source3/smbd/smb2_read.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Core SMB2 server
   4
   5    Copyright (C) Stefan Metzmacher 2009
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "system/filesys.h"
  23 #include "smbd/smbd.h"
  24 #include "smbd/globals.h"
  25 #include "../libcli/smb/smb_common.h"
  26 #include "libcli/security/security.h"
  27 #include "../lib/util/tevent_ntstatus.h"
  28 #include "rpc_server/srv_pipe_hnd.h"
  29
  30 static struct tevent_req *smbd_smb2_read_send(TALLOC_CTX *mem_ctx,
  31                                               struct tevent_context *ev,
  32                                               struct smbd_smb2_request *smb2req,
  33                                               struct files_struct *in_fsp,
  34                                               uint32_t in_length,
  35                                               uint64_t in_offset,
  36                                               uint32_t in_minimum,
  37                                               uint32_t in_remaining);
  38 static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req,
  39                                     TALLOC_CTX *mem_ctx,
  40                                     DATA_BLOB *out_data,
  41                                     uint32_t *out_remaining);
  42
  43 static void smbd_smb2_request_read_done(struct tevent_req *subreq);
  44 NTSTATUS smbd_smb2_request_process_read(struct smbd_smb2_request *req)
  45 {
  46         NTSTATUS status;
  47         const uint8_t *inbody;
  48         uint32_t in_length;
  49         uint64_t in_offset;
  50         uint64_t in_file_id_persistent;
  51         uint64_t in_file_id_volatile;
  52         struct files_struct *in_fsp;
  53         uint32_t in_minimum_count;
  54         uint32_t in_remaining_bytes;
  55         struct tevent_req *subreq;
  56
  57         status = smbd_smb2_request_verify_sizes(req, 0x31);
  58         if (!NT_STATUS_IS_OK(status)) {
  59                 return smbd_smb2_request_error(req, status);
  60         }
  61         inbody = SMBD_SMB2_IN_BODY_PTR(req);
  62
  63         in_length               = IVAL(inbody, 0x04);
  64         in_offset               = BVAL(inbody, 0x08);
  65         in_file_id_persistent   = BVAL(inbody, 0x10);
  66         in_file_id_volatile     = BVAL(inbody, 0x18);
  67         in_minimum_count        = IVAL(inbody, 0x20);
  68         in_remaining_bytes      = IVAL(inbody, 0x28);
  69
  70         /* check the max read size */
  71         if (in_length > req->sconn->smb2.max_read) {
  72                 DEBUG(2,("smbd_smb2_request_process_read: "
  73                          "client ignored max read: %s: 0x%08X: 0x%08X\n",
  74                         __location__, in_length, req->sconn->smb2.max_read));
  75                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  76         }
  77
  78         status = smbd_smb2_request_verify_creditcharge(req, in_length);
  79         if (!NT_STATUS_IS_OK(status)) {
  80                 return smbd_smb2_request_error(req, status);
  81         }
  82
  83         in_fsp = file_fsp_smb2(req, in_file_id_persistent, in_file_id_volatile);
  84         if (in_fsp == NULL) {
  85                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  86         }
  87
  88         subreq = smbd_smb2_read_send(req, req->sconn->ev_ctx,
  89                                      req, in_fsp,
  90                                      in_length,
  91                                      in_offset,
  92                                      in_minimum_count,
  93                                      in_remaining_bytes);
  94         if (subreq == NULL) {
  95                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
  96         }
  97         tevent_req_set_callback(subreq, smbd_smb2_request_read_done, req);
  98
  99         return smbd_smb2_request_pending_queue(req, subreq, 500);
 100 }
 101
 102 static void smbd_smb2_request_read_done(struct tevent_req *subreq)
 103 {
 104         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 105                                         struct smbd_smb2_request);
 106         DATA_BLOB outbody;
 107         DATA_BLOB outdyn;
 108         uint8_t out_data_offset;
 109         DATA_BLOB out_data_buffer = data_blob_null;
 110         uint32_t out_data_remaining = 0;
 111         NTSTATUS status;
 112         NTSTATUS error; /* transport error */
 113
 114         status = smbd_smb2_read_recv(subreq,
 115                                      req,
 116                                      &out_data_buffer,
 117                                      &out_data_remaining);
 118         TALLOC_FREE(subreq);
 119         if (!NT_STATUS_IS_OK(status)) {
 120                 error = smbd_smb2_request_error(req, status);
 121                 if (!NT_STATUS_IS_OK(error)) {
 122                         smbd_server_connection_terminate(req->sconn,
 123                                                          nt_errstr(error));
 124                         return;
 125                 }
 126                 return;
 127         }
 128
 129         out_data_offset = SMB2_HDR_BODY + 0x10;
 130
 131         outbody = smbd_smb2_generate_outbody(req, 0x10);
 132         if (outbody.data == NULL) {
 133                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 134                 if (!NT_STATUS_IS_OK(error)) {
 135                         smbd_server_connection_terminate(req->sconn,
 136                                                          nt_errstr(error));
 137                         return;
 138                 }
 139                 return;
 140         }
 141
 142         SSVAL(outbody.data, 0x00, 0x10 + 1);    /* struct size */
 143         SCVAL(outbody.data, 0x02,
 144               out_data_offset);                 /* data offset */
 145         SCVAL(outbody.data, 0x03, 0);           /* reserved */
 146         SIVAL(outbody.data, 0x04,
 147               out_data_buffer.length);          /* data length */
 148         SIVAL(outbody.data, 0x08,
 149               out_data_remaining);              /* data remaining */
 150         SIVAL(outbody.data, 0x0C, 0);           /* reserved */
 151
 152         outdyn = out_data_buffer;
 153
 154         error = smbd_smb2_request_done(req, outbody, &outdyn);
 155         if (!NT_STATUS_IS_OK(error)) {
 156                 smbd_server_connection_terminate(req->sconn,
 157                                                  nt_errstr(error));
 158                 return;
 159         }
 160 }
 161
 162 struct smbd_smb2_read_state {
 163         struct smbd_smb2_request *smb2req;
 164         struct smb_request *smbreq;
 165         files_struct *fsp;
 166         uint32_t in_length;
 167         uint64_t in_offset;
 168         uint32_t in_minimum;
 169         DATA_BLOB out_headers;
 170         uint8_t _out_hdr_buf[NBT_HDR_SIZE + SMB2_HDR_BODY + 0x10];
 171         DATA_BLOB out_data;
 172         uint32_t out_remaining;
 173 };
 174
 175 static int smb2_smb2_read_state_deny_destructor(struct smbd_smb2_read_state *state)
 176 {
 177         return -1;
 178 }
 179
 180 /* struct smbd_smb2_read_state destructor. Send the SMB2_READ data. */
 181 static int smb2_sendfile_send_data(struct smbd_smb2_read_state *state)
 182 {
 183         struct lock_struct lock;
 184         uint32_t in_length = state->in_length;
 185         uint64_t in_offset = state->in_offset;
 186         files_struct *fsp = state->fsp;
 187         const DATA_BLOB *hdr = state->smb2req->queue_entry.sendfile_header;
 188         struct smbXsrv_connection *xconn = state->smb2req->sconn->conn;
 189         ssize_t nread;
 190         ssize_t ret;
 191         int saved_errno;
 192
 193         nread = SMB_VFS_SENDFILE(fsp->conn->sconn->sock,
 194                                  fsp,
 195                                  hdr,
 196                                  in_offset,
 197                                  in_length);
 198         DEBUG(10,("smb2_sendfile_send_data: SMB_VFS_SENDFILE returned %d on file %s\n",
 199                 (int)nread,
 200                 fsp_str_dbg(fsp) ));
 201
 202         if (nread == -1) {
 203                 saved_errno = errno;
 204
 205                 /*
 206                  * Returning ENOSYS means no data at all was sent.
 207                    Do this as a normal read. */
 208                 if (errno == ENOSYS) {
 209                         goto normal_read;
 210                 }
 211
 212                 if (errno == EINTR) {
 213                         /*
 214                          * Special hack for broken Linux with no working sendfile. If we
 215                          * return EINTR we sent the header but not the rest of the data.
 216                          * Fake this up by doing read/write calls.
 217                          */
 218                         set_use_sendfile(SNUM(fsp->conn), false);
 219                         nread = fake_sendfile(fsp, in_offset, in_length);
 220                         if (nread == -1) {
 221                                 saved_errno = errno;
 222                                 DEBUG(0,("smb2_sendfile_send_data: fake_sendfile "
 223                                          "failed for file %s (%s) for client %s. "
 224                                          "Terminating\n",
 225                                          fsp_str_dbg(fsp), strerror(saved_errno),
 226                                          smbXsrv_connection_dbg(xconn)));
 227                                 exit_server_cleanly("smb2_sendfile_send_data: "
 228                                         "fake_sendfile failed");
 229                         }
 230                         goto out;
 231                 }
 232
 233                 DEBUG(0,("smb2_sendfile_send_data: sendfile failed for file "
 234                          "%s (%s) for client %s. Terminating\n",
 235                          fsp_str_dbg(fsp), strerror(saved_errno),
 236                          smbXsrv_connection_dbg(xconn)));
 237                 exit_server_cleanly("smb2_sendfile_send_data: sendfile failed");
 238         } else if (nread == 0) {
 239                 /*
 240                  * Some sendfile implementations return 0 to indicate
 241                  * that there was a short read, but nothing was
 242                  * actually written to the socket.  In this case,
 243                  * fallback to the normal read path so the header gets
 244                  * the correct byte count.
 245                  */
 246                 DEBUG(3, ("send_file_readX: sendfile sent zero bytes "
 247                         "falling back to the normal read: %s\n",
 248                         fsp_str_dbg(fsp)));
 249                 goto normal_read;
 250         }
 251
 252         /*
 253          * We got a short read
 254          */
 255         goto out;
 256
 257 normal_read:
 258         /* Send out the header. */
 259         ret = write_data(fsp->conn->sconn->sock,
 260                          (const char *)hdr->data, hdr->length);
 261         if (ret != hdr->length) {
 262                 saved_errno = errno;
 263                 DEBUG(0,("smb2_sendfile_send_data: write_data failed for file "
 264                          "%s (%s) for client %s. Terminating\n",
 265                          fsp_str_dbg(fsp), strerror(saved_errno),
 266                          smbXsrv_connection_dbg(xconn)));
 267                 exit_server_cleanly("smb2_sendfile_send_data: write_data failed");
 268         }
 269         nread = fake_sendfile(fsp, in_offset, in_length);
 270         if (nread == -1) {
 271                 saved_errno = errno;
 272                 DEBUG(0,("smb2_sendfile_send_data: fake_sendfile "
 273                          "failed for file %s (%s) for client %s. "
 274                          "Terminating\n",
 275                          fsp_str_dbg(fsp), strerror(saved_errno),
 276                          smbXsrv_connection_dbg(xconn)));
 277                 exit_server_cleanly("smb2_sendfile_send_data: "
 278                         "fake_sendfile failed");
 279         }
 280
 281   out:
 282
 283         if (nread < in_length) {
 284                 sendfile_short_send(fsp, nread, hdr->length, in_length);
 285         }
 286
 287         init_strict_lock_struct(fsp,
 288                                 fsp->op->global->open_persistent_id,
 289                                 in_offset,
 290                                 in_length,
 291                                 READ_LOCK,
 292                                 &lock);
 293
 294         SMB_VFS_STRICT_UNLOCK(fsp->conn, fsp, &lock);
 295         return 0;
 296 }
 297
 298 static NTSTATUS schedule_smb2_sendfile_read(struct smbd_smb2_request *smb2req,
 299                                         struct smbd_smb2_read_state *state)
 300 {
 301         files_struct *fsp = state->fsp;
 302
 303         /*
 304          * We cannot use sendfile if...
 305          * We were not configured to do so OR
 306          * Signing is active OR
 307          * This is a compound SMB2 operation OR
 308          * fsp is a STREAM file OR
 309          * We're using a write cache OR
 310          * It's not a regular file OR
 311          * Requested offset is greater than file size OR
 312          * there's not enough data in the file.
 313          * Phew :-). Luckily this means most
 314          * reads on most normal files. JRA.
 315         */
 316
 317         if (!lp__use_sendfile(SNUM(fsp->conn)) ||
 318             smb2req->do_signing ||
 319             smb2req->do_encryption ||
 320             smb2req->in.vector_count >= (2*SMBD_SMB2_NUM_IOV_PER_REQ) ||
 321             (fsp->base_fsp != NULL) ||
 322             (fsp->wcp != NULL) ||
 323             (!S_ISREG(fsp->fsp_name->st.st_ex_mode)) ||
 324             (state->in_offset >= fsp->fsp_name->st.st_ex_size) ||
 325             (fsp->fsp_name->st.st_ex_size < state->in_offset + state->in_length))
 326         {
 327                 return NT_STATUS_RETRY;
 328         }
 329
 330         /* We've already checked there's this amount of data
 331            to read. */
 332         state->out_data.length = state->in_length;
 333         state->out_remaining = 0;
 334
 335         state->out_headers = data_blob_const(state->_out_hdr_buf,
 336                                              sizeof(state->_out_hdr_buf));
 337         return NT_STATUS_OK;
 338 }
 339
 340 static void smbd_smb2_read_pipe_done(struct tevent_req *subreq);
 341
 342 /*******************************************************************
 343  Common read complete processing function for both synchronous and
 344  asynchronous reads.
 345 *******************************************************************/
 346
 347 NTSTATUS smb2_read_complete(struct tevent_req *req, ssize_t nread, int err)
 348 {
 349         struct smbd_smb2_read_state *state = tevent_req_data(req,
 350                                         struct smbd_smb2_read_state);
 351         files_struct *fsp = state->fsp;
 352
 353         if (nread < 0) {
 354                 NTSTATUS status = map_nt_error_from_unix(err);
 355
 356                 DEBUG( 3,( "smb2_read_complete: file %s nread = %d. "
 357                         "Error = %s (NTSTATUS %s)\n",
 358                         fsp_str_dbg(fsp),
 359                         (int)nread,
 360                         strerror(err),
 361                         nt_errstr(status)));
 362
 363                 return status;
 364         }
 365         if (nread == 0 && state->in_length != 0) {
 366                 DEBUG(5,("smb2_read_complete: read_file[%s] end of file\n",
 367                         fsp_str_dbg(fsp)));
 368                 return NT_STATUS_END_OF_FILE;
 369         }
 370
 371         if (nread < state->in_minimum) {
 372                 DEBUG(5,("smb2_read_complete: read_file[%s] read less %d than "
 373                         "minimum requested %u. Returning end of file\n",
 374                         fsp_str_dbg(fsp),
 375                         (int)nread,
 376                         (unsigned int)state->in_minimum));
 377                 return NT_STATUS_END_OF_FILE;
 378         }
 379
 380         DEBUG(3,("smbd_smb2_read: %s, file %s, length=%lu offset=%lu read=%lu\n",
 381                 fsp_fnum_dbg(fsp),
 382                 fsp_str_dbg(fsp),
 383                 (unsigned long)state->in_length,
 384                 (unsigned long)state->in_offset,
 385                 (unsigned long)nread));
 386
 387         state->out_data.length = nread;
 388         state->out_remaining = 0;
 389
 390         return NT_STATUS_OK;
 391 }
 392
 393 static bool smbd_smb2_read_cancel(struct tevent_req *req)
 394 {
 395         struct smbd_smb2_read_state *state =
 396                 tevent_req_data(req,
 397                 struct smbd_smb2_read_state);
 398
 399         return cancel_smb2_aio(state->smbreq);
 400 }
 401
 402 static struct tevent_req *smbd_smb2_read_send(TALLOC_CTX *mem_ctx,
 403                                               struct tevent_context *ev,
 404                                               struct smbd_smb2_request *smb2req,
 405                                               struct files_struct *fsp,
 406                                               uint32_t in_length,
 407                                               uint64_t in_offset,
 408                                               uint32_t in_minimum,
 409                                               uint32_t in_remaining)
 410 {
 411         NTSTATUS status;
 412         struct tevent_req *req = NULL;
 413         struct smbd_smb2_read_state *state = NULL;
 414         struct smb_request *smbreq = NULL;
 415         connection_struct *conn = smb2req->tcon->compat;
 416         ssize_t nread = -1;
 417         struct lock_struct lock;
 418         int saved_errno;
 419
 420         req = tevent_req_create(mem_ctx, &state,
 421                                 struct smbd_smb2_read_state);
 422         if (req == NULL) {
 423                 return NULL;
 424         }
 425         state->smb2req = smb2req;
 426         state->in_length = in_length;
 427         state->in_offset = in_offset;
 428         state->in_minimum = in_minimum;
 429         state->out_data = data_blob_null;
 430         state->out_remaining = 0;
 431
 432         DEBUG(10,("smbd_smb2_read: %s - %s\n",
 433                   fsp_str_dbg(fsp), fsp_fnum_dbg(fsp)));
 434
 435         smbreq = smbd_smb2_fake_smb_request(smb2req);
 436         if (tevent_req_nomem(smbreq, req)) {
 437                 return tevent_req_post(req, ev);
 438         }
 439         state->smbreq = smbreq;
 440
 441         if (fsp->is_directory) {
 442                 tevent_req_nterror(req, NT_STATUS_INVALID_DEVICE_REQUEST);
 443                 return tevent_req_post(req, ev);
 444         }
 445
 446         state->fsp = fsp;
 447
 448         if (IS_IPC(smbreq->conn)) {
 449                 struct tevent_req *subreq = NULL;
 450
 451                 state->out_data = data_blob_talloc(state, NULL, in_length);
 452                 if (in_length > 0 && tevent_req_nomem(state->out_data.data, req)) {
 453                         return tevent_req_post(req, ev);
 454                 }
 455
 456                 if (!fsp_is_np(fsp)) {
 457                         tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 458                         return tevent_req_post(req, ev);
 459                 }
 460
 461                 subreq = np_read_send(state, ev,
 462                                       fsp->fake_file_handle,
 463                                       state->out_data.data,
 464                                       state->out_data.length);
 465                 if (tevent_req_nomem(subreq, req)) {
 466                         return tevent_req_post(req, ev);
 467                 }
 468                 tevent_req_set_callback(subreq,
 469                                         smbd_smb2_read_pipe_done,
 470                                         req);
 471                 return req;
 472         }
 473
 474         if (!CHECK_READ(fsp, smbreq)) {
 475                 tevent_req_nterror(req, NT_STATUS_ACCESS_DENIED);
 476                 return tevent_req_post(req, ev);
 477         }
 478
 479         status = schedule_smb2_aio_read(fsp->conn,
 480                                 smbreq,
 481                                 fsp,
 482                                 state,
 483                                 &state->out_data,
 484                                 (off_t)in_offset,
 485                                 (size_t)in_length);
 486
 487         if (NT_STATUS_IS_OK(status)) {
 488                 /*
 489                  * Doing an async read, allow this
 490                  * request to be canceled
 491                  */
 492                 tevent_req_set_cancel_fn(req, smbd_smb2_read_cancel);
 493                 return req;
 494         }
 495
 496         if (!NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
 497                 /* Real error in setting up aio. Fail. */
 498                 tevent_req_nterror(req, status);
 499                 return tevent_req_post(req, ev);
 500         }
 501
 502         /* Fallback to synchronous. */
 503
 504         init_strict_lock_struct(fsp,
 505                                 fsp->op->global->open_persistent_id,
 506                                 in_offset,
 507                                 in_length,
 508                                 READ_LOCK,
 509                                 &lock);
 510
 511         if (!SMB_VFS_STRICT_LOCK(conn, fsp, &lock)) {
 512                 tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
 513                 return tevent_req_post(req, ev);
 514         }
 515
 516         /* Try sendfile in preference. */
 517         status = schedule_smb2_sendfile_read(smb2req, state);
 518         if (NT_STATUS_IS_OK(status)) {
 519                 tevent_req_done(req);
 520                 return tevent_req_post(req, ev);
 521         } else {
 522                 if (!NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
 523                         SMB_VFS_STRICT_UNLOCK(conn, fsp, &lock);
 524                         tevent_req_nterror(req, status);
 525                         return tevent_req_post(req, ev);
 526                 }
 527         }
 528
 529         /* Ok, read into memory. Allocate the out buffer. */
 530         state->out_data = data_blob_talloc(state, NULL, in_length);
 531         if (in_length > 0 && tevent_req_nomem(state->out_data.data, req)) {
 532                 SMB_VFS_STRICT_UNLOCK(conn, fsp, &lock);
 533                 return tevent_req_post(req, ev);
 534         }
 535
 536         nread = read_file(fsp,
 537                           (char *)state->out_data.data,
 538                           in_offset,
 539                           in_length);
 540
 541         saved_errno = errno;
 542
 543         SMB_VFS_STRICT_UNLOCK(conn, fsp, &lock);
 544
 545         DEBUG(10,("smbd_smb2_read: file %s, %s, offset=%llu "
 546                 "len=%llu returned %lld\n",
 547                 fsp_str_dbg(fsp),
 548                 fsp_fnum_dbg(fsp),
 549                 (unsigned long long)in_offset,
 550                 (unsigned long long)in_length,
 551                 (long long)nread));
 552
 553         status = smb2_read_complete(req, nread, saved_errno);
 554         if (!NT_STATUS_IS_OK(status)) {
 555                 tevent_req_nterror(req, status);
 556         } else {
 557                 /* Success. */
 558                 tevent_req_done(req);
 559         }
 560         return tevent_req_post(req, ev);
 561 }
 562
 563 static void smbd_smb2_read_pipe_done(struct tevent_req *subreq)
 564 {
 565         struct tevent_req *req = tevent_req_callback_data(subreq,
 566                                  struct tevent_req);
 567         struct smbd_smb2_read_state *state = tevent_req_data(req,
 568                                              struct smbd_smb2_read_state);
 569         NTSTATUS status;
 570         ssize_t nread = -1;
 571         bool is_data_outstanding;
 572
 573         status = np_read_recv(subreq, &nread, &is_data_outstanding);
 574         TALLOC_FREE(subreq);
 575         if (!NT_STATUS_IS_OK(status)) {
 576                 NTSTATUS old = status;
 577                 status = nt_status_np_pipe(old);
 578                 tevent_req_nterror(req, status);
 579                 return;
 580         }
 581
 582         if (nread == 0 && state->out_data.length != 0) {
 583                 tevent_req_nterror(req, NT_STATUS_END_OF_FILE);
 584                 return;
 585         }
 586
 587         state->out_data.length = nread;
 588         state->out_remaining = 0;
 589
 590         /*
 591          * TODO: add STATUS_BUFFER_OVERFLOW handling, once we also
 592          * handle it in SMB1 pipe_read_andx_done().
 593          */
 594
 595         tevent_req_done(req);
 596 }
 597
 598 static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req,
 599                                     TALLOC_CTX *mem_ctx,
 600                                     DATA_BLOB *out_data,
 601                                     uint32_t *out_remaining)
 602 {
 603         NTSTATUS status;
 604         struct smbd_smb2_read_state *state = tevent_req_data(req,
 605                                              struct smbd_smb2_read_state);
 606
 607         if (tevent_req_is_nterror(req, &status)) {
 608                 tevent_req_received(req);
 609                 return status;
 610         }
 611
 612         *out_data = state->out_data;
 613         talloc_steal(mem_ctx, out_data->data);
 614         *out_remaining = state->out_remaining;
 615
 616         if (state->out_headers.length > 0) {
 617                 talloc_steal(mem_ctx, state);
 618                 talloc_set_destructor(state, smb2_smb2_read_state_deny_destructor);
 619                 tevent_req_received(req);
 620                 state->smb2req->queue_entry.sendfile_header = &state->out_headers;
 621                 talloc_set_destructor(state, smb2_sendfile_send_data);
 622         } else {
 623                 tevent_req_received(req);
 624         }
 625
 626         return NT_STATUS_OK;
 627 }