdown, | |
578 | .setsockopt = sock_no_setsockopt, | |
579 | .getsockopt = sock_no_getsockopt, | |
580 | .sendmsg = unix_dgram_sendmsg, | |
581 | .recvmsg = unix_dgram_recvmsg, | |
582 | .mmap = sock_no_mmap, | |
583 | .sendpage = sock_no_sendpage, | |
f55bb7f9 | 584 | .set_peek_off = unix_set_peek_off, |
1da177e4 LT |
585 | }; |
586 | ||
90ddc4f0 | 587 | static const struct proto_ops unix_seqpacket_ops = { |
1da177e4 LT |
588 | .family = PF_UNIX, |
589 | .owner = THIS_MODULE, | |
590 | .release = unix_release, | |
591 | .bind = unix_bind, | |
592 | .connect = unix_stream_connect, | |
593 | .socketpair = unix_socketpair, | |
594 | .accept = unix_accept, | |
595 | .getname = unix_getname, | |
ec0d215f | 596 | .poll = unix_dgram_poll, |
1da177e4 LT |
597 | .ioctl = unix_ioctl, |
598 | .listen = unix_listen, | |
599 | .shutdown = unix_shutdown, | |
600 | .setsockopt = sock_no_setsockopt, | |
601 | .getsockopt = sock_no_getsockopt, | |
602 | .sendmsg = unix_seqpacket_sendmsg, | |
a05d2ad1 | 603 | .recvmsg = unix_seqpacket_recvmsg, |
1da177e4 LT |
604 | .mmap = sock_no_mmap, |
605 | .sendpage = sock_no_sendpage, | |
f55bb7f9 | 606 | .set_peek_off = unix_set_peek_off, |
1da177e4 LT |
607 | }; |
608 | ||
609 | static struct proto unix_proto = { | |
248969ae ED |
610 | .name = "UNIX", |
611 | .owner = THIS_MODULE, | |
248969ae | 612 | .obj_size = sizeof(struct unix_sock), |
1da177e4 LT |
613 | }; |
614 | ||
a09785a2 IM |
615 | /* |
616 | * AF_UNIX sockets do not interact with hardware, hence they | |
617 | * dont trigger interrupts - so it's safe for them to have | |
618 | * bh-unsafe locking for their sk_receive_queue.lock. Split off | |
619 | * this special lock-class by reinitializing the spinlock key: | |
620 | */ | |
621 | static struct lock_class_key af_unix_sk_receive_queue_lock_key; | |
622 | ||
6eba6a37 | 623 | static struct sock *unix_create1(struct net *net, struct socket *sock) |
1da177e4 LT |
624 | { |
625 | struct sock *sk = NULL; | |
626 | struct unix_sock *u; | |
627 | ||
518de9b3 ED |
628 | atomic_long_inc(&unix_nr_socks); |
629 | if (atomic_long_read(&unix_nr_socks) > 2 * get_max_files()) | |
1da177e4 LT |
630 | goto out; |
631 | ||
6257ff21 | 632 | sk = sk_alloc(net, PF_UNIX, GFP_KERNEL, &unix_proto); |
1da177e4 LT |
633 | if (!sk) |
634 | goto out; | |
635 | ||
6eba6a37 | 636 | sock_init_data(sock, sk); |
a09785a2 IM |
637 | lockdep_set_class(&sk->sk_receive_queue.lock, |
638 | &af_unix_sk_receive_queue_lock_key); | |
1da177e4 LT |
639 | |
640 | sk->sk_write_space = unix_write_space; | |
a0a53c8b | 641 | sk->sk_max_ack_backlog = net->unx.sysctl_max_dgram_qlen; |
1da177e4 LT |
642 | sk->sk_destruct = unix_sock_destructor; |
643 | u = unix_sk(sk); | |
644 | u->dentry = NULL; | |
645 | u->mnt = NULL; | |
fd19f329 | 646 | spin_lock_init(&u->lock); |
516e0cc5 | 647 | atomic_long_set(&u->inflight, 0); |
1fd05ba5 | 648 | INIT_LIST_HEAD(&u->link); |
57b47a53 | 649 | mutex_init(&u->readlock); /* single task reading lock */ |
1da177e4 LT |
650 | init_waitqueue_head(&u->peer_wait); |
651 | unix_insert_socket(unix_sockets_unbound, sk); | |
652 | out: | |
284b327b | 653 | if (sk == NULL) |
518de9b3 | 654 | atomic_long_dec(&unix_nr_socks); |
920de804 ED |
655 | else { |
656 | local_bh_disable(); | |
a8076d8d | 657 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); |
920de804 ED |
658 | local_bh_enable(); |
659 | } | |
1da177e4 LT |
660 | return sk; |
661 | } | |
662 | ||
3f378b68 EP |
663 | static int unix_create(struct net *net, struct socket *sock, int protocol, |
664 | int kern) | |
1da177e4 LT |
665 | { |
666 | if (protocol && protocol != PF_UNIX) | |
667 | return -EPROTONOSUPPORT; | |
668 | ||
669 | sock->state = SS_UNCONNECTED; | |
670 | ||
671 | switch (sock->type) { | |
672 | case SOCK_STREAM: | |
673 | sock->ops = &unix_stream_ops; | |
674 | break; | |
675 | /* | |
676 | * Believe it or not BSD has AF_UNIX, SOCK_RAW though | |
677 | * nothing uses it. | |
678 | */ | |
679 | case SOCK_RAW: | |
e27dfcea | 680 | sock->type = SOCK_DGRAM; |
1da177e4 LT |
681 | case SOCK_DGRAM: |
682 | sock->ops = &unix_dgram_ops; | |
683 | break; | |
684 | case SOCK_SEQPACKET: | |
685 | sock->ops = &unix_seqpacket_ops; | |
686 | break; | |
687 | default: | |
688 | return -ESOCKTNOSUPPORT; | |
689 | } | |
690 | ||
1b8d7ae4 | 691 | return unix_create1(net, sock) ? 0 : -ENOMEM; |
1da177e4 LT |
692 | } |
693 | ||
694 | static int unix_release(struct socket *sock) | |
695 | { | |
696 | struct sock *sk = sock->sk; | |
697 | ||
698 | if (!sk) | |
699 | return 0; | |
700 | ||
701 | sock->sk = NULL; | |
702 | ||
6eba6a37 | 703 | return unix_release_sock(sk, 0); |
1da177e4 LT |
704 | } |
705 | ||
706 | static int unix_autobind(struct socket *sock) | |
707 | { | |
708 | struct sock *sk = sock->sk; | |
3b1e0a65 | 709 | struct net *net = sock_net(sk); |
1da177e4 LT |
710 | struct unix_sock *u = unix_sk(sk); |
711 | static u32 ordernum = 1; | |
6eba6a37 | 712 | struct unix_address *addr; |
1da177e4 | 713 | int err; |
8df73ff9 | 714 | unsigned int retries = 0; |
1da177e4 | 715 | |
57b47a53 | 716 | mutex_lock(&u->readlock); |
1da177e4 LT |
717 | |
718 | err = 0; | |
719 | if (u->addr) | |
720 | goto out; | |
721 | ||
722 | err = -ENOMEM; | |
0da974f4 | 723 | addr = kzalloc(sizeof(*addr) + sizeof(short) + 16, GFP_KERNEL); |
1da177e4 LT |
724 | if (!addr) |
725 | goto out; | |
726 | ||
1da177e4 LT |
727 | addr->name->sun_family = AF_UNIX; |
728 | atomic_set(&addr->refcnt, 1); | |
729 | ||
730 | retry: | |
731 | addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + sizeof(short); | |
07f0757a | 732 | addr->hash = unix_hash_fold(csum_partial(addr->name, addr->len, 0)); |
1da177e4 | 733 | |
fbe9cc4a | 734 | spin_lock(&unix_table_lock); |
1da177e4 LT |
735 | ordernum = (ordernum+1)&0xFFFFF; |
736 | ||
097e66c5 | 737 | if (__unix_find_socket_byname(net, addr->name, addr->len, sock->type, |
1da177e4 | 738 | addr->hash)) { |
fbe9cc4a | 739 | spin_unlock(&unix_table_lock); |
8df73ff9 TH |
740 | /* |
741 | * __unix_find_socket_byname() may take long time if many names | |
742 | * are already in use. | |
743 | */ | |
744 | cond_resched(); | |
745 | /* Give up if all names seems to be in use. */ | |
746 | if (retries++ == 0xFFFFF) { | |
747 | err = -ENOSPC; | |
748 | kfree(addr); | |
749 | goto out; | |
750 | } | |
1da177e4 LT |
751 | goto retry; |
752 | } | |
753 | addr->hash ^= sk->sk_type; | |
754 | ||
755 | __unix_remove_socket(sk); | |
756 | u->addr = addr; | |
757 | __unix_insert_socket(&unix_socket_table[addr->hash], sk); | |
fbe9cc4a | 758 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
759 | err = 0; |
760 | ||
57b47a53 | 761 | out: mutex_unlock(&u->readlock); |
1da177e4 LT |
762 | return err; |
763 | } | |
764 | ||
097e66c5 DL |
765 | static struct sock *unix_find_other(struct net *net, |
766 | struct sockaddr_un *sunname, int len, | |
1da177e4 LT |
767 | int type, unsigned hash, int *error) |
768 | { | |
769 | struct sock *u; | |
421748ec | 770 | struct path path; |
1da177e4 | 771 | int err = 0; |
ac7bfa62 | 772 | |
1da177e4 | 773 | if (sunname->sun_path[0]) { |
421748ec AV |
774 | struct inode *inode; |
775 | err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, &path); | |
1da177e4 LT |
776 | if (err) |
777 | goto fail; | |
421748ec AV |
778 | inode = path.dentry->d_inode; |
779 | err = inode_permission(inode, MAY_WRITE); | |
1da177e4 LT |
780 | if (err) |
781 | goto put_fail; | |
782 | ||
783 | err = -ECONNREFUSED; | |
421748ec | 784 | if (!S_ISSOCK(inode->i_mode)) |
1da177e4 | 785 | goto put_fail; |
6616f788 | 786 | u = unix_find_socket_byinode(inode); |
1da177e4 LT |
787 | if (!u) |
788 | goto put_fail; | |
789 | ||
790 | if (u->sk_type == type) | |
421748ec | 791 | touch_atime(path.mnt, path.dentry); |
1da177e4 | 792 | |
421748ec | 793 | path_put(&path); |
1da177e4 | 794 | |
e27dfcea | 795 | err = -EPROTOTYPE; |
1da177e4 LT |
796 | if (u->sk_type != type) { |
797 | sock_put(u); | |
798 | goto fail; | |
799 | } | |
800 | } else { | |
801 | err = -ECONNREFUSED; | |
e27dfcea | 802 | u = unix_find_socket_byname(net, sunname, len, type, hash); |
1da177e4 LT |
803 | if (u) { |
804 | struct dentry *dentry; | |
805 | dentry = unix_sk(u)->dentry; | |
806 | if (dentry) | |
807 | touch_atime(unix_sk(u)->mnt, dentry); | |
808 | } else | |
809 | goto fail; | |
810 | } | |
811 | return u; | |
812 | ||
813 | put_fail: | |
421748ec | 814 | path_put(&path); |
1da177e4 | 815 | fail: |
e27dfcea | 816 | *error = err; |
1da177e4 LT |
817 | return NULL; |
818 | } | |
819 | ||
820 | ||
821 | static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) | |
822 | { | |
823 | struct sock *sk = sock->sk; | |
3b1e0a65 | 824 | struct net *net = sock_net(sk); |
1da177e4 | 825 | struct unix_sock *u = unix_sk(sk); |
e27dfcea | 826 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr; |
dae6ad8f | 827 | char *sun_path = sunaddr->sun_path; |
6eba6a37 | 828 | struct dentry *dentry = NULL; |
dae6ad8f | 829 | struct path path; |
1da177e4 LT |
830 | int err; |
831 | unsigned hash; | |
832 | struct unix_address *addr; | |
833 | struct hlist_head *list; | |
834 | ||
835 | err = -EINVAL; | |
836 | if (sunaddr->sun_family != AF_UNIX) | |
837 | goto out; | |
838 | ||
e27dfcea | 839 | if (addr_len == sizeof(short)) { |
1da177e4 LT |
840 | err = unix_autobind(sock); |
841 | goto out; | |
842 | } | |
843 | ||
844 | err = unix_mkname(sunaddr, addr_len, &hash); | |
845 | if (err < 0) | |
846 | goto out; | |
847 | addr_len = err; | |
848 | ||
57b47a53 | 849 | mutex_lock(&u->readlock); |
1da177e4 LT |
850 | |
851 | err = -EINVAL; | |
852 | if (u->addr) | |
853 | goto out_up; | |
854 | ||
855 | err = -ENOMEM; | |
856 | addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL); | |
857 | if (!addr) | |
858 | goto out_up; | |
859 | ||
860 | memcpy(addr->name, sunaddr, addr_len); | |
861 | addr->len = addr_len; | |
862 | addr->hash = hash ^ sk->sk_type; | |
863 | atomic_set(&addr->refcnt, 1); | |
864 | ||
dae6ad8f | 865 | if (sun_path[0]) { |
04fc66e7 | 866 | umode_t mode; |
1da177e4 LT |
867 | err = 0; |
868 | /* | |
869 | * Get the parent directory, calculate the hash for last | |
870 | * component. | |
871 | */ | |
dae6ad8f | 872 | dentry = kern_path_create(AT_FDCWD, sun_path, &path, 0); |
1da177e4 LT |
873 | err = PTR_ERR(dentry); |
874 | if (IS_ERR(dentry)) | |
dae6ad8f | 875 | goto out_mknod_parent; |
f81a0bff | 876 | |
1da177e4 LT |
877 | /* |
878 | * All right, let's create it. | |
879 | */ | |
880 | mode = S_IFSOCK | | |
ce3b0f8d | 881 | (SOCK_INODE(sock)->i_mode & ~current_umask()); |
dae6ad8f | 882 | err = mnt_want_write(path.mnt); |
463c3197 DH |
883 | if (err) |
884 | goto out_mknod_dput; | |
dae6ad8f | 885 | err = security_path_mknod(&path, dentry, mode, 0); |
be6d3e56 KT |
886 | if (err) |
887 | goto out_mknod_drop_write; | |
dae6ad8f | 888 | err = vfs_mknod(path.dentry->d_inode, dentry, mode, 0); |
be6d3e56 | 889 | out_mknod_drop_write: |
dae6ad8f | 890 | mnt_drop_write(path.mnt); |
1da177e4 LT |
891 | if (err) |
892 | goto out_mknod_dput; | |
dae6ad8f AV |
893 | mutex_unlock(&path.dentry->d_inode->i_mutex); |
894 | dput(path.dentry); | |
895 | path.dentry = dentry; | |
1da177e4 LT |
896 | |
897 | addr->hash = UNIX_HASH_SIZE; | |
898 | } | |
899 | ||
fbe9cc4a | 900 | spin_lock(&unix_table_lock); |
1da177e4 | 901 | |
dae6ad8f | 902 | if (!sun_path[0]) { |
1da177e4 | 903 | err = -EADDRINUSE; |
097e66c5 | 904 | if (__unix_find_socket_byname(net, sunaddr, addr_len, |
1da177e4 LT |
905 | sk->sk_type, hash)) { |
906 | unix_release_addr(addr); | |
907 | goto out_unlock; | |
908 | } | |
909 | ||
910 | list = &unix_socket_table[addr->hash]; | |
911 | } else { | |
912 | list = &unix_socket_table[dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1)]; | |
dae6ad8f AV |
913 | u->dentry = path.dentry; |
914 | u->mnt = path.mnt; | |
1da177e4 LT |
915 | } |
916 | ||
917 | err = 0; | |
918 | __unix_remove_socket(sk); | |
919 | u->addr = addr; | |
920 | __unix_insert_socket(list, sk); | |
921 | ||
922 | out_unlock: | |
fbe9cc4a | 923 | spin_unlock(&unix_table_lock); |
1da177e4 | 924 | out_up: |
57b47a53 | 925 | mutex_unlock(&u->readlock); |
1da177e4 LT |
926 | out: |
927 | return err; | |
928 | ||
929 | out_mknod_dput: | |
930 | dput(dentry); | |
dae6ad8f AV |
931 | mutex_unlock(&path.dentry->d_inode->i_mutex); |
932 | path_put(&path); | |
1da177e4 | 933 | out_mknod_parent: |
e27dfcea JK |
934 | if (err == -EEXIST) |
935 | err = -EADDRINUSE; | |
1da177e4 LT |
936 | unix_release_addr(addr); |
937 | goto out_up; | |
938 | } | |
939 | ||
278a3de5 DM |
940 | static void unix_state_double_lock(struct sock *sk1, struct sock *sk2) |
941 | { | |
942 | if (unlikely(sk1 == sk2) || !sk2) { | |
943 | unix_state_lock(sk1); | |
944 | return; | |
945 | } | |
946 | if (sk1 < sk2) { | |
947 | unix_state_lock(sk1); | |
948 | unix_state_lock_nested(sk2); | |
949 | } else { | |
950 | unix_state_lock(sk2); | |
951 | unix_state_lock_nested(sk1); | |
952 | } | |
953 | } | |
954 | ||
955 | static void unix_state_double_unlock(struct sock *sk1, struct sock *sk2) | |
956 | { | |
957 | if (unlikely(sk1 == sk2) || !sk2) { | |
958 | unix_state_unlock(sk1); | |
959 | return; | |
960 | } | |
961 | unix_state_unlock(sk1); | |
962 | unix_state_unlock(sk2); | |
963 | } | |
964 | ||
1da177e4 LT |
965 | static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr, |
966 | int alen, int flags) | |
967 | { | |
968 | struct sock *sk = sock->sk; | |
3b1e0a65 | 969 | struct net *net = sock_net(sk); |
e27dfcea | 970 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)addr; |
1da177e4 LT |
971 | struct sock *other; |
972 | unsigned hash; | |
973 | int err; | |
974 | ||
975 | if (addr->sa_family != AF_UNSPEC) { | |
976 | err = unix_mkname(sunaddr, alen, &hash); | |
977 | if (err < 0) | |
978 | goto out; | |
979 | alen = err; | |
980 | ||
981 | if (test_bit(SOCK_PASSCRED, &sock->flags) && | |
982 | !unix_sk(sk)->addr && (err = unix_autobind(sock)) != 0) | |
983 | goto out; | |
984 | ||
278a3de5 | 985 | restart: |
e27dfcea | 986 | other = unix_find_other(net, sunaddr, alen, sock->type, hash, &err); |
1da177e4 LT |
987 | if (!other) |
988 | goto out; | |
989 | ||
278a3de5 DM |
990 | unix_state_double_lock(sk, other); |
991 | ||
992 | /* Apparently VFS overslept socket death. Retry. */ | |
993 | if (sock_flag(other, SOCK_DEAD)) { | |
994 | unix_state_double_unlock(sk, other); | |
995 | sock_put(other); | |
996 | goto restart; | |
997 | } | |
1da177e4 LT |
998 | |
999 | err = -EPERM; | |
1000 | if (!unix_may_send(sk, other)) | |
1001 | goto out_unlock; | |
1002 | ||
1003 | err = security_unix_may_send(sk->sk_socket, other->sk_socket); | |
1004 | if (err) | |
1005 | goto out_unlock; | |
1006 | ||
1007 | } else { | |
1008 | /* | |
1009 | * 1003.1g breaking connected state with AF_UNSPEC | |
1010 | */ | |
1011 | other = NULL; | |
278a3de5 | 1012 | unix_state_double_lock(sk, other); |
1da177e4 LT |
1013 | } |
1014 | ||
1015 | /* | |
1016 | * If it was connected, reconnect. | |
1017 | */ | |
1018 | if (unix_peer(sk)) { | |
1019 | struct sock *old_peer = unix_peer(sk); | |
e27dfcea | 1020 | unix_peer(sk) = other; |
278a3de5 | 1021 | unix_state_double_unlock(sk, other); |
1da177e4 LT |
1022 | |
1023 | if (other != old_peer) | |
1024 | unix_dgram_disconnected(sk, old_peer); | |
1025 | sock_put(old_peer); | |
1026 | } else { | |
e27dfcea | 1027 | unix_peer(sk) = other; |
278a3de5 | 1028 | unix_state_double_unlock(sk, other); |
1da177e4 | 1029 | } |
ac7bfa62 | 1030 | return 0; |
1da177e4 LT |
1031 | |
1032 | out_unlock: | |
278a3de5 | 1033 | unix_state_double_unlock(sk, other); |
1da177e4 LT |
1034 | sock_put(other); |
1035 | out: | |
1036 | return err; | |
1037 | } | |
1038 | ||
1039 | static long unix_wait_for_peer(struct sock *other, long timeo) | |
1040 | { | |
1041 | struct unix_sock *u = unix_sk(other); | |
1042 | int sched; | |
1043 | DEFINE_WAIT(wait); | |
1044 | ||
1045 | prepare_to_wait_exclusive(&u->peer_wait, &wait, TASK_INTERRUPTIBLE); | |
1046 | ||
1047 | sched = !sock_flag(other, SOCK_DEAD) && | |
1048 | !(other->sk_shutdown & RCV_SHUTDOWN) && | |
3c73419c | 1049 | unix_recvq_full(other); |
1da177e4 | 1050 | |
1c92b4e5 | 1051 | unix_state_unlock(other); |
1da177e4 LT |
1052 | |
1053 | if (sched) | |
1054 | timeo = schedule_timeout(timeo); | |
1055 | ||
1056 | finish_wait(&u->peer_wait, &wait); | |
1057 | return timeo; | |
1058 | } | |
1059 | ||
1060 | static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr, | |
1061 | int addr_len, int flags) | |
1062 | { | |
e27dfcea | 1063 | struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr; |
1da177e4 | 1064 | struct sock *sk = sock->sk; |
3b1e0a65 | 1065 | struct net *net = sock_net(sk); |
1da177e4 LT |
1066 | struct unix_sock *u = unix_sk(sk), *newu, *otheru; |
1067 | struct sock *newsk = NULL; | |
1068 | struct sock *other = NULL; | |
1069 | struct sk_buff *skb = NULL; | |
1070 | unsigned hash; | |
1071 | int st; | |
1072 | int err; | |
1073 | long timeo; | |
1074 | ||
1075 | err = unix_mkname(sunaddr, addr_len, &hash); | |
1076 | if (err < 0) | |
1077 | goto out; | |
1078 | addr_len = err; | |
1079 | ||
f64f9e71 JP |
1080 | if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr && |
1081 | (err = unix_autobind(sock)) != 0) | |
1da177e4 LT |
1082 | goto out; |
1083 | ||
1084 | timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); | |
1085 | ||
1086 | /* First of all allocate resources. | |
1087 | If we will make it after state is locked, | |
1088 | we will have to recheck all again in any case. | |
1089 | */ | |
1090 | ||
1091 | err = -ENOMEM; | |
1092 | ||
1093 | /* create new sock for complete connection */ | |
3b1e0a65 | 1094 | newsk = unix_create1(sock_net(sk), NULL); |
1da177e4 LT |
1095 | if (newsk == NULL) |
1096 | goto out; | |
1097 | ||
1098 | /* Allocate skb for sending to listening sock */ | |
1099 | skb = sock_wmalloc(newsk, 1, 0, GFP_KERNEL); | |
1100 | if (skb == NULL) | |
1101 | goto out; | |
1102 | ||
1103 | restart: | |
1104 | /* Find listening sock. */ | |
097e66c5 | 1105 | other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, hash, &err); |
1da177e4 LT |
1106 | if (!other) |
1107 | goto out; | |
1108 | ||
1109 | /* Latch state of peer */ | |
1c92b4e5 | 1110 | unix_state_lock(other); |
1da177e4 LT |
1111 | |
1112 | /* Apparently VFS overslept socket death. Retry. */ | |
1113 | if (sock_flag(other, SOCK_DEAD)) { | |
1c92b4e5 | 1114 | unix_state_unlock(other); |
1da177e4 LT |
1115 | sock_put(other); |
1116 | goto restart; | |
1117 | } | |
1118 | ||
1119 | err = -ECONNREFUSED; | |
1120 | if (other->sk_state != TCP_LISTEN) | |
1121 | goto out_unlock; | |
77238f2b TS |
1122 | if (other->sk_shutdown & RCV_SHUTDOWN) |
1123 | goto out_unlock; | |
1da177e4 | 1124 | |
3c73419c | 1125 | if (unix_recvq_full(other)) { |
1da177e4 LT |
1126 | err = -EAGAIN; |
1127 | if (!timeo) | |
1128 | goto out_unlock; | |
1129 | ||
1130 | timeo = unix_wait_for_peer(other, timeo); | |
1131 | ||
1132 | err = sock_intr_errno(timeo); | |
1133 | if (signal_pending(current)) | |
1134 | goto out; | |
1135 | sock_put(other); | |
1136 | goto restart; | |
ac7bfa62 | 1137 | } |
1da177e4 LT |
1138 | |
1139 | /* Latch our state. | |
1140 | ||
e5537bfc | 1141 | It is tricky place. We need to grab our state lock and cannot |
1da177e4 LT |
1142 | drop lock on peer. It is dangerous because deadlock is |
1143 | possible. Connect to self case and simultaneous | |
1144 | attempt to connect are eliminated by checking socket | |
1145 | state. other is TCP_LISTEN, if sk is TCP_LISTEN we | |
1146 | check this before attempt to grab lock. | |
1147 | ||
1148 | Well, and we have to recheck the state after socket locked. | |
1149 | */ | |
1150 | st = sk->sk_state; | |
1151 | ||
1152 | switch (st) { | |
1153 | case TCP_CLOSE: | |
1154 | /* This is ok... continue with connect */ | |
1155 | break; | |
1156 | case TCP_ESTABLISHED: | |
1157 | /* Socket is already connected */ | |
1158 | err = -EISCONN; | |
1159 | goto out_unlock; | |
1160 | default: | |
1161 | err = -EINVAL; | |
1162 | goto out_unlock; | |
1163 | } | |
1164 | ||
1c92b4e5 | 1165 | unix_state_lock_nested(sk); |
1da177e4 LT |
1166 | |
1167 | if (sk->sk_state != st) { | |
1c92b4e5 DM |
1168 | unix_state_unlock(sk); |
1169 | unix_state_unlock(other); | |
1da177e4 LT |
1170 | sock_put(other); |
1171 | goto restart; | |
1172 | } | |
1173 | ||
3610cda5 | 1174 | err = security_unix_stream_connect(sk, other, newsk); |
1da177e4 | 1175 | if (err) { |
1c92b4e5 | 1176 | unix_state_unlock(sk); |
1da177e4 LT |
1177 | goto out_unlock; |
1178 | } | |
1179 | ||
1180 | /* The way is open! Fastly set all the necessary fields... */ | |
1181 | ||
1182 | sock_hold(sk); | |
1183 | unix_peer(newsk) = sk; | |
1184 | newsk->sk_state = TCP_ESTABLISHED; | |
1185 | newsk->sk_type = sk->sk_type; | |
109f6e39 | 1186 | init_peercred(newsk); |
1da177e4 | 1187 | newu = unix_sk(newsk); |
eaefd110 | 1188 | RCU_INIT_POINTER(newsk->sk_wq, &newu->peer_wq); |
1da177e4 LT |
1189 | otheru = unix_sk(other); |
1190 | ||
1191 | /* copy address information from listening to new sock*/ | |
1192 | if (otheru->addr) { | |
1193 | atomic_inc(&otheru->addr->refcnt); | |
1194 | newu->addr = otheru->addr; | |
1195 | } | |
1196 | if (otheru->dentry) { | |
1197 | newu->dentry = dget(otheru->dentry); | |
1198 | newu->mnt = mntget(otheru->mnt); | |
1199 | } | |
1200 | ||
1201 | /* Set credentials */ | |
109f6e39 | 1202 | copy_peercred(sk, other); |
1da177e4 | 1203 | |
1da177e4 LT |
1204 | sock->state = SS_CONNECTED; |
1205 | sk->sk_state = TCP_ESTABLISHED; | |
830a1e5c BL |
1206 | sock_hold(newsk); |
1207 | ||
1208 | smp_mb__after_atomic_inc(); /* sock_hold() does an atomic_inc() */ | |
1209 | unix_peer(sk) = newsk; | |
1da177e4 | 1210 | |
1c92b4e5 | 1211 | unix_state_unlock(sk); |
1da177e4 LT |
1212 | |
1213 | /* take ten and and send info to listening sock */ | |
1214 | spin_lock(&other->sk_receive_queue.lock); | |
1215 | __skb_queue_tail(&other->sk_receive_queue, skb); | |
1da177e4 | 1216 | spin_unlock(&other->sk_receive_queue.lock); |
1c92b4e5 | 1217 | unix_state_unlock(other); |
1da177e4 LT |
1218 | other->sk_data_ready(other, 0); |
1219 | sock_put(other); | |
1220 | return 0; | |
1221 | ||
1222 | out_unlock: | |
1223 | if (other) | |
1c92b4e5 | 1224 | unix_state_unlock(other); |
1da177e4 LT |
1225 | |
1226 | out: | |
40d44446 | 1227 | kfree_skb(skb); |
1da177e4 LT |
1228 | if (newsk) |
1229 | unix_release_sock(newsk, 0); | |
1230 | if (other) | |
1231 | sock_put(other); | |
1232 | return err; | |
1233 | } | |
1234 | ||
1235 | static int unix_socketpair(struct socket *socka, struct socket *sockb) | |
1236 | { | |
e27dfcea | 1237 | struct sock *ska = socka->sk, *skb = sockb->sk; |
1da177e4 LT |
1238 | |
1239 | /* Join our sockets back to back */ | |
1240 | sock_hold(ska); | |
1241 | sock_hold(skb); | |
e27dfcea JK |
1242 | unix_peer(ska) = skb; |
1243 | unix_peer(skb) = ska; | |
109f6e39 EB |
1244 | init_peercred(ska); |
1245 | init_peercred(skb); | |
1da177e4 LT |
1246 | |
1247 | if (ska->sk_type != SOCK_DGRAM) { | |
1248 | ska->sk_state = TCP_ESTABLISHED; | |
1249 | skb->sk_state = TCP_ESTABLISHED; | |
1250 | socka->state = SS_CONNECTED; | |
1251 | sockb->state = SS_CONNECTED; | |
1252 | } | |
1253 | return 0; | |
1254 | } | |
1255 | ||
1256 | static int unix_accept(struct socket *sock, struct socket *newsock, int flags) | |
1257 | { | |
1258 | struct sock *sk = sock->sk; | |
1259 | struct sock *tsk; | |
1260 | struct sk_buff *skb; | |
1261 | int err; | |
1262 | ||
1263 | err = -EOPNOTSUPP; | |
6eba6a37 | 1264 | if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET) |
1da177e4 LT |
1265 | goto out; |
1266 | ||
1267 | err = -EINVAL; | |
1268 | if (sk->sk_state != TCP_LISTEN) | |
1269 | goto out; | |
1270 | ||
1271 | /* If socket state is TCP_LISTEN it cannot change (for now...), | |
1272 | * so that no locks are necessary. | |
1273 | */ | |
1274 | ||
1275 | skb = skb_recv_datagram(sk, 0, flags&O_NONBLOCK, &err); | |
1276 | if (!skb) { | |
1277 | /* This means receive shutdown. */ | |
1278 | if (err == 0) | |
1279 | err = -EINVAL; | |
1280 | goto out; | |
1281 | } | |
1282 | ||
1283 | tsk = skb->sk; | |
1284 | skb_free_datagram(sk, skb); | |
1285 | wake_up_interruptible(&unix_sk(sk)->peer_wait); | |
1286 | ||
1287 | /* attach accepted sock to socket */ | |
1c92b4e5 | 1288 | unix_state_lock(tsk); |
1da177e4 LT |
1289 | newsock->state = SS_CONNECTED; |
1290 | sock_graft(tsk, newsock); | |
1c92b4e5 | 1291 | unix_state_unlock(tsk); |
1da177e4 LT |
1292 | return 0; |
1293 | ||
1294 | out: | |
1295 | return err; | |
1296 | } | |
1297 | ||
1298 | ||
1299 | static int unix_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len, int peer) | |
1300 | { | |
1301 | struct sock *sk = sock->sk; | |
1302 | struct unix_sock *u; | |
13cfa97b | 1303 | DECLARE_SOCKADDR(struct sockaddr_un *, sunaddr, uaddr); |
1da177e4 LT |
1304 | int err = 0; |
1305 | ||
1306 | if (peer) { | |
1307 | sk = unix_peer_get(sk); | |
1308 | ||
1309 | err = -ENOTCONN; | |
1310 | if (!sk) | |
1311 | goto out; | |
1312 | err = 0; | |
1313 | } else { | |
1314 | sock_hold(sk); | |
1315 | } | |
1316 | ||
1317 | u = unix_sk(sk); | |
1c92b4e5 | 1318 | unix_state_lock(sk); |
1da177e4 LT |
1319 | if (!u->addr) { |
1320 | sunaddr->sun_family = AF_UNIX; | |
1321 | sunaddr->sun_path[0] = 0; | |
1322 | *uaddr_len = sizeof(short); | |
1323 | } else { | |
1324 | struct unix_address *addr = u->addr; | |
1325 | ||
1326 | *uaddr_len = addr->len; | |
1327 | memcpy(sunaddr, addr->name, *uaddr_len); | |
1328 | } | |
1c92b4e5 | 1329 | unix_state_unlock(sk); |
1da177e4 LT |
1330 | sock_put(sk); |
1331 | out: | |
1332 | return err; | |
1333 | } | |
1334 | ||
1335 | static void unix_detach_fds(struct scm_cookie *scm, struct sk_buff *skb) | |
1336 | { | |
1337 | int i; | |
1338 | ||
1339 | scm->fp = UNIXCB(skb).fp; | |
1da177e4 LT |
1340 | UNIXCB(skb).fp = NULL; |
1341 | ||
6eba6a37 | 1342 | for (i = scm->fp->count-1; i >= 0; i--) |
1da177e4 LT |
1343 | unix_notinflight(scm->fp->fp[i]); |
1344 | } | |
1345 | ||
7361c36c | 1346 | static void unix_destruct_scm(struct sk_buff *skb) |
1da177e4 LT |
1347 | { |
1348 | struct scm_cookie scm; | |
1349 | memset(&scm, 0, sizeof(scm)); | |
7361c36c EB |
1350 | scm.pid = UNIXCB(skb).pid; |
1351 | scm.cred = UNIXCB(skb).cred; | |
1352 | if (UNIXCB(skb).fp) | |
1353 | unix_detach_fds(&scm, skb); | |
1da177e4 LT |
1354 | |
1355 | /* Alas, it calls VFS */ | |
1356 | /* So fscking what? fput() had been SMP-safe since the last Summer */ | |
1357 | scm_destroy(&scm); | |
1358 | sock_wfree(skb); | |
1359 | } | |
1360 | ||
25888e30 ED |
1361 | #define MAX_RECURSION_LEVEL 4 |
1362 | ||
6209344f | 1363 | static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb) |
1da177e4 LT |
1364 | { |
1365 | int i; | |
25888e30 ED |
1366 | unsigned char max_level = 0; |
1367 | int unix_sock_count = 0; | |
1368 | ||
1369 | for (i = scm->fp->count - 1; i >= 0; i--) { | |
1370 | struct sock *sk = unix_get_socket(scm->fp->fp[i]); | |
1371 | ||
1372 | if (sk) { | |
1373 | unix_sock_count++; | |
1374 | max_level = max(max_level, | |
1375 | unix_sk(sk)->recursion_level); | |
1376 | } | |
1377 | } | |
1378 | if (unlikely(max_level > MAX_RECURSION_LEVEL)) | |
1379 | return -ETOOMANYREFS; | |
6209344f MS |
1380 | |
1381 | /* | |
1382 | * Need to duplicate file references for the sake of garbage | |
1383 | * collection. Otherwise a socket in the fps might become a | |
1384 | * candidate for GC while the skb is not yet queued. | |
1385 | */ | |
1386 | UNIXCB(skb).fp = scm_fp_dup(scm->fp); | |
1387 | if (!UNIXCB(skb).fp) | |
1388 | return -ENOMEM; | |
1389 | ||
25888e30 ED |
1390 | if (unix_sock_count) { |
1391 | for (i = scm->fp->count - 1; i >= 0; i--) | |
1392 | unix_inflight(scm->fp->fp[i]); | |
1393 | } | |
1394 | return max_level; | |
1da177e4 LT |
1395 | } |
1396 | ||
f78a5fda | 1397 | static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool send_fds) |
7361c36c EB |
1398 | { |
1399 | int err = 0; | |
16e57262 | 1400 | |
f78a5fda | 1401 | UNIXCB(skb).pid = get_pid(scm->pid); |
16e57262 ED |
1402 | if (scm->cred) |
1403 | UNIXCB(skb).cred = get_cred(scm->cred); | |
7361c36c EB |
1404 | UNIXCB(skb).fp = NULL; |
1405 | if (scm->fp && send_fds) | |
1406 | err = unix_attach_fds(scm, skb); | |
1407 | ||
1408 | skb->destructor = unix_destruct_scm; | |
1409 | return err; | |
1410 | } | |
1411 | ||
16e57262 ED |
1412 | /* |
1413 | * Some apps rely on write() giving SCM_CREDENTIALS | |
1414 | * We include credentials if source or destination socket | |
1415 | * asserted SOCK_PASSCRED. | |
1416 | */ | |
1417 | static void maybe_add_creds(struct sk_buff *skb, const struct socket *sock, | |
1418 | const struct sock *other) | |
1419 | { | |
1420 | if (UNIXCB(skb).cred) | |
1421 | return; | |
1422 | if (test_bit(SOCK_PASSCRED, &sock->flags) || | |
1423 | !other->sk_socket || | |
1424 | test_bit(SOCK_PASSCRED, &other->sk_socket->flags)) { | |
1425 | UNIXCB(skb).pid = get_pid(task_tgid(current)); | |
1426 | UNIXCB(skb).cred = get_current_cred(); | |
1427 | } | |
1428 | } | |
1429 | ||
1da177e4 LT |
1430 | /* |
1431 | * Send AF_UNIX data. | |
1432 | */ | |
1433 | ||
1434 | static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, | |
1435 | struct msghdr *msg, size_t len) | |
1436 | { | |
1437 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1438 | struct sock *sk = sock->sk; | |
3b1e0a65 | 1439 | struct net *net = sock_net(sk); |
1da177e4 | 1440 | struct unix_sock *u = unix_sk(sk); |
e27dfcea | 1441 | struct sockaddr_un *sunaddr = msg->msg_name; |
1da177e4 LT |
1442 | struct sock *other = NULL; |
1443 | int namelen = 0; /* fake GCC */ | |
1444 | int err; | |
1445 | unsigned hash; | |
f78a5fda | 1446 | struct sk_buff *skb; |
1da177e4 LT |
1447 | long timeo; |
1448 | struct scm_cookie tmp_scm; | |
25888e30 | 1449 | int max_level; |
1da177e4 LT |
1450 | |
1451 | if (NULL == siocb->scm) | |
1452 | siocb->scm = &tmp_scm; | |
5f23b734 | 1453 | wait_for_unix_gc(); |
1da177e4 LT |
1454 | err = scm_send(sock, msg, siocb->scm); |
1455 | if (err < 0) | |
1456 | return err; | |
1457 | ||
1458 | err = -EOPNOTSUPP; | |
1459 | if (msg->msg_flags&MSG_OOB) | |
1460 | goto out; | |
1461 | ||
1462 | if (msg->msg_namelen) { | |
1463 | err = unix_mkname(sunaddr, msg->msg_namelen, &hash); | |
1464 | if (err < 0) | |
1465 | goto out; | |
1466 | namelen = err; | |
1467 | } else { | |
1468 | sunaddr = NULL; | |
1469 | err = -ENOTCONN; | |
1470 | other = unix_peer_get(sk); | |
1471 | if (!other) | |
1472 | goto out; | |
1473 | } | |
1474 | ||
f64f9e71 JP |
1475 | if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr |
1476 | && (err = unix_autobind(sock)) != 0) | |
1da177e4 LT |
1477 | goto out; |
1478 | ||
1479 | err = -EMSGSIZE; | |
1480 | if (len > sk->sk_sndbuf - 32) | |
1481 | goto out; | |
1482 | ||
1483 | skb = sock_alloc_send_skb(sk, len, msg->msg_flags&MSG_DONTWAIT, &err); | |
e27dfcea | 1484 | if (skb == NULL) |
1da177e4 LT |
1485 | goto out; |
1486 | ||
f78a5fda | 1487 | err = unix_scm_to_skb(siocb->scm, skb, true); |
25888e30 | 1488 | if (err < 0) |
7361c36c | 1489 | goto out_free; |
25888e30 | 1490 | max_level = err + 1; |
dc49c1f9 | 1491 | unix_get_secdata(siocb->scm, skb); |
877ce7c1 | 1492 | |
badff6d0 | 1493 | skb_reset_transport_header(skb); |
6eba6a37 | 1494 | err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); |
1da177e4 LT |
1495 | if (err) |
1496 | goto out_free; | |
1497 | ||
1498 | timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); | |
1499 | ||
1500 | restart: | |
1501 | if (!other) { | |
1502 | err = -ECONNRESET; | |
1503 | if (sunaddr == NULL) | |
1504 | goto out_free; | |
1505 | ||
097e66c5 | 1506 | other = unix_find_other(net, sunaddr, namelen, sk->sk_type, |
1da177e4 | 1507 | hash, &err); |
e27dfcea | 1508 | if (other == NULL) |
1da177e4 LT |
1509 | goto out_free; |
1510 | } | |
1511 | ||
d6ae3bae AC |
1512 | if (sk_filter(other, skb) < 0) { |
1513 | /* Toss the packet but do not return any error to the sender */ | |
1514 | err = len; | |
1515 | goto out_free; | |
1516 | } | |
1517 | ||
1c92b4e5 | 1518 | unix_state_lock(other); |
1da177e4 LT |
1519 | err = -EPERM; |
1520 | if (!unix_may_send(sk, other)) | |
1521 | goto out_unlock; | |
1522 | ||
1523 | if (sock_flag(other, SOCK_DEAD)) { | |
1524 | /* | |
1525 | * Check with 1003.1g - what should | |
1526 | * datagram error | |
1527 | */ | |
1c92b4e5 | 1528 | unix_state_unlock(other); |
1da177e4 LT |
1529 | sock_put(other); |
1530 | ||
1531 | err = 0; | |
1c92b4e5 | 1532 | unix_state_lock(sk); |
1da177e4 | 1533 | if (unix_peer(sk) == other) { |
e27dfcea | 1534 | unix_peer(sk) = NULL; |
1c92b4e5 | 1535 | unix_state_unlock(sk); |
1da177e4 LT |
1536 | |
1537 | unix_dgram_disconnected(sk, other); | |
1538 | sock_put(other); | |
1539 | err = -ECONNREFUSED; | |
1540 | } else { | |
1c92b4e5 | 1541 | unix_state_unlock(sk); |
1da177e4 LT |
1542 | } |
1543 | ||
1544 | other = NULL; | |
1545 | if (err) | |
1546 | goto out_free; | |
1547 | goto restart; | |
1548 | } | |
1549 | ||
1550 | err = -EPIPE; | |
1551 | if (other->sk_shutdown & RCV_SHUTDOWN) | |
1552 | goto out_unlock; | |
1553 | ||
1554 | if (sk->sk_type != SOCK_SEQPACKET) { | |
1555 | err = security_unix_may_send(sk->sk_socket, other->sk_socket); | |
1556 | if (err) | |
1557 | goto out_unlock; | |
1558 | } | |
1559 | ||
3c73419c | 1560 | if (unix_peer(other) != sk && unix_recvq_full(other)) { |
1da177e4 LT |
1561 | if (!timeo) { |
1562 | err = -EAGAIN; | |
1563 | goto out_unlock; | |
1564 | } | |
1565 | ||
1566 | timeo = unix_wait_for_peer(other, timeo); | |
1567 | ||
1568 | err = sock_intr_errno(timeo); | |
1569 | if (signal_pending(current)) | |
1570 | goto out_free; | |
1571 | ||
1572 | goto restart; | |
1573 | } | |
1574 | ||
3f66116e AC |
1575 | if (sock_flag(other, SOCK_RCVTSTAMP)) |
1576 | __net_timestamp(skb); | |
16e57262 | 1577 | maybe_add_creds(skb, sock, other); |
1da177e4 | 1578 | skb_queue_tail(&other->sk_receive_queue, skb); |
25888e30 ED |
1579 | if (max_level > unix_sk(other)->recursion_level) |
1580 | unix_sk(other)->recursion_level = max_level; | |
1c92b4e5 | 1581 | unix_state_unlock(other); |
1da177e4 LT |
1582 | other->sk_data_ready(other, len); |
1583 | sock_put(other); | |
f78a5fda | 1584 | scm_destroy(siocb->scm); |
1da177e4 LT |
1585 | return len; |
1586 | ||
1587 | out_unlock: | |
1c92b4e5 | 1588 | unix_state_unlock(other); |
1da177e4 LT |
1589 | out_free: |
1590 | kfree_skb(skb); | |
1591 | out: | |
1592 | if (other) | |
1593 | sock_put(other); | |
f78a5fda | 1594 | scm_destroy(siocb->scm); |
1da177e4 LT |
1595 | return err; |
1596 | } | |
1597 | ||
ac7bfa62 | 1598 | |
1da177e4 LT |
1599 | static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, |
1600 | struct msghdr *msg, size_t len) | |
1601 | { | |
1602 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
1603 | struct sock *sk = sock->sk; | |
1604 | struct sock *other = NULL; | |
6eba6a37 | 1605 | int err, size; |
f78a5fda | 1606 | struct sk_buff *skb; |
e27dfcea | 1607 | int sent = 0; |
1da177e4 | 1608 | struct scm_cookie tmp_scm; |
8ba69ba6 | 1609 | bool fds_sent = false; |
25888e30 | 1610 | int max_level; |
1da177e4 LT |
1611 | |
1612 | if (NULL == siocb->scm) | |
1613 | siocb->scm = &tmp_scm; | |
5f23b734 | 1614 | wait_for_unix_gc(); |
1da177e4 LT |
1615 | err = scm_send(sock, msg, siocb->scm); |
1616 | if (err < 0) | |
1617 | return err; | |
1618 | ||
1619 | err = -EOPNOTSUPP; | |
1620 | if (msg->msg_flags&MSG_OOB) | |
1621 | goto out_err; | |
1622 | ||
1623 | if (msg->msg_namelen) { | |
1624 | err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP; | |
1625 | goto out_err; | |
1626 | } else { | |
1da177e4 | 1627 | err = -ENOTCONN; |
830a1e5c | 1628 | other = unix_peer(sk); |
1da177e4 LT |
1629 | if (!other) |
1630 | goto out_err; | |
1631 | } | |
1632 | ||
1633 | if (sk->sk_shutdown & SEND_SHUTDOWN) | |
1634 | goto pipe_err; | |
1635 | ||
6eba6a37 | 1636 | while (sent < len) { |
1da177e4 | 1637 | /* |
e9df7d7f BL |
1638 | * Optimisation for the fact that under 0.01% of X |
1639 | * messages typically need breaking up. | |
1da177e4 LT |
1640 | */ |
1641 | ||
e9df7d7f | 1642 | size = len-sent; |
1da177e4 LT |
1643 | |
1644 | /* Keep two messages in the pipe so it schedules better */ | |
e9df7d7f BL |
1645 | if (size > ((sk->sk_sndbuf >> 1) - 64)) |
1646 | size = (sk->sk_sndbuf >> 1) - 64; | |
1da177e4 LT |
1647 | |
1648 | if (size > SKB_MAX_ALLOC) | |
1649 | size = SKB_MAX_ALLOC; | |
ac7bfa62 | 1650 | |
1da177e4 LT |
1651 | /* |
1652 | * Grab a buffer | |
1653 | */ | |
ac7bfa62 | 1654 | |
6eba6a37 ED |
1655 | skb = sock_alloc_send_skb(sk, size, msg->msg_flags&MSG_DONTWAIT, |
1656 | &err); | |
1da177e4 | 1657 | |
e27dfcea | 1658 | if (skb == NULL) |
1da177e4 LT |
1659 | goto out_err; |
1660 | ||
1661 | /* | |
1662 | * If you pass two values to the sock_alloc_send_skb | |
1663 | * it tries to grab the large buffer with GFP_NOFS | |
1664 | * (which can fail easily), and if it fails grab the | |
1665 | * fallback size buffer which is under a page and will | |
1666 | * succeed. [Alan] | |
1667 | */ | |
1668 | size = min_t(int, size, skb_tailroom(skb)); | |
1669 | ||
7361c36c | 1670 | |
f78a5fda DM |
1671 | /* Only send the fds in the first buffer */ |
1672 | err = unix_scm_to_skb(siocb->scm, skb, !fds_sent); | |
25888e30 | 1673 | if (err < 0) { |
7361c36c | 1674 | kfree_skb(skb); |
f78a5fda | 1675 | goto out_err; |
6209344f | 1676 | } |
25888e30 | 1677 | max_level = err + 1; |
7361c36c | 1678 | fds_sent = true; |
1da177e4 | 1679 | |
6eba6a37 ED |
1680 | err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size); |
1681 | if (err) { | |
1da177e4 | 1682 | kfree_skb(skb); |
f78a5fda | 1683 | goto out_err; |
1da177e4 LT |
1684 | } |
1685 | ||
1c92b4e5 | 1686 | unix_state_lock(other); |
1da177e4 LT |
1687 | |
1688 | if (sock_flag(other, SOCK_DEAD) || | |
1689 | (other->sk_shutdown & RCV_SHUTDOWN)) | |
1690 | goto pipe_err_free; | |
1691 | ||
16e57262 | 1692 | maybe_add_creds(skb, sock, other); |
1da177e4 | 1693 | skb_queue_tail(&other->sk_receive_queue, skb); |
25888e30 ED |
1694 | if (max_level > unix_sk(other)->recursion_level) |
1695 | unix_sk(other)->recursion_level = max_level; | |
1c92b4e5 | 1696 | unix_state_unlock(other); |
1da177e4 | 1697 | other->sk_data_ready(other, size); |
e27dfcea | 1698 | sent += size; |
1da177e4 | 1699 | } |
1da177e4 | 1700 | |
f78a5fda | 1701 | scm_destroy(siocb->scm); |
1da177e4 LT |
1702 | siocb->scm = NULL; |
1703 | ||
1704 | return sent; | |
1705 | ||
1706 | pipe_err_free: | |
1c92b4e5 | 1707 | unix_state_unlock(other); |
1da177e4 LT |
1708 | kfree_skb(skb); |
1709 | pipe_err: | |
6eba6a37 ED |
1710 | if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL)) |
1711 | send_sig(SIGPIPE, current, 0); | |
1da177e4 LT |
1712 | err = -EPIPE; |
1713 | out_err: | |
f78a5fda | 1714 | scm_destroy(siocb->scm); |
1da177e4 LT |
1715 | siocb->scm = NULL; |
1716 | return sent ? : err; | |
1717 | } | |
1718 | ||
1719 | static int unix_seqpacket_sendmsg(struct kiocb *kiocb, struct socket *sock, | |
1720 | struct msghdr *msg, size_t len) | |
1721 | { | |
1722 | int err; | |
1723 | struct sock *sk = sock->sk; | |
ac7bfa62 | 1724 | |
1da177e4 LT |
1725 | err = sock_error(sk); |
1726 | if (err) | |
1727 | return err; | |
1728 | ||
1729 | if (sk->sk_state != TCP_ESTABLISHED) | |
1730 | return -ENOTCONN; | |
1731 | ||
1732 | if (msg->msg_namelen) | |
1733 | msg->msg_namelen = 0; | |
1734 | ||
1735 | return unix_dgram_sendmsg(kiocb, sock, msg, len); | |
1736 | } | |
ac7bfa62 | 1737 | |
a05d2ad1 EB |
1738 | static int unix_seqpacket_recvmsg(struct kiocb *iocb, struct socket *sock, |
1739 | struct msghdr *msg, size_t size, | |
1740 | int flags) | |
1741 | { | |
1742 | struct sock *sk = sock->sk; | |
1743 | ||
1744 | if (sk->sk_state != TCP_ESTABLISHED) | |
1745 | return -ENOTCONN; | |
1746 | ||
1747 | return unix_dgram_recvmsg(iocb, sock, msg, size, flags); | |
1748 | } | |
1749 | ||
1da177e4 LT |
1750 | static void unix_copy_addr(struct msghdr *msg, struct sock *sk) |
1751 | { | |
1752 | struct unix_sock *u = unix_sk(sk); | |
1753 | ||
1754 | msg->msg_namelen = 0; | |
1755 | if (u->addr) { | |
1756 | msg->msg_namelen = u->addr->len; | |
1757 | memcpy(msg->msg_name, u->addr->name, u->addr->len); | |
1758 | } | |
1759 | } | |
1760 | ||
1761 | static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock, | |
1762 | struct msghdr *msg, size_t size, | |
1763 | int flags) | |
1764 | { | |
1765 | struct sock_iocb *siocb = kiocb_to_siocb(iocb); | |
1766 | struct scm_cookie tmp_scm; | |
1767 | struct sock *sk = sock->sk; | |
1768 | struct unix_sock *u = unix_sk(sk); | |
1769 | int noblock = flags & MSG_DONTWAIT; | |
1770 | struct sk_buff *skb; | |
1771 | int err; | |
f55bb7f9 | 1772 | int peeked, skip; |
1da177e4 LT |
1773 | |
1774 | err = -EOPNOTSUPP; | |
1775 | if (flags&MSG_OOB) | |
1776 | goto out; | |
1777 | ||
1778 | msg->msg_namelen = 0; | |
1779 | ||
b3ca9b02 RW |
1780 | err = mutex_lock_interruptible(&u->readlock); |
1781 | if (err) { | |
1782 | err = sock_intr_errno(sock_rcvtimeo(sk, noblock)); | |
1783 | goto out; | |
1784 | } | |
1da177e4 | 1785 | |
f55bb7f9 PE |
1786 | skip = sk_peek_offset(sk, flags); |
1787 | ||
1788 | skb = __skb_recv_datagram(sk, flags, &peeked, &skip, &err); | |
0a112258 FZ |
1789 | if (!skb) { |
1790 | unix_state_lock(sk); | |
1791 | /* Signal EOF on disconnected non-blocking SEQPACKET socket. */ | |
1792 | if (sk->sk_type == SOCK_SEQPACKET && err == -EAGAIN && | |
1793 | (sk->sk_shutdown & RCV_SHUTDOWN)) | |
1794 | err = 0; | |
1795 | unix_state_unlock(sk); | |
1da177e4 | 1796 | goto out_unlock; |
0a112258 | 1797 | } |
1da177e4 | 1798 | |
67426b75 ED |
1799 | wake_up_interruptible_sync_poll(&u->peer_wait, |
1800 | POLLOUT | POLLWRNORM | POLLWRBAND); | |
1da177e4 LT |
1801 | |
1802 | if (msg->msg_name) | |
1803 | unix_copy_addr(msg, skb->sk); | |
1804 | ||
f55bb7f9 PE |
1805 | if (size > skb->len - skip) |
1806 | size = skb->len - skip; | |
1807 | else if (size < skb->len - skip) | |
1da177e4 LT |
1808 | msg->msg_flags |= MSG_TRUNC; |
1809 | ||
f55bb7f9 | 1810 | err = skb_copy_datagram_iovec(skb, skip, msg->msg_iov, size); |
1da177e4 LT |
1811 | if (err) |
1812 | goto out_free; | |
1813 | ||
3f66116e AC |
1814 | if (sock_flag(sk, SOCK_RCVTSTAMP)) |
1815 | __sock_recv_timestamp(msg, sk, skb); | |
1816 | ||
1da177e4 LT |
1817 | if (!siocb->scm) { |
1818 | siocb->scm = &tmp_scm; | |
1819 | memset(&tmp_scm, 0, sizeof(tmp_scm)); | |
1820 | } | |
f78a5fda | 1821 | scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); |
877ce7c1 | 1822 | unix_set_secdata(siocb->scm, skb); |
1da177e4 | 1823 | |
6eba6a37 | 1824 | if (!(flags & MSG_PEEK)) { |
1da177e4 LT |
1825 | if (UNIXCB(skb).fp) |
1826 | unix_detach_fds(siocb->scm, skb); | |
f55bb7f9 PE |
1827 | |
1828 | sk_peek_offset_bwd(sk, skb->len); | |
6eba6a37 | 1829 | } else { |
1da177e4 LT |
1830 | /* It is questionable: on PEEK we could: |
1831 | - do not return fds - good, but too simple 8) | |
1832 | - return fds, and do not return them on read (old strategy, | |
1833 | apparently wrong) | |
1834 | - clone fds (I chose it for now, it is the most universal | |
1835 | solution) | |
ac7bfa62 YH |
1836 | |
1837 | POSIX 1003.1g does not actually define this clearly | |
1838 | at all. POSIX 1003.1g doesn't define a lot of things | |
1839 | clearly however! | |
1840 | ||
1da177e4 | 1841 | */ |
f55bb7f9 PE |
1842 | |
1843 | sk_peek_offset_fwd(sk, size); | |
1844 | ||
1da177e4 LT |
1845 | if (UNIXCB(skb).fp) |
1846 | siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); | |
1847 | } | |
1848 | err = size; | |
1849 | ||
1850 | scm_recv(sock, msg, siocb->scm, flags); | |
1851 | ||
1852 | out_free: | |
6eba6a37 | 1853 | skb_free_datagram(sk, skb); |
1da177e4 | 1854 | out_unlock: |
57b47a53 | 1855 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1856 | out: |
1857 | return err; | |
1858 | } | |
1859 | ||
1860 | /* | |
1861 | * Sleep until data has arrive. But check for races.. | |
1862 | */ | |
ac7bfa62 | 1863 | |
6eba6a37 | 1864 | static long unix_stream_data_wait(struct sock *sk, long timeo) |
1da177e4 LT |
1865 | { |
1866 | DEFINE_WAIT(wait); | |
1867 | ||
1c92b4e5 | 1868 | unix_state_lock(sk); |
1da177e4 LT |
1869 | |
1870 | for (;;) { | |
aa395145 | 1871 | prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); |
1da177e4 | 1872 | |
b03efcfb | 1873 | if (!skb_queue_empty(&sk->sk_receive_queue) || |
1da177e4 LT |
1874 | sk->sk_err || |
1875 | (sk->sk_shutdown & RCV_SHUTDOWN) || | |
1876 | signal_pending(current) || | |
1877 | !timeo) | |
1878 | break; | |
1879 | ||
1880 | set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); | |
1c92b4e5 | 1881 | unix_state_unlock(sk); |
1da177e4 | 1882 | timeo = schedule_timeout(timeo); |
1c92b4e5 | 1883 | unix_state_lock(sk); |
1da177e4 LT |
1884 | clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); |
1885 | } | |
1886 | ||
aa395145 | 1887 | finish_wait(sk_sleep(sk), &wait); |
1c92b4e5 | 1888 | unix_state_unlock(sk); |
1da177e4 LT |
1889 | return timeo; |
1890 | } | |
1891 | ||
1892 | ||
1893 | ||
1894 | static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock, | |
1895 | struct msghdr *msg, size_t size, | |
1896 | int flags) | |
1897 | { | |
1898 | struct sock_iocb *siocb = kiocb_to_siocb(iocb); | |
1899 | struct scm_cookie tmp_scm; | |
1900 | struct sock *sk = sock->sk; | |
1901 | struct unix_sock *u = unix_sk(sk); | |
e27dfcea | 1902 | struct sockaddr_un *sunaddr = msg->msg_name; |
1da177e4 LT |
1903 | int copied = 0; |
1904 | int check_creds = 0; | |
1905 | int target; | |
1906 | int err = 0; | |
1907 | long timeo; | |
fc0d7536 | 1908 | int skip; |
1da177e4 LT |
1909 | |
1910 | err = -EINVAL; | |
1911 | if (sk->sk_state != TCP_ESTABLISHED) | |
1912 | goto out; | |
1913 | ||
1914 | err = -EOPNOTSUPP; | |
1915 | if (flags&MSG_OOB) | |
1916 | goto out; | |
1917 | ||
1918 | target = sock_rcvlowat(sk, flags&MSG_WAITALL, size); | |
1919 | timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT); | |
1920 | ||
1921 | msg->msg_namelen = 0; | |
1922 | ||
1923 | /* Lock the socket to prevent queue disordering | |
1924 | * while sleeps in memcpy_tomsg | |
1925 | */ | |
1926 | ||
1927 | if (!siocb->scm) { | |
1928 | siocb->scm = &tmp_scm; | |
1929 | memset(&tmp_scm, 0, sizeof(tmp_scm)); | |
1930 | } | |
1931 | ||
b3ca9b02 RW |
1932 | err = mutex_lock_interruptible(&u->readlock); |
1933 | if (err) { | |
1934 | err = sock_intr_errno(timeo); | |
1935 | goto out; | |
1936 | } | |
1da177e4 | 1937 | |
fc0d7536 PE |
1938 | skip = sk_peek_offset(sk, flags); |
1939 | ||
6eba6a37 | 1940 | do { |
1da177e4 LT |
1941 | int chunk; |
1942 | struct sk_buff *skb; | |
1943 | ||
3c0d2f37 | 1944 | unix_state_lock(sk); |
6f01fd6e | 1945 | skb = skb_peek(&sk->sk_receive_queue); |
fc0d7536 | 1946 | again: |
6eba6a37 | 1947 | if (skb == NULL) { |
25888e30 | 1948 | unix_sk(sk)->recursion_level = 0; |
1da177e4 | 1949 | if (copied >= target) |
3c0d2f37 | 1950 | goto unlock; |
1da177e4 LT |
1951 | |
1952 | /* | |
1953 | * POSIX 1003.1g mandates this order. | |
1954 | */ | |
ac7bfa62 | 1955 | |
6eba6a37 ED |
1956 | err = sock_error(sk); |
1957 | if (err) | |
3c0d2f37 | 1958 | goto unlock; |
1da177e4 | 1959 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
3c0d2f37 MS |
1960 | goto unlock; |
1961 | ||
1962 | unix_state_unlock(sk); | |
1da177e4 LT |
1963 | err = -EAGAIN; |
1964 | if (!timeo) | |
1965 | break; | |
57b47a53 | 1966 | mutex_unlock(&u->readlock); |
1da177e4 LT |
1967 | |
1968 | timeo = unix_stream_data_wait(sk, timeo); | |
1969 | ||
b3ca9b02 RW |
1970 | if (signal_pending(current) |
1971 | || mutex_lock_interruptible(&u->readlock)) { | |
1da177e4 LT |
1972 | err = sock_intr_errno(timeo); |
1973 | goto out; | |
1974 | } | |
b3ca9b02 | 1975 | |
1da177e4 | 1976 | continue; |
3c0d2f37 MS |
1977 | unlock: |
1978 | unix_state_unlock(sk); | |
1979 | break; | |
1da177e4 | 1980 | } |
fc0d7536 PE |
1981 | |
1982 | if (skip >= skb->len) { | |
1983 | skip -= skb->len; | |
1984 | skb = skb_peek_next(skb, &sk->sk_receive_queue); | |
1985 | goto again; | |
1986 | } | |
1987 | ||
3c0d2f37 | 1988 | unix_state_unlock(sk); |
1da177e4 LT |
1989 | |
1990 | if (check_creds) { | |
1991 | /* Never glue messages from different writers */ | |
7361c36c | 1992 | if ((UNIXCB(skb).pid != siocb->scm->pid) || |
6f01fd6e | 1993 | (UNIXCB(skb).cred != siocb->scm->cred)) |
1da177e4 | 1994 | break; |
1da177e4 LT |
1995 | } else { |
1996 | /* Copy credentials */ | |
f78a5fda | 1997 | scm_set_cred(siocb->scm, UNIXCB(skb).pid, UNIXCB(skb).cred); |
1da177e4 LT |
1998 | check_creds = 1; |
1999 | } | |
2000 | ||
2001 | /* Copy address just once */ | |
6eba6a37 | 2002 | if (sunaddr) { |
1da177e4 LT |
2003 | unix_copy_addr(msg, skb->sk); |
2004 | sunaddr = NULL; | |
2005 | } | |
2006 | ||
fc0d7536 PE |
2007 | chunk = min_t(unsigned int, skb->len - skip, size); |
2008 | if (memcpy_toiovec(msg->msg_iov, skb->data + skip, chunk)) { | |
1da177e4 LT |
2009 | if (copied == 0) |
2010 | copied = -EFAULT; | |
2011 | break; | |
2012 | } | |
2013 | copied += chunk; | |
2014 | size -= chunk; | |
2015 | ||
2016 | /* Mark read part of skb as used */ | |
6eba6a37 | 2017 | if (!(flags & MSG_PEEK)) { |
1da177e4 LT |
2018 | skb_pull(skb, chunk); |
2019 | ||
fc0d7536 PE |
2020 | sk_peek_offset_bwd(sk, chunk); |
2021 | ||
1da177e4 LT |
2022 | if (UNIXCB(skb).fp) |
2023 | unix_detach_fds(siocb->scm, skb); | |
2024 | ||
6f01fd6e | 2025 | if (skb->len) |
1da177e4 | 2026 | break; |
1da177e4 | 2027 | |
6f01fd6e | 2028 | skb_unlink(skb, &sk->sk_receive_queue); |
70d4bf6d | 2029 | consume_skb(skb); |
1da177e4 LT |
2030 | |
2031 | if (siocb->scm->fp) | |
2032 | break; | |
6eba6a37 | 2033 | } else { |
1da177e4 LT |
2034 | /* It is questionable, see note in unix_dgram_recvmsg. |
2035 | */ | |
2036 | if (UNIXCB(skb).fp) | |
2037 | siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); | |
2038 | ||
fc0d7536 PE |
2039 | sk_peek_offset_fwd(sk, chunk); |
2040 | ||
1da177e4 LT |
2041 | break; |
2042 | } | |
2043 | } while (size); | |
2044 | ||
57b47a53 | 2045 | mutex_unlock(&u->readlock); |
1da177e4 LT |
2046 | scm_recv(sock, msg, siocb->scm, flags); |
2047 | out: | |
2048 | return copied ? : err; | |
2049 | } | |
2050 | ||
2051 | static int unix_shutdown(struct socket *sock, int mode) | |
2052 | { | |
2053 | struct sock *sk = sock->sk; | |
2054 | struct sock *other; | |
2055 | ||
2056 | mode = (mode+1)&(RCV_SHUTDOWN|SEND_SHUTDOWN); | |
2057 | ||
7180a031 AC |
2058 | if (!mode) |
2059 | return 0; | |
2060 | ||
2061 | unix_state_lock(sk); | |
2062 | sk->sk_shutdown |= mode; | |
2063 | other = unix_peer(sk); | |
2064 | if (other) | |
2065 | sock_hold(other); | |
2066 | unix_state_unlock(sk); | |
2067 | sk->sk_state_change(sk); | |
2068 | ||
2069 | if (other && | |
2070 | (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET)) { | |
2071 | ||
2072 | int peer_mode = 0; | |
2073 | ||
2074 | if (mode&RCV_SHUTDOWN) | |
2075 | peer_mode |= SEND_SHUTDOWN; | |
2076 | if (mode&SEND_SHUTDOWN) | |
2077 | peer_mode |= RCV_SHUTDOWN; | |
2078 | unix_state_lock(other); | |
2079 | other->sk_shutdown |= peer_mode; | |
2080 | unix_state_unlock(other); | |
2081 | other->sk_state_change(other); | |
2082 | if (peer_mode == SHUTDOWN_MASK) | |
2083 | sk_wake_async(other, SOCK_WAKE_WAITD, POLL_HUP); | |
2084 | else if (peer_mode & RCV_SHUTDOWN) | |
2085 | sk_wake_async(other, SOCK_WAKE_WAITD, POLL_IN); | |
1da177e4 | 2086 | } |
7180a031 AC |
2087 | if (other) |
2088 | sock_put(other); | |
2089 | ||
1da177e4 LT |
2090 | return 0; |
2091 | } | |
2092 | ||
885ee74d PE |
2093 | long unix_inq_len(struct sock *sk) |
2094 | { | |
2095 | struct sk_buff *skb; | |
2096 | long amount = 0; | |
2097 | ||
2098 | if (sk->sk_state == TCP_LISTEN) | |
2099 | return -EINVAL; | |
2100 | ||
2101 | spin_lock(&sk->sk_receive_queue.lock); | |
2102 | if (sk->sk_type == SOCK_STREAM || | |
2103 | sk->sk_type == SOCK_SEQPACKET) { | |
2104 | skb_queue_walk(&sk->sk_receive_queue, skb) | |
2105 | amount += skb->len; | |
2106 | } else { | |
2107 | skb = skb_peek(&sk->sk_receive_queue); | |
2108 | if (skb) | |
2109 | amount = skb->len; | |
2110 | } | |
2111 | spin_unlock(&sk->sk_receive_queue.lock); | |
2112 | ||
2113 | return amount; | |
2114 | } | |
2115 | EXPORT_SYMBOL_GPL(unix_inq_len); | |
2116 | ||
2117 | long unix_outq_len(struct sock *sk) | |
2118 | { | |
2119 | return sk_wmem_alloc_get(sk); | |
2120 | } | |
2121 | EXPORT_SYMBOL_GPL(unix_outq_len); | |
2122 | ||
1da177e4 LT |
2123 | static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) |
2124 | { | |
2125 | struct sock *sk = sock->sk; | |
e27dfcea | 2126 | long amount = 0; |
1da177e4 LT |
2127 | int err; |
2128 | ||
6eba6a37 ED |
2129 | switch (cmd) { |
2130 | case SIOCOUTQ: | |
885ee74d | 2131 | amount = unix_outq_len(sk); |
6eba6a37 ED |
2132 | err = put_user(amount, (int __user *)arg); |
2133 | break; | |
2134 | case SIOCINQ: | |
885ee74d PE |
2135 | amount = unix_inq_len(sk); |
2136 | if (amount < 0) | |
2137 | err = amount; | |
2138 | else | |
1da177e4 | 2139 | err = put_user(amount, (int __user *)arg); |
885ee74d | 2140 | break; |
6eba6a37 ED |
2141 | default: |
2142 | err = -ENOIOCTLCMD; | |
2143 | break; | |
1da177e4 LT |
2144 | } |
2145 | return err; | |
2146 | } | |
2147 | ||
6eba6a37 | 2148 | static unsigned int unix_poll(struct file *file, struct socket *sock, poll_table *wait) |
1da177e4 LT |
2149 | { |
2150 | struct sock *sk = sock->sk; | |
2151 | unsigned int mask; | |
2152 | ||
aa395145 | 2153 | sock_poll_wait(file, sk_sleep(sk), wait); |
1da177e4 LT |
2154 | mask = 0; |
2155 | ||
2156 | /* exceptional events? */ | |
2157 | if (sk->sk_err) | |
2158 | mask |= POLLERR; | |
2159 | if (sk->sk_shutdown == SHUTDOWN_MASK) | |
2160 | mask |= POLLHUP; | |
f348d70a | 2161 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
db40980f | 2162 | mask |= POLLRDHUP | POLLIN | POLLRDNORM; |
1da177e4 LT |
2163 | |
2164 | /* readable? */ | |
db40980f | 2165 | if (!skb_queue_empty(&sk->sk_receive_queue)) |
1da177e4 LT |
2166 | mask |= POLLIN | POLLRDNORM; |
2167 | ||
2168 | /* Connection-based need to check for termination and startup */ | |
6eba6a37 ED |
2169 | if ((sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) && |
2170 | sk->sk_state == TCP_CLOSE) | |
1da177e4 LT |
2171 | mask |= POLLHUP; |
2172 | ||
2173 | /* | |
2174 | * we set writable also when the other side has shut down the | |
2175 | * connection. This prevents stuck sockets. | |
2176 | */ | |
2177 | if (unix_writable(sk)) | |
2178 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; | |
2179 | ||
2180 | return mask; | |
2181 | } | |
2182 | ||
ec0d215f RW |
2183 | static unsigned int unix_dgram_poll(struct file *file, struct socket *sock, |
2184 | poll_table *wait) | |
3c73419c | 2185 | { |
ec0d215f RW |
2186 | struct sock *sk = sock->sk, *other; |
2187 | unsigned int mask, writable; | |
3c73419c | 2188 | |
aa395145 | 2189 | sock_poll_wait(file, sk_sleep(sk), wait); |
3c73419c RW |
2190 | mask = 0; |
2191 | ||
2192 | /* exceptional events? */ | |
2193 | if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue)) | |
2194 | mask |= POLLERR; | |
2195 | if (sk->sk_shutdown & RCV_SHUTDOWN) | |
5456f09a | 2196 | mask |= POLLRDHUP | POLLIN | POLLRDNORM; |
3c73419c RW |
2197 | if (sk->sk_shutdown == SHUTDOWN_MASK) |
2198 | mask |= POLLHUP; | |
2199 | ||
2200 | /* readable? */ | |
5456f09a | 2201 | if (!skb_queue_empty(&sk->sk_receive_queue)) |
3c73419c RW |
2202 | mask |= POLLIN | POLLRDNORM; |
2203 | ||
2204 | /* Connection-based need to check for termination and startup */ | |
2205 | if (sk->sk_type == SOCK_SEQPACKET) { | |
2206 | if (sk->sk_state == TCP_CLOSE) | |
2207 | mask |= POLLHUP; | |
2208 | /* connection hasn't started yet? */ | |
2209 | if (sk->sk_state == TCP_SYN_SENT) | |
2210 | return mask; | |
2211 | } | |
2212 | ||
973a34aa ED |
2213 | /* No write status requested, avoid expensive OUT tests. */ |
2214 | if (wait && !(wait->key & (POLLWRBAND | POLLWRNORM | POLLOUT))) | |
2215 | return mask; | |
2216 | ||
ec0d215f | 2217 | writable = unix_writable(sk); |
5456f09a ED |
2218 | other = unix_peer_get(sk); |
2219 | if (other) { | |
2220 | if (unix_peer(other) != sk) { | |
2221 | sock_poll_wait(file, &unix_sk(other)->peer_wait, wait); | |
2222 | if (unix_recvq_full(other)) | |
2223 | writable = 0; | |
ec0d215f | 2224 | } |
5456f09a | 2225 | sock_put(other); |
ec0d215f RW |
2226 | } |
2227 | ||
2228 | if (writable) | |
3c73419c RW |
2229 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; |
2230 | else | |
2231 | set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); | |
2232 | ||
3c73419c RW |
2233 | return mask; |
2234 | } | |
1da177e4 LT |
2235 | |
2236 | #ifdef CONFIG_PROC_FS | |
a53eb3fe PE |
2237 | static struct sock *first_unix_socket(int *i) |
2238 | { | |
2239 | for (*i = 0; *i <= UNIX_HASH_SIZE; (*i)++) { | |
2240 | if (!hlist_empty(&unix_socket_table[*i])) | |
2241 | return __sk_head(&unix_socket_table[*i]); | |
2242 | } | |
2243 | return NULL; | |
2244 | } | |
2245 | ||
2246 | static struct sock *next_unix_socket(int *i, struct sock *s) | |
2247 | { | |
2248 | struct sock *next = sk_next(s); | |
2249 | /* More in this chain? */ | |
2250 | if (next) | |
2251 | return next; | |
2252 | /* Look for next non-empty chain. */ | |
2253 | for ((*i)++; *i <= UNIX_HASH_SIZE; (*i)++) { | |
2254 | if (!hlist_empty(&unix_socket_table[*i])) | |
2255 | return __sk_head(&unix_socket_table[*i]); | |
2256 | } | |
2257 | return NULL; | |
2258 | } | |
2259 | ||
097e66c5 | 2260 | struct unix_iter_state { |
e372c414 | 2261 | struct seq_net_private p; |
097e66c5 DL |
2262 | int i; |
2263 | }; | |
e27dfcea | 2264 | |
1218854a | 2265 | static struct sock *unix_seq_idx(struct seq_file *seq, loff_t pos) |
1da177e4 | 2266 | { |
1218854a | 2267 | struct unix_iter_state *iter = seq->private; |
1da177e4 LT |
2268 | loff_t off = 0; |
2269 | struct sock *s; | |
2270 | ||
097e66c5 | 2271 | for (s = first_unix_socket(&iter->i); s; s = next_unix_socket(&iter->i, s)) { |
1218854a | 2272 | if (sock_net(s) != seq_file_net(seq)) |
097e66c5 | 2273 | continue; |
ac7bfa62 | 2274 | if (off == pos) |
1da177e4 LT |
2275 | return s; |
2276 | ++off; | |
2277 | } | |
2278 | return NULL; | |
2279 | } | |
2280 | ||
1da177e4 | 2281 | static void *unix_seq_start(struct seq_file *seq, loff_t *pos) |
9a429c49 | 2282 | __acquires(unix_table_lock) |
1da177e4 | 2283 | { |
fbe9cc4a | 2284 | spin_lock(&unix_table_lock); |
b9f3124f | 2285 | return *pos ? unix_seq_idx(seq, *pos - 1) : SEQ_START_TOKEN; |
1da177e4 LT |
2286 | } |
2287 | ||
2288 | static void *unix_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2289 | { | |
097e66c5 DL |
2290 | struct unix_iter_state *iter = seq->private; |
2291 | struct sock *sk = v; | |
1da177e4 LT |
2292 | ++*pos; |
2293 | ||
b9f3124f | 2294 | if (v == SEQ_START_TOKEN) |
097e66c5 DL |
2295 | sk = first_unix_socket(&iter->i); |
2296 | else | |
2297 | sk = next_unix_socket(&iter->i, sk); | |
1218854a | 2298 | while (sk && (sock_net(sk) != seq_file_net(seq))) |
097e66c5 DL |
2299 | sk = next_unix_socket(&iter->i, sk); |
2300 | return sk; | |
1da177e4 LT |
2301 | } |
2302 | ||
2303 | static void unix_seq_stop(struct seq_file *seq, void *v) | |
9a429c49 | 2304 | __releases(unix_table_lock) |
1da177e4 | 2305 | { |
fbe9cc4a | 2306 | spin_unlock(&unix_table_lock); |
1da177e4 LT |
2307 | } |
2308 | ||
2309 | static int unix_seq_show(struct seq_file *seq, void *v) | |
2310 | { | |
ac7bfa62 | 2311 | |
b9f3124f | 2312 | if (v == SEQ_START_TOKEN) |
1da177e4 LT |
2313 | seq_puts(seq, "Num RefCount Protocol Flags Type St " |
2314 | "Inode Path\n"); | |
2315 | else { | |
2316 | struct sock *s = v; | |
2317 | struct unix_sock *u = unix_sk(s); | |
1c92b4e5 | 2318 | unix_state_lock(s); |
1da177e4 | 2319 | |
71338aa7 | 2320 | seq_printf(seq, "%pK: %08X %08X %08X %04X %02X %5lu", |
1da177e4 LT |
2321 | s, |
2322 | atomic_read(&s->sk_refcnt), | |
2323 | 0, | |
2324 | s->sk_state == TCP_LISTEN ? __SO_ACCEPTCON : 0, | |
2325 | s->sk_type, | |
2326 | s->sk_socket ? | |
2327 | (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTED : SS_UNCONNECTED) : | |
2328 | (s->sk_state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING), | |
2329 | sock_i_ino(s)); | |
2330 | ||
2331 | if (u->addr) { | |
2332 | int i, len; | |
2333 | seq_putc(seq, ' '); | |
2334 | ||
2335 | i = 0; | |
2336 | len = u->addr->len - sizeof(short); | |
2337 | if (!UNIX_ABSTRACT(s)) | |
2338 | len--; | |
2339 | else { | |
2340 | seq_putc(seq, '@'); | |
2341 | i++; | |
2342 | } | |
2343 | for ( ; i < len; i++) | |
2344 | seq_putc(seq, u->addr->name->sun_path[i]); | |
2345 | } | |
1c92b4e5 | 2346 | unix_state_unlock(s); |
1da177e4 LT |
2347 | seq_putc(seq, '\n'); |
2348 | } | |
2349 | ||
2350 | return 0; | |
2351 | } | |
2352 | ||
56b3d975 | 2353 | static const struct seq_operations unix_seq_ops = { |
1da177e4 LT |
2354 | .start = unix_seq_start, |
2355 | .next = unix_seq_next, | |
2356 | .stop = unix_seq_stop, | |
2357 | .show = unix_seq_show, | |
2358 | }; | |
2359 | ||
1da177e4 LT |
2360 | static int unix_seq_open(struct inode *inode, struct file *file) |
2361 | { | |
e372c414 DL |
2362 | return seq_open_net(inode, file, &unix_seq_ops, |
2363 | sizeof(struct unix_iter_state)); | |
1da177e4 LT |
2364 | } |
2365 | ||
da7071d7 | 2366 | static const struct file_operations unix_seq_fops = { |
1da177e4 LT |
2367 | .owner = THIS_MODULE, |
2368 | .open = unix_seq_open, | |
2369 | .read = seq_read, | |
2370 | .llseek = seq_lseek, | |
e372c414 | 2371 | .release = seq_release_net, |
1da177e4 LT |
2372 | }; |
2373 | ||
2374 | #endif | |
2375 | ||
ec1b4cf7 | 2376 | static const struct net_proto_family unix_family_ops = { |
1da177e4 LT |
2377 | .family = PF_UNIX, |
2378 | .create = unix_create, | |
2379 | .owner = THIS_MODULE, | |
2380 | }; | |
2381 | ||
097e66c5 | 2382 | |
2c8c1e72 | 2383 | static int __net_init unix_net_init(struct net *net) |
097e66c5 DL |
2384 | { |
2385 | int error = -ENOMEM; | |
2386 | ||
a0a53c8b | 2387 | net->unx.sysctl_max_dgram_qlen = 10; |
1597fbc0 PE |
2388 | if (unix_sysctl_register(net)) |
2389 | goto out; | |
d392e497 | 2390 | |
097e66c5 | 2391 | #ifdef CONFIG_PROC_FS |
1597fbc0 PE |
2392 | if (!proc_net_fops_create(net, "unix", 0, &unix_seq_fops)) { |
2393 | unix_sysctl_unregister(net); | |
097e66c5 | 2394 | goto out; |
1597fbc0 | 2395 | } |
097e66c5 DL |
2396 | #endif |
2397 | error = 0; | |
2398 | out: | |
48dcc33e | 2399 | return error; |
097e66c5 DL |
2400 | } |
2401 | ||
2c8c1e72 | 2402 | static void __net_exit unix_net_exit(struct net *net) |
097e66c5 | 2403 | { |
1597fbc0 | 2404 | unix_sysctl_unregister(net); |
097e66c5 DL |
2405 | proc_net_remove(net, "unix"); |
2406 | } | |
2407 | ||
2408 | static struct pernet_operations unix_net_ops = { | |
2409 | .init = unix_net_init, | |
2410 | .exit = unix_net_exit, | |
2411 | }; | |
2412 | ||
1da177e4 LT |
2413 | static int __init af_unix_init(void) |
2414 | { | |
2415 | int rc = -1; | |
2416 | struct sk_buff *dummy_skb; | |
2417 | ||
ef047f5e | 2418 | BUILD_BUG_ON(sizeof(struct unix_skb_parms) > sizeof(dummy_skb->cb)); |
1da177e4 LT |
2419 | |
2420 | rc = proto_register(&unix_proto, 1); | |
ac7bfa62 YH |
2421 | if (rc != 0) { |
2422 | printk(KERN_CRIT "%s: Cannot create unix_sock SLAB cache!\n", | |
0dc47877 | 2423 | __func__); |
1da177e4 LT |
2424 | goto out; |
2425 | } | |
2426 | ||
2427 | sock_register(&unix_family_ops); | |
097e66c5 | 2428 | register_pernet_subsys(&unix_net_ops); |
1da177e4 LT |
2429 | out: |
2430 | return rc; | |
2431 | } | |
2432 | ||
2433 | static void __exit af_unix_exit(void) | |
2434 | { | |
2435 | sock_unregister(PF_UNIX); | |
1da177e4 | 2436 | proto_unregister(&unix_proto); |
097e66c5 | 2437 | unregister_pernet_subsys(&unix_net_ops); |
1da177e4 LT |
2438 | } |
2439 | ||
3d366960 DW |
2440 | /* Earlier than device_initcall() so that other drivers invoking |
2441 | request_module() don't end up in a loop when modprobe tries | |
2442 | to use a UNIX socket. But later than subsys_initcall() because | |
2443 | we depend on stuff initialised there */ | |
2444 | fs_initcall(af_unix_init); | |
1da177e4 LT |
2445 | module_exit(af_unix_exit); |
2446 | ||
2447 | MODULE_LICENSE("GPL"); | |
2448 | MODULE_ALIAS_NETPROTO(PF_UNIX); |