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                 i++;
 156                 list_for_each(tmp2, &server->smb_ses_list) {
 157                         ses = list_entry(tmp2, struct cifs_ses,
 158                                          smb_ses_list);
 159                         if ((ses->serverDomain == NULL) ||
 160                                 (ses->serverOS == NULL) ||
 161                                 (ses->serverNOS == NULL)) {
 162                                 seq_printf(m, "\n%d) entry for %s not fully "
 163                                            "displayed\n\t", i, ses->serverName);
 164                         } else {
 165                                 seq_printf(m,
 166                                     "\n%d) Name: %s  Domain: %s Uses: %d OS:"
 167                                     " %s\n\tNOS: %s\tCapability: 0x%x\n\tSMB"
 168                                     " session status: %d\t",
 169                                 i, ses->serverName, ses->serverDomain,
 170                                 ses->ses_count, ses->serverOS, ses->serverNOS,
 171                                 ses->capabilities, ses->status);
 172                         }
 173                         seq_printf(m, "TCP status: %d\n\tLocal Users To "
 174                                    "Server: %d SecMode: 0x%x Req On Wire: %d",
 175                                    server->tcpStatus, server->srv_count,
 176                                    server->sec_mode, in_flight(server));
 177
 178 #ifdef CONFIG_CIFS_STATS2
 179                         seq_printf(m, " In Send: %d In MaxReq Wait: %d",
 180                                 atomic_read(&server->in_send),
 181                                 atomic_read(&server->num_waiters));
 182 #endif
 183
 184                         seq_puts(m, "\n\tShares:");
 185                         j = 0;
 186                         list_for_each(tmp3, &ses->tcon_list) {
 187                                 tcon = list_entry(tmp3, struct cifs_tcon,
 188                                                   tcon_list);
 189                                 ++j;
 190                                 dev_type = le32_to_cpu(tcon->fsDevInfo.DeviceType);
 191                                 seq_printf(m, "\n\t%d) %s Mounts: %d ", j,
 192                                            tcon->treeName, tcon->tc_count);
 193                                 if (tcon->nativeFileSystem) {
 194                                         seq_printf(m, "Type: %s ",
 195                                                    tcon->nativeFileSystem);
 196                                 }
 197                                 seq_printf(m, "DevInfo: 0x%x Attributes: 0x%x"
 198                                         "\n\tPathComponentMax: %d Status: %d",
 199                                         le32_to_cpu(tcon->fsDevInfo.DeviceCharacteristics),
 200                                         le32_to_cpu(tcon->fsAttrInfo.Attributes),
 201                                         le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength),
 202                                         tcon->tidStatus);
 203                                 if (dev_type == FILE_DEVICE_DISK)
 204                                         seq_puts(m, " type: DISK ");
 205                                 else if (dev_type == FILE_DEVICE_CD_ROM)
 206                                         seq_puts(m, " type: CDROM ");
 207                                 else
 208                                         seq_printf(m, " type: %d ", dev_type);
 209                                 if (server->ops->dump_share_caps)
 210                                         server->ops->dump_share_caps(m, tcon);
 211
 212                                 if (tcon->need_reconnect)
 213                                         seq_puts(m, "\tDISCONNECTED ");
 214                                 seq_putc(m, '\n');
 215                         }
 216
 217                         seq_puts(m, "\n\tMIDs:\n");
 218
 219                         spin_lock(&GlobalMid_Lock);
 220                         list_for_each(tmp3, &server->pending_mid_q) {
 221                                 mid_entry = list_entry(tmp3, struct mid_q_entry,
 222                                         qhead);
 223                                 seq_printf(m, "\tState: %d com: %d pid:"
 224                                               " %d cbdata: %p mid %llu\n",
 225                                               mid_entry->mid_state,
 226                                               le16_to_cpu(mid_entry->command),
 227                                               mid_entry->pid,
 228                                               mid_entry->callback_data,
 229                                               mid_entry->mid);
 230                         }
 231                         spin_unlock(&GlobalMid_Lock);
 232                 }
 233         }
 234         spin_unlock(&cifs_tcp_ses_lock);
 235         seq_putc(m, '\n');
 236
 237         /* BB add code to dump additional info such as TCP session info now */
 238         return 0;
 239 }
 240
 241 static int cifs_debug_data_proc_open(struct inode *inode, struct file *file)
 242 {
 243         return single_open(file, cifs_debug_data_proc_show, NULL);
 244 }
 245
 246 static const struct file_operations cifs_debug_data_proc_fops = {
 247         .open           = cifs_debug_data_proc_open,
 248         .read           = seq_read,
 249         .llseek         = seq_lseek,
 250         .release        = single_release,
 251 };
 252
 253 #ifdef CONFIG_CIFS_STATS
 254 static ssize_t cifs_stats_proc_write(struct file *file,
 255                 const char __user *buffer, size_t count, loff_t *ppos)
 256 {
 257         bool bv;
 258         int rc;
 259         struct list_head *tmp1, *tmp2, *tmp3;
 260         struct TCP_Server_Info *server;
 261         struct cifs_ses *ses;
 262         struct cifs_tcon *tcon;
 263
 264         rc = kstrtobool_from_user(buffer, count, &bv);
 265         if (rc == 0) {
 266 #ifdef CONFIG_CIFS_STATS2
 267                 atomic_set(&totBufAllocCount, 0);
 268                 atomic_set(&totSmBufAllocCount, 0);
 269 #endif /* CONFIG_CIFS_STATS2 */
 270                 spin_lock(&cifs_tcp_ses_lock);
 271                 list_for_each(tmp1, &cifs_tcp_ses_list) {
 272                         server = list_entry(tmp1, struct TCP_Server_Info,
 273                                             tcp_ses_list);
 274                         list_for_each(tmp2, &server->smb_ses_list) {
 275                                 ses = list_entry(tmp2, struct cifs_ses,
 276                                                  smb_ses_list);
 277                                 list_for_each(tmp3, &ses->tcon_list) {
 278                                         tcon = list_entry(tmp3,
 279                                                           struct cifs_tcon,
 280                                                           tcon_list);
 281                                         atomic_set(&tcon->num_smbs_sent, 0);
 282                                         if (server->ops->clear_stats)
 283                                                 server->ops->clear_stats(tcon);
 284                                 }
 285                         }
 286                 }
 287                 spin_unlock(&cifs_tcp_ses_lock);
 288         } else {
 289                 return rc;
 290         }
 291
 292         return count;
 293 }
 294
 295 static int cifs_stats_proc_show(struct seq_file *m, void *v)
 296 {
 297         int i;
 298         struct list_head *tmp1, *tmp2, *tmp3;
 299         struct TCP_Server_Info *server;
 300         struct cifs_ses *ses;
 301         struct cifs_tcon *tcon;
 302
 303         seq_printf(m,
 304                         "Resources in use\nCIFS Session: %d\n",
 305                         sesInfoAllocCount.counter);
 306         seq_printf(m, "Share (unique mount targets): %d\n",
 307                         tconInfoAllocCount.counter);
 308         seq_printf(m, "SMB Request/Response Buffer: %d Pool size: %d\n",
 309                         bufAllocCount.counter,
 310                         cifs_min_rcv + tcpSesAllocCount.counter);
 311         seq_printf(m, "SMB Small Req/Resp Buffer: %d Pool size: %d\n",
 312                         smBufAllocCount.counter, cifs_min_small);
 313 #ifdef CONFIG_CIFS_STATS2
 314         seq_printf(m, "Total Large %d Small %d Allocations\n",
 315                                 atomic_read(&totBufAllocCount),
 316                                 atomic_read(&totSmBufAllocCount));
 317 #endif /* CONFIG_CIFS_STATS2 */
 318
 319         seq_printf(m, "Operations (MIDs): %d\n", atomic_read(&midCount));
 320         seq_printf(m,
 321                 "\n%d session %d share reconnects\n",
 322                 tcpSesReconnectCount.counter, tconInfoReconnectCount.counter);
 323
 324         seq_printf(m,
 325                 "Total vfs operations: %d maximum at one time: %d\n",
 326                 GlobalCurrentXid, GlobalMaxActiveXid);
 327
 328         i = 0;
 329         spin_lock(&cifs_tcp_ses_lock);
 330         list_for_each(tmp1, &cifs_tcp_ses_list) {
 331                 server = list_entry(tmp1, struct TCP_Server_Info,
 332                                     tcp_ses_list);
 333                 list_for_each(tmp2, &server->smb_ses_list) {
 334                         ses = list_entry(tmp2, struct cifs_ses,
 335                                          smb_ses_list);
 336                         list_for_each(tmp3, &ses->tcon_list) {
 337                                 tcon = list_entry(tmp3,
 338                                                   struct cifs_tcon,
 339                                                   tcon_list);
 340                                 i++;
 341                                 seq_printf(m, "\n%d) %s", i, tcon->treeName);
 342                                 if (tcon->need_reconnect)
 343                                         seq_puts(m, "\tDISCONNECTED ");
 344                                 seq_printf(m, "\nSMBs: %d",
 345                                            atomic_read(&tcon->num_smbs_sent));
 346                                 if (server->ops->print_stats)
 347                                         server->ops->print_stats(m, tcon);
 348                         }
 349                 }
 350         }
 351         spin_unlock(&cifs_tcp_ses_lock);
 352
 353         seq_putc(m, '\n');
 354         return 0;
 355 }
 356
 357 static int cifs_stats_proc_open(struct inode *inode, struct file *file)
 358 {
 359         return single_open(file, cifs_stats_proc_show, NULL);
 360 }
 361
 362 static const struct file_operations cifs_stats_proc_fops = {
 363         .open           = cifs_stats_proc_open,
 364         .read           = seq_read,
 365         .llseek         = seq_lseek,
 366         .release        = single_release,
 367         .write          = cifs_stats_proc_write,
 368 };
 369 #endif /* STATS */
 370
 371 static struct proc_dir_entry *proc_fs_cifs;
 372 static const struct file_operations cifsFYI_proc_fops;
 373 static const struct file_operations cifs_lookup_cache_proc_fops;
 374 static const struct file_operations traceSMB_proc_fops;
 375 static const struct file_operations cifs_security_flags_proc_fops;
 376 static const struct file_operations cifs_linux_ext_proc_fops;
 377
 378 void
 379 cifs_proc_init(void)
 380 {
 381         proc_fs_cifs = proc_mkdir("fs/cifs", NULL);
 382         if (proc_fs_cifs == NULL)
 383                 return;
 384
 385         proc_create("DebugData", 0, proc_fs_cifs, &cifs_debug_data_proc_fops);
 386
 387 #ifdef CONFIG_CIFS_STATS
 388         proc_create("Stats", 0, proc_fs_cifs, &cifs_stats_proc_fops);
 389 #endif /* STATS */
 390         proc_create("cifsFYI", 0, proc_fs_cifs, &cifsFYI_proc_fops);
 391         proc_create("traceSMB", 0, proc_fs_cifs, &traceSMB_proc_fops);
 392         proc_create("LinuxExtensionsEnabled", 0, proc_fs_cifs,
 393                     &cifs_linux_ext_proc_fops);
 394         proc_create("SecurityFlags", 0, proc_fs_cifs,
 395                     &cifs_security_flags_proc_fops);
 396         proc_create("LookupCacheEnabled", 0, proc_fs_cifs,
 397                     &cifs_lookup_cache_proc_fops);
 398 }
 399
 400 void
 401 cifs_proc_clean(void)
 402 {
 403         if (proc_fs_cifs == NULL)
 404                 return;
 405
 406         remove_proc_entry("DebugData", proc_fs_cifs);
 407         remove_proc_entry("cifsFYI", proc_fs_cifs);
 408         remove_proc_entry("traceSMB", proc_fs_cifs);
 409 #ifdef CONFIG_CIFS_STATS
 410         remove_proc_entry("Stats", proc_fs_cifs);
 411 #endif
 412         remove_proc_entry("SecurityFlags", proc_fs_cifs);
 413         remove_proc_entry("LinuxExtensionsEnabled", proc_fs_cifs);
 414         remove_proc_entry("LookupCacheEnabled", proc_fs_cifs);
 415         remove_proc_entry("fs/cifs", NULL);
 416 }
 417
 418 static int cifsFYI_proc_show(struct seq_file *m, void *v)
 419 {
 420         seq_printf(m, "%d\n", cifsFYI);
 421         return 0;
 422 }
 423
 424 static int cifsFYI_proc_open(struct inode *inode, struct file *file)
 425 {
 426         return single_open(file, cifsFYI_proc_show, NULL);
 427 }
 428
 429 static ssize_t cifsFYI_proc_write(struct file *file, const char __user *buffer,
 430                 size_t count, loff_t *ppos)
 431 {
 432         char c[2] = { '\0' };
 433         bool bv;
 434         int rc;
 435
 436         rc = get_user(c[0], buffer);
 437         if (rc)
 438                 return rc;
 439         if (strtobool(c, &bv) == 0)
 440                 cifsFYI = bv;
 441         else if ((c[0] > '1') && (c[0] <= '9'))
 442                 cifsFYI = (int) (c[0] - '0'); /* see cifs_debug.h for meanings */
 443
 444         return count;
 445 }
 446
 447 static const struct file_operations cifsFYI_proc_fops = {
 448         .open           = cifsFYI_proc_open,
 449         .read           = seq_read,
 450         .llseek         = seq_lseek,
 451         .release        = single_release,
 452         .write          = cifsFYI_proc_write,
 453 };
 454
 455 static int cifs_linux_ext_proc_show(struct seq_file *m, void *v)
 456 {
 457         seq_printf(m, "%d\n", linuxExtEnabled);
 458         return 0;
 459 }
 460
 461 static int cifs_linux_ext_proc_open(struct inode *inode, struct file *file)
 462 {
 463         return single_open(file, cifs_linux_ext_proc_show, NULL);
 464 }
 465
 466 static ssize_t cifs_linux_ext_proc_write(struct file *file,
 467                 const char __user *buffer, size_t count, loff_t *ppos)
 468 {
 469         int rc;
 470
 471         rc = kstrtobool_from_user(buffer, count, &linuxExtEnabled);
 472         if (rc)
 473                 return rc;
 474
 475         return count;
 476 }
 477
 478 static const struct file_operations cifs_linux_ext_proc_fops = {
 479         .open           = cifs_linux_ext_proc_open,
 480         .read           = seq_read,
 481         .llseek         = seq_lseek,
 482         .release        = single_release,
 483         .write          = cifs_linux_ext_proc_write,
 484 };
 485
 486 static int cifs_lookup_cache_proc_show(struct seq_file *m, void *v)
 487 {
 488         seq_printf(m, "%d\n", lookupCacheEnabled);
 489         return 0;
 490 }
 491
 492 static int cifs_lookup_cache_proc_open(struct inode *inode, struct file *file)
 493 {
 494         return single_open(file, cifs_lookup_cache_proc_show, NULL);
 495 }
 496
 497 static ssize_t cifs_lookup_cache_proc_write(struct file *file,
 498                 const char __user *buffer, size_t count, loff_t *ppos)
 499 {
 500         int rc;
 501
 502         rc = kstrtobool_from_user(buffer, count, &lookupCacheEnabled);
 503         if (rc)
 504                 return rc;
 505
 506         return count;
 507 }
 508
 509 static const struct file_operations cifs_lookup_cache_proc_fops = {
 510         .open           = cifs_lookup_cache_proc_open,
 511         .read           = seq_read,
 512         .llseek         = seq_lseek,
 513         .release        = single_release,
 514         .write          = cifs_lookup_cache_proc_write,
 515 };
 516
 517 static int traceSMB_proc_show(struct seq_file *m, void *v)
 518 {
 519         seq_printf(m, "%d\n", traceSMB);
 520         return 0;
 521 }
 522
 523 static int traceSMB_proc_open(struct inode *inode, struct file *file)
 524 {
 525         return single_open(file, traceSMB_proc_show, NULL);
 526 }
 527
 528 static ssize_t traceSMB_proc_write(struct file *file, const char __user *buffer,
 529                 size_t count, loff_t *ppos)
 530 {
 531         int rc;
 532
 533         rc = kstrtobool_from_user(buffer, count, &traceSMB);
 534         if (rc)
 535                 return rc;
 536
 537         return count;
 538 }
 539
 540 static const struct file_operations traceSMB_proc_fops = {
 541         .open           = traceSMB_proc_open,
 542         .read           = seq_read,
 543         .llseek         = seq_lseek,
 544         .release        = single_release,
 545         .write          = traceSMB_proc_write,
 546 };
 547
 548 static int cifs_security_flags_proc_show(struct seq_file *m, void *v)
 549 {
 550         seq_printf(m, "0x%x\n", global_secflags);
 551         return 0;
 552 }
 553
 554 static int cifs_security_flags_proc_open(struct inode *inode, struct file *file)
 555 {
 556         return single_open(file, cifs_security_flags_proc_show, NULL);
 557 }
 558
 559 /*
 560  * Ensure that if someone sets a MUST flag, that we disable all other MAY
 561  * flags except for the ones corresponding to the given MUST flag. If there are
 562  * multiple MUST flags, then try to prefer more secure ones.
 563  */
 564 static void
 565 cifs_security_flags_handle_must_flags(unsigned int *flags)
 566 {
 567         unsigned int signflags = *flags & CIFSSEC_MUST_SIGN;
 568
 569         if ((*flags & CIFSSEC_MUST_KRB5) == CIFSSEC_MUST_KRB5)
 570                 *flags = CIFSSEC_MUST_KRB5;
 571         else if ((*flags & CIFSSEC_MUST_NTLMSSP) == CIFSSEC_MUST_NTLMSSP)
 572                 *flags = CIFSSEC_MUST_NTLMSSP;
 573         else if ((*flags & CIFSSEC_MUST_NTLMV2) == CIFSSEC_MUST_NTLMV2)
 574                 *flags = CIFSSEC_MUST_NTLMV2;
 575         else if ((*flags & CIFSSEC_MUST_NTLM) == CIFSSEC_MUST_NTLM)
 576                 *flags = CIFSSEC_MUST_NTLM;
 577         else if (CIFSSEC_MUST_LANMAN &&
 578                  (*flags & CIFSSEC_MUST_LANMAN) == CIFSSEC_MUST_LANMAN)
 579                 *flags = CIFSSEC_MUST_LANMAN;
 580         else if (CIFSSEC_MUST_PLNTXT &&
 581                  (*flags & CIFSSEC_MUST_PLNTXT) == CIFSSEC_MUST_PLNTXT)
 582                 *flags = CIFSSEC_MUST_PLNTXT;
 583
 584         *flags |= signflags;
 585 }
 586
 587 static ssize_t cifs_security_flags_proc_write(struct file *file,
 588                 const char __user *buffer, size_t count, loff_t *ppos)
 589 {
 590         int rc;
 591         unsigned int flags;
 592         char flags_string[12];
 593         bool bv;
 594
 595         if ((count < 1) || (count > 11))
 596                 return -EINVAL;
 597
 598         memset(flags_string, 0, 12);
 599
 600         if (copy_from_user(flags_string, buffer, count))
 601                 return -EFAULT;
 602
 603         if (count < 3) {
 604                 /* single char or single char followed by null */
 605                 if (strtobool(flags_string, &bv) == 0) {
 606                         global_secflags = bv ? CIFSSEC_MAX : CIFSSEC_DEF;
 607                         return count;
 608                 } else if (!isdigit(flags_string[0])) {
 609                         cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 610                                         flags_string);
 611                         return -EINVAL;
 612                 }
 613         }
 614
 615         /* else we have a number */
 616         rc = kstrtouint(flags_string, 0, &flags);
 617         if (rc) {
 618                 cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 619                                 flags_string);
 620                 return rc;
 621         }
 622
 623         cifs_dbg(FYI, "sec flags 0x%x\n", flags);
 624
 625         if (flags == 0)  {
 626                 cifs_dbg(VFS, "Invalid SecurityFlags: %s\n", flags_string);
 627                 return -EINVAL;
 628         }
 629
 630         if (flags & ~CIFSSEC_MASK) {
 631                 cifs_dbg(VFS, "Unsupported security flags: 0x%x\n",
 632                          flags & ~CIFSSEC_MASK);
 633                 return -EINVAL;
 634         }
 635
 636         cifs_security_flags_handle_must_flags(&flags);
 637
 638         /* flags look ok - update the global security flags for cifs module */
 639         global_secflags = flags;
 640         if (global_secflags & CIFSSEC_MUST_SIGN) {
 641                 /* requiring signing implies signing is allowed */
 642                 global_secflags |= CIFSSEC_MAY_SIGN;
 643                 cifs_dbg(FYI, "packet signing now required\n");
 644         } else if ((global_secflags & CIFSSEC_MAY_SIGN) == 0) {
 645                 cifs_dbg(FYI, "packet signing disabled\n");
 646         }
 647         /* BB should we turn on MAY flags for other MUST options? */
 648         return count;
 649 }
 650
 651 static const struct file_operations cifs_security_flags_proc_fops = {
 652         .open           = cifs_security_flags_proc_open,
 653         .read           = seq_read,
 654         .llseek         = seq_lseek,
 655         .release        = single_release,
 656         .write          = cifs_security_flags_proc_write,
 657 };
 658 #else
 659 inline void cifs_proc_init(void)
 660 {
 661 }
 662
 663 inline void cifs_proc_clean(void)
 664 {
 665 }
 666 #endif /* PROC_FS */