Bug Summary

File:afs/afs_conn.c
Location:line 171, column 9
Description:Dereference of null pointer (loaded from variable 'lcv')

Annotated Source Code

1/*
2 * Copyright 2000, International Business Machines Corporation and others.
3 * All Rights Reserved.
4 *
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
8 */
9
10/*
11 * Implements:
12 */
13#include <afsconfig.h>
14#include "afs/param.h"
15
16
17#include "afs/stds.h"
18#include "afs/sysincludes.h" /* Standard vendor system headers */
19
20#if !defined(UKERNEL1)
21#if !defined(AFS_LINUX20_ENV)
22#include <net/if.h>
23#endif
24#include <netinet/in.h>
25
26#ifdef AFS_SGI62_ENV
27#include "h/hashing.h"
28#endif
29#if !defined(AFS_HPUX110_ENV) && !defined(AFS_LINUX20_ENV) && !defined(AFS_DARWIN_ENV)
30#include <netinet/in_var.h>
31#endif /* ! AFS_HPUX110_ENV */
32#endif /* !defined(UKERNEL) */
33
34#include "afsincludes.h" /* Afs-based standard headers */
35#include "afs/afs_stats.h" /* afs statistics */
36
37#if defined(AFS_SUN5_ENV)
38#include <inet/led.h>
39#include <inet/common.h>
40#include <netinet/ip6.h>
41#include <inet/ip.h>
42#endif
43
44/* Exported variables */
45afs_rwlock_t afs_xconn; /* allocation lock for new things */
46afs_rwlock_t afs_xinterface; /* for multiple client address */
47afs_int32 cryptall = 0; /* encrypt all communications */
48
49/* some connection macros */
50
51/* a constructor */
52#define new_conn_vector(xcv)do { xcv = (struct sa_conn_vector *) afs_osi_Alloc(sizeof(struct
sa_conn_vector)); if (xcv) { memset((char *)xcv, 0, sizeof(struct
sa_conn_vector)); } } while (0);
\
53do { \
54 xcv = (struct sa_conn_vector *) \
55 afs_osi_Alloc(sizeof(struct sa_conn_vector)); \
56 if (xcv) { \
57 memset((char *)xcv, 0, sizeof(struct sa_conn_vector)); \
58 } \
59} while (0);
60
61/* select a connection to return (if no connection has lower utilization
62 * than any other) */
63#define conn_vec_select_conn(xcv, bix, conn)do { (bix) = ((xcv)->select_index)++ % 3; (conn) = &((
xcv)->cvec[bix]); } while (0);
\
64do { \
65 (bix) = ((xcv)->select_index)++ % CVEC_LEN3; \
66 (conn) = &((xcv)->cvec[bix]); \
67} while (0);
68
69#define struct_conn(s)((struct afs_conn *)(s)) ((struct afs_conn *)(s))
70
71#define REPORT_CONNECTIONS_ISSUED0 0 /* enable to see utilization */
72
73/**
74 * Find a connection with call slots available, allocating one
75 * if nothing is available and we find an allocated slot
76 * @param xcv A connection vector
77 * @param create If set, a new connection may be created
78 */
79static struct afs_conn *
80find_preferred_connection(struct sa_conn_vector *xcv, int create)
81{
82 afs_int32 cix, bix;
83 struct afs_conn *tc = NULL((void *)0);
84
85 bix = -1;
86 for(cix = 0; cix < CVEC_LEN3; ++cix) {
87 tc = &(xcv->cvec[cix]);
88 if (!tc->id) {
89 if (create) {
90 tc->parent = xcv;
91 tc->forceConnectFS = 1;
92 tc->activated = 1;
93 bix = cix;
94 break;
95 } /* create */
96 } else {
97 if (tc->refCount < (RX_MAXCALLS4-1)) {
98 bix = cix;
99 goto f_conn;
100 } else if (cix == (CVEC_LEN3-1))
101 conn_vec_select_conn(xcv, bix, tc)do { (bix) = ((xcv)->select_index)++ % 3; (tc) = &((xcv
)->cvec[bix]); } while (0);
;
102 } /* tc->id */
103 } /* for cix < CVEC_LEN */
104
105 if (bix < 0) {
106 afs_warn("find_preferred_connection: no connection and !create\n");
107 tc = NULL((void *)0);
108 goto out;
109 }
110
111f_conn:
112 tc->refCount++;
113 xcv->refCount++;
114
115#if REPORT_CONNECTIONS_ISSUED0
116 afs_warn("Issuing conn %d refCount=%d parent refCount=%d\n", bix,
117 tc->refCount, xcv->refCount);
118#endif
119
120out:
121 return (tc);
122
123} /* find_preferred_connection */
124
125
126/**
127 * Release all connections for unix user xu at server xs
128 * @param xu
129 * @param xs
130 */
131static void
132release_conns_user_server(struct unixuser *xu, struct server *xs)
133{
134 int cix, glocked;
135 struct srvAddr *sa;
136 struct afs_conn *tc;
137 struct sa_conn_vector *tcv, **lcv;
138 for (sa = (xs)->addr; sa; sa = sa->next_sa) {
139 lcv = &sa->conns;
140 for (tcv = *lcv; tcv; lcv = &tcv->next, tcv = *lcv) {
141 if (tcv->user == (xu) && tcv->refCount == 0) {
142 *lcv = tcv->next;
143 /* our old friend, the GLOCK */
144 glocked = ISAFS_GLOCK()(pthread_self() == afs_global_owner);
145 if (glocked)
146 AFS_GUNLOCK()do { do { if (!(pthread_self() == afs_global_owner)) { osi_Panic
("afs global lock not held"); } } while(0); memset(&afs_global_owner
, 0, sizeof(pthread_t)); do{if (!(pthread_mutex_unlock(&afs_global_lock
) == 0)) AssertionFailed("/home/wollman/openafs/src/afs/afs_conn.c"
, 146);}while(0); } while(0)
;
147 for(cix = 0; cix < CVEC_LEN3; ++cix) {
148 tc = &(tcv->cvec[cix]);
149 if (tc->activated)
150 rx_DestroyConnection(tc->id);
151 }
152 if (glocked)
153 AFS_GLOCK()do { do{if (!(pthread_mutex_lock(&afs_global_lock) == 0))
AssertionFailed("/home/wollman/openafs/src/afs/afs_conn.c", 153
);}while(0); afs_global_owner = pthread_self(); } while(0)
;
154 afs_osi_Free(tcv, sizeof(struct sa_conn_vector));
155 break; /* at most one instance per server */
156 } /*Found unreferenced connection for user */
157 }
158 } /*For each connection on the server */
159
160} /* release_conns_user_server */
161
162
163static void
164release_conns_vector(struct sa_conn_vector *xcv)
165{
166 int cix, glocked;
167 struct afs_conn *tc;
168 struct sa_conn_vector *tcv = NULL((void *)0);
169 struct sa_conn_vector **lcv = NULL((void *)0);
1
Variable 'lcv' initialized to a null pointer value
170 for (tcv = xcv; tcv; lcv = &tcv->next, tcv = *lcv) {
2
Loop condition is true. Entering loop body
171 *lcv = tcv->next;
3
Dereference of null pointer (loaded from variable 'lcv')
172 /* you know it, you love it, the GLOCK */
173 glocked = ISAFS_GLOCK()(pthread_self() == afs_global_owner);
174 if (glocked)
175 AFS_GUNLOCK()do { do { if (!(pthread_self() == afs_global_owner)) { osi_Panic
("afs global lock not held"); } } while(0); memset(&afs_global_owner
, 0, sizeof(pthread_t)); do{if (!(pthread_mutex_unlock(&afs_global_lock
) == 0)) AssertionFailed("/home/wollman/openafs/src/afs/afs_conn.c"
, 175);}while(0); } while(0)
; \
176 for(cix = 0; cix < CVEC_LEN3; ++cix) {
177 tc = &(tcv->cvec[cix]);
178 if (tc->activated)
179 rx_DestroyConnection( tc->id );
180 }
181 if (glocked)
182 AFS_GLOCK()do { do{if (!(pthread_mutex_lock(&afs_global_lock) == 0))
AssertionFailed("/home/wollman/openafs/src/afs/afs_conn.c", 182
);}while(0); afs_global_owner = pthread_self(); } while(0)
;
183 afs_osi_Free(tcv, sizeof(struct sa_conn_vector));
184 }
185
186} /* release_conns_vector */
187
188
189unsigned int VNOSERVERS = 0;
190
191/**
192 * Pick a security object to use for a connection to a given server,
193 * by a given user
194 *
195 * @param[in] conn
196 * The AFS connection for which the security object is required
197 * @param[out] secLevel
198 * The security level of the returned object
199 *
200 * @return
201 * An rx security object. This function is guaranteed to return
202 * an object, although that object may be rxnull (with a secLevel
203 * of 0)
204 */
205static struct rx_securityClass *
206afs_pickSecurityObject(struct afs_conn *conn, int *secLevel)
207{
208 struct rx_securityClass *secObj = NULL((void *)0);
209 union tokenUnion *token;
210
211 /* Do we have tokens ? */
212 if (conn->parent->user->states & UHasTokens1) {
213 token = afs_FindToken(conn->parent->user->tokens, RX_SECIDX_KAD);
214 if (token) {
215 *secLevel = RX_SECIDX_KAD;
216 /* kerberos tickets on channel 2 */
217 secObj = rxkad_NewClientSecurityObject(
218 cryptall ? rxkad_crypt2 : rxkad_clear0,
219 (struct ktc_encryptionKey *)
220 token->rxkad.clearToken.HandShakeKey,
221 token->rxkad.clearToken.AuthHandle,
222 token->rxkad.ticketLen, token->rxkad.ticket);
223 /* We're going to use this token, so populate the viced */
224 conn->parent->user->viceId = token->rxkad.clearToken.ViceId;
225 }
226 }
227 if (secObj == NULL((void *)0)) {
228 *secLevel = 0;
229 secObj = rxnull_NewClientSecurityObject();
230 }
231
232 return secObj;
233}
234
235
236/**
237 * Try setting up a connection to the server containing the specified fid.
238 * Gets the volume, checks if it's up and does the connection by server address.
239 *
240 * @param afid
241 * @param areq Request filled in by the caller.
242 * @param locktype Type of lock that will be used.
243 *
244 * @return The conn struct, or NULL.
245 */
246struct afs_conn *
247afs_Conn(struct VenusFid *afid, struct vrequest *areq,
248 afs_int32 locktype, struct rx_connection **rxconn)
249{
250 u_short fsport = AFS_FSPORT((unsigned short) (__builtin_constant_p(7000) ? (__uint16_t)(
((__uint16_t)(7000)) << 8 | ((__uint16_t)(7000)) >>
8) : __bswap16_var(7000)))
;
251 struct volume *tv;
252 struct afs_conn *tconn = NULL((void *)0);
253 struct srvAddr *lowp = NULL((void *)0);
254 struct unixuser *tu;
255 int notbusy;
256 int i;
257 struct srvAddr *sa1p;
258
259 *rxconn = NULL((void *)0);
260
261 AFS_STATCNT(afs_Conn)((afs_cmstats.callInfo.C_afs_Conn)++);
262 /* Get fid's volume. */
263 tv = afs_GetVolume(afid, areq, READ_LOCK1);
264 if (!tv) {
265 if (areq) {
266 afs_FinalizeReq(areq);
267 areq->volumeError = 1;
268 }
269 return NULL((void *)0);
270 }
271
272 if (tv->serverHost[0] && tv->serverHost[0]->cell) {
273 fsport = tv->serverHost[0]->cell->fsport;
274 } else {
275 VNOSERVERS++;
276 }
277
278 /* First is always lowest rank, if it's up */
279 if ((tv->status[0] == not_busy) && tv->serverHost[0]
280 && !(tv->serverHost[0]->addr->sa_flags & SRVR_ISDOWN0x20) &&
281 !(((areq->idleError > 0) || (areq->tokenError > 0))
282 && (areq->skipserver[0] == 1)))
283 lowp = tv->serverHost[0]->addr;
284
285 /* Otherwise we look at all of them. There are seven levels of
286 * not_busy. This means we will check a volume seven times before it
287 * is marked offline. Ideally, we only need two levels, but this
288 * serves a second purpose of waiting some number of seconds before
289 * the client decides the volume is offline (ie: a clone could finish
290 * in this time).
291 */
292 for (notbusy = not_busy; (!lowp && (notbusy <= end_not_busy)); notbusy++) {
293 for (i = 0; i < AFS_MAXHOSTS13 && tv->serverHost[i]; i++) {
294 if (((areq->tokenError > 0)||(areq->idleError > 0))
295 && (areq->skipserver[i] == 1))
296 continue;
297 if (tv->status[i] != notbusy) {
298 if (tv->status[i] == rd_busy || tv->status[i] == rdwr_busy) {
299 if (!areq->busyCount)
300 areq->busyCount++;
301 } else if (tv->status[i] == offline) {
302 if (!areq->volumeError)
303 areq->volumeError = VOLMISSING1;
304 }
305 continue;
306 }
307 for (sa1p = tv->serverHost[i]->addr; sa1p; sa1p = sa1p->next_sa) {
308 if (sa1p->sa_flags & SRVR_ISDOWN0x20)
309 continue;
310 if (!lowp || (lowp->sa_iprank > sa1p->sa_iprank))
311 lowp = sa1p;
312 }
313 }
314 }
315 afs_PutVolume(tv, READ_LOCK)((tv)->refCount--);
316
317 if (lowp) {
318 tu = afs_GetUser(areq->uid, afid->Cell, SHARED_LOCK4);
319 tconn = afs_ConnBySA(lowp, fsport, afid->Cell, tu, 0 /*!force */ ,
320 1 /*create */ , locktype, rxconn);
321
322 afs_PutUser(tu, SHARED_LOCK4);
323 }
324
325 return tconn;
326} /*afs_Conn */
327
328
329/**
330 * Connects to a server by it's server address.
331 *
332 * @param sap Server address.
333 * @param aport Server port.
334 * @param acell
335 * @param tu Connect as this user.
336 * @param force_if_down
337 * @param create
338 * @param locktype Specifies type of lock to be used for this function.
339 *
340 * @return The new connection.
341 */
342struct afs_conn *
343afs_ConnBySA(struct srvAddr *sap, unsigned short aport, afs_int32 acell,
344 struct unixuser *tu, int force_if_down, afs_int32 create,
345 afs_int32 locktype, struct rx_connection **rxconn)
346{
347 int glocked, foundvec;
348 struct afs_conn *tc = NULL((void *)0);
349 struct sa_conn_vector *tcv = NULL((void *)0);
350 struct rx_securityClass *csec; /*Security class object */
351 int isec; /*Security index */
352 int service;
353
354 *rxconn = NULL((void *)0);
355
356 /* find cached connection */
357 ObtainSharedLock(&afs_xconn, 15)do { ; if (!(&afs_xconn)->excl_locked) (&afs_xconn
) -> excl_locked = 4; else Afs_Lock_Obtain(&afs_xconn,
4); (&afs_xconn)->pid_writer = (get_user_struct()->
u_procp->p_pid ); (&afs_xconn)->src_indicator = 15;
} while (0)
;
358 foundvec = 0;
359 for (tcv = sap->conns; tcv; tcv = tcv->next) {
360 if (tcv->user == tu && tcv->port == aport) {
361 /* return most eligible conn */
362 if (!foundvec)
363 foundvec = 1;
364 UpgradeSToWLock(&afs_xconn, 37)do { ; if (!(&afs_xconn)->readers_reading) (&afs_xconn
)->excl_locked = 2; else Afs_Lock_Obtain(&afs_xconn, 6
); (&afs_xconn)->pid_writer = (get_user_struct()->u_procp
->p_pid ); (&afs_xconn)->src_indicator = 37; } while
(0)
;
365 tc = find_preferred_connection(tcv, create);
366 ConvertWToSLock(&afs_xconn)do { ; (&afs_xconn)->excl_locked = 4; if((&afs_xconn
)->wait_states) Afs_Lock_ReleaseR(&afs_xconn); } while
(0)
;
367 break;
368 }
369 }
370
371 if (!tc && !create) {
372 /* Not found and can't create a new one. */
373 ReleaseSharedLock(&afs_xconn)do { ; (&afs_xconn)->excl_locked &= ~(4 | 2); if (
(&afs_xconn)->wait_states) Afs_Lock_ReleaseR(&afs_xconn
); (&afs_xconn)->pid_writer=0; } while (0)
;
374 return NULL((void *)0);
375 }
376
377 if (AFS_IS_DISCONNECTED(afs_is_disconnected) && !AFS_IN_SYNC(afs_in_sync)) {
378 afs_warnuser("afs_ConnBySA: disconnected\n");
379 ReleaseSharedLock(&afs_xconn)do { ; (&afs_xconn)->excl_locked &= ~(4 | 2); if (
(&afs_xconn)->wait_states) Afs_Lock_ReleaseR(&afs_xconn
); (&afs_xconn)->pid_writer=0; } while (0)
;
380 return NULL((void *)0);
381 }
382
383 if (!foundvec && create) {
384 /* No such connection vector exists. Create one and splice it in.
385 * Make sure the server record has been marked as used (for the purposes
386 * of calculating up & down times, it's now considered to be an
387 * ``active'' server). Also make sure the server's lastUpdateEvalTime
388 * gets set, marking the time of its ``birth''.
389 */
390 UpgradeSToWLock(&afs_xconn, 37)do { ; if (!(&afs_xconn)->readers_reading) (&afs_xconn
)->excl_locked = 2; else Afs_Lock_Obtain(&afs_xconn, 6
); (&afs_xconn)->pid_writer = (get_user_struct()->u_procp
->p_pid ); (&afs_xconn)->src_indicator = 37; } while
(0)
;
391 new_conn_vector(tcv)do { tcv = (struct sa_conn_vector *) afs_osi_Alloc(sizeof(struct
sa_conn_vector)); if (tcv) { memset((char *)tcv, 0, sizeof(struct
sa_conn_vector)); } } while (0);
;
392
393 tcv->user = tu;
394 tcv->port = aport;
395 tcv->srvr = sap;
396 tcv->next = sap->conns;
397 sap->conns = tcv;
398
399 /* all struct afs_conn ptrs come from here */
400 tc = find_preferred_connection(tcv, create);
401
402 afs_ActivateServer(sap);
403
404 ConvertWToSLock(&afs_xconn)do { ; (&afs_xconn)->excl_locked = 4; if((&afs_xconn
)->wait_states) Afs_Lock_ReleaseR(&afs_xconn); } while
(0)
;
405 } /* end of if (!tcv) */
406
407 if (!tc) {
408 /* Not found and no alternatives. */
409 ReleaseSharedLock(&afs_xconn)do { ; (&afs_xconn)->excl_locked &= ~(4 | 2); if (
(&afs_xconn)->wait_states) Afs_Lock_ReleaseR(&afs_xconn
); (&afs_xconn)->pid_writer=0; } while (0)
;
410 return NULL((void *)0);
411 }
412
413 if (tu->states & UTokensBad2) {
414 /* we may still have an authenticated RPC connection here,
415 * we'll have to create a new, unauthenticated, connection.
416 * Perhaps a better way to do this would be to set
417 * conn->forceConnectFS on all conns when the token first goes
418 * bad, but that's somewhat trickier, due to locking
419 * constraints (though not impossible).
420 */
421 if (tc->id && (rx_SecurityClassOf(tc->id)((tc->id)->securityIndex) != 0)) {
422 tc->forceConnectFS = 1; /* force recreation of connection */
423 }
424 tu->states &= ~UHasTokens1; /* remove the authentication info */
425 }
426
427 glocked = ISAFS_GLOCK()(pthread_self() == afs_global_owner);
428 if (tc->forceConnectFS) {
429 UpgradeSToWLock(&afs_xconn, 38)do { ; if (!(&afs_xconn)->readers_reading) (&afs_xconn
)->excl_locked = 2; else Afs_Lock_Obtain(&afs_xconn, 6
); (&afs_xconn)->pid_writer = (get_user_struct()->u_procp
->p_pid ); (&afs_xconn)->src_indicator = 38; } while
(0)
;
430 csec = (struct rx_securityClass *)0;
431 if (tc->id) {
432 if (glocked)
433 AFS_GUNLOCK()do { do { if (!(pthread_self() == afs_global_owner)) { osi_Panic
("afs global lock not held"); } } while(0); memset(&afs_global_owner
, 0, sizeof(pthread_t)); do{if (!(pthread_mutex_unlock(&afs_global_lock
) == 0)) AssertionFailed("/home/wollman/openafs/src/afs/afs_conn.c"
, 433);}while(0); } while(0)
;
434 rx_DestroyConnection(tc->id);
435 if (glocked)
436 AFS_GLOCK()do { do{if (!(pthread_mutex_lock(&afs_global_lock) == 0))
AssertionFailed("/home/wollman/openafs/src/afs/afs_conn.c", 436
);}while(0); afs_global_owner = pthread_self(); } while(0)
;
437 }
438 /*
439 * Stupid hack to determine if using vldb service or file system
440 * service.
441 */
442 if (aport == sap->server->cell->vlport)
443 service = 52;
444 else
445 service = 1;
446 isec = 0;
447
448 csec = afs_pickSecurityObject(tc, &isec);
449
450 if (glocked)
451 AFS_GUNLOCK()do { do { if (!(pthread_self() == afs_global_owner)) { osi_Panic
("afs global lock not held"); } } while(0); memset(&afs_global_owner
, 0, sizeof(pthread_t)); do{if (!(pthread_mutex_unlock(&afs_global_lock
) == 0)) AssertionFailed("/home/wollman/openafs/src/afs/afs_conn.c"
, 451);}while(0); } while(0)
;
452 tc->id = rx_NewConnection(sap->sa_ip, aport, service, csec, isec);
453 if (glocked)
454 AFS_GLOCK()do { do{if (!(pthread_mutex_lock(&afs_global_lock) == 0))
AssertionFailed("/home/wollman/openafs/src/afs/afs_conn.c", 454
);}while(0); afs_global_owner = pthread_self(); } while(0)
;
455 if (service == 52) {
456 rx_SetConnHardDeadTime(tc->id, afs_rx_harddead);
457 }
458 /* set to a RX_CALL_TIMEOUT error to allow MTU retry to trigger */
459 rx_SetServerConnIdleDeadErr(tc->id, RX_CALL_DEAD)((tc->id)->idleDeadErr = ((-1)));
460 rx_SetConnIdleDeadTime(tc->id, afs_rx_idledead);
461 rx_SetMsgsizeRetryErr(tc->id, RX_MSGSIZE)((tc->id)->msgsizeRetryErr = ((-8)));
462
463 /*
464 * Only do this for the base connection, not per-user.
465 * Will need to be revisited if/when CB gets security.
466 */
467 if ((isec == 0) && (service != 52) && !(tu->states & UTokensBad2) &&
468 (tu->viceId == UNDEFVID(-1)))
469 rx_SetConnSecondsUntilNatPing(tc->id, 20);
470
471 tc->forceConnectFS = 0; /* apparently we're appropriately connected now */
472 if (csec)
473 rxs_Release(csec);
474 ConvertWToSLock(&afs_xconn)do { ; (&afs_xconn)->excl_locked = 4; if((&afs_xconn
)->wait_states) Afs_Lock_ReleaseR(&afs_xconn); } while
(0)
;
475 } /* end of if (tc->forceConnectFS)*/
476
477 *rxconn = tc->id;
478 rx_GetConnection(*rxconn);
479
480 ReleaseSharedLock(&afs_xconn)do { ; (&afs_xconn)->excl_locked &= ~(4 | 2); if (
(&afs_xconn)->wait_states) Afs_Lock_ReleaseR(&afs_xconn
); (&afs_xconn)->pid_writer=0; } while (0)
;
481 return tc;
482}
483
484/**
485 * forceConnectFS is set whenever we must recompute the connection. UTokensBad
486 * is true only if we know that the tokens are bad. We thus clear this flag
487 * when we get a new set of tokens..
488 * Having force... true and UTokensBad true simultaneously means that the tokens
489 * went bad and we're supposed to create a new, unauthenticated, connection.
490 *
491 * @param aserver Server to connect to.
492 * @param aport Connection port.
493 * @param acell The cell where all of this happens.
494 * @param areq The request.
495 * @param aforce Force connection?
496 * @param locktype Type of lock to be used.
497 *
498 * @return The established connection.
499 */
500struct afs_conn *
501afs_ConnByHost(struct server *aserver, unsigned short aport, afs_int32 acell,
502 struct vrequest *areq, int aforce, afs_int32 locktype,
503 struct rx_connection **rxconn)
504{
505 struct unixuser *tu;
506 struct afs_conn *tc = NULL((void *)0);
507 struct srvAddr *sa = NULL((void *)0);
508
509 *rxconn = NULL((void *)0);
510
511 AFS_STATCNT(afs_ConnByHost)((afs_cmstats.callInfo.C_afs_ConnByHost)++);
512
513 if (AFS_IS_DISCONNECTED(afs_is_disconnected) && !AFS_IN_SYNC(afs_in_sync)) {
514 afs_warnuser("afs_ConnByHost: disconnected\n");
515 return NULL((void *)0);
516 }
517
518/*
519 1. look for an existing connection
520 2. create a connection at an address believed to be up
521 (if aforce is true, create a connection at the first address)
522*/
523
524 tu = afs_GetUser(areq->uid, acell, SHARED_LOCK4);
525
526 for (sa = aserver->addr; sa; sa = sa->next_sa) {
527 tc = afs_ConnBySA(sa, aport, acell, tu, aforce,
528 0 /*don't create one */ ,
529 locktype, rxconn);
530 if (tc)
531 break;
532 }
533
534 if (!tc) {
535 for (sa = aserver->addr; sa; sa = sa->next_sa) {
536 tc = afs_ConnBySA(sa, aport, acell, tu, aforce,
537 1 /*create one */ ,
538 locktype, rxconn);
539 if (tc)
540 break;
541 }
542 }
543
544 afs_PutUser(tu, SHARED_LOCK4);
545 return tc;
546
547} /*afs_ConnByHost */
548
549
550/**
551 * Connect by multiple hosts.
552 * Try to connect to one of the hosts from the ahosts array.
553 *
554 * @param ahosts Multiple hosts to connect to.
555 * @param aport Connection port.
556 * @param acell The cell where all of this happens.
557 * @param areq The request.
558 * @param locktype Type of lock to be used.
559 *
560 * @return The established connection or NULL.
561 */
562struct afs_conn *
563afs_ConnByMHosts(struct server *ahosts[], unsigned short aport,
564 afs_int32 acell, struct vrequest *areq,
565 afs_int32 locktype, struct rx_connection **rxconn)
566{
567 afs_int32 i;
568 struct afs_conn *tconn;
569 struct server *ts;
570
571 *rxconn = NULL((void *)0);
572
573 /* try to find any connection from the set */
574 AFS_STATCNT(afs_ConnByMHosts)((afs_cmstats.callInfo.C_afs_ConnByMHosts)++);
575 for (i = 0; i < AFS_MAXCELLHOSTS8; i++) {
576 if ((ts = ahosts[i]) == NULL((void *)0))
577 break;
578 tconn = afs_ConnByHost(ts, aport, acell, areq, 0, locktype, rxconn);
579 if (tconn) {
580 return tconn;
581 }
582 }
583 return NULL((void *)0);
584
585} /*afs_ConnByMHosts */
586
587
588/**
589 * Decrement reference count to this connection.
590 * @param ac
591 * @param locktype
592 */
593void
594afs_PutConn(struct afs_conn *ac, struct rx_connection *rxconn,
595 afs_int32 locktype)
596{
597 AFS_STATCNT(afs_PutConn)((afs_cmstats.callInfo.C_afs_PutConn)++);
598 ac->refCount--;
599 if (ac->refCount < 0) {
600 static int warned = 0;
601 /* So, someone is 'put'ing more refs than they got. From now on, we
602 * have no idea if the structure is actually still in use, so just
603 * set the refcount to a really negative number to make it unlikely
604 * that the count will ever reach 0 and the conn gets freed. This
605 * leaks memory, but the alternative is panicing, or risking memory
606 * corruption. */
607 ac->refCount = -10000;
608 if (!warned) {
609 warned = 1;
610 afs_warn("afs_PutConn: negative refCount with 0x%lx; this should "
611 "not ever happen! Trying to carry on anyway, but please "
612 "report this issue\n",
613 (unsigned long)(uintptrszunsigned int)ac);
614 }
615 return;
616 }
617 ac->parent->refCount--;
618 rx_PutConnection(rxconn)rx_DestroyConnection(rxconn);
619} /*afs_PutConn */
620
621
622/**
623 * Free up a connection vector, allowing, eg, code in afs_user.c
624 * to ignore how connections are stored/pooled
625 * @param tcv
626 */
627void
628afs_ReleaseConns(struct sa_conn_vector *tcv) {
629 release_conns_vector(tcv);
630}
631
632
633/**
634 * Free connection vector(s) for a user
635 * @param au
636 */
637void
638afs_ReleaseConnsUser(struct unixuser *au) {
639
640 int i;
641 struct server *ts;
642
643 for (i = 0; i < NSERVERS16; i++) {
644 for (ts = afs_servers[i]; ts; ts = ts->next) {
645 release_conns_user_server(au, ts);
646 } /*For each server on chain */
647 } /*For each chain */
648}
649
650
651/**
652 * For multi homed clients, a RPC may timeout because of a
653 * client network interface going down. We need to reopen new
654 * connections in this case.
655 *
656 * @param sap Server address.
657 */
658void
659ForceNewConnections(struct srvAddr *sap)
660{
661 int cix;
662 struct afs_conn *tc = NULL((void *)0);
663 struct sa_conn_vector *tcv = NULL((void *)0);
664
665 if (!sap)
666 return; /* defensive check */
667
668 ObtainWriteLock(&afs_xconn, 413)do { ; if (!(&afs_xconn)->excl_locked && !(&
afs_xconn)->readers_reading) (&afs_xconn) -> excl_locked
= 2; else Afs_Lock_Obtain(&afs_xconn, 2); (&afs_xconn
)->pid_writer = (get_user_struct()->u_procp->p_pid )
; (&afs_xconn)->src_indicator = 413; } while (0)
;
669 for (tcv = sap->conns; tcv; tcv = tcv->next) {
670 for(cix = 0; cix < CVEC_LEN3; ++cix) {
671 tc = &(tcv->cvec[cix]);
672 if (tc->activated)
673 tc->forceConnectFS = 1;
674 }
675 }
676 ReleaseWriteLock(&afs_xconn)do { ; (&afs_xconn)->excl_locked &= ~2; if ((&
afs_xconn)->wait_states) Afs_Lock_ReleaseR(&afs_xconn)
; (&afs_xconn)->pid_writer=0; } while (0)
;
677}
678
679