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1// SPDX-License-Identifier: LGPL-2.12/*3 *4 * Copyright (C) International Business Machines Corp., 2002,20085 * Author(s): Steve French (sfrench@us.ibm.com)6 *7 */8 9#include <linux/slab.h>10#include <linux/ctype.h>11#include <linux/mempool.h>12#include <linux/vmalloc.h>13#include "cifspdu.h"14#include "cifsglob.h"15#include "cifsproto.h"16#include "cifs_debug.h"17#include "smberr.h"18#include "nterr.h"19#include "cifs_unicode.h"20#include "smb2pdu.h"21#include "cifsfs.h"22#ifdef CONFIG_CIFS_DFS_UPCALL23#include "dns_resolve.h"24#include "dfs_cache.h"25#include "dfs.h"26#endif27#include "fs_context.h"28#include "cached_dir.h"29 30/* The xid serves as a useful identifier for each incoming vfs request,31 in a similar way to the mid which is useful to track each sent smb,32 and CurrentXid can also provide a running counter (although it33 will eventually wrap past zero) of the total vfs operations handled34 since the cifs fs was mounted */35 36unsigned int37_get_xid(void)38{39 unsigned int xid;40 41 spin_lock(&GlobalMid_Lock);42 GlobalTotalActiveXid++;43 44 /* keep high water mark for number of simultaneous ops in filesystem */45 if (GlobalTotalActiveXid > GlobalMaxActiveXid)46 GlobalMaxActiveXid = GlobalTotalActiveXid;47 if (GlobalTotalActiveXid > 65000)48 cifs_dbg(FYI, "warning: more than 65000 requests active\n");49 xid = GlobalCurrentXid++;50 spin_unlock(&GlobalMid_Lock);51 return xid;52}53 54void55_free_xid(unsigned int xid)56{57 spin_lock(&GlobalMid_Lock);58 /* if (GlobalTotalActiveXid == 0)59 BUG(); */60 GlobalTotalActiveXid--;61 spin_unlock(&GlobalMid_Lock);62}63 64struct cifs_ses *65sesInfoAlloc(void)66{67 struct cifs_ses *ret_buf;68 69 ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL);70 if (ret_buf) {71 atomic_inc(&sesInfoAllocCount);72 spin_lock_init(&ret_buf->ses_lock);73 ret_buf->ses_status = SES_NEW;74 ++ret_buf->ses_count;75 INIT_LIST_HEAD(&ret_buf->smb_ses_list);76 INIT_LIST_HEAD(&ret_buf->tcon_list);77 mutex_init(&ret_buf->session_mutex);78 spin_lock_init(&ret_buf->iface_lock);79 INIT_LIST_HEAD(&ret_buf->iface_list);80 spin_lock_init(&ret_buf->chan_lock);81 }82 return ret_buf;83}84 85void86sesInfoFree(struct cifs_ses *buf_to_free)87{88 struct cifs_server_iface *iface = NULL, *niface = NULL;89 90 if (buf_to_free == NULL) {91 cifs_dbg(FYI, "Null buffer passed to sesInfoFree\n");92 return;93 }94 95 unload_nls(buf_to_free->local_nls);96 atomic_dec(&sesInfoAllocCount);97 kfree(buf_to_free->serverOS);98 kfree(buf_to_free->serverDomain);99 kfree(buf_to_free->serverNOS);100 kfree_sensitive(buf_to_free->password);101 kfree_sensitive(buf_to_free->password2);102 kfree(buf_to_free->user_name);103 kfree(buf_to_free->domainName);104 kfree_sensitive(buf_to_free->auth_key.response);105 spin_lock(&buf_to_free->iface_lock);106 list_for_each_entry_safe(iface, niface, &buf_to_free->iface_list,107 iface_head)108 kref_put(&iface->refcount, release_iface);109 spin_unlock(&buf_to_free->iface_lock);110 kfree_sensitive(buf_to_free);111}112 113struct cifs_tcon *114tcon_info_alloc(bool dir_leases_enabled, enum smb3_tcon_ref_trace trace)115{116 struct cifs_tcon *ret_buf;117 static atomic_t tcon_debug_id;118 119 ret_buf = kzalloc(sizeof(*ret_buf), GFP_KERNEL);120 if (!ret_buf)121 return NULL;122 123 if (dir_leases_enabled == true) {124 ret_buf->cfids = init_cached_dirs();125 if (!ret_buf->cfids) {126 kfree(ret_buf);127 return NULL;128 }129 }130 /* else ret_buf->cfids is already set to NULL above */131 132 atomic_inc(&tconInfoAllocCount);133 ret_buf->status = TID_NEW;134 ret_buf->debug_id = atomic_inc_return(&tcon_debug_id);135 ret_buf->tc_count = 1;136 spin_lock_init(&ret_buf->tc_lock);137 INIT_LIST_HEAD(&ret_buf->openFileList);138 INIT_LIST_HEAD(&ret_buf->tcon_list);139 spin_lock_init(&ret_buf->open_file_lock);140 spin_lock_init(&ret_buf->stat_lock);141 atomic_set(&ret_buf->num_local_opens, 0);142 atomic_set(&ret_buf->num_remote_opens, 0);143 ret_buf->stats_from_time = ktime_get_real_seconds();144#ifdef CONFIG_CIFS_FSCACHE145 mutex_init(&ret_buf->fscache_lock);146#endif147 trace_smb3_tcon_ref(ret_buf->debug_id, ret_buf->tc_count, trace);148#ifdef CONFIG_CIFS_DFS_UPCALL149 INIT_LIST_HEAD(&ret_buf->dfs_ses_list);150#endif151 152 return ret_buf;153}154 155void156tconInfoFree(struct cifs_tcon *tcon, enum smb3_tcon_ref_trace trace)157{158 if (tcon == NULL) {159 cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n");160 return;161 }162 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count, trace);163 free_cached_dirs(tcon->cfids);164 atomic_dec(&tconInfoAllocCount);165 kfree(tcon->nativeFileSystem);166 kfree_sensitive(tcon->password);167 kfree(tcon->origin_fullpath);168 kfree(tcon);169}170 171struct smb_hdr *172cifs_buf_get(void)173{174 struct smb_hdr *ret_buf = NULL;175 /*176 * SMB2 header is bigger than CIFS one - no problems to clean some177 * more bytes for CIFS.178 */179 size_t buf_size = sizeof(struct smb2_hdr);180 181 /*182 * We could use negotiated size instead of max_msgsize -183 * but it may be more efficient to always alloc same size184 * albeit slightly larger than necessary and maxbuffersize185 * defaults to this and can not be bigger.186 */187 ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS);188 189 /* clear the first few header bytes */190 /* for most paths, more is cleared in header_assemble */191 memset(ret_buf, 0, buf_size + 3);192 atomic_inc(&buf_alloc_count);193#ifdef CONFIG_CIFS_STATS2194 atomic_inc(&total_buf_alloc_count);195#endif /* CONFIG_CIFS_STATS2 */196 197 return ret_buf;198}199 200void201cifs_buf_release(void *buf_to_free)202{203 if (buf_to_free == NULL) {204 /* cifs_dbg(FYI, "Null buffer passed to cifs_buf_release\n");*/205 return;206 }207 mempool_free(buf_to_free, cifs_req_poolp);208 209 atomic_dec(&buf_alloc_count);210 return;211}212 213struct smb_hdr *214cifs_small_buf_get(void)215{216 struct smb_hdr *ret_buf = NULL;217 218/* We could use negotiated size instead of max_msgsize -219 but it may be more efficient to always alloc same size220 albeit slightly larger than necessary and maxbuffersize221 defaults to this and can not be bigger */222 ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS);223 /* No need to clear memory here, cleared in header assemble */224 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/225 atomic_inc(&small_buf_alloc_count);226#ifdef CONFIG_CIFS_STATS2227 atomic_inc(&total_small_buf_alloc_count);228#endif /* CONFIG_CIFS_STATS2 */229 230 return ret_buf;231}232 233void234cifs_small_buf_release(void *buf_to_free)235{236 237 if (buf_to_free == NULL) {238 cifs_dbg(FYI, "Null buffer passed to cifs_small_buf_release\n");239 return;240 }241 mempool_free(buf_to_free, cifs_sm_req_poolp);242 243 atomic_dec(&small_buf_alloc_count);244 return;245}246 247void248free_rsp_buf(int resp_buftype, void *rsp)249{250 if (resp_buftype == CIFS_SMALL_BUFFER)251 cifs_small_buf_release(rsp);252 else if (resp_buftype == CIFS_LARGE_BUFFER)253 cifs_buf_release(rsp);254}255 256/* NB: MID can not be set if treeCon not passed in, in that257 case it is responsibility of caller to set the mid */258void259header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,260 const struct cifs_tcon *treeCon, int word_count261 /* length of fixed section (word count) in two byte units */)262{263 char *temp = (char *) buffer;264 265 memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */266 267 buffer->smb_buf_length = cpu_to_be32(268 (2 * word_count) + sizeof(struct smb_hdr) -269 4 /* RFC 1001 length field does not count */ +270 2 /* for bcc field itself */) ;271 272 buffer->Protocol[0] = 0xFF;273 buffer->Protocol[1] = 'S';274 buffer->Protocol[2] = 'M';275 buffer->Protocol[3] = 'B';276 buffer->Command = smb_command;277 buffer->Flags = 0x00; /* case sensitive */278 buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;279 buffer->Pid = cpu_to_le16((__u16)current->tgid);280 buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));281 if (treeCon) {282 buffer->Tid = treeCon->tid;283 if (treeCon->ses) {284 if (treeCon->ses->capabilities & CAP_UNICODE)285 buffer->Flags2 |= SMBFLG2_UNICODE;286 if (treeCon->ses->capabilities & CAP_STATUS32)287 buffer->Flags2 |= SMBFLG2_ERR_STATUS;288 289 /* Uid is not converted */290 buffer->Uid = treeCon->ses->Suid;291 if (treeCon->ses->server)292 buffer->Mid = get_next_mid(treeCon->ses->server);293 }294 if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)295 buffer->Flags2 |= SMBFLG2_DFS;296 if (treeCon->nocase)297 buffer->Flags |= SMBFLG_CASELESS;298 if ((treeCon->ses) && (treeCon->ses->server))299 if (treeCon->ses->server->sign)300 buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;301 }302 303/* endian conversion of flags is now done just before sending */304 buffer->WordCount = (char) word_count;305 return;306}307 308static int309check_smb_hdr(struct smb_hdr *smb)310{311 /* does it have the right SMB "signature" ? */312 if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) {313 cifs_dbg(VFS, "Bad protocol string signature header 0x%x\n",314 *(unsigned int *)smb->Protocol);315 return 1;316 }317 318 /* if it's a response then accept */319 if (smb->Flags & SMBFLG_RESPONSE)320 return 0;321 322 /* only one valid case where server sends us request */323 if (smb->Command == SMB_COM_LOCKING_ANDX)324 return 0;325 326 cifs_dbg(VFS, "Server sent request, not response. mid=%u\n",327 get_mid(smb));328 return 1;329}330 331int332checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server)333{334 struct smb_hdr *smb = (struct smb_hdr *)buf;335 __u32 rfclen = be32_to_cpu(smb->smb_buf_length);336 __u32 clc_len; /* calculated length */337 cifs_dbg(FYI, "checkSMB Length: 0x%x, smb_buf_length: 0x%x\n",338 total_read, rfclen);339 340 /* is this frame too small to even get to a BCC? */341 if (total_read < 2 + sizeof(struct smb_hdr)) {342 if ((total_read >= sizeof(struct smb_hdr) - 1)343 && (smb->Status.CifsError != 0)) {344 /* it's an error return */345 smb->WordCount = 0;346 /* some error cases do not return wct and bcc */347 return 0;348 } else if ((total_read == sizeof(struct smb_hdr) + 1) &&349 (smb->WordCount == 0)) {350 char *tmp = (char *)smb;351 /* Need to work around a bug in two servers here */352 /* First, check if the part of bcc they sent was zero */353 if (tmp[sizeof(struct smb_hdr)] == 0) {354 /* some servers return only half of bcc355 * on simple responses (wct, bcc both zero)356 * in particular have seen this on357 * ulogoffX and FindClose. This leaves358 * one byte of bcc potentially uninitialized359 */360 /* zero rest of bcc */361 tmp[sizeof(struct smb_hdr)+1] = 0;362 return 0;363 }364 cifs_dbg(VFS, "rcvd invalid byte count (bcc)\n");365 } else {366 cifs_dbg(VFS, "Length less than smb header size\n");367 }368 return -EIO;369 } else if (total_read < sizeof(*smb) + 2 * smb->WordCount) {370 cifs_dbg(VFS, "%s: can't read BCC due to invalid WordCount(%u)\n",371 __func__, smb->WordCount);372 return -EIO;373 }374 375 /* otherwise, there is enough to get to the BCC */376 if (check_smb_hdr(smb))377 return -EIO;378 clc_len = smbCalcSize(smb);379 380 if (4 + rfclen != total_read) {381 cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n",382 rfclen);383 return -EIO;384 }385 386 if (4 + rfclen != clc_len) {387 __u16 mid = get_mid(smb);388 /* check if bcc wrapped around for large read responses */389 if ((rfclen > 64 * 1024) && (rfclen > clc_len)) {390 /* check if lengths match mod 64K */391 if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF))392 return 0; /* bcc wrapped */393 }394 cifs_dbg(FYI, "Calculated size %u vs length %u mismatch for mid=%u\n",395 clc_len, 4 + rfclen, mid);396 397 if (4 + rfclen < clc_len) {398 cifs_dbg(VFS, "RFC1001 size %u smaller than SMB for mid=%u\n",399 rfclen, mid);400 return -EIO;401 } else if (rfclen > clc_len + 512) {402 /*403 * Some servers (Windows XP in particular) send more404 * data than the lengths in the SMB packet would405 * indicate on certain calls (byte range locks and406 * trans2 find first calls in particular). While the407 * client can handle such a frame by ignoring the408 * trailing data, we choose limit the amount of extra409 * data to 512 bytes.410 */411 cifs_dbg(VFS, "RFC1001 size %u more than 512 bytes larger than SMB for mid=%u\n",412 rfclen, mid);413 return -EIO;414 }415 }416 return 0;417}418 419bool420is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv)421{422 struct smb_hdr *buf = (struct smb_hdr *)buffer;423 struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;424 struct TCP_Server_Info *pserver;425 struct cifs_ses *ses;426 struct cifs_tcon *tcon;427 struct cifsInodeInfo *pCifsInode;428 struct cifsFileInfo *netfile;429 430 cifs_dbg(FYI, "Checking for oplock break or dnotify response\n");431 if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&432 (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {433 struct smb_com_transaction_change_notify_rsp *pSMBr =434 (struct smb_com_transaction_change_notify_rsp *)buf;435 struct file_notify_information *pnotify;436 __u32 data_offset = 0;437 size_t len = srv->total_read - sizeof(pSMBr->hdr.smb_buf_length);438 439 if (get_bcc(buf) > sizeof(struct file_notify_information)) {440 data_offset = le32_to_cpu(pSMBr->DataOffset);441 442 if (data_offset >443 len - sizeof(struct file_notify_information)) {444 cifs_dbg(FYI, "Invalid data_offset %u\n",445 data_offset);446 return true;447 }448 pnotify = (struct file_notify_information *)449 ((char *)&pSMBr->hdr.Protocol + data_offset);450 cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n",451 pnotify->FileName, pnotify->Action);452 /* cifs_dump_mem("Rcvd notify Data: ",buf,453 sizeof(struct smb_hdr)+60); */454 return true;455 }456 if (pSMBr->hdr.Status.CifsError) {457 cifs_dbg(FYI, "notify err 0x%x\n",458 pSMBr->hdr.Status.CifsError);459 return true;460 }461 return false;462 }463 if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)464 return false;465 if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {466 /* no sense logging error on invalid handle on oplock467 break - harmless race between close request and oplock468 break response is expected from time to time writing out469 large dirty files cached on the client */470 if ((NT_STATUS_INVALID_HANDLE) ==471 le32_to_cpu(pSMB->hdr.Status.CifsError)) {472 cifs_dbg(FYI, "Invalid handle on oplock break\n");473 return true;474 } else if (ERRbadfid ==475 le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {476 return true;477 } else {478 return false; /* on valid oplock brk we get "request" */479 }480 }481 if (pSMB->hdr.WordCount != 8)482 return false;483 484 cifs_dbg(FYI, "oplock type 0x%x level 0x%x\n",485 pSMB->LockType, pSMB->OplockLevel);486 if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))487 return false;488 489 /* If server is a channel, select the primary channel */490 pserver = SERVER_IS_CHAN(srv) ? srv->primary_server : srv;491 492 /* look up tcon based on tid & uid */493 spin_lock(&cifs_tcp_ses_lock);494 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {495 if (cifs_ses_exiting(ses))496 continue;497 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {498 if (tcon->tid != buf->Tid)499 continue;500 501 cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);502 spin_lock(&tcon->open_file_lock);503 list_for_each_entry(netfile, &tcon->openFileList, tlist) {504 if (pSMB->Fid != netfile->fid.netfid)505 continue;506 507 cifs_dbg(FYI, "file id match, oplock break\n");508 pCifsInode = CIFS_I(d_inode(netfile->dentry));509 510 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,511 &pCifsInode->flags);512 513 netfile->oplock_epoch = 0;514 netfile->oplock_level = pSMB->OplockLevel;515 netfile->oplock_break_cancelled = false;516 cifs_queue_oplock_break(netfile);517 518 spin_unlock(&tcon->open_file_lock);519 spin_unlock(&cifs_tcp_ses_lock);520 return true;521 }522 spin_unlock(&tcon->open_file_lock);523 spin_unlock(&cifs_tcp_ses_lock);524 cifs_dbg(FYI, "No matching file for oplock break\n");525 return true;526 }527 }528 spin_unlock(&cifs_tcp_ses_lock);529 cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");530 return true;531}532 533void534dump_smb(void *buf, int smb_buf_length)535{536 if (traceSMB == 0)537 return;538 539 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE, 8, 2, buf,540 smb_buf_length, true);541}542 543void544cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)545{546 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {547 struct cifs_tcon *tcon = NULL;548 549 if (cifs_sb->master_tlink)550 tcon = cifs_sb_master_tcon(cifs_sb);551 552 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;553 cifs_sb->mnt_cifs_serverino_autodisabled = true;554 cifs_dbg(VFS, "Autodisabling the use of server inode numbers on %s\n",555 tcon ? tcon->tree_name : "new server");556 cifs_dbg(VFS, "The server doesn't seem to support them properly or the files might be on different servers (DFS)\n");557 cifs_dbg(VFS, "Hardlinks will not be recognized on this mount. Consider mounting with the \"noserverino\" option to silence this message.\n");558 559 }560}561 562void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)563{564 oplock &= 0xF;565 566 if (oplock == OPLOCK_EXCLUSIVE) {567 cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG;568 cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n",569 &cinode->netfs.inode);570 } else if (oplock == OPLOCK_READ) {571 cinode->oplock = CIFS_CACHE_READ_FLG;572 cifs_dbg(FYI, "Level II Oplock granted on inode %p\n",573 &cinode->netfs.inode);574 } else575 cinode->oplock = 0;576}577 578/*579 * We wait for oplock breaks to be processed before we attempt to perform580 * writes.581 */582int cifs_get_writer(struct cifsInodeInfo *cinode)583{584 int rc;585 586start:587 rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK,588 TASK_KILLABLE);589 if (rc)590 return rc;591 592 spin_lock(&cinode->writers_lock);593 if (!cinode->writers)594 set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);595 cinode->writers++;596 /* Check to see if we have started servicing an oplock break */597 if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) {598 cinode->writers--;599 if (cinode->writers == 0) {600 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);601 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);602 }603 spin_unlock(&cinode->writers_lock);604 goto start;605 }606 spin_unlock(&cinode->writers_lock);607 return 0;608}609 610void cifs_put_writer(struct cifsInodeInfo *cinode)611{612 spin_lock(&cinode->writers_lock);613 cinode->writers--;614 if (cinode->writers == 0) {615 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);616 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);617 }618 spin_unlock(&cinode->writers_lock);619}620 621/**622 * cifs_queue_oplock_break - queue the oplock break handler for cfile623 * @cfile: The file to break the oplock on624 *625 * This function is called from the demultiplex thread when it626 * receives an oplock break for @cfile.627 *628 * Assumes the tcon->open_file_lock is held.629 * Assumes cfile->file_info_lock is NOT held.630 */631void cifs_queue_oplock_break(struct cifsFileInfo *cfile)632{633 /*634 * Bump the handle refcount now while we hold the635 * open_file_lock to enforce the validity of it for the oplock636 * break handler. The matching put is done at the end of the637 * handler.638 */639 cifsFileInfo_get(cfile);640 641 queue_work(cifsoplockd_wq, &cfile->oplock_break);642}643 644void cifs_done_oplock_break(struct cifsInodeInfo *cinode)645{646 clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);647 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK);648}649 650bool651backup_cred(struct cifs_sb_info *cifs_sb)652{653 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) {654 if (uid_eq(cifs_sb->ctx->backupuid, current_fsuid()))655 return true;656 }657 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) {658 if (in_group_p(cifs_sb->ctx->backupgid))659 return true;660 }661 662 return false;663}664 665void666cifs_del_pending_open(struct cifs_pending_open *open)667{668 spin_lock(&tlink_tcon(open->tlink)->open_file_lock);669 list_del(&open->olist);670 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock);671}672 673void674cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink,675 struct cifs_pending_open *open)676{677 memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE);678 open->oplock = CIFS_OPLOCK_NO_CHANGE;679 open->tlink = tlink;680 fid->pending_open = open;681 list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens);682}683 684void685cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink,686 struct cifs_pending_open *open)687{688 spin_lock(&tlink_tcon(tlink)->open_file_lock);689 cifs_add_pending_open_locked(fid, tlink, open);690 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock);691}692 693/*694 * Critical section which runs after acquiring deferred_lock.695 * As there is no reference count on cifs_deferred_close, pdclose696 * should not be used outside deferred_lock.697 */698bool699cifs_is_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close **pdclose)700{701 struct cifs_deferred_close *dclose;702 703 list_for_each_entry(dclose, &CIFS_I(d_inode(cfile->dentry))->deferred_closes, dlist) {704 if ((dclose->netfid == cfile->fid.netfid) &&705 (dclose->persistent_fid == cfile->fid.persistent_fid) &&706 (dclose->volatile_fid == cfile->fid.volatile_fid)) {707 *pdclose = dclose;708 return true;709 }710 }711 return false;712}713 714/*715 * Critical section which runs after acquiring deferred_lock.716 */717void718cifs_add_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close *dclose)719{720 bool is_deferred = false;721 struct cifs_deferred_close *pdclose;722 723 is_deferred = cifs_is_deferred_close(cfile, &pdclose);724 if (is_deferred) {725 kfree(dclose);726 return;727 }728 729 dclose->tlink = cfile->tlink;730 dclose->netfid = cfile->fid.netfid;731 dclose->persistent_fid = cfile->fid.persistent_fid;732 dclose->volatile_fid = cfile->fid.volatile_fid;733 list_add_tail(&dclose->dlist, &CIFS_I(d_inode(cfile->dentry))->deferred_closes);734}735 736/*737 * Critical section which runs after acquiring deferred_lock.738 */739void740cifs_del_deferred_close(struct cifsFileInfo *cfile)741{742 bool is_deferred = false;743 struct cifs_deferred_close *dclose;744 745 is_deferred = cifs_is_deferred_close(cfile, &dclose);746 if (!is_deferred)747 return;748 list_del(&dclose->dlist);749 kfree(dclose);750}751 752void753cifs_close_deferred_file(struct cifsInodeInfo *cifs_inode)754{755 struct cifsFileInfo *cfile = NULL;756 struct file_list *tmp_list, *tmp_next_list;757 LIST_HEAD(file_head);758 759 if (cifs_inode == NULL)760 return;761 762 spin_lock(&cifs_inode->open_file_lock);763 list_for_each_entry(cfile, &cifs_inode->openFileList, flist) {764 if (delayed_work_pending(&cfile->deferred)) {765 if (cancel_delayed_work(&cfile->deferred)) {766 spin_lock(&cifs_inode->deferred_lock);767 cifs_del_deferred_close(cfile);768 spin_unlock(&cifs_inode->deferred_lock);769 770 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC);771 if (tmp_list == NULL)772 break;773 tmp_list->cfile = cfile;774 list_add_tail(&tmp_list->list, &file_head);775 }776 }777 }778 spin_unlock(&cifs_inode->open_file_lock);779 780 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) {781 _cifsFileInfo_put(tmp_list->cfile, false, false);782 list_del(&tmp_list->list);783 kfree(tmp_list);784 }785}786 787void788cifs_close_all_deferred_files(struct cifs_tcon *tcon)789{790 struct cifsFileInfo *cfile;791 struct file_list *tmp_list, *tmp_next_list;792 LIST_HEAD(file_head);793 794 spin_lock(&tcon->open_file_lock);795 list_for_each_entry(cfile, &tcon->openFileList, tlist) {796 if (delayed_work_pending(&cfile->deferred)) {797 if (cancel_delayed_work(&cfile->deferred)) {798 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);799 cifs_del_deferred_close(cfile);800 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);801 802 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC);803 if (tmp_list == NULL)804 break;805 tmp_list->cfile = cfile;806 list_add_tail(&tmp_list->list, &file_head);807 }808 }809 }810 spin_unlock(&tcon->open_file_lock);811 812 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) {813 _cifsFileInfo_put(tmp_list->cfile, true, false);814 list_del(&tmp_list->list);815 kfree(tmp_list);816 }817}818void819cifs_close_deferred_file_under_dentry(struct cifs_tcon *tcon, const char *path)820{821 struct cifsFileInfo *cfile;822 struct file_list *tmp_list, *tmp_next_list;823 void *page;824 const char *full_path;825 LIST_HEAD(file_head);826 827 page = alloc_dentry_path();828 spin_lock(&tcon->open_file_lock);829 list_for_each_entry(cfile, &tcon->openFileList, tlist) {830 full_path = build_path_from_dentry(cfile->dentry, page);831 if (strstr(full_path, path)) {832 if (delayed_work_pending(&cfile->deferred)) {833 if (cancel_delayed_work(&cfile->deferred)) {834 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);835 cifs_del_deferred_close(cfile);836 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);837 838 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC);839 if (tmp_list == NULL)840 break;841 tmp_list->cfile = cfile;842 list_add_tail(&tmp_list->list, &file_head);843 }844 }845 }846 }847 spin_unlock(&tcon->open_file_lock);848 849 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) {850 _cifsFileInfo_put(tmp_list->cfile, true, false);851 list_del(&tmp_list->list);852 kfree(tmp_list);853 }854 free_dentry_path(page);855}856 857/*858 * If a dentry has been deleted, all corresponding open handles should know that859 * so that we do not defer close them.860 */861void cifs_mark_open_handles_for_deleted_file(struct inode *inode,862 const char *path)863{864 struct cifsFileInfo *cfile;865 void *page;866 const char *full_path;867 struct cifsInodeInfo *cinode = CIFS_I(inode);868 869 page = alloc_dentry_path();870 spin_lock(&cinode->open_file_lock);871 872 /*873 * note: we need to construct path from dentry and compare only if the874 * inode has any hardlinks. When number of hardlinks is 1, we can just875 * mark all open handles since they are going to be from the same file.876 */877 if (inode->i_nlink > 1) {878 list_for_each_entry(cfile, &cinode->openFileList, flist) {879 full_path = build_path_from_dentry(cfile->dentry, page);880 if (!IS_ERR(full_path) && strcmp(full_path, path) == 0)881 cfile->status_file_deleted = true;882 }883 } else {884 list_for_each_entry(cfile, &cinode->openFileList, flist)885 cfile->status_file_deleted = true;886 }887 spin_unlock(&cinode->open_file_lock);888 free_dentry_path(page);889}890 891/* parses DFS referral V3 structure892 * caller is responsible for freeing target_nodes893 * returns:894 * - on success - 0895 * - on failure - errno896 */897int898parse_dfs_referrals(struct get_dfs_referral_rsp *rsp, u32 rsp_size,899 unsigned int *num_of_nodes,900 struct dfs_info3_param **target_nodes,901 const struct nls_table *nls_codepage, int remap,902 const char *searchName, bool is_unicode)903{904 int i, rc = 0;905 char *data_end;906 struct dfs_referral_level_3 *ref;907 908 *num_of_nodes = le16_to_cpu(rsp->NumberOfReferrals);909 910 if (*num_of_nodes < 1) {911 cifs_dbg(VFS, "num_referrals: must be at least > 0, but we get num_referrals = %d\n",912 *num_of_nodes);913 rc = -EINVAL;914 goto parse_DFS_referrals_exit;915 }916 917 ref = (struct dfs_referral_level_3 *) &(rsp->referrals);918 if (ref->VersionNumber != cpu_to_le16(3)) {919 cifs_dbg(VFS, "Referrals of V%d version are not supported, should be V3\n",920 le16_to_cpu(ref->VersionNumber));921 rc = -EINVAL;922 goto parse_DFS_referrals_exit;923 }924 925 /* get the upper boundary of the resp buffer */926 data_end = (char *)rsp + rsp_size;927 928 cifs_dbg(FYI, "num_referrals: %d dfs flags: 0x%x ...\n",929 *num_of_nodes, le32_to_cpu(rsp->DFSFlags));930 931 *target_nodes = kcalloc(*num_of_nodes, sizeof(struct dfs_info3_param),932 GFP_KERNEL);933 if (*target_nodes == NULL) {934 rc = -ENOMEM;935 goto parse_DFS_referrals_exit;936 }937 938 /* collect necessary data from referrals */939 for (i = 0; i < *num_of_nodes; i++) {940 char *temp;941 int max_len;942 struct dfs_info3_param *node = (*target_nodes)+i;943 944 node->flags = le32_to_cpu(rsp->DFSFlags);945 if (is_unicode) {946 __le16 *tmp = kmalloc(strlen(searchName)*2 + 2,947 GFP_KERNEL);948 if (tmp == NULL) {949 rc = -ENOMEM;950 goto parse_DFS_referrals_exit;951 }952 cifsConvertToUTF16((__le16 *) tmp, searchName,953 PATH_MAX, nls_codepage, remap);954 node->path_consumed = cifs_utf16_bytes(tmp,955 le16_to_cpu(rsp->PathConsumed),956 nls_codepage);957 kfree(tmp);958 } else959 node->path_consumed = le16_to_cpu(rsp->PathConsumed);960 961 node->server_type = le16_to_cpu(ref->ServerType);962 node->ref_flag = le16_to_cpu(ref->ReferralEntryFlags);963 964 /* copy DfsPath */965 temp = (char *)ref + le16_to_cpu(ref->DfsPathOffset);966 max_len = data_end - temp;967 node->path_name = cifs_strndup_from_utf16(temp, max_len,968 is_unicode, nls_codepage);969 if (!node->path_name) {970 rc = -ENOMEM;971 goto parse_DFS_referrals_exit;972 }973 974 /* copy link target UNC */975 temp = (char *)ref + le16_to_cpu(ref->NetworkAddressOffset);976 max_len = data_end - temp;977 node->node_name = cifs_strndup_from_utf16(temp, max_len,978 is_unicode, nls_codepage);979 if (!node->node_name) {980 rc = -ENOMEM;981 goto parse_DFS_referrals_exit;982 }983 984 node->ttl = le32_to_cpu(ref->TimeToLive);985 986 ref++;987 }988 989parse_DFS_referrals_exit:990 if (rc) {991 free_dfs_info_array(*target_nodes, *num_of_nodes);992 *target_nodes = NULL;993 *num_of_nodes = 0;994 }995 return rc;996}997 998/**999 * cifs_alloc_hash - allocate hash and hash context together1000 * @name: The name of the crypto hash algo1001 * @sdesc: SHASH descriptor where to put the pointer to the hash TFM1002 *1003 * The caller has to make sure @sdesc is initialized to either NULL or1004 * a valid context. It can be freed via cifs_free_hash().1005 */1006int1007cifs_alloc_hash(const char *name, struct shash_desc **sdesc)1008{1009 int rc = 0;1010 struct crypto_shash *alg = NULL;1011 1012 if (*sdesc)1013 return 0;1014 1015 alg = crypto_alloc_shash(name, 0, 0);1016 if (IS_ERR(alg)) {1017 cifs_dbg(VFS, "Could not allocate shash TFM '%s'\n", name);1018 rc = PTR_ERR(alg);1019 *sdesc = NULL;1020 return rc;1021 }1022 1023 *sdesc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(alg), GFP_KERNEL);1024 if (*sdesc == NULL) {1025 cifs_dbg(VFS, "no memory left to allocate shash TFM '%s'\n", name);1026 crypto_free_shash(alg);1027 return -ENOMEM;1028 }1029 1030 (*sdesc)->tfm = alg;1031 return 0;1032}1033 1034/**1035 * cifs_free_hash - free hash and hash context together1036 * @sdesc: Where to find the pointer to the hash TFM1037 *1038 * Freeing a NULL descriptor is safe.1039 */1040void1041cifs_free_hash(struct shash_desc **sdesc)1042{1043 if (unlikely(!sdesc) || !*sdesc)1044 return;1045 1046 if ((*sdesc)->tfm) {1047 crypto_free_shash((*sdesc)->tfm);1048 (*sdesc)->tfm = NULL;1049 }1050 1051 kfree_sensitive(*sdesc);1052 *sdesc = NULL;1053}1054 1055void extract_unc_hostname(const char *unc, const char **h, size_t *len)1056{1057 const char *end;1058 1059 /* skip initial slashes */1060 while (*unc && (*unc == '\\' || *unc == '/'))1061 unc++;1062 1063 end = unc;1064 1065 while (*end && !(*end == '\\' || *end == '/'))1066 end++;1067 1068 *h = unc;1069 *len = end - unc;1070}1071 1072/**1073 * copy_path_name - copy src path to dst, possibly truncating1074 * @dst: The destination buffer1075 * @src: The source name1076 *1077 * returns number of bytes written (including trailing nul)1078 */1079int copy_path_name(char *dst, const char *src)1080{1081 int name_len;1082 1083 /*1084 * PATH_MAX includes nul, so if strlen(src) >= PATH_MAX it1085 * will truncate and strlen(dst) will be PATH_MAX-11086 */1087 name_len = strscpy(dst, src, PATH_MAX);1088 if (WARN_ON_ONCE(name_len < 0))1089 name_len = PATH_MAX-1;1090 1091 /* we count the trailing nul */1092 name_len++;1093 return name_len;1094}1095 1096struct super_cb_data {1097 void *data;1098 struct super_block *sb;1099};1100 1101static void tcon_super_cb(struct super_block *sb, void *arg)1102{1103 struct super_cb_data *sd = arg;1104 struct cifs_sb_info *cifs_sb;1105 struct cifs_tcon *t1 = sd->data, *t2;1106 1107 if (sd->sb)1108 return;1109 1110 cifs_sb = CIFS_SB(sb);1111 t2 = cifs_sb_master_tcon(cifs_sb);1112 1113 spin_lock(&t2->tc_lock);1114 if ((t1->ses == t2->ses ||1115 t1->ses->dfs_root_ses == t2->ses->dfs_root_ses) &&1116 t1->ses->server == t2->ses->server &&1117 t2->origin_fullpath &&1118 dfs_src_pathname_equal(t2->origin_fullpath, t1->origin_fullpath))1119 sd->sb = sb;1120 spin_unlock(&t2->tc_lock);1121}1122 1123static struct super_block *__cifs_get_super(void (*f)(struct super_block *, void *),1124 void *data)1125{1126 struct super_cb_data sd = {1127 .data = data,1128 .sb = NULL,1129 };1130 struct file_system_type **fs_type = (struct file_system_type *[]) {1131 &cifs_fs_type, &smb3_fs_type, NULL,1132 };1133 1134 for (; *fs_type; fs_type++) {1135 iterate_supers_type(*fs_type, f, &sd);1136 if (sd.sb) {1137 /*1138 * Grab an active reference in order to prevent automounts (DFS links)1139 * of expiring and then freeing up our cifs superblock pointer while1140 * we're doing failover.1141 */1142 cifs_sb_active(sd.sb);1143 return sd.sb;1144 }1145 }1146 pr_warn_once("%s: could not find dfs superblock\n", __func__);1147 return ERR_PTR(-EINVAL);1148}1149 1150static void __cifs_put_super(struct super_block *sb)1151{1152 if (!IS_ERR_OR_NULL(sb))1153 cifs_sb_deactive(sb);1154}1155 1156struct super_block *cifs_get_dfs_tcon_super(struct cifs_tcon *tcon)1157{1158 spin_lock(&tcon->tc_lock);1159 if (!tcon->origin_fullpath) {1160 spin_unlock(&tcon->tc_lock);1161 return ERR_PTR(-ENOENT);1162 }1163 spin_unlock(&tcon->tc_lock);1164 return __cifs_get_super(tcon_super_cb, tcon);1165}1166 1167void cifs_put_tcp_super(struct super_block *sb)1168{1169 __cifs_put_super(sb);1170}1171 1172#ifdef CONFIG_CIFS_DFS_UPCALL1173int match_target_ip(struct TCP_Server_Info *server,1174 const char *share, size_t share_len,1175 bool *result)1176{1177 int rc;1178 char *target;1179 struct sockaddr_storage ss;1180 1181 *result = false;1182 1183 target = kzalloc(share_len + 3, GFP_KERNEL);1184 if (!target)1185 return -ENOMEM;1186 1187 scnprintf(target, share_len + 3, "\\\\%.*s", (int)share_len, share);1188 1189 cifs_dbg(FYI, "%s: target name: %s\n", __func__, target + 2);1190 1191 rc = dns_resolve_server_name_to_ip(target, (struct sockaddr *)&ss, NULL);1192 kfree(target);1193 1194 if (rc < 0)1195 return rc;1196 1197 spin_lock(&server->srv_lock);1198 *result = cifs_match_ipaddr((struct sockaddr *)&server->dstaddr, (struct sockaddr *)&ss);1199 spin_unlock(&server->srv_lock);1200 cifs_dbg(FYI, "%s: ip addresses match: %u\n", __func__, *result);1201 return 0;1202}1203 1204int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix)1205{1206 int rc;1207 1208 kfree(cifs_sb->prepath);1209 cifs_sb->prepath = NULL;1210 1211 if (prefix && *prefix) {1212 cifs_sb->prepath = cifs_sanitize_prepath(prefix, GFP_ATOMIC);1213 if (IS_ERR(cifs_sb->prepath)) {1214 rc = PTR_ERR(cifs_sb->prepath);1215 cifs_sb->prepath = NULL;1216 return rc;1217 }1218 if (cifs_sb->prepath)1219 convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb));1220 }1221 1222 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;1223 return 0;1224}1225 1226/*1227 * Handle weird Windows SMB server behaviour. It responds with1228 * STATUS_OBJECT_NAME_INVALID code to SMB2 QUERY_INFO request for1229 * "\<server>\<dfsname>\<linkpath>" DFS reference, where <dfsname> contains1230 * non-ASCII unicode symbols.1231 */1232int cifs_inval_name_dfs_link_error(const unsigned int xid,1233 struct cifs_tcon *tcon,1234 struct cifs_sb_info *cifs_sb,1235 const char *full_path,1236 bool *islink)1237{1238 struct TCP_Server_Info *server = tcon->ses->server;1239 struct cifs_ses *ses = tcon->ses;1240 size_t len;1241 char *path;1242 char *ref_path;1243 1244 *islink = false;1245 1246 /*1247 * Fast path - skip check when @full_path doesn't have a prefix path to1248 * look up or tcon is not DFS.1249 */1250 if (strlen(full_path) < 2 || !cifs_sb ||1251 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) ||1252 !is_tcon_dfs(tcon))1253 return 0;1254 1255 spin_lock(&server->srv_lock);1256 if (!server->leaf_fullpath) {1257 spin_unlock(&server->srv_lock);1258 return 0;1259 }1260 spin_unlock(&server->srv_lock);1261 1262 /*1263 * Slow path - tcon is DFS and @full_path has prefix path, so attempt1264 * to get a referral to figure out whether it is an DFS link.1265 */1266 len = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1) + strlen(full_path) + 1;1267 path = kmalloc(len, GFP_KERNEL);1268 if (!path)1269 return -ENOMEM;1270 1271 scnprintf(path, len, "%s%s", tcon->tree_name, full_path);1272 ref_path = dfs_cache_canonical_path(path + 1, cifs_sb->local_nls,1273 cifs_remap(cifs_sb));1274 kfree(path);1275 1276 if (IS_ERR(ref_path)) {1277 if (PTR_ERR(ref_path) != -EINVAL)1278 return PTR_ERR(ref_path);1279 } else {1280 struct dfs_info3_param *refs = NULL;1281 int num_refs = 0;1282 1283 /*1284 * XXX: we are not using dfs_cache_find() here because we might1285 * end up filling all the DFS cache and thus potentially1286 * removing cached DFS targets that the client would eventually1287 * need during failover.1288 */1289 ses = CIFS_DFS_ROOT_SES(ses);1290 if (ses->server->ops->get_dfs_refer &&1291 !ses->server->ops->get_dfs_refer(xid, ses, ref_path, &refs,1292 &num_refs, cifs_sb->local_nls,1293 cifs_remap(cifs_sb)))1294 *islink = refs[0].server_type == DFS_TYPE_LINK;1295 free_dfs_info_array(refs, num_refs);1296 kfree(ref_path);1297 }1298 return 0;1299}1300#endif1301 1302int cifs_wait_for_server_reconnect(struct TCP_Server_Info *server, bool retry)1303{1304 int timeout = 10;1305 int rc;1306 1307 spin_lock(&server->srv_lock);1308 if (server->tcpStatus != CifsNeedReconnect) {1309 spin_unlock(&server->srv_lock);1310 return 0;1311 }1312 timeout *= server->nr_targets;1313 spin_unlock(&server->srv_lock);1314 1315 /*1316 * Give demultiplex thread up to 10 seconds to each target available for1317 * reconnect -- should be greater than cifs socket timeout which is 71318 * seconds.1319 *1320 * On "soft" mounts we wait once. Hard mounts keep retrying until1321 * process is killed or server comes back on-line.1322 */1323 do {1324 rc = wait_event_interruptible_timeout(server->response_q,1325 (server->tcpStatus != CifsNeedReconnect),1326 timeout * HZ);1327 if (rc < 0) {1328 cifs_dbg(FYI, "%s: aborting reconnect due to received signal\n",1329 __func__);1330 return -ERESTARTSYS;1331 }1332 1333 /* are we still trying to reconnect? */1334 spin_lock(&server->srv_lock);1335 if (server->tcpStatus != CifsNeedReconnect) {1336 spin_unlock(&server->srv_lock);1337 return 0;1338 }1339 spin_unlock(&server->srv_lock);1340 } while (retry);1341 1342 cifs_dbg(FYI, "%s: gave up waiting on reconnect\n", __func__);1343 return -EHOSTDOWN;1344}1345