source/smbd/blocking.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Blocking Locking functions
   4    Copyright (C) Jeremy Allison 1998-2003
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22
  23 /****************************************************************************
  24  This is the structure to queue to implement blocking locks.
  25  notify. It consists of the requesting SMB and the expiry time.
  26 *****************************************************************************/
  27
  28 typedef struct _blocking_lock_record {
  29         struct _blocking_lock_record *next;
  30         struct _blocking_lock_record *prev;
  31         int com_type;
  32         files_struct *fsp;
  33         time_t expire_time;
  34         int lock_num;
  35         SMB_BIG_UINT offset;
  36         SMB_BIG_UINT count;
  37         uint16 lock_pid;
  38         char *inbuf;
  39         int length;
  40 } blocking_lock_record;
  41
  42 static blocking_lock_record *blocking_lock_queue;
  43
  44 /****************************************************************************
  45  Destructor for the above structure.
  46 ****************************************************************************/
  47
  48 static void free_blocking_lock_record(blocking_lock_record *blr)
  49 {
  50         DLIST_REMOVE(blocking_lock_queue, blr);
  51         SAFE_FREE(blr->inbuf);
  52         SAFE_FREE(blr);
  53 }
  54
  55 /****************************************************************************
  56  Get the files_struct given a particular queued SMB.
  57 *****************************************************************************/
  58
  59 static files_struct *get_fsp_from_pkt(char *inbuf)
  60 {
  61         switch(CVAL(inbuf,smb_com)) {
  62                 case SMBlock:
  63                 case SMBlockread:
  64                         return file_fsp(inbuf,smb_vwv0);
  65                 case SMBlockingX:
  66                         return file_fsp(inbuf,smb_vwv2);
  67                 default:
  68                         DEBUG(0,("get_fsp_from_pkt: PANIC - unknown type on blocking lock queue - exiting.!\n"));
  69                         exit_server("PANIC - unknown type on blocking lock queue");
  70         }
  71         return NULL; /* Keep compiler happy. */
  72 }
  73
  74 /****************************************************************************
  75  Determine if this is a secondary element of a chained SMB.
  76   **************************************************************************/
  77
  78 static BOOL in_chained_smb(void)
  79 {
  80         return (chain_size != 0);
  81 }
  82
  83 static void received_unlock_msg(int msg_type, struct process_id src,
  84                                 void *buf, size_t len);
  85
  86 /****************************************************************************
  87  Function to push a blocking lock request onto the lock queue.
  88 ****************************************************************************/
  89
  90 BOOL push_blocking_lock_request( char *inbuf, int length, int lock_timeout,
  91                 int lock_num, uint16 lock_pid, SMB_BIG_UINT offset, SMB_BIG_UINT count)
  92 {
  93         static BOOL set_lock_msg;
  94         blocking_lock_record *blr, *tmp;
  95         BOOL my_lock_ctx = False;
  96         NTSTATUS status;
  97
  98         if(in_chained_smb() ) {
  99                 DEBUG(0,("push_blocking_lock_request: cannot queue a chained request (currently).\n"));
 100                 return False;
 101         }
 102
 103         /*
 104          * Now queue an entry on the blocking lock queue. We setup
 105          * the expiration time here.
 106          */
 107
 108         if((blr = SMB_MALLOC_P(blocking_lock_record)) == NULL) {
 109                 DEBUG(0,("push_blocking_lock_request: Malloc fail !\n" ));
 110                 return False;
 111         }
 112
 113         if((blr->inbuf = (char *)SMB_MALLOC(length)) == NULL) {
 114                 DEBUG(0,("push_blocking_lock_request: Malloc fail (2)!\n" ));
 115                 SAFE_FREE(blr);
 116                 return False;
 117         }
 118
 119         blr->com_type = CVAL(inbuf,smb_com);
 120         blr->fsp = get_fsp_from_pkt(inbuf);
 121         blr->expire_time = (lock_timeout == -1) ? (time_t)-1 : time(NULL) + (time_t)lock_timeout;
 122         blr->lock_num = lock_num;
 123         blr->lock_pid = lock_pid;
 124         blr->offset = offset;
 125         blr->count = count;
 126         memcpy(blr->inbuf, inbuf, length);
 127         blr->length = length;
 128
 129         /* Add a pending lock record for this. */
 130         status = brl_lock(blr->fsp->dev, blr->fsp->inode, blr->fsp->fnum,
 131                         lock_pid, procid_self(), blr->fsp->conn->cnum,
 132                         offset, count, PENDING_LOCK, &my_lock_ctx);
 133
 134         if (!NT_STATUS_IS_OK(status)) {
 135                 DEBUG(0,("push_blocking_lock_request: failed to add PENDING_LOCK record.\n"));
 136                 free_blocking_lock_record(blr);
 137                 return False;
 138         }
 139
 140         DLIST_ADD_END(blocking_lock_queue, blr, tmp);
 141
 142         /* Ensure we'll receive messages when this is unlocked. */
 143         if (!set_lock_msg) {
 144                 message_register(MSG_SMB_UNLOCK, received_unlock_msg);
 145                 set_lock_msg = True;
 146         }
 147
 148         DEBUG(3,("push_blocking_lock_request: lock request length=%d blocked with expiry time %d (+%d) \
 149 for fnum = %d, name = %s\n", length, (int)blr->expire_time, lock_timeout,
 150                 blr->fsp->fnum, blr->fsp->fsp_name ));
 151
 152         /* Push the MID of this packet on the signing queue. */
 153         srv_defer_sign_response(SVAL(inbuf,smb_mid));
 154
 155         return True;
 156 }
 157
 158 /****************************************************************************
 159  Return a smd with a given size.
 160 *****************************************************************************/
 161
 162 static void send_blocking_reply(char *outbuf, int outsize)
 163 {
 164         if(outsize > 4)
 165                 smb_setlen(outbuf,outsize - 4);
 166
 167         if (!send_smb(smbd_server_fd(),outbuf))
 168                 exit_server("send_blocking_reply: send_smb failed.");
 169 }
 170
 171 /****************************************************************************
 172  Return a lockingX success SMB.
 173 *****************************************************************************/
 174
 175 static void reply_lockingX_success(blocking_lock_record *blr)
 176 {
 177         char *outbuf = get_OutBuffer();
 178         int bufsize = BUFFER_SIZE;
 179         char *inbuf = blr->inbuf;
 180         int outsize = 0;
 181
 182         construct_reply_common(inbuf, outbuf);
 183         set_message(outbuf,2,0,True);
 184
 185         /*
 186          * As this message is a lockingX call we must handle
 187          * any following chained message correctly.
 188          * This is normally handled in construct_reply(),
 189          * but as that calls switch_message, we can't use
 190          * that here and must set up the chain info manually.
 191          */
 192
 193         outsize = chain_reply(inbuf,outbuf,blr->length,bufsize);
 194
 195         outsize += chain_size;
 196
 197         send_blocking_reply(outbuf,outsize);
 198 }
 199
 200 /****************************************************************************
 201  Return a generic lock fail error blocking call.
 202 *****************************************************************************/
 203
 204 static void generic_blocking_lock_error(blocking_lock_record *blr, NTSTATUS status)
 205 {
 206         char *outbuf = get_OutBuffer();
 207         char *inbuf = blr->inbuf;
 208         construct_reply_common(inbuf, outbuf);
 209
 210         /* whenever a timeout is given w2k maps LOCK_NOT_GRANTED to
 211            FILE_LOCK_CONFLICT! (tridge) */
 212         if (NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED)) {
 213                 status = NT_STATUS_FILE_LOCK_CONFLICT;
 214         }
 215
 216         ERROR_NT(status);
 217         if (!send_smb(smbd_server_fd(),outbuf))
 218                 exit_server("generic_blocking_lock_error: send_smb failed.");
 219 }
 220
 221 /****************************************************************************
 222  Return a lock fail error for a lockingX call. Undo all the locks we have
 223  obtained first.
 224 *****************************************************************************/
 225
 226 static void reply_lockingX_error(blocking_lock_record *blr, NTSTATUS status)
 227 {
 228         char *inbuf = blr->inbuf;
 229         files_struct *fsp = blr->fsp;
 230         connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
 231         uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
 232         SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT) 0;
 233         uint16 lock_pid;
 234         unsigned char locktype = CVAL(inbuf,smb_vwv3);
 235         BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 236         char *data;
 237         int i;
 238
 239         data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
 240
 241         /*
 242          * Data now points at the beginning of the list
 243          * of smb_lkrng structs.
 244          */
 245
 246         /*
 247          * Ensure we don't do a remove on the lock that just failed,
 248          * as under POSIX rules, if we have a lock already there, we
 249          * will delete it (and we shouldn't) .....
 250          */
 251
 252         for(i = blr->lock_num - 1; i >= 0; i--) {
 253                 BOOL err;
 254
 255                 lock_pid = get_lock_pid( data, i, large_file_format);
 256                 count = get_lock_count( data, i, large_file_format);
 257                 offset = get_lock_offset( data, i, large_file_format, &err);
 258
 259                 /*
 260                  * We know err cannot be set as if it was the lock
 261                  * request would never have been queued. JRA.
 262                  */
 263
 264                 do_unlock(fsp,conn,lock_pid,count,offset);
 265         }
 266
 267         generic_blocking_lock_error(blr, status);
 268 }
 269
 270 /****************************************************************************
 271  Return a lock fail error.
 272 *****************************************************************************/
 273
 274 static void blocking_lock_reply_error(blocking_lock_record *blr, NTSTATUS status)
 275 {
 276         switch(blr->com_type) {
 277         case SMBlock:
 278         case SMBlockread:
 279                 generic_blocking_lock_error(blr, status);
 280                 break;
 281         case SMBlockingX:
 282                 reply_lockingX_error(blr, status);
 283                 break;
 284         default:
 285                 DEBUG(0,("blocking_lock_reply_error: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 286                 exit_server("PANIC - unknown type on blocking lock queue");
 287         }
 288 }
 289
 290 /****************************************************************************
 291  Attempt to finish off getting all pending blocking locks for a lockread call.
 292  Returns True if we want to be removed from the list.
 293 *****************************************************************************/
 294
 295 static BOOL process_lockread(blocking_lock_record *blr)
 296 {
 297         char *outbuf = get_OutBuffer();
 298         char *inbuf = blr->inbuf;
 299         ssize_t nread = -1;
 300         char *data, *p;
 301         int outsize = 0;
 302         SMB_BIG_UINT startpos;
 303         size_t numtoread;
 304         NTSTATUS status;
 305         connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
 306         files_struct *fsp = blr->fsp;
 307         BOOL my_lock_ctx = False;
 308
 309         numtoread = SVAL(inbuf,smb_vwv1);
 310         startpos = (SMB_BIG_UINT)IVAL(inbuf,smb_vwv2);
 311
 312         numtoread = MIN(BUFFER_SIZE-outsize,numtoread);
 313         data = smb_buf(outbuf) + 3;
 314
 315         status = do_lock_spin( fsp, conn, SVAL(inbuf,smb_pid), (SMB_BIG_UINT)numtoread, startpos, READ_LOCK, &my_lock_ctx);
 316         if (NT_STATUS_V(status)) {
 317                 if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
 318                         !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
 319                         /*
 320                          * We have other than a "can't get lock"
 321                          * error. Send an error.
 322                          * Return True so we get dequeued.
 323                          */
 324                         generic_blocking_lock_error(blr, status);
 325                         return True;
 326                 }
 327
 328                 /*
 329                  * Still waiting for lock....
 330                  */
 331
 332                 DEBUG(10,("process_lockread: failed to get lock for file = %s. Still waiting....\n",
 333                           fsp->fsp_name));
 334                 return False;
 335         }
 336
 337         nread = read_file(fsp,data,startpos,numtoread);
 338
 339         if (nread < 0) {
 340                 generic_blocking_lock_error(blr,NT_STATUS_ACCESS_DENIED);
 341                 return True;
 342         }
 343
 344         construct_reply_common(inbuf, outbuf);
 345         outsize = set_message(outbuf,5,0,True);
 346
 347         outsize += nread;
 348         SSVAL(outbuf,smb_vwv0,nread);
 349         SSVAL(outbuf,smb_vwv5,nread+3);
 350         p = smb_buf(outbuf);
 351         *p++ = 1;
 352         SSVAL(p,0,nread); p += 2;
 353         set_message_end(outbuf, p+nread);
 354
 355         DEBUG(3, ( "process_lockread file = %s, fnum=%d num=%lu nread=%ld\n",
 356                    fsp->fsp_name, fsp->fnum, (unsigned long)numtoread, (long)nread ) );
 357
 358         send_blocking_reply(outbuf,outsize);
 359         return True;
 360 }
 361
 362 /****************************************************************************
 363  Attempt to finish off getting all pending blocking locks for a lock call.
 364  Returns True if we want to be removed from the list.
 365 *****************************************************************************/
 366
 367 static BOOL process_lock(blocking_lock_record *blr)
 368 {
 369         char *outbuf = get_OutBuffer();
 370         char *inbuf = blr->inbuf;
 371         int outsize;
 372         SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT)0;
 373         NTSTATUS status;
 374         connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
 375         files_struct *fsp = blr->fsp;
 376         BOOL my_lock_ctx = False;
 377
 378         count = IVAL_TO_SMB_OFF_T(inbuf,smb_vwv1);
 379         offset = IVAL_TO_SMB_OFF_T(inbuf,smb_vwv3);
 380
 381         errno = 0;
 382         status = do_lock_spin(fsp, conn, SVAL(inbuf,smb_pid), count, offset, WRITE_LOCK, &my_lock_ctx);
 383         if (NT_STATUS_IS_ERR(status)) {
 384                 if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
 385                         !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
 386                         /*
 387                          * We have other than a "can't get lock"
 388                          * error. Send an error.
 389                          * Return True so we get dequeued.
 390                          */
 391
 392                         blocking_lock_reply_error(blr, status);
 393                         return True;
 394                 }
 395                 /*
 396                  * Still can't get the lock - keep waiting.
 397                  */
 398                 DEBUG(10,("process_lock: failed to get lock for file = %s. Still waiting....\n",
 399                           fsp->fsp_name));
 400                 return False;
 401         }
 402
 403         /*
 404          * Success - we got the lock.
 405          */
 406
 407         DEBUG(3,("process_lock : file=%s fnum=%d offset=%.0f count=%.0f\n",
 408                  fsp->fsp_name, fsp->fnum, (double)offset, (double)count));
 409
 410         construct_reply_common(inbuf, outbuf);
 411         outsize = set_message(outbuf,0,0,True);
 412         send_blocking_reply(outbuf,outsize);
 413         return True;
 414 }
 415
 416 /****************************************************************************
 417  Attempt to finish off getting all pending blocking locks for a lockingX call.
 418  Returns True if we want to be removed from the list.
 419 *****************************************************************************/
 420
 421 static BOOL process_lockingX(blocking_lock_record *blr)
 422 {
 423         char *inbuf = blr->inbuf;
 424         unsigned char locktype = CVAL(inbuf,smb_vwv3);
 425         files_struct *fsp = blr->fsp;
 426         connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
 427         uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
 428         uint16 num_locks = SVAL(inbuf,smb_vwv7);
 429         SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT)0;
 430         uint16 lock_pid;
 431         BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 432         char *data;
 433         BOOL my_lock_ctx = False;
 434         NTSTATUS status = NT_STATUS_OK;
 435
 436         data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
 437
 438         /*
 439          * Data now points at the beginning of the list
 440          * of smb_lkrng structs.
 441          */
 442
 443         for(; blr->lock_num < num_locks; blr->lock_num++) {
 444                 BOOL err;
 445
 446                 lock_pid = get_lock_pid( data, blr->lock_num, large_file_format);
 447                 count = get_lock_count( data, blr->lock_num, large_file_format);
 448                 offset = get_lock_offset( data, blr->lock_num, large_file_format, &err);
 449
 450                 /*
 451                  * We know err cannot be set as if it was the lock
 452                  * request would never have been queued. JRA.
 453                  */
 454                 errno = 0;
 455                 status = do_lock_spin(fsp,conn,lock_pid,count,offset,
 456                                  ((locktype & 1) ? READ_LOCK : WRITE_LOCK), &my_lock_ctx);
 457                 if (NT_STATUS_IS_ERR(status)) break;
 458         }
 459
 460         if(blr->lock_num == num_locks) {
 461                 /*
 462                  * Success - we got all the locks.
 463                  */
 464
 465                 DEBUG(3,("process_lockingX file = %s, fnum=%d type=%d num_locks=%d\n",
 466                          fsp->fsp_name, fsp->fnum, (unsigned int)locktype, num_locks) );
 467
 468                 reply_lockingX_success(blr);
 469                 return True;
 470         } else if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
 471                         !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
 472                         /*
 473                          * We have other than a "can't get lock"
 474                          * error. Free any locks we had and return an error.
 475                          * Return True so we get dequeued.
 476                          */
 477
 478                 blocking_lock_reply_error(blr, status);
 479                 return True;
 480         }
 481
 482         /*
 483          * Still can't get all the locks - keep waiting.
 484          */
 485
 486         DEBUG(10,("process_lockingX: only got %d locks of %d needed for file %s, fnum = %d. \
 487 Waiting....\n",
 488                   blr->lock_num, num_locks, fsp->fsp_name, fsp->fnum));
 489
 490         return False;
 491 }
 492
 493 /****************************************************************************
 494  Process a blocking lock SMB.
 495  Returns True if we want to be removed from the list.
 496 *****************************************************************************/
 497
 498 static BOOL blocking_lock_record_process(blocking_lock_record *blr)
 499 {
 500         switch(blr->com_type) {
 501                 case SMBlock:
 502                         return process_lock(blr);
 503                 case SMBlockread:
 504                         return process_lockread(blr);
 505                 case SMBlockingX:
 506                         return process_lockingX(blr);
 507                 default:
 508                         DEBUG(0,("blocking_lock_record_process: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 509                         exit_server("PANIC - unknown type on blocking lock queue");
 510         }
 511         return False; /* Keep compiler happy. */
 512 }
 513
 514 /****************************************************************************
 515  Delete entries by fnum from the blocking lock pending queue.
 516 *****************************************************************************/
 517
 518 void remove_pending_lock_requests_by_fid(files_struct *fsp)
 519 {
 520         blocking_lock_record *blr, *next = NULL;
 521
 522         for(blr = blocking_lock_queue; blr; blr = next) {
 523                 next = blr->next;
 524                 if(blr->fsp->fnum == fsp->fnum) {
 525
 526                         DEBUG(10,("remove_pending_lock_requests_by_fid - removing request type %d for \
 527 file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
 528
 529                         brl_unlock(blr->fsp->dev, blr->fsp->inode, blr->fsp->fnum,
 530                                 blr->lock_pid, procid_self(), blr->fsp->conn->cnum,
 531                                 blr->offset, blr->count, True, NULL, NULL);
 532
 533                         free_blocking_lock_record(blr);
 534                 }
 535         }
 536 }
 537
 538 /****************************************************************************
 539  Delete entries by mid from the blocking lock pending queue. Always send reply.
 540 *****************************************************************************/
 541
 542 void remove_pending_lock_requests_by_mid(int mid)
 543 {
 544         blocking_lock_record *blr, *next = NULL;
 545
 546         for(blr = blocking_lock_queue; blr; blr = next) {
 547                 next = blr->next;
 548                 if(SVAL(blr->inbuf,smb_mid) == mid) {
 549                         files_struct *fsp = blr->fsp;
 550
 551                         DEBUG(10,("remove_pending_lock_requests_by_mid - removing request type %d for \
 552 file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
 553
 554                         blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
 555                         brl_unlock(blr->fsp->dev, blr->fsp->inode, blr->fsp->fnum,
 556                                 blr->lock_pid, procid_self(), blr->fsp->conn->cnum,
 557                                 blr->offset, blr->count, True, NULL, NULL);
 558                         free_blocking_lock_record(blr);
 559                 }
 560         }
 561 }
 562
 563 /****************************************************************************
 564   Set a flag as an unlock request affects one of our pending locks.
 565 *****************************************************************************/
 566
 567 static void received_unlock_msg(int msg_type, struct process_id src,
 568                                 void *buf, size_t len)
 569 {
 570         DEBUG(10,("received_unlock_msg\n"));
 571         process_blocking_lock_queue(time(NULL));
 572 }
 573
 574 /****************************************************************************
 575  Return the number of seconds to the next blocking locks timeout, or default_timeout
 576 *****************************************************************************/
 577
 578 unsigned blocking_locks_timeout(unsigned default_timeout)
 579 {
 580         unsigned timeout = default_timeout;
 581         time_t t;
 582         blocking_lock_record *blr = blocking_lock_queue;
 583
 584         /* note that we avoid the time() syscall if there are no blocking locks */
 585         if (!blr)
 586                 return timeout;
 587
 588         t = time(NULL);
 589
 590         for (; blr; blr = blr->next) {
 591                 if ((blr->expire_time != (time_t)-1) &&
 592                                         (timeout > (blr->expire_time - t))) {
 593                         timeout = blr->expire_time - t;
 594                 }
 595         }
 596
 597         if (timeout < 1)
 598                 timeout = 1;
 599
 600         return timeout;
 601 }
 602
 603 /****************************************************************************
 604  Process the blocking lock queue. Note that this is only called as root.
 605 *****************************************************************************/
 606
 607 void process_blocking_lock_queue(time_t t)
 608 {
 609         blocking_lock_record *blr, *next = NULL;
 610
 611         /*
 612          * Go through the queue and see if we can get any of the locks.
 613          */
 614
 615         for (blr = blocking_lock_queue; blr; blr = next) {
 616                 connection_struct *conn = NULL;
 617                 uint16 vuid;
 618                 files_struct *fsp = NULL;
 619
 620                 next = blr->next;
 621
 622                 /*
 623                  * Ensure we don't have any old chain_fsp values
 624                  * sitting around....
 625                  */
 626                 chain_size = 0;
 627                 file_chain_reset();
 628                 fsp = blr->fsp;
 629
 630                 conn = conn_find(SVAL(blr->inbuf,smb_tid));
 631                 vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID :
 632                                 SVAL(blr->inbuf,smb_uid);
 633
 634                 DEBUG(5,("process_blocking_lock_queue: examining pending lock fnum = %d for file %s\n",
 635                         fsp->fnum, fsp->fsp_name ));
 636
 637                 if((blr->expire_time != -1) && (blr->expire_time <= t)) {
 638                         /*
 639                          * Lock expired - throw away all previously
 640                          * obtained locks and return lock error.
 641                          */
 642                         DEBUG(5,("process_blocking_lock_queue: pending lock fnum = %d for file %s timed out.\n",
 643                                 fsp->fnum, fsp->fsp_name ));
 644
 645                         brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
 646                                 blr->lock_pid, procid_self(), conn->cnum,
 647                                 blr->offset, blr->count, True, NULL, NULL);
 648
 649                         blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
 650                         free_blocking_lock_record(blr);
 651                         continue;
 652                 }
 653
 654                 if(!change_to_user(conn,vuid)) {
 655                         DEBUG(0,("process_blocking_lock_queue: Unable to become user vuid=%d.\n",
 656                                 vuid ));
 657                         /*
 658                          * Remove the entry and return an error to the client.
 659                          */
 660                         blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
 661
 662                         brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
 663                                         blr->lock_pid, procid_self(), conn->cnum,
 664                                         blr->offset, blr->count, True, NULL, NULL);
 665
 666                         free_blocking_lock_record(blr);
 667                         continue;
 668                 }
 669
 670                 if(!set_current_service(conn,SVAL(blr->inbuf,smb_flg),True)) {
 671                         DEBUG(0,("process_blocking_lock_queue: Unable to become service Error was %s.\n", strerror(errno) ));
 672                         /*
 673                          * Remove the entry and return an error to the client.
 674                          */
 675                         blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
 676
 677                         brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
 678                                         blr->lock_pid, procid_self(), conn->cnum,
 679                                         blr->offset, blr->count, True, NULL, NULL);
 680
 681                         free_blocking_lock_record(blr);
 682                         change_to_root_user();
 683                         continue;
 684                 }
 685
 686                 /*
 687                  * Go through the remaining locks and try and obtain them.
 688                  * The call returns True if all locks were obtained successfully
 689                  * and False if we still need to wait.
 690                  */
 691
 692                 if(blocking_lock_record_process(blr)) {
 693
 694                         brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
 695                                         blr->lock_pid, procid_self(), conn->cnum,
 696                                         blr->offset, blr->count, True, NULL, NULL);
 697
 698                         free_blocking_lock_record(blr);
 699                 }
 700                 change_to_root_user();
 701         }
 702 }