fs/cifs/cifs_debug.c

   1 /*
   2  *   fs/cifs_debug.c
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2000,2005
   5  *
   6  *   Modified by Steve French (sfrench@us.ibm.com)
   7  *
   8  *   This program is free software;  you can redistribute it and/or modify
   9  *   it under the terms of the GNU General Public License as published by
  10  *   the Free Software Foundation; either version 2 of the License, or
  11  *   (at your option) any later version.
  12  *
  13  *   This program is distributed in the hope that it will be useful,
  14  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  16  *   the GNU General Public License for more details.
  17  *
  18  *   You should have received a copy of the GNU General Public License
  19  *   along with this program;  if not, write to the Free Software
  20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21  */
  22 #include <linux/fs.h>
  23 #include <linux/string.h>
  24 #include <linux/ctype.h>
  25 #include <linux/module.h>
  26 #include <linux/proc_fs.h>
  27 #include <asm/uaccess.h>
  28 #include "cifspdu.h"
  29 #include "cifsglob.h"
  30 #include "cifsproto.h"
  31 #include "cifs_debug.h"
  32 #include "cifsfs.h"
  33
  34 void
  35 cifs_dump_mem(char *label, void *data, int length)
  36 {
  37         pr_debug("%s: dump of %d bytes of data at 0x%p\n", label, length, data);
  38         print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 16, 4,
  39                        data, length, true);
  40 }
  41
  42 #ifdef CONFIG_CIFS_DEBUG
  43 void cifs_vfs_err(const char *fmt, ...)
  44 {
  45         struct va_format vaf;
  46         va_list args;
  47
  48         va_start(args, fmt);
  49
  50         vaf.fmt = fmt;
  51         vaf.va = &args;
  52
  53         pr_err_ratelimited("CIFS VFS: %pV", &vaf);
  54
  55         va_end(args);
  56 }
  57 #endif
  58
  59 void cifs_dump_detail(void *buf)
  60 {
  61 #ifdef CONFIG_CIFS_DEBUG2
  62         struct smb_hdr *smb = (struct smb_hdr *)buf;
  63
  64         cifs_dbg(VFS, "Cmd: %d Err: 0x%x Flags: 0x%x Flgs2: 0x%x Mid: %d Pid: %d\n",
  65                  smb->Command, smb->Status.CifsError,
  66                  smb->Flags, smb->Flags2, smb->Mid, smb->Pid);
  67         cifs_dbg(VFS, "smb buf %p len %u\n", smb, smbCalcSize(smb));
  68 #endif /* CONFIG_CIFS_DEBUG2 */
  69 }
  70
  71 void cifs_dump_mids(struct TCP_Server_Info *server)
  72 {
  73 #ifdef CONFIG_CIFS_DEBUG2
  74         struct list_head *tmp;
  75         struct mid_q_entry *mid_entry;
  76
  77         if (server == NULL)
  78                 return;
  79
  80         cifs_dbg(VFS, "Dump pending requests:\n");
  81         spin_lock(&GlobalMid_Lock);
  82         list_for_each(tmp, &server->pending_mid_q) {
  83                 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
  84                 cifs_dbg(VFS, "State: %d Cmd: %d Pid: %d Cbdata: %p Mid %llu\n",
  85                          mid_entry->mid_state,
  86                          le16_to_cpu(mid_entry->command),
  87                          mid_entry->pid,
  88                          mid_entry->callback_data,
  89                          mid_entry->mid);
  90 #ifdef CONFIG_CIFS_STATS2
  91                 cifs_dbg(VFS, "IsLarge: %d buf: %p time rcv: %ld now: %ld\n",
  92                          mid_entry->large_buf,
  93                          mid_entry->resp_buf,
  94                          mid_entry->when_received,
  95                          jiffies);
  96 #endif /* STATS2 */
  97                 cifs_dbg(VFS, "IsMult: %d IsEnd: %d\n",
  98                          mid_entry->multiRsp, mid_entry->multiEnd);
  99                 if (mid_entry->resp_buf) {
 100                         cifs_dump_detail(mid_entry->resp_buf);
 101                         cifs_dump_mem("existing buf: ",
 102                                 mid_entry->resp_buf, 62);
 103                 }
 104         }
 105         spin_unlock(&GlobalMid_Lock);
 106 #endif /* CONFIG_CIFS_DEBUG2 */
 107 }
 108
 109 #ifdef CONFIG_PROC_FS
 110 static int cifs_debug_data_proc_show(struct seq_file *m, void *v)
 111 {
 112         struct list_head *tmp1, *tmp2, *tmp3;
 113         struct mid_q_entry *mid_entry;
 114         struct TCP_Server_Info *server;
 115         struct cifs_ses *ses;
 116         struct cifs_tcon *tcon;
 117         int i, j;
 118         __u32 dev_type;
 119
 120         seq_puts(m,
 121                     "Display Internal CIFS Data Structures for Debugging\n"
 122                     "---------------------------------------------------\n");
 123         seq_printf(m, "CIFS Version %s\n", CIFS_VERSION);
 124         seq_printf(m, "Features:");
 125 #ifdef CONFIG_CIFS_DFS_UPCALL
 126         seq_printf(m, " dfs");
 127 #endif
 128 #ifdef CONFIG_CIFS_FSCACHE
 129         seq_printf(m, " fscache");
 130 #endif
 131 #ifdef CONFIG_CIFS_WEAK_PW_HASH
 132         seq_printf(m, " lanman");
 133 #endif
 134 #ifdef CONFIG_CIFS_POSIX
 135         seq_printf(m, " posix");
 136 #endif
 137 #ifdef CONFIG_CIFS_UPCALL
 138         seq_printf(m, " spnego");
 139 #endif
 140 #ifdef CONFIG_CIFS_XATTR
 141         seq_printf(m, " xattr");
 142 #endif
 143 #ifdef CONFIG_CIFS_ACL
 144         seq_printf(m, " acl");
 145 #endif
 146         seq_putc(m, '\n');
 147         seq_printf(m, "Active VFS Requests: %d\n", GlobalTotalActiveXid);
 148         seq_printf(m, "Servers:");
 149
 150         i = 0;
 151         spin_lock(&cifs_tcp_ses_lock);
 152         list_for_each(tmp1, &cifs_tcp_ses_list) {
 153                 server = list_entry(tmp1, struct TCP_Server_Info,
 154                                     tcp_ses_list);
 155                 seq_printf(m, "\nNumber of credits: %d", server->credits);
 156                 i++;
 157                 list_for_each(tmp2, &server->smb_ses_list) {
 158                         ses = list_entry(tmp2, struct cifs_ses,
 159                                          smb_ses_list);
 160                         if ((ses->serverDomain == NULL) ||
 161                                 (ses->serverOS == NULL) ||
 162                                 (ses->serverNOS == NULL)) {
 163                                 seq_printf(m, "\n%d) entry for %s not fully "
 164                                            "displayed\n\t", i, ses->serverName);
 165                         } else {
 166                                 seq_printf(m,
 167                                     "\n%d) Name: %s  Domain: %s Uses: %d OS:"
 168                                     " %s\n\tNOS: %s\tCapability: 0x%x\n\tSMB"
 169                                     " session status: %d\t",
 170                                 i, ses->serverName, ses->serverDomain,
 171                                 ses->ses_count, ses->serverOS, ses->serverNOS,
 172                                 ses->capabilities, ses->status);
 173                         }
 174                         seq_printf(m, "TCP status: %d\n\tLocal Users To "
 175                                    "Server: %d SecMode: 0x%x Req On Wire: %d",
 176                                    server->tcpStatus, server->srv_count,
 177                                    server->sec_mode, in_flight(server));
 178
 179 #ifdef CONFIG_CIFS_STATS2
 180                         seq_printf(m, " In Send: %d In MaxReq Wait: %d",
 181                                 atomic_read(&server->in_send),
 182                                 atomic_read(&server->num_waiters));
 183 #endif
 184
 185                         seq_puts(m, "\n\tShares:");
 186                         j = 0;
 187                         list_for_each(tmp3, &ses->tcon_list) {
 188                                 tcon = list_entry(tmp3, struct cifs_tcon,
 189                                                   tcon_list);
 190                                 ++j;
 191                                 dev_type = le32_to_cpu(tcon->fsDevInfo.DeviceType);
 192                                 seq_printf(m, "\n\t%d) %s Mounts: %d ", j,
 193                                            tcon->treeName, tcon->tc_count);
 194                                 if (tcon->nativeFileSystem) {
 195                                         seq_printf(m, "Type: %s ",
 196                                                    tcon->nativeFileSystem);
 197                                 }
 198                                 seq_printf(m, "DevInfo: 0x%x Attributes: 0x%x"
 199                                         "\n\tPathComponentMax: %d Status: %d",
 200                                         le32_to_cpu(tcon->fsDevInfo.DeviceCharacteristics),
 201                                         le32_to_cpu(tcon->fsAttrInfo.Attributes),
 202                                         le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength),
 203                                         tcon->tidStatus);
 204                                 if (dev_type == FILE_DEVICE_DISK)
 205                                         seq_puts(m, " type: DISK ");
 206                                 else if (dev_type == FILE_DEVICE_CD_ROM)
 207                                         seq_puts(m, " type: CDROM ");
 208                                 else
 209                                         seq_printf(m, " type: %d ", dev_type);
 210                                 if (server->ops->dump_share_caps)
 211                                         server->ops->dump_share_caps(m, tcon);
 212
 213                                 if (tcon->need_reconnect)
 214                                         seq_puts(m, "\tDISCONNECTED ");
 215                                 seq_putc(m, '\n');
 216                         }
 217
 218                         seq_puts(m, "\n\tMIDs:\n");
 219
 220                         spin_lock(&GlobalMid_Lock);
 221                         list_for_each(tmp3, &server->pending_mid_q) {
 222                                 mid_entry = list_entry(tmp3, struct mid_q_entry,
 223                                         qhead);
 224                                 seq_printf(m, "\tState: %d com: %d pid:"
 225                                               " %d cbdata: %p mid %llu\n",
 226                                               mid_entry->mid_state,
 227                                               le16_to_cpu(mid_entry->command),
 228                                               mid_entry->pid,
 229                                               mid_entry->callback_data,
 230                                               mid_entry->mid);
 231                         }
 232                         spin_unlock(&GlobalMid_Lock);
 233                 }
 234         }
 235         spin_unlock(&cifs_tcp_ses_lock);
 236         seq_putc(m, '\n');
 237
 238         /* BB add code to dump additional info such as TCP session info now */
 239         return 0;
 240 }
 241
 242 static int cifs_debug_data_proc_open(struct inode *inode, struct file *file)
 243 {
 244         return single_open(file, cifs_debug_data_proc_show, NULL);
 245 }
 246
 247 static const struct file_operations cifs_debug_data_proc_fops = {
 248         .open           = cifs_debug_data_proc_open,
 249         .read           = seq_read,
 250         .llseek         = seq_lseek,
 251         .release        = single_release,
 252 };
 253
 254 #ifdef CONFIG_CIFS_STATS
 255 static ssize_t cifs_stats_proc_write(struct file *file,
 256                 const char __user *buffer, size_t count, loff_t *ppos)
 257 {
 258         bool bv;
 259         int rc;
 260         struct list_head *tmp1, *tmp2, *tmp3;
 261         struct TCP_Server_Info *server;
 262         struct cifs_ses *ses;
 263         struct cifs_tcon *tcon;
 264
 265         rc = kstrtobool_from_user(buffer, count, &bv);
 266         if (rc == 0) {
 267 #ifdef CONFIG_CIFS_STATS2
 268                 atomic_set(&totBufAllocCount, 0);
 269                 atomic_set(&totSmBufAllocCount, 0);
 270 #endif /* CONFIG_CIFS_STATS2 */
 271                 spin_lock(&cifs_tcp_ses_lock);
 272                 list_for_each(tmp1, &cifs_tcp_ses_list) {
 273                         server = list_entry(tmp1, struct TCP_Server_Info,
 274                                             tcp_ses_list);
 275                         list_for_each(tmp2, &server->smb_ses_list) {
 276                                 ses = list_entry(tmp2, struct cifs_ses,
 277                                                  smb_ses_list);
 278                                 list_for_each(tmp3, &ses->tcon_list) {
 279                                         tcon = list_entry(tmp3,
 280                                                           struct cifs_tcon,
 281                                                           tcon_list);
 282                                         atomic_set(&tcon->num_smbs_sent, 0);
 283                                         if (server->ops->clear_stats)
 284                                                 server->ops->clear_stats(tcon);
 285                                 }
 286                         }
 287                 }
 288                 spin_unlock(&cifs_tcp_ses_lock);
 289         } else {
 290                 return rc;
 291         }
 292
 293         return count;
 294 }
 295
 296 static int cifs_stats_proc_show(struct seq_file *m, void *v)
 297 {
 298         int i;
 299         struct list_head *tmp1, *tmp2, *tmp3;
 300         struct TCP_Server_Info *server;
 301         struct cifs_ses *ses;
 302         struct cifs_tcon *tcon;
 303
 304         seq_printf(m,
 305                         "Resources in use\nCIFS Session: %d\n",
 306                         sesInfoAllocCount.counter);
 307         seq_printf(m, "Share (unique mount targets): %d\n",
 308                         tconInfoAllocCount.counter);
 309         seq_printf(m, "SMB Request/Response Buffer: %d Pool size: %d\n",
 310                         bufAllocCount.counter,
 311                         cifs_min_rcv + tcpSesAllocCount.counter);
 312         seq_printf(m, "SMB Small Req/Resp Buffer: %d Pool size: %d\n",
 313                         smBufAllocCount.counter, cifs_min_small);
 314 #ifdef CONFIG_CIFS_STATS2
 315         seq_printf(m, "Total Large %d Small %d Allocations\n",
 316                                 atomic_read(&totBufAllocCount),
 317                                 atomic_read(&totSmBufAllocCount));
 318 #endif /* CONFIG_CIFS_STATS2 */
 319
 320         seq_printf(m, "Operations (MIDs): %d\n", atomic_read(&midCount));
 321         seq_printf(m,
 322                 "\n%d session %d share reconnects\n",
 323                 tcpSesReconnectCount.counter, tconInfoReconnectCount.counter);
 324
 325         seq_printf(m,
 326                 "Total vfs operations: %d maximum at one time: %d\n",
 327                 GlobalCurrentXid, GlobalMaxActiveXid);
 328
 329         i = 0;
 330         spin_lock(&cifs_tcp_ses_lock);
 331         list_for_each(tmp1, &cifs_tcp_ses_list) {
 332                 server = list_entry(tmp1, struct TCP_Server_Info,
 333                                     tcp_ses_list);
 334                 list_for_each(tmp2, &server->smb_ses_list) {
 335                         ses = list_entry(tmp2, struct cifs_ses,
 336                                          smb_ses_list);
 337                         list_for_each(tmp3, &ses->tcon_list) {
 338                                 tcon = list_entry(tmp3,
 339                                                   struct cifs_tcon,
 340                                                   tcon_list);
 341                                 i++;
 342                                 seq_printf(m, "\n%d) %s", i, tcon->treeName);
 343                                 if (tcon->need_reconnect)
 344                                         seq_puts(m, "\tDISCONNECTED ");
 345                                 seq_printf(m, "\nSMBs: %d",
 346                                            atomic_read(&tcon->num_smbs_sent));
 347                                 if (server->ops->print_stats)
 348                                         server->ops->print_stats(m, tcon);
 349                         }
 350                 }
 351         }
 352         spin_unlock(&cifs_tcp_ses_lock);
 353
 354         seq_putc(m, '\n');
 355         return 0;
 356 }
 357
 358 static int cifs_stats_proc_open(struct inode *inode, struct file *file)
 359 {
 360         return single_open(file, cifs_stats_proc_show, NULL);
 361 }
 362
 363 static const struct file_operations cifs_stats_proc_fops = {
 364         .open           = cifs_stats_proc_open,
 365         .read           = seq_read,
 366         .llseek         = seq_lseek,
 367         .release        = single_release,
 368         .write          = cifs_stats_proc_write,
 369 };
 370 #endif /* STATS */
 371
 372 static struct proc_dir_entry *proc_fs_cifs;
 373 static const struct file_operations cifsFYI_proc_fops;
 374 static const struct file_operations cifs_lookup_cache_proc_fops;
 375 static const struct file_operations traceSMB_proc_fops;
 376 static const struct file_operations cifs_security_flags_proc_fops;
 377 static const struct file_operations cifs_linux_ext_proc_fops;
 378
 379 void
 380 cifs_proc_init(void)
 381 {
 382         proc_fs_cifs = proc_mkdir("fs/cifs", NULL);
 383         if (proc_fs_cifs == NULL)
 384                 return;
 385
 386         proc_create("DebugData", 0, proc_fs_cifs, &cifs_debug_data_proc_fops);
 387
 388 #ifdef CONFIG_CIFS_STATS
 389         proc_create("Stats", 0, proc_fs_cifs, &cifs_stats_proc_fops);
 390 #endif /* STATS */
 391         proc_create("cifsFYI", 0, proc_fs_cifs, &cifsFYI_proc_fops);
 392         proc_create("traceSMB", 0, proc_fs_cifs, &traceSMB_proc_fops);
 393         proc_create("LinuxExtensionsEnabled", 0, proc_fs_cifs,
 394                     &cifs_linux_ext_proc_fops);
 395         proc_create("SecurityFlags", 0, proc_fs_cifs,
 396                     &cifs_security_flags_proc_fops);
 397         proc_create("LookupCacheEnabled", 0, proc_fs_cifs,
 398                     &cifs_lookup_cache_proc_fops);
 399 }
 400
 401 void
 402 cifs_proc_clean(void)
 403 {
 404         if (proc_fs_cifs == NULL)
 405                 return;
 406
 407         remove_proc_entry("DebugData", proc_fs_cifs);
 408         remove_proc_entry("cifsFYI", proc_fs_cifs);
 409         remove_proc_entry("traceSMB", proc_fs_cifs);
 410 #ifdef CONFIG_CIFS_STATS
 411         remove_proc_entry("Stats", proc_fs_cifs);
 412 #endif
 413         remove_proc_entry("SecurityFlags", proc_fs_cifs);
 414         remove_proc_entry("LinuxExtensionsEnabled", proc_fs_cifs);
 415         remove_proc_entry("LookupCacheEnabled", proc_fs_cifs);
 416         remove_proc_entry("fs/cifs", NULL);
 417 }
 418
 419 static int cifsFYI_proc_show(struct seq_file *m, void *v)
 420 {
 421         seq_printf(m, "%d\n", cifsFYI);
 422         return 0;
 423 }
 424
 425 static int cifsFYI_proc_open(struct inode *inode, struct file *file)
 426 {
 427         return single_open(file, cifsFYI_proc_show, NULL);
 428 }
 429
 430 static ssize_t cifsFYI_proc_write(struct file *file, const char __user *buffer,
 431                 size_t count, loff_t *ppos)
 432 {
 433         char c[2] = { '\0' };
 434         bool bv;
 435         int rc;
 436
 437         rc = get_user(c[0], buffer);
 438         if (rc)
 439                 return rc;
 440         if (strtobool(c, &bv) == 0)
 441                 cifsFYI = bv;
 442         else if ((c[0] > '1') && (c[0] <= '9'))
 443                 cifsFYI = (int) (c[0] - '0'); /* see cifs_debug.h for meanings */
 444
 445         return count;
 446 }
 447
 448 static const struct file_operations cifsFYI_proc_fops = {
 449         .open           = cifsFYI_proc_open,
 450         .read           = seq_read,
 451         .llseek         = seq_lseek,
 452         .release        = single_release,
 453         .write          = cifsFYI_proc_write,
 454 };
 455
 456 static int cifs_linux_ext_proc_show(struct seq_file *m, void *v)
 457 {
 458         seq_printf(m, "%d\n", linuxExtEnabled);
 459         return 0;
 460 }
 461
 462 static int cifs_linux_ext_proc_open(struct inode *inode, struct file *file)
 463 {
 464         return single_open(file, cifs_linux_ext_proc_show, NULL);
 465 }
 466
 467 static ssize_t cifs_linux_ext_proc_write(struct file *file,
 468                 const char __user *buffer, size_t count, loff_t *ppos)
 469 {
 470         int rc;
 471
 472         rc = kstrtobool_from_user(buffer, count, &linuxExtEnabled);
 473         if (rc)
 474                 return rc;
 475
 476         return count;
 477 }
 478
 479 static const struct file_operations cifs_linux_ext_proc_fops = {
 480         .open           = cifs_linux_ext_proc_open,
 481         .read           = seq_read,
 482         .llseek         = seq_lseek,
 483         .release        = single_release,
 484         .write          = cifs_linux_ext_proc_write,
 485 };
 486
 487 static int cifs_lookup_cache_proc_show(struct seq_file *m, void *v)
 488 {
 489         seq_printf(m, "%d\n", lookupCacheEnabled);
 490         return 0;
 491 }
 492
 493 static int cifs_lookup_cache_proc_open(struct inode *inode, struct file *file)
 494 {
 495         return single_open(file, cifs_lookup_cache_proc_show, NULL);
 496 }
 497
 498 static ssize_t cifs_lookup_cache_proc_write(struct file *file,
 499                 const char __user *buffer, size_t count, loff_t *ppos)
 500 {
 501         int rc;
 502
 503         rc = kstrtobool_from_user(buffer, count, &lookupCacheEnabled);
 504         if (rc)
 505                 return rc;
 506
 507         return count;
 508 }
 509
 510 static const struct file_operations cifs_lookup_cache_proc_fops = {
 511         .open           = cifs_lookup_cache_proc_open,
 512         .read           = seq_read,
 513         .llseek         = seq_lseek,
 514         .release        = single_release,
 515         .write          = cifs_lookup_cache_proc_write,
 516 };
 517
 518 static int traceSMB_proc_show(struct seq_file *m, void *v)
 519 {
 520         seq_printf(m, "%d\n", traceSMB);
 521         return 0;
 522 }
 523
 524 static int traceSMB_proc_open(struct inode *inode, struct file *file)
 525 {
 526         return single_open(file, traceSMB_proc_show, NULL);
 527 }
 528
 529 static ssize_t traceSMB_proc_write(struct file *file, const char __user *buffer,
 530                 size_t count, loff_t *ppos)
 531 {
 532         int rc;
 533
 534         rc = kstrtobool_from_user(buffer, count, &traceSMB);
 535         if (rc)
 536                 return rc;
 537
 538         return count;
 539 }
 540
 541 static const struct file_operations traceSMB_proc_fops = {
 542         .open           = traceSMB_proc_open,
 543         .read           = seq_read,
 544         .llseek         = seq_lseek,
 545         .release        = single_release,
 546         .write          = traceSMB_proc_write,
 547 };
 548
 549 static int cifs_security_flags_proc_show(struct seq_file *m, void *v)
 550 {
 551         seq_printf(m, "0x%x\n", global_secflags);
 552         return 0;
 553 }
 554
 555 static int cifs_security_flags_proc_open(struct inode *inode, struct file *file)
 556 {
 557         return single_open(file, cifs_security_flags_proc_show, NULL);
 558 }
 559
 560 /*
 561  * Ensure that if someone sets a MUST flag, that we disable all other MAY
 562  * flags except for the ones corresponding to the given MUST flag. If there are
 563  * multiple MUST flags, then try to prefer more secure ones.
 564  */
 565 static void
 566 cifs_security_flags_handle_must_flags(unsigned int *flags)
 567 {
 568         unsigned int signflags = *flags & CIFSSEC_MUST_SIGN;
 569
 570         if ((*flags & CIFSSEC_MUST_KRB5) == CIFSSEC_MUST_KRB5)
 571                 *flags = CIFSSEC_MUST_KRB5;
 572         else if ((*flags & CIFSSEC_MUST_NTLMSSP) == CIFSSEC_MUST_NTLMSSP)
 573                 *flags = CIFSSEC_MUST_NTLMSSP;
 574         else if ((*flags & CIFSSEC_MUST_NTLMV2) == CIFSSEC_MUST_NTLMV2)
 575                 *flags = CIFSSEC_MUST_NTLMV2;
 576         else if ((*flags & CIFSSEC_MUST_NTLM) == CIFSSEC_MUST_NTLM)
 577                 *flags = CIFSSEC_MUST_NTLM;
 578         else if (CIFSSEC_MUST_LANMAN &&
 579                  (*flags & CIFSSEC_MUST_LANMAN) == CIFSSEC_MUST_LANMAN)
 580                 *flags = CIFSSEC_MUST_LANMAN;
 581         else if (CIFSSEC_MUST_PLNTXT &&
 582                  (*flags & CIFSSEC_MUST_PLNTXT) == CIFSSEC_MUST_PLNTXT)
 583                 *flags = CIFSSEC_MUST_PLNTXT;
 584
 585         *flags |= signflags;
 586 }
 587
 588 static ssize_t cifs_security_flags_proc_write(struct file *file,
 589                 const char __user *buffer, size_t count, loff_t *ppos)
 590 {
 591         int rc;
 592         unsigned int flags;
 593         char flags_string[12];
 594         bool bv;
 595
 596         if ((count < 1) || (count > 11))
 597                 return -EINVAL;
 598
 599         memset(flags_string, 0, 12);
 600
 601         if (copy_from_user(flags_string, buffer, count))
 602                 return -EFAULT;
 603
 604         if (count < 3) {
 605                 /* single char or single char followed by null */
 606                 if (strtobool(flags_string, &bv) == 0) {
 607                         global_secflags = bv ? CIFSSEC_MAX : CIFSSEC_DEF;
 608                         return count;
 609                 } else if (!isdigit(flags_string[0])) {
 610                         cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 611                                         flags_string);
 612                         return -EINVAL;
 613                 }
 614         }
 615
 616         /* else we have a number */
 617         rc = kstrtouint(flags_string, 0, &flags);
 618         if (rc) {
 619                 cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 620                                 flags_string);
 621                 return rc;
 622         }
 623
 624         cifs_dbg(FYI, "sec flags 0x%x\n", flags);
 625
 626         if (flags == 0)  {
 627                 cifs_dbg(VFS, "Invalid SecurityFlags: %s\n", flags_string);
 628                 return -EINVAL;
 629         }
 630
 631         if (flags & ~CIFSSEC_MASK) {
 632                 cifs_dbg(VFS, "Unsupported security flags: 0x%x\n",
 633                          flags & ~CIFSSEC_MASK);
 634                 return -EINVAL;
 635         }
 636
 637         cifs_security_flags_handle_must_flags(&flags);
 638
 639         /* flags look ok - update the global security flags for cifs module */
 640         global_secflags = flags;
 641         if (global_secflags & CIFSSEC_MUST_SIGN) {
 642                 /* requiring signing implies signing is allowed */
 643                 global_secflags |= CIFSSEC_MAY_SIGN;
 644                 cifs_dbg(FYI, "packet signing now required\n");
 645         } else if ((global_secflags & CIFSSEC_MAY_SIGN) == 0) {
 646                 cifs_dbg(FYI, "packet signing disabled\n");
 647         }
 648         /* BB should we turn on MAY flags for other MUST options? */
 649         return count;
 650 }
 651
 652 static const struct file_operations cifs_security_flags_proc_fops = {
 653         .open           = cifs_security_flags_proc_open,
 654         .read           = seq_read,
 655         .llseek         = seq_lseek,
 656         .release        = single_release,
 657         .write          = cifs_security_flags_proc_write,
 658 };
 659 #else
 660 inline void cifs_proc_init(void)
 661 {
 662 }
 663
 664 inline void cifs_proc_clean(void)
 665 {
 666 }
 667 #endif /* PROC_FS */