diff options
Diffstat (limited to 'fs/smb/client/misc.c')
| -rw-r--r-- | fs/smb/client/misc.c | 1326 |
1 files changed, 1326 insertions, 0 deletions
diff --git a/fs/smb/client/misc.c b/fs/smb/client/misc.c new file mode 100644 index 000000000000..cd914be905b2 --- /dev/null +++ b/fs/smb/client/misc.c @@ -0,0 +1,1326 @@ +// SPDX-License-Identifier: LGPL-2.1 +/* + * + * Copyright (C) International Business Machines Corp., 2002,2008 + * Author(s): Steve French (sfrench@us.ibm.com) + * + */ + +#include <linux/slab.h> +#include <linux/ctype.h> +#include <linux/mempool.h> +#include <linux/vmalloc.h> +#include "cifspdu.h" +#include "cifsglob.h" +#include "cifsproto.h" +#include "cifs_debug.h" +#include "smberr.h" +#include "nterr.h" +#include "cifs_unicode.h" +#include "smb2pdu.h" +#include "cifsfs.h" +#ifdef CONFIG_CIFS_DFS_UPCALL +#include "dns_resolve.h" +#include "dfs_cache.h" +#include "dfs.h" +#endif +#include "fs_context.h" +#include "cached_dir.h" + +extern mempool_t *cifs_sm_req_poolp; +extern mempool_t *cifs_req_poolp; + +/* The xid serves as a useful identifier for each incoming vfs request, + in a similar way to the mid which is useful to track each sent smb, + and CurrentXid can also provide a running counter (although it + will eventually wrap past zero) of the total vfs operations handled + since the cifs fs was mounted */ + +unsigned int +_get_xid(void) +{ + unsigned int xid; + + spin_lock(&GlobalMid_Lock); + GlobalTotalActiveXid++; + + /* keep high water mark for number of simultaneous ops in filesystem */ + if (GlobalTotalActiveXid > GlobalMaxActiveXid) + GlobalMaxActiveXid = GlobalTotalActiveXid; + if (GlobalTotalActiveXid > 65000) + cifs_dbg(FYI, "warning: more than 65000 requests active\n"); + xid = GlobalCurrentXid++; + spin_unlock(&GlobalMid_Lock); + return xid; +} + +void +_free_xid(unsigned int xid) +{ + spin_lock(&GlobalMid_Lock); + /* if (GlobalTotalActiveXid == 0) + BUG(); */ + GlobalTotalActiveXid--; + spin_unlock(&GlobalMid_Lock); +} + +struct cifs_ses * +sesInfoAlloc(void) +{ + struct cifs_ses *ret_buf; + + ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL); + if (ret_buf) { + atomic_inc(&sesInfoAllocCount); + spin_lock_init(&ret_buf->ses_lock); + ret_buf->ses_status = SES_NEW; + ++ret_buf->ses_count; + INIT_LIST_HEAD(&ret_buf->smb_ses_list); + INIT_LIST_HEAD(&ret_buf->tcon_list); + mutex_init(&ret_buf->session_mutex); + spin_lock_init(&ret_buf->iface_lock); + INIT_LIST_HEAD(&ret_buf->iface_list); + spin_lock_init(&ret_buf->chan_lock); + } + return ret_buf; +} + +void +sesInfoFree(struct cifs_ses *buf_to_free) +{ + struct cifs_server_iface *iface = NULL, *niface = NULL; + + if (buf_to_free == NULL) { + cifs_dbg(FYI, "Null buffer passed to sesInfoFree\n"); + return; + } + + atomic_dec(&sesInfoAllocCount); + kfree(buf_to_free->serverOS); + kfree(buf_to_free->serverDomain); + kfree(buf_to_free->serverNOS); + kfree_sensitive(buf_to_free->password); + kfree(buf_to_free->user_name); + kfree(buf_to_free->domainName); + kfree_sensitive(buf_to_free->auth_key.response); + spin_lock(&buf_to_free->iface_lock); + list_for_each_entry_safe(iface, niface, &buf_to_free->iface_list, + iface_head) + kref_put(&iface->refcount, release_iface); + spin_unlock(&buf_to_free->iface_lock); + kfree_sensitive(buf_to_free); +} + +struct cifs_tcon * +tconInfoAlloc(void) +{ + struct cifs_tcon *ret_buf; + + ret_buf = kzalloc(sizeof(*ret_buf), GFP_KERNEL); + if (!ret_buf) + return NULL; + ret_buf->cfids = init_cached_dirs(); + if (!ret_buf->cfids) { + kfree(ret_buf); + return NULL; + } + + atomic_inc(&tconInfoAllocCount); + ret_buf->status = TID_NEW; + ++ret_buf->tc_count; + spin_lock_init(&ret_buf->tc_lock); + INIT_LIST_HEAD(&ret_buf->openFileList); + INIT_LIST_HEAD(&ret_buf->tcon_list); + spin_lock_init(&ret_buf->open_file_lock); + spin_lock_init(&ret_buf->stat_lock); + atomic_set(&ret_buf->num_local_opens, 0); + atomic_set(&ret_buf->num_remote_opens, 0); +#ifdef CONFIG_CIFS_DFS_UPCALL + INIT_LIST_HEAD(&ret_buf->dfs_ses_list); +#endif + + return ret_buf; +} + +void +tconInfoFree(struct cifs_tcon *tcon) +{ + if (tcon == NULL) { + cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n"); + return; + } + free_cached_dirs(tcon->cfids); + atomic_dec(&tconInfoAllocCount); + kfree(tcon->nativeFileSystem); + kfree_sensitive(tcon->password); +#ifdef CONFIG_CIFS_DFS_UPCALL + dfs_put_root_smb_sessions(&tcon->dfs_ses_list); +#endif + kfree(tcon); +} + +struct smb_hdr * +cifs_buf_get(void) +{ + struct smb_hdr *ret_buf = NULL; + /* + * SMB2 header is bigger than CIFS one - no problems to clean some + * more bytes for CIFS. + */ + size_t buf_size = sizeof(struct smb2_hdr); + + /* + * We could use negotiated size instead of max_msgsize - + * but it may be more efficient to always alloc same size + * albeit slightly larger than necessary and maxbuffersize + * defaults to this and can not be bigger. + */ + ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS); + + /* clear the first few header bytes */ + /* for most paths, more is cleared in header_assemble */ + memset(ret_buf, 0, buf_size + 3); + atomic_inc(&buf_alloc_count); +#ifdef CONFIG_CIFS_STATS2 + atomic_inc(&total_buf_alloc_count); +#endif /* CONFIG_CIFS_STATS2 */ + + return ret_buf; +} + +void +cifs_buf_release(void *buf_to_free) +{ + if (buf_to_free == NULL) { + /* cifs_dbg(FYI, "Null buffer passed to cifs_buf_release\n");*/ + return; + } + mempool_free(buf_to_free, cifs_req_poolp); + + atomic_dec(&buf_alloc_count); + return; +} + +struct smb_hdr * +cifs_small_buf_get(void) +{ + struct smb_hdr *ret_buf = NULL; + +/* We could use negotiated size instead of max_msgsize - + but it may be more efficient to always alloc same size + albeit slightly larger than necessary and maxbuffersize + defaults to this and can not be bigger */ + ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS); + /* No need to clear memory here, cleared in header assemble */ + /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/ + atomic_inc(&small_buf_alloc_count); +#ifdef CONFIG_CIFS_STATS2 + atomic_inc(&total_small_buf_alloc_count); +#endif /* CONFIG_CIFS_STATS2 */ + + return ret_buf; +} + +void +cifs_small_buf_release(void *buf_to_free) +{ + + if (buf_to_free == NULL) { + cifs_dbg(FYI, "Null buffer passed to cifs_small_buf_release\n"); + return; + } + mempool_free(buf_to_free, cifs_sm_req_poolp); + + atomic_dec(&small_buf_alloc_count); + return; +} + +void +free_rsp_buf(int resp_buftype, void *rsp) +{ + if (resp_buftype == CIFS_SMALL_BUFFER) + cifs_small_buf_release(rsp); + else if (resp_buftype == CIFS_LARGE_BUFFER) + cifs_buf_release(rsp); +} + +/* NB: MID can not be set if treeCon not passed in, in that + case it is responsbility of caller to set the mid */ +void +header_assemble(struct smb_hdr *buffer, char smb_command /* command */ , + const struct cifs_tcon *treeCon, int word_count + /* length of fixed section (word count) in two byte units */) +{ + char *temp = (char *) buffer; + + memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */ + + buffer->smb_buf_length = cpu_to_be32( + (2 * word_count) + sizeof(struct smb_hdr) - + 4 /* RFC 1001 length field does not count */ + + 2 /* for bcc field itself */) ; + + buffer->Protocol[0] = 0xFF; + buffer->Protocol[1] = 'S'; + buffer->Protocol[2] = 'M'; + buffer->Protocol[3] = 'B'; + buffer->Command = smb_command; + buffer->Flags = 0x00; /* case sensitive */ + buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES; + buffer->Pid = cpu_to_le16((__u16)current->tgid); + buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16)); + if (treeCon) { + buffer->Tid = treeCon->tid; + if (treeCon->ses) { + if (treeCon->ses->capabilities & CAP_UNICODE) + buffer->Flags2 |= SMBFLG2_UNICODE; + if (treeCon->ses->capabilities & CAP_STATUS32) + buffer->Flags2 |= SMBFLG2_ERR_STATUS; + + /* Uid is not converted */ + buffer->Uid = treeCon->ses->Suid; + if (treeCon->ses->server) + buffer->Mid = get_next_mid(treeCon->ses->server); + } + if (treeCon->Flags & SMB_SHARE_IS_IN_DFS) + buffer->Flags2 |= SMBFLG2_DFS; + if (treeCon->nocase) + buffer->Flags |= SMBFLG_CASELESS; + if ((treeCon->ses) && (treeCon->ses->server)) + if (treeCon->ses->server->sign) + buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE; + } + +/* endian conversion of flags is now done just before sending */ + buffer->WordCount = (char) word_count; + return; +} + +static int +check_smb_hdr(struct smb_hdr *smb) +{ + /* does it have the right SMB "signature" ? */ + if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) { + cifs_dbg(VFS, "Bad protocol string signature header 0x%x\n", + *(unsigned int *)smb->Protocol); + return 1; + } + + /* if it's a response then accept */ + if (smb->Flags & SMBFLG_RESPONSE) + return 0; + + /* only one valid case where server sends us request */ + if (smb->Command == SMB_COM_LOCKING_ANDX) + return 0; + + cifs_dbg(VFS, "Server sent request, not response. mid=%u\n", + get_mid(smb)); + return 1; +} + +int +checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server) +{ + struct smb_hdr *smb = (struct smb_hdr *)buf; + __u32 rfclen = be32_to_cpu(smb->smb_buf_length); + __u32 clc_len; /* calculated length */ + cifs_dbg(FYI, "checkSMB Length: 0x%x, smb_buf_length: 0x%x\n", + total_read, rfclen); + + /* is this frame too small to even get to a BCC? */ + if (total_read < 2 + sizeof(struct smb_hdr)) { + if ((total_read >= sizeof(struct smb_hdr) - 1) + && (smb->Status.CifsError != 0)) { + /* it's an error return */ + smb->WordCount = 0; + /* some error cases do not return wct and bcc */ + return 0; + } else if ((total_read == sizeof(struct smb_hdr) + 1) && + (smb->WordCount == 0)) { + char *tmp = (char *)smb; + /* Need to work around a bug in two servers here */ + /* First, check if the part of bcc they sent was zero */ + if (tmp[sizeof(struct smb_hdr)] == 0) { + /* some servers return only half of bcc + * on simple responses (wct, bcc both zero) + * in particular have seen this on + * ulogoffX and FindClose. This leaves + * one byte of bcc potentially unitialized + */ + /* zero rest of bcc */ + tmp[sizeof(struct smb_hdr)+1] = 0; + return 0; + } + cifs_dbg(VFS, "rcvd invalid byte count (bcc)\n"); + } else { + cifs_dbg(VFS, "Length less than smb header size\n"); + } + return -EIO; + } + + /* otherwise, there is enough to get to the BCC */ + if (check_smb_hdr(smb)) + return -EIO; + clc_len = smbCalcSize(smb); + + if (4 + rfclen != total_read) { + cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n", + rfclen); + return -EIO; + } + + if (4 + rfclen != clc_len) { + __u16 mid = get_mid(smb); + /* check if bcc wrapped around for large read responses */ + if ((rfclen > 64 * 1024) && (rfclen > clc_len)) { + /* check if lengths match mod 64K */ + if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF)) + return 0; /* bcc wrapped */ + } + cifs_dbg(FYI, "Calculated size %u vs length %u mismatch for mid=%u\n", + clc_len, 4 + rfclen, mid); + + if (4 + rfclen < clc_len) { + cifs_dbg(VFS, "RFC1001 size %u smaller than SMB for mid=%u\n", + rfclen, mid); + return -EIO; + } else if (rfclen > clc_len + 512) { + /* + * Some servers (Windows XP in particular) send more + * data than the lengths in the SMB packet would + * indicate on certain calls (byte range locks and + * trans2 find first calls in particular). While the + * client can handle such a frame by ignoring the + * trailing data, we choose limit the amount of extra + * data to 512 bytes. + */ + cifs_dbg(VFS, "RFC1001 size %u more than 512 bytes larger than SMB for mid=%u\n", + rfclen, mid); + return -EIO; + } + } + return 0; +} + +bool +is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv) +{ + struct smb_hdr *buf = (struct smb_hdr *)buffer; + struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf; + struct TCP_Server_Info *pserver; + struct cifs_ses *ses; + struct cifs_tcon *tcon; + struct cifsInodeInfo *pCifsInode; + struct cifsFileInfo *netfile; + + cifs_dbg(FYI, "Checking for oplock break or dnotify response\n"); + if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) && + (pSMB->hdr.Flags & SMBFLG_RESPONSE)) { + struct smb_com_transaction_change_notify_rsp *pSMBr = + (struct smb_com_transaction_change_notify_rsp *)buf; + struct file_notify_information *pnotify; + __u32 data_offset = 0; + size_t len = srv->total_read - sizeof(pSMBr->hdr.smb_buf_length); + + if (get_bcc(buf) > sizeof(struct file_notify_information)) { + data_offset = le32_to_cpu(pSMBr->DataOffset); + + if (data_offset > + len - sizeof(struct file_notify_information)) { + cifs_dbg(FYI, "Invalid data_offset %u\n", + data_offset); + return true; + } + pnotify = (struct file_notify_information *) + ((char *)&pSMBr->hdr.Protocol + data_offset); + cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n", + pnotify->FileName, pnotify->Action); + /* cifs_dump_mem("Rcvd notify Data: ",buf, + sizeof(struct smb_hdr)+60); */ + return true; + } + if (pSMBr->hdr.Status.CifsError) { + cifs_dbg(FYI, "notify err 0x%x\n", + pSMBr->hdr.Status.CifsError); + return true; + } + return false; + } + if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX) + return false; + if (pSMB->hdr.Flags & SMBFLG_RESPONSE) { + /* no sense logging error on invalid handle on oplock + break - harmless race between close request and oplock + break response is expected from time to time writing out + large dirty files cached on the client */ + if ((NT_STATUS_INVALID_HANDLE) == + le32_to_cpu(pSMB->hdr.Status.CifsError)) { + cifs_dbg(FYI, "Invalid handle on oplock break\n"); + return true; + } else if (ERRbadfid == + le16_to_cpu(pSMB->hdr.Status.DosError.Error)) { + return true; + } else { + return false; /* on valid oplock brk we get "request" */ + } + } + if (pSMB->hdr.WordCount != 8) + return false; + + cifs_dbg(FYI, "oplock type 0x%x level 0x%x\n", + pSMB->LockType, pSMB->OplockLevel); + if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)) + return false; + + /* If server is a channel, select the primary channel */ + pserver = CIFS_SERVER_IS_CHAN(srv) ? srv->primary_server : srv; + + /* look up tcon based on tid & uid */ + spin_lock(&cifs_tcp_ses_lock); + list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) { + list_for_each_entry(tcon, &ses->tcon_list, tcon_list) { + if (tcon->tid != buf->Tid) + continue; + + cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks); + spin_lock(&tcon->open_file_lock); + list_for_each_entry(netfile, &tcon->openFileList, tlist) { + if (pSMB->Fid != netfile->fid.netfid) + continue; + + cifs_dbg(FYI, "file id match, oplock break\n"); + pCifsInode = CIFS_I(d_inode(netfile->dentry)); + + set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, + &pCifsInode->flags); + + netfile->oplock_epoch = 0; + netfile->oplock_level = pSMB->OplockLevel; + netfile->oplock_break_cancelled = false; + cifs_queue_oplock_break(netfile); + + spin_unlock(&tcon->open_file_lock); + spin_unlock(&cifs_tcp_ses_lock); + return true; + } + spin_unlock(&tcon->open_file_lock); + spin_unlock(&cifs_tcp_ses_lock); + cifs_dbg(FYI, "No matching file for oplock break\n"); + return true; + } + } + spin_unlock(&cifs_tcp_ses_lock); + cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n"); + return true; +} + +void +dump_smb(void *buf, int smb_buf_length) +{ + if (traceSMB == 0) + return; + + print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE, 8, 2, buf, + smb_buf_length, true); +} + +void +cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb) +{ + if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) { + struct cifs_tcon *tcon = NULL; + + if (cifs_sb->master_tlink) + tcon = cifs_sb_master_tcon(cifs_sb); + + cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM; + cifs_sb->mnt_cifs_serverino_autodisabled = true; + cifs_dbg(VFS, "Autodisabling the use of server inode numbers on %s\n", + tcon ? tcon->tree_name : "new server"); + cifs_dbg(VFS, "The server doesn't seem to support them properly or the files might be on different servers (DFS)\n"); + cifs_dbg(VFS, "Hardlinks will not be recognized on this mount. Consider mounting with the \"noserverino\" option to silence this message.\n"); + + } +} + +void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock) +{ + oplock &= 0xF; + + if (oplock == OPLOCK_EXCLUSIVE) { + cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG; + cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n", + &cinode->netfs.inode); + } else if (oplock == OPLOCK_READ) { + cinode->oplock = CIFS_CACHE_READ_FLG; + cifs_dbg(FYI, "Level II Oplock granted on inode %p\n", + &cinode->netfs.inode); + } else + cinode->oplock = 0; +} + +/* + * We wait for oplock breaks to be processed before we attempt to perform + * writes. + */ +int cifs_get_writer(struct cifsInodeInfo *cinode) +{ + int rc; + +start: + rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK, + TASK_KILLABLE); + if (rc) + return rc; + + spin_lock(&cinode->writers_lock); + if (!cinode->writers) + set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); + cinode->writers++; + /* Check to see if we have started servicing an oplock break */ + if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) { + cinode->writers--; + if (cinode->writers == 0) { + clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); + wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS); + } + spin_unlock(&cinode->writers_lock); + goto start; + } + spin_unlock(&cinode->writers_lock); + return 0; +} + +void cifs_put_writer(struct cifsInodeInfo *cinode) +{ + spin_lock(&cinode->writers_lock); + cinode->writers--; + if (cinode->writers == 0) { + clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); + wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS); + } + spin_unlock(&cinode->writers_lock); +} + +/** + * cifs_queue_oplock_break - queue the oplock break handler for cfile + * @cfile: The file to break the oplock on + * + * This function is called from the demultiplex thread when it + * receives an oplock break for @cfile. + * + * Assumes the tcon->open_file_lock is held. + * Assumes cfile->file_info_lock is NOT held. + */ +void cifs_queue_oplock_break(struct cifsFileInfo *cfile) +{ + /* + * Bump the handle refcount now while we hold the + * open_file_lock to enforce the validity of it for the oplock + * break handler. The matching put is done at the end of the + * handler. + */ + cifsFileInfo_get(cfile); + + queue_work(cifsoplockd_wq, &cfile->oplock_break); +} + +void cifs_done_oplock_break(struct cifsInodeInfo *cinode) +{ + clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags); + wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK); +} + +bool +backup_cred(struct cifs_sb_info *cifs_sb) +{ + if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) { + if (uid_eq(cifs_sb->ctx->backupuid, current_fsuid())) + return true; + } + if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) { + if (in_group_p(cifs_sb->ctx->backupgid)) + return true; + } + + return false; +} + +void +cifs_del_pending_open(struct cifs_pending_open *open) +{ + spin_lock(&tlink_tcon(open->tlink)->open_file_lock); + list_del(&open->olist); + spin_unlock(&tlink_tcon(open->tlink)->open_file_lock); +} + +void +cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink, + struct cifs_pending_open *open) +{ + memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE); + open->oplock = CIFS_OPLOCK_NO_CHANGE; + open->tlink = tlink; + fid->pending_open = open; + list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens); +} + +void +cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink, + struct cifs_pending_open *open) +{ + spin_lock(&tlink_tcon(tlink)->open_file_lock); + cifs_add_pending_open_locked(fid, tlink, open); + spin_unlock(&tlink_tcon(open->tlink)->open_file_lock); +} + +/* + * Critical section which runs after acquiring deferred_lock. + * As there is no reference count on cifs_deferred_close, pdclose + * should not be used outside deferred_lock. + */ +bool +cifs_is_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close **pdclose) +{ + struct cifs_deferred_close *dclose; + + list_for_each_entry(dclose, &CIFS_I(d_inode(cfile->dentry))->deferred_closes, dlist) { + if ((dclose->netfid == cfile->fid.netfid) && + (dclose->persistent_fid == cfile->fid.persistent_fid) && + (dclose->volatile_fid == cfile->fid.volatile_fid)) { + *pdclose = dclose; + return true; + } + } + return false; +} + +/* + * Critical section which runs after acquiring deferred_lock. + */ +void +cifs_add_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close *dclose) +{ + bool is_deferred = false; + struct cifs_deferred_close *pdclose; + + is_deferred = cifs_is_deferred_close(cfile, &pdclose); + if (is_deferred) { + kfree(dclose); + return; + } + + dclose->tlink = cfile->tlink; + dclose->netfid = cfile->fid.netfid; + dclose->persistent_fid = cfile->fid.persistent_fid; + dclose->volatile_fid = cfile->fid.volatile_fid; + list_add_tail(&dclose->dlist, &CIFS_I(d_inode(cfile->dentry))->deferred_closes); +} + +/* + * Critical section which runs after acquiring deferred_lock. + */ +void +cifs_del_deferred_close(struct cifsFileInfo *cfile) +{ + bool is_deferred = false; + struct cifs_deferred_close *dclose; + + is_deferred = cifs_is_deferred_close(cfile, &dclose); + if (!is_deferred) + return; + list_del(&dclose->dlist); + kfree(dclose); +} + +void +cifs_close_deferred_file(struct cifsInodeInfo *cifs_inode) +{ + struct cifsFileInfo *cfile = NULL; + struct file_list *tmp_list, *tmp_next_list; + struct list_head file_head; + + if (cifs_inode == NULL) + return; + + INIT_LIST_HEAD(&file_head); + spin_lock(&cifs_inode->open_file_lock); + list_for_each_entry(cfile, &cifs_inode->openFileList, flist) { + if (delayed_work_pending(&cfile->deferred)) { + if (cancel_delayed_work(&cfile->deferred)) { + spin_lock(&cifs_inode->deferred_lock); + cifs_del_deferred_close(cfile); + spin_unlock(&cifs_inode->deferred_lock); + + tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); + if (tmp_list == NULL) + break; + tmp_list->cfile = cfile; + list_add_tail(&tmp_list->list, &file_head); + } + } + } + spin_unlock(&cifs_inode->open_file_lock); + + list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { + _cifsFileInfo_put(tmp_list->cfile, false, false); + list_del(&tmp_list->list); + kfree(tmp_list); + } +} + +void +cifs_close_all_deferred_files(struct cifs_tcon *tcon) +{ + struct cifsFileInfo *cfile; + struct file_list *tmp_list, *tmp_next_list; + struct list_head file_head; + + INIT_LIST_HEAD(&file_head); + spin_lock(&tcon->open_file_lock); + list_for_each_entry(cfile, &tcon->openFileList, tlist) { + if (delayed_work_pending(&cfile->deferred)) { + if (cancel_delayed_work(&cfile->deferred)) { + spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); + cifs_del_deferred_close(cfile); + spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); + + tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); + if (tmp_list == NULL) + break; + tmp_list->cfile = cfile; + list_add_tail(&tmp_list->list, &file_head); + } + } + } + spin_unlock(&tcon->open_file_lock); + + list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { + _cifsFileInfo_put(tmp_list->cfile, true, false); + list_del(&tmp_list->list); + kfree(tmp_list); + } +} +void +cifs_close_deferred_file_under_dentry(struct cifs_tcon *tcon, const char *path) +{ + struct cifsFileInfo *cfile; + struct file_list *tmp_list, *tmp_next_list; + struct list_head file_head; + void *page; + const char *full_path; + + INIT_LIST_HEAD(&file_head); + page = alloc_dentry_path(); + spin_lock(&tcon->open_file_lock); + list_for_each_entry(cfile, &tcon->openFileList, tlist) { + full_path = build_path_from_dentry(cfile->dentry, page); + if (strstr(full_path, path)) { + if (delayed_work_pending(&cfile->deferred)) { + if (cancel_delayed_work(&cfile->deferred)) { + spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); + cifs_del_deferred_close(cfile); + spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); + + tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); + if (tmp_list == NULL) + break; + tmp_list->cfile = cfile; + list_add_tail(&tmp_list->list, &file_head); + } + } + } + } + spin_unlock(&tcon->open_file_lock); + + list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { + _cifsFileInfo_put(tmp_list->cfile, true, false); + list_del(&tmp_list->list); + kfree(tmp_list); + } + free_dentry_path(page); +} + +/* parses DFS referral V3 structure + * caller is responsible for freeing target_nodes + * returns: + * - on success - 0 + * - on failure - errno + */ +int +parse_dfs_referrals(struct get_dfs_referral_rsp *rsp, u32 rsp_size, + unsigned int *num_of_nodes, + struct dfs_info3_param **target_nodes, + const struct nls_table *nls_codepage, int remap, + const char *searchName, bool is_unicode) +{ + int i, rc = 0; + char *data_end; + struct dfs_referral_level_3 *ref; + + *num_of_nodes = le16_to_cpu(rsp->NumberOfReferrals); + + if (*num_of_nodes < 1) { + cifs_dbg(VFS, "num_referrals: must be at least > 0, but we get num_referrals = %d\n", + *num_of_nodes); + rc = -EINVAL; + goto parse_DFS_referrals_exit; + } + + ref = (struct dfs_referral_level_3 *) &(rsp->referrals); + if (ref->VersionNumber != cpu_to_le16(3)) { + cifs_dbg(VFS, "Referrals of V%d version are not supported, should be V3\n", + le16_to_cpu(ref->VersionNumber)); + rc = -EINVAL; + goto parse_DFS_referrals_exit; + } + + /* get the upper boundary of the resp buffer */ + data_end = (char *)rsp + rsp_size; + + cifs_dbg(FYI, "num_referrals: %d dfs flags: 0x%x ...\n", + *num_of_nodes, le32_to_cpu(rsp->DFSFlags)); + + *target_nodes = kcalloc(*num_of_nodes, sizeof(struct dfs_info3_param), + GFP_KERNEL); + if (*target_nodes == NULL) { + rc = -ENOMEM; + goto parse_DFS_referrals_exit; + } + + /* collect necessary data from referrals */ + for (i = 0; i < *num_of_nodes; i++) { + char *temp; + int max_len; + struct dfs_info3_param *node = (*target_nodes)+i; + + node->flags = le32_to_cpu(rsp->DFSFlags); + if (is_unicode) { + __le16 *tmp = kmalloc(strlen(searchName)*2 + 2, + GFP_KERNEL); + if (tmp == NULL) { + rc = -ENOMEM; + goto parse_DFS_referrals_exit; + } + cifsConvertToUTF16((__le16 *) tmp, searchName, + PATH_MAX, nls_codepage, remap); + node->path_consumed = cifs_utf16_bytes(tmp, + le16_to_cpu(rsp->PathConsumed), + nls_codepage); + kfree(tmp); + } else + node->path_consumed = le16_to_cpu(rsp->PathConsumed); + + node->server_type = le16_to_cpu(ref->ServerType); + node->ref_flag = le16_to_cpu(ref->ReferralEntryFlags); + + /* copy DfsPath */ + temp = (char *)ref + le16_to_cpu(ref->DfsPathOffset); + max_len = data_end - temp; + node->path_name = cifs_strndup_from_utf16(temp, max_len, + is_unicode, nls_codepage); + if (!node->path_name) { + rc = -ENOMEM; + goto parse_DFS_referrals_exit; + } + + /* copy link target UNC */ + temp = (char *)ref + le16_to_cpu(ref->NetworkAddressOffset); + max_len = data_end - temp; + node->node_name = cifs_strndup_from_utf16(temp, max_len, + is_unicode, nls_codepage); + if (!node->node_name) { + rc = -ENOMEM; + goto parse_DFS_referrals_exit; + } + + node->ttl = le32_to_cpu(ref->TimeToLive); + + ref++; + } + +parse_DFS_referrals_exit: + if (rc) { + free_dfs_info_array(*target_nodes, *num_of_nodes); + *target_nodes = NULL; + *num_of_nodes = 0; + } + return rc; +} + +struct cifs_aio_ctx * +cifs_aio_ctx_alloc(void) +{ + struct cifs_aio_ctx *ctx; + + /* + * Must use kzalloc to initialize ctx->bv to NULL and ctx->direct_io + * to false so that we know when we have to unreference pages within + * cifs_aio_ctx_release() + */ + ctx = kzalloc(sizeof(struct cifs_aio_ctx), GFP_KERNEL); + if (!ctx) + return NULL; + + INIT_LIST_HEAD(&ctx->list); + mutex_init(&ctx->aio_mutex); + init_completion(&ctx->done); + kref_init(&ctx->refcount); + return ctx; +} + +void +cifs_aio_ctx_release(struct kref *refcount) +{ + struct cifs_aio_ctx *ctx = container_of(refcount, + struct cifs_aio_ctx, refcount); + + cifsFileInfo_put(ctx->cfile); + + /* + * ctx->bv is only set if setup_aio_ctx_iter() was call successfuly + * which means that iov_iter_extract_pages() was a success and thus + * that we may have references or pins on pages that we need to + * release. + */ + if (ctx->bv) { + if (ctx->should_dirty || ctx->bv_need_unpin) { + unsigned int i; + + for (i = 0; i < ctx->nr_pinned_pages; i++) { + struct page *page = ctx->bv[i].bv_page; + + if (ctx->should_dirty) + set_page_dirty(page); + if (ctx->bv_need_unpin) + unpin_user_page(page); + } + } + kvfree(ctx->bv); + } + + kfree(ctx); +} + +/** + * cifs_alloc_hash - allocate hash and hash context together + * @name: The name of the crypto hash algo + * @sdesc: SHASH descriptor where to put the pointer to the hash TFM + * + * The caller has to make sure @sdesc is initialized to either NULL or + * a valid context. It can be freed via cifs_free_hash(). + */ +int +cifs_alloc_hash(const char *name, struct shash_desc **sdesc) +{ + int rc = 0; + struct crypto_shash *alg = NULL; + + if (*sdesc) + return 0; + + alg = crypto_alloc_shash(name, 0, 0); + if (IS_ERR(alg)) { + cifs_dbg(VFS, "Could not allocate shash TFM '%s'\n", name); + rc = PTR_ERR(alg); + *sdesc = NULL; + return rc; + } + + *sdesc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(alg), GFP_KERNEL); + if (*sdesc == NULL) { + cifs_dbg(VFS, "no memory left to allocate shash TFM '%s'\n", name); + crypto_free_shash(alg); + return -ENOMEM; + } + + (*sdesc)->tfm = alg; + return 0; +} + +/** + * cifs_free_hash - free hash and hash context together + * @sdesc: Where to find the pointer to the hash TFM + * + * Freeing a NULL descriptor is safe. + */ +void +cifs_free_hash(struct shash_desc **sdesc) +{ + if (unlikely(!sdesc) || !*sdesc) + return; + + if ((*sdesc)->tfm) { + crypto_free_shash((*sdesc)->tfm); + (*sdesc)->tfm = NULL; + } + + kfree_sensitive(*sdesc); + *sdesc = NULL; +} + +void extract_unc_hostname(const char *unc, const char **h, size_t *len) +{ + const char *end; + + /* skip initial slashes */ + while (*unc && (*unc == '\\' || *unc == '/')) + unc++; + + end = unc; + + while (*end && !(*end == '\\' || *end == '/')) + end++; + + *h = unc; + *len = end - unc; +} + +/** + * copy_path_name - copy src path to dst, possibly truncating + * @dst: The destination buffer + * @src: The source name + * + * returns number of bytes written (including trailing nul) + */ +int copy_path_name(char *dst, const char *src) +{ + int name_len; + + /* + * PATH_MAX includes nul, so if strlen(src) >= PATH_MAX it + * will truncate and strlen(dst) will be PATH_MAX-1 + */ + name_len = strscpy(dst, src, PATH_MAX); + if (WARN_ON_ONCE(name_len < 0)) + name_len = PATH_MAX-1; + + /* we count the trailing nul */ + name_len++; + return name_len; +} + +struct super_cb_data { + void *data; + struct super_block *sb; +}; + +static void tcp_super_cb(struct super_block *sb, void *arg) +{ + struct super_cb_data *sd = arg; + struct TCP_Server_Info *server = sd->data; + struct cifs_sb_info *cifs_sb; + struct cifs_tcon *tcon; + + if (sd->sb) + return; + + cifs_sb = CIFS_SB(sb); + tcon = cifs_sb_master_tcon(cifs_sb); + if (tcon->ses->server == server) + sd->sb = sb; +} + +static struct super_block *__cifs_get_super(void (*f)(struct super_block *, void *), + void *data) +{ + struct super_cb_data sd = { + .data = data, + .sb = NULL, + }; + struct file_system_type **fs_type = (struct file_system_type *[]) { + &cifs_fs_type, &smb3_fs_type, NULL, + }; + + for (; *fs_type; fs_type++) { + iterate_supers_type(*fs_type, f, &sd); + if (sd.sb) { + /* + * Grab an active reference in order to prevent automounts (DFS links) + * of expiring and then freeing up our cifs superblock pointer while + * we're doing failover. + */ + cifs_sb_active(sd.sb); + return sd.sb; + } + } + return ERR_PTR(-EINVAL); +} + +static void __cifs_put_super(struct super_block *sb) +{ + if (!IS_ERR_OR_NULL(sb)) + cifs_sb_deactive(sb); +} + +struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server) +{ + return __cifs_get_super(tcp_super_cb, server); +} + +void cifs_put_tcp_super(struct super_block *sb) +{ + __cifs_put_super(sb); +} + +#ifdef CONFIG_CIFS_DFS_UPCALL +int match_target_ip(struct TCP_Server_Info *server, + const char *share, size_t share_len, + bool *result) +{ + int rc; + char *target; + struct sockaddr_storage ss; + + *result = false; + + target = kzalloc(share_len + 3, GFP_KERNEL); + if (!target) + return -ENOMEM; + + scnprintf(target, share_len + 3, "\\\\%.*s", (int)share_len, share); + + cifs_dbg(FYI, "%s: target name: %s\n", __func__, target + 2); + + rc = dns_resolve_server_name_to_ip(target, (struct sockaddr *)&ss, NULL); + kfree(target); + + if (rc < 0) + return rc; + + spin_lock(&server->srv_lock); + *result = cifs_match_ipaddr((struct sockaddr *)&server->dstaddr, (struct sockaddr *)&ss); + spin_unlock(&server->srv_lock); + cifs_dbg(FYI, "%s: ip addresses match: %u\n", __func__, *result); + return 0; +} + +int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix) +{ + kfree(cifs_sb->prepath); + + if (prefix && *prefix) { + cifs_sb->prepath = cifs_sanitize_prepath(prefix, GFP_ATOMIC); + if (!cifs_sb->prepath) + return -ENOMEM; + + convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb)); + } else + cifs_sb->prepath = NULL; + + cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; + return 0; +} + +/* + * Handle weird Windows SMB server behaviour. It responds with + * STATUS_OBJECT_NAME_INVALID code to SMB2 QUERY_INFO request for + * "\<server>\<dfsname>\<linkpath>" DFS reference, where <dfsname> contains + * non-ASCII unicode symbols. + */ +int cifs_inval_name_dfs_link_error(const unsigned int xid, + struct cifs_tcon *tcon, + struct cifs_sb_info *cifs_sb, + const char *full_path, + bool *islink) +{ + struct cifs_ses *ses = tcon->ses; + size_t len; + char *path; + char *ref_path; + + *islink = false; + + /* + * Fast path - skip check when @full_path doesn't have a prefix path to + * look up or tcon is not DFS. + */ + if (strlen(full_path) < 2 || !cifs_sb || + (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) || + !is_tcon_dfs(tcon) || !ses->server->origin_fullpath) + return 0; + + /* + * Slow path - tcon is DFS and @full_path has prefix path, so attempt + * to get a referral to figure out whether it is an DFS link. + */ + len = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1) + strlen(full_path) + 1; + path = kmalloc(len, GFP_KERNEL); + if (!path) + return -ENOMEM; + + scnprintf(path, len, "%s%s", tcon->tree_name, full_path); + ref_path = dfs_cache_canonical_path(path + 1, cifs_sb->local_nls, + cifs_remap(cifs_sb)); + kfree(path); + + if (IS_ERR(ref_path)) { + if (PTR_ERR(ref_path) != -EINVAL) + return PTR_ERR(ref_path); + } else { + struct dfs_info3_param *refs = NULL; + int num_refs = 0; + + /* + * XXX: we are not using dfs_cache_find() here because we might + * end filling all the DFS cache and thus potentially + * removing cached DFS targets that the client would eventually + * need during failover. + */ + ses = CIFS_DFS_ROOT_SES(ses); + if (ses->server->ops->get_dfs_refer && + !ses->server->ops->get_dfs_refer(xid, ses, ref_path, &refs, + &num_refs, cifs_sb->local_nls, + cifs_remap(cifs_sb))) + *islink = refs[0].server_type == DFS_TYPE_LINK; + free_dfs_info_array(refs, num_refs); + kfree(ref_path); + } + return 0; +} +#endif + +int cifs_wait_for_server_reconnect(struct TCP_Server_Info *server, bool retry) +{ + int timeout = 10; + int rc; + + spin_lock(&server->srv_lock); + if (server->tcpStatus != CifsNeedReconnect) { + spin_unlock(&server->srv_lock); + return 0; + } + timeout *= server->nr_targets; + spin_unlock(&server->srv_lock); + + /* + * Give demultiplex thread up to 10 seconds to each target available for + * reconnect -- should be greater than cifs socket timeout which is 7 + * seconds. + * + * On "soft" mounts we wait once. Hard mounts keep retrying until + * process is killed or server comes back on-line. + */ + do { + rc = wait_event_interruptible_timeout(server->response_q, + (server->tcpStatus != CifsNeedReconnect), + timeout * HZ); + if (rc < 0) { + cifs_dbg(FYI, "%s: aborting reconnect due to received signal\n", + __func__); + return -ERESTARTSYS; + } + + /* are we still trying to reconnect? */ + spin_lock(&server->srv_lock); + if (server->tcpStatus != CifsNeedReconnect) { + spin_unlock(&server->srv_lock); + return 0; + } + spin_unlock(&server->srv_lock); + } while (retry); + + cifs_dbg(FYI, "%s: gave up waiting on reconnect\n", __func__); + return -EHOSTDOWN; +} |