1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3 *
4 * Copyright (C) International Business Machines Corp., 2002, 2011
5 * Author(s): Steve French (sfrench@us.ibm.com),
6 * Pavel Shilovsky ((pshilovsky@samba.org) 2012
7 *
8 */
9 #include <linux/fs.h>
10 #include <linux/stat.h>
11 #include <linux/slab.h>
12 #include <linux/pagemap.h>
13 #include <asm/div64.h>
14 #include "cifsfs.h"
15 #include "cifspdu.h"
16 #include "cifsglob.h"
17 #include "cifsproto.h"
18 #include "cifs_debug.h"
19 #include "cifs_fs_sb.h"
20 #include "cifs_unicode.h"
21 #include "fscache.h"
22 #include "smb2proto.h"
23
24 int
smb2_open_file(const unsigned int xid,struct cifs_open_parms * oparms,__u32 * oplock,FILE_ALL_INFO * buf)25 smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms,
26 __u32 *oplock, FILE_ALL_INFO *buf)
27 {
28 int rc;
29 __le16 *smb2_path;
30 struct smb2_file_all_info *smb2_data = NULL;
31 __u8 smb2_oplock;
32 struct cifs_fid *fid = oparms->fid;
33 struct network_resiliency_req nr_ioctl_req;
34
35 smb2_path = cifs_convert_path_to_utf16(oparms->path, oparms->cifs_sb);
36 if (smb2_path == NULL) {
37 rc = -ENOMEM;
38 goto out;
39 }
40
41 smb2_data = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
42 GFP_KERNEL);
43 if (smb2_data == NULL) {
44 rc = -ENOMEM;
45 goto out;
46 }
47
48 oparms->desired_access |= FILE_READ_ATTRIBUTES;
49 smb2_oplock = SMB2_OPLOCK_LEVEL_BATCH;
50
51 rc = SMB2_open(xid, oparms, smb2_path, &smb2_oplock, smb2_data, NULL,
52 NULL, NULL);
53 if (rc)
54 goto out;
55
56
57 if (oparms->tcon->use_resilient) {
58 /* default timeout is 0, servers pick default (120 seconds) */
59 nr_ioctl_req.Timeout =
60 cpu_to_le32(oparms->tcon->handle_timeout);
61 nr_ioctl_req.Reserved = 0;
62 rc = SMB2_ioctl(xid, oparms->tcon, fid->persistent_fid,
63 fid->volatile_fid, FSCTL_LMR_REQUEST_RESILIENCY,
64 true /* is_fsctl */,
65 (char *)&nr_ioctl_req, sizeof(nr_ioctl_req),
66 CIFSMaxBufSize, NULL, NULL /* no return info */);
67 if (rc == -EOPNOTSUPP) {
68 cifs_dbg(VFS,
69 "resiliency not supported by server, disabling\n");
70 oparms->tcon->use_resilient = false;
71 } else if (rc)
72 cifs_dbg(FYI, "error %d setting resiliency\n", rc);
73
74 rc = 0;
75 }
76
77 if (buf) {
78 /* if open response does not have IndexNumber field - get it */
79 if (smb2_data->IndexNumber == 0) {
80 rc = SMB2_get_srv_num(xid, oparms->tcon,
81 fid->persistent_fid,
82 fid->volatile_fid,
83 &smb2_data->IndexNumber);
84 if (rc) {
85 /*
86 * let get_inode_info disable server inode
87 * numbers
88 */
89 smb2_data->IndexNumber = 0;
90 rc = 0;
91 }
92 }
93 move_smb2_info_to_cifs(buf, smb2_data);
94 }
95
96 *oplock = smb2_oplock;
97 out:
98 kfree(smb2_data);
99 kfree(smb2_path);
100 return rc;
101 }
102
103 int
smb2_unlock_range(struct cifsFileInfo * cfile,struct file_lock * flock,const unsigned int xid)104 smb2_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
105 const unsigned int xid)
106 {
107 int rc = 0, stored_rc;
108 unsigned int max_num, num = 0, max_buf;
109 struct smb2_lock_element *buf, *cur;
110 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
111 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
112 struct cifsLockInfo *li, *tmp;
113 __u64 length = 1 + flock->fl_end - flock->fl_start;
114 struct list_head tmp_llist;
115
116 INIT_LIST_HEAD(&tmp_llist);
117
118 /*
119 * Accessing maxBuf is racy with cifs_reconnect - need to store value
120 * and check it before using.
121 */
122 max_buf = tcon->ses->server->maxBuf;
123 if (max_buf < sizeof(struct smb2_lock_element))
124 return -EINVAL;
125
126 BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
127 max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
128 max_num = max_buf / sizeof(struct smb2_lock_element);
129 buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
130 if (!buf)
131 return -ENOMEM;
132
133 cur = buf;
134
135 cifs_down_write(&cinode->lock_sem);
136 list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
137 if (flock->fl_start > li->offset ||
138 (flock->fl_start + length) <
139 (li->offset + li->length))
140 continue;
141 if (current->tgid != li->pid)
142 /*
143 * flock and OFD lock are associated with an open
144 * file description, not the process.
145 */
146 if (!(flock->fl_flags & (FL_FLOCK | FL_OFDLCK)))
147 continue;
148 if (cinode->can_cache_brlcks) {
149 /*
150 * We can cache brlock requests - simply remove a lock
151 * from the file's list.
152 */
153 list_del(&li->llist);
154 cifs_del_lock_waiters(li);
155 kfree(li);
156 continue;
157 }
158 cur->Length = cpu_to_le64(li->length);
159 cur->Offset = cpu_to_le64(li->offset);
160 cur->Flags = cpu_to_le32(SMB2_LOCKFLAG_UNLOCK);
161 /*
162 * We need to save a lock here to let us add it again to the
163 * file's list if the unlock range request fails on the server.
164 */
165 list_move(&li->llist, &tmp_llist);
166 if (++num == max_num) {
167 stored_rc = smb2_lockv(xid, tcon,
168 cfile->fid.persistent_fid,
169 cfile->fid.volatile_fid,
170 current->tgid, num, buf);
171 if (stored_rc) {
172 /*
173 * We failed on the unlock range request - add
174 * all locks from the tmp list to the head of
175 * the file's list.
176 */
177 cifs_move_llist(&tmp_llist,
178 &cfile->llist->locks);
179 rc = stored_rc;
180 } else
181 /*
182 * The unlock range request succeed - free the
183 * tmp list.
184 */
185 cifs_free_llist(&tmp_llist);
186 cur = buf;
187 num = 0;
188 } else
189 cur++;
190 }
191 if (num) {
192 stored_rc = smb2_lockv(xid, tcon, cfile->fid.persistent_fid,
193 cfile->fid.volatile_fid, current->tgid,
194 num, buf);
195 if (stored_rc) {
196 cifs_move_llist(&tmp_llist, &cfile->llist->locks);
197 rc = stored_rc;
198 } else
199 cifs_free_llist(&tmp_llist);
200 }
201 up_write(&cinode->lock_sem);
202
203 kfree(buf);
204 return rc;
205 }
206
207 static int
smb2_push_mand_fdlocks(struct cifs_fid_locks * fdlocks,const unsigned int xid,struct smb2_lock_element * buf,unsigned int max_num)208 smb2_push_mand_fdlocks(struct cifs_fid_locks *fdlocks, const unsigned int xid,
209 struct smb2_lock_element *buf, unsigned int max_num)
210 {
211 int rc = 0, stored_rc;
212 struct cifsFileInfo *cfile = fdlocks->cfile;
213 struct cifsLockInfo *li;
214 unsigned int num = 0;
215 struct smb2_lock_element *cur = buf;
216 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
217
218 list_for_each_entry(li, &fdlocks->locks, llist) {
219 cur->Length = cpu_to_le64(li->length);
220 cur->Offset = cpu_to_le64(li->offset);
221 cur->Flags = cpu_to_le32(li->type |
222 SMB2_LOCKFLAG_FAIL_IMMEDIATELY);
223 if (++num == max_num) {
224 stored_rc = smb2_lockv(xid, tcon,
225 cfile->fid.persistent_fid,
226 cfile->fid.volatile_fid,
227 current->tgid, num, buf);
228 if (stored_rc)
229 rc = stored_rc;
230 cur = buf;
231 num = 0;
232 } else
233 cur++;
234 }
235 if (num) {
236 stored_rc = smb2_lockv(xid, tcon,
237 cfile->fid.persistent_fid,
238 cfile->fid.volatile_fid,
239 current->tgid, num, buf);
240 if (stored_rc)
241 rc = stored_rc;
242 }
243
244 return rc;
245 }
246
247 int
smb2_push_mandatory_locks(struct cifsFileInfo * cfile)248 smb2_push_mandatory_locks(struct cifsFileInfo *cfile)
249 {
250 int rc = 0, stored_rc;
251 unsigned int xid;
252 unsigned int max_num, max_buf;
253 struct smb2_lock_element *buf;
254 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
255 struct cifs_fid_locks *fdlocks;
256
257 xid = get_xid();
258
259 /*
260 * Accessing maxBuf is racy with cifs_reconnect - need to store value
261 * and check it for zero before using.
262 */
263 max_buf = tlink_tcon(cfile->tlink)->ses->server->maxBuf;
264 if (max_buf < sizeof(struct smb2_lock_element)) {
265 free_xid(xid);
266 return -EINVAL;
267 }
268
269 BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
270 max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
271 max_num = max_buf / sizeof(struct smb2_lock_element);
272 buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
273 if (!buf) {
274 free_xid(xid);
275 return -ENOMEM;
276 }
277
278 list_for_each_entry(fdlocks, &cinode->llist, llist) {
279 stored_rc = smb2_push_mand_fdlocks(fdlocks, xid, buf, max_num);
280 if (stored_rc)
281 rc = stored_rc;
282 }
283
284 kfree(buf);
285 free_xid(xid);
286 return rc;
287 }
288
