Loading...
Note: File does not exist in v5.4.
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/filelock.h>
11#include <linux/stat.h>
12#include <linux/slab.h>
13#include <linux/pagemap.h>
14#include <asm/div64.h>
15#include "cifsfs.h"
16#include "cifspdu.h"
17#include "cifsglob.h"
18#include "cifsproto.h"
19#include "cifs_debug.h"
20#include "cifs_fs_sb.h"
21#include "cifs_unicode.h"
22#include "fscache.h"
23#include "smb2proto.h"
24#include "../common/smb2status.h"
25
26static struct smb2_symlink_err_rsp *symlink_data(const struct kvec *iov)
27{
28 struct smb2_err_rsp *err = iov->iov_base;
29 struct smb2_symlink_err_rsp *sym = ERR_PTR(-EINVAL);
30 u32 len;
31
32 if (err->ErrorContextCount) {
33 struct smb2_error_context_rsp *p, *end;
34
35 len = (u32)err->ErrorContextCount * (offsetof(struct smb2_error_context_rsp,
36 ErrorContextData) +
37 sizeof(struct smb2_symlink_err_rsp));
38 if (le32_to_cpu(err->ByteCount) < len || iov->iov_len < len + sizeof(*err) + 1)
39 return ERR_PTR(-EINVAL);
40
41 p = (struct smb2_error_context_rsp *)err->ErrorData;
42 end = (struct smb2_error_context_rsp *)((u8 *)err + iov->iov_len);
43 do {
44 if (le32_to_cpu(p->ErrorId) == SMB2_ERROR_ID_DEFAULT) {
45 sym = (struct smb2_symlink_err_rsp *)&p->ErrorContextData;
46 break;
47 }
48 cifs_dbg(FYI, "%s: skipping unhandled error context: 0x%x\n",
49 __func__, le32_to_cpu(p->ErrorId));
50
51 len = ALIGN(le32_to_cpu(p->ErrorDataLength), 8);
52 p = (struct smb2_error_context_rsp *)((u8 *)&p->ErrorContextData + len);
53 } while (p < end);
54 } else if (le32_to_cpu(err->ByteCount) >= sizeof(*sym) &&
55 iov->iov_len >= SMB2_SYMLINK_STRUCT_SIZE) {
56 sym = (struct smb2_symlink_err_rsp *)err->ErrorData;
57 }
58
59 if (!IS_ERR(sym) && (le32_to_cpu(sym->SymLinkErrorTag) != SYMLINK_ERROR_TAG ||
60 le32_to_cpu(sym->ReparseTag) != IO_REPARSE_TAG_SYMLINK))
61 sym = ERR_PTR(-EINVAL);
62
63 return sym;
64}
65
66int smb2_parse_symlink_response(struct cifs_sb_info *cifs_sb, const struct kvec *iov,
67 const char *full_path, char **path)
68{
69 struct smb2_symlink_err_rsp *sym;
70 unsigned int sub_offs, sub_len;
71 unsigned int print_offs, print_len;
72
73 if (!cifs_sb || !iov || !iov->iov_base || !iov->iov_len || !path)
74 return -EINVAL;
75
76 sym = symlink_data(iov);
77 if (IS_ERR(sym))
78 return PTR_ERR(sym);
79
80 sub_len = le16_to_cpu(sym->SubstituteNameLength);
81 sub_offs = le16_to_cpu(sym->SubstituteNameOffset);
82 print_len = le16_to_cpu(sym->PrintNameLength);
83 print_offs = le16_to_cpu(sym->PrintNameOffset);
84
85 if (iov->iov_len < SMB2_SYMLINK_STRUCT_SIZE + sub_offs + sub_len ||
86 iov->iov_len < SMB2_SYMLINK_STRUCT_SIZE + print_offs + print_len)
87 return -EINVAL;
88
89 return smb2_parse_native_symlink(path,
90 (char *)sym->PathBuffer + sub_offs,
91 sub_len,
92 true,
93 le32_to_cpu(sym->Flags) & SYMLINK_FLAG_RELATIVE,
94 full_path,
95 cifs_sb);
96}
97
98int smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms, __u32 *oplock, void *buf)
99{
100 int rc;
101 __le16 *smb2_path;
102 __u8 smb2_oplock;
103 struct cifs_open_info_data *data = buf;
104 struct smb2_file_all_info file_info = {};
105 struct smb2_file_all_info *smb2_data = data ? &file_info : NULL;
106 struct kvec err_iov = {};
107 int err_buftype = CIFS_NO_BUFFER;
108 struct cifs_fid *fid = oparms->fid;
109 struct network_resiliency_req nr_ioctl_req;
110
111 smb2_path = cifs_convert_path_to_utf16(oparms->path, oparms->cifs_sb);
112 if (smb2_path == NULL)
113 return -ENOMEM;
114
115 oparms->desired_access |= FILE_READ_ATTRIBUTES;
116 smb2_oplock = SMB2_OPLOCK_LEVEL_BATCH;
117
118 rc = SMB2_open(xid, oparms, smb2_path, &smb2_oplock, smb2_data, NULL, &err_iov,
119 &err_buftype);
120 if (rc && data) {
121 struct smb2_hdr *hdr = err_iov.iov_base;
122
123 if (unlikely(!err_iov.iov_base || err_buftype == CIFS_NO_BUFFER))
124 goto out;
125 if (hdr->Status == STATUS_STOPPED_ON_SYMLINK) {
126 rc = smb2_parse_symlink_response(oparms->cifs_sb, &err_iov,
127 oparms->path,
128 &data->symlink_target);
129 if (!rc) {
130 memset(smb2_data, 0, sizeof(*smb2_data));
131 oparms->create_options |= OPEN_REPARSE_POINT;
132 rc = SMB2_open(xid, oparms, smb2_path, &smb2_oplock, smb2_data,
133 NULL, NULL, NULL);
134 oparms->create_options &= ~OPEN_REPARSE_POINT;
135 }
136 }
137 }
138
139 if (rc)
140 goto out;
141
142 if (oparms->tcon->use_resilient) {
143 /* default timeout is 0, servers pick default (120 seconds) */
144 nr_ioctl_req.Timeout =
145 cpu_to_le32(oparms->tcon->handle_timeout);
146 nr_ioctl_req.Reserved = 0;
147 rc = SMB2_ioctl(xid, oparms->tcon, fid->persistent_fid,
148 fid->volatile_fid, FSCTL_LMR_REQUEST_RESILIENCY,
149 (char *)&nr_ioctl_req, sizeof(nr_ioctl_req),
150 CIFSMaxBufSize, NULL, NULL /* no return info */);
151 if (rc == -EOPNOTSUPP) {
152 cifs_dbg(VFS,
153 "resiliency not supported by server, disabling\n");
154 oparms->tcon->use_resilient = false;
155 } else if (rc)
156 cifs_dbg(FYI, "error %d setting resiliency\n", rc);
157
158 rc = 0;
159 }
160
161 if (smb2_data) {
162 /* if open response does not have IndexNumber field - get it */
163 if (smb2_data->IndexNumber == 0) {
164 rc = SMB2_get_srv_num(xid, oparms->tcon,
165 fid->persistent_fid,
166 fid->volatile_fid,
167 &smb2_data->IndexNumber);
168 if (rc) {
169 /*
170 * let get_inode_info disable server inode
171 * numbers
172 */
173 smb2_data->IndexNumber = 0;
174 rc = 0;
175 }
176 }
177 memcpy(&data->fi, smb2_data, sizeof(data->fi));
178 }
179
180 *oplock = smb2_oplock;
181out:
182 free_rsp_buf(err_buftype, err_iov.iov_base);
183 kfree(smb2_path);
184 return rc;
185}
186
187int
188smb2_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
189 const unsigned int xid)
190{
191 int rc = 0, stored_rc;
192 unsigned int max_num, num = 0, max_buf;
193 struct smb2_lock_element *buf, *cur;
194 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
195 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
196 struct cifsLockInfo *li, *tmp;
197 __u64 length = 1 + flock->fl_end - flock->fl_start;
198 LIST_HEAD(tmp_llist);
199
200 /*
201 * Accessing maxBuf is racy with cifs_reconnect - need to store value
202 * and check it before using.
203 */
204 max_buf = tcon->ses->server->maxBuf;
205 if (max_buf < sizeof(struct smb2_lock_element))
206 return -EINVAL;
207
208 BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
209 max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
210 max_num = max_buf / sizeof(struct smb2_lock_element);
211 buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
212 if (!buf)
213 return -ENOMEM;
214
215 cur = buf;
216
217 cifs_down_write(&cinode->lock_sem);
218 list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
219 if (flock->fl_start > li->offset ||
220 (flock->fl_start + length) <
221 (li->offset + li->length))
222 continue;
223 if (current->tgid != li->pid)
224 /*
225 * flock and OFD lock are associated with an open
226 * file description, not the process.
227 */
228 if (!(flock->c.flc_flags & (FL_FLOCK | FL_OFDLCK)))
229 continue;
230 if (cinode->can_cache_brlcks) {
231 /*
232 * We can cache brlock requests - simply remove a lock
233 * from the file's list.
234 */
235 list_del(&li->llist);
236 cifs_del_lock_waiters(li);
237 kfree(li);
238 continue;
239 }
240 cur->Length = cpu_to_le64(li->length);
241 cur->Offset = cpu_to_le64(li->offset);
242 cur->Flags = cpu_to_le32(SMB2_LOCKFLAG_UNLOCK);
243 /*
244 * We need to save a lock here to let us add it again to the
245 * file's list if the unlock range request fails on the server.
246 */
247 list_move(&li->llist, &tmp_llist);
248 if (++num == max_num) {
249 stored_rc = smb2_lockv(xid, tcon,
250 cfile->fid.persistent_fid,
251 cfile->fid.volatile_fid,
252 current->tgid, num, buf);
253 if (stored_rc) {
254 /*
255 * We failed on the unlock range request - add
256 * all locks from the tmp list to the head of
257 * the file's list.
258 */
259 cifs_move_llist(&tmp_llist,
260 &cfile->llist->locks);
261 rc = stored_rc;
262 } else
263 /*
264 * The unlock range request succeed - free the
265 * tmp list.
266 */
267 cifs_free_llist(&tmp_llist);
268 cur = buf;
269 num = 0;
270 } else
271 cur++;
272 }
273 if (num) {
274 stored_rc = smb2_lockv(xid, tcon, cfile->fid.persistent_fid,
275 cfile->fid.volatile_fid, current->tgid,
276 num, buf);
277 if (stored_rc) {
278 cifs_move_llist(&tmp_llist, &cfile->llist->locks);
279 rc = stored_rc;
280 } else
281 cifs_free_llist(&tmp_llist);
282 }
283 up_write(&cinode->lock_sem);
284
285 kfree(buf);
286 return rc;
287}
288
289static int
290smb2_push_mand_fdlocks(struct cifs_fid_locks *fdlocks, const unsigned int xid,
291 struct smb2_lock_element *buf, unsigned int max_num)
292{
293 int rc = 0, stored_rc;
294 struct cifsFileInfo *cfile = fdlocks->cfile;
295 struct cifsLockInfo *li;
296 unsigned int num = 0;
297 struct smb2_lock_element *cur = buf;
298 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
299
300 list_for_each_entry(li, &fdlocks->locks, llist) {
301 cur->Length = cpu_to_le64(li->length);
302 cur->Offset = cpu_to_le64(li->offset);
303 cur->Flags = cpu_to_le32(li->type |
304 SMB2_LOCKFLAG_FAIL_IMMEDIATELY);
305 if (++num == max_num) {
306 stored_rc = smb2_lockv(xid, tcon,
307 cfile->fid.persistent_fid,
308 cfile->fid.volatile_fid,
309 current->tgid, num, buf);
310 if (stored_rc)
311 rc = stored_rc;
312 cur = buf;
313 num = 0;
314 } else
315 cur++;
316 }
317 if (num) {
318 stored_rc = smb2_lockv(xid, tcon,
319 cfile->fid.persistent_fid,
320 cfile->fid.volatile_fid,
321 current->tgid, num, buf);
322 if (stored_rc)
323 rc = stored_rc;
324 }
325
326 return rc;
327}
328
329int
330smb2_push_mandatory_locks(struct cifsFileInfo *cfile)
331{
332 int rc = 0, stored_rc;
333 unsigned int xid;
334 unsigned int max_num, max_buf;
335 struct smb2_lock_element *buf;
336 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
337 struct cifs_fid_locks *fdlocks;
338
339 xid = get_xid();
340
341 /*
342 * Accessing maxBuf is racy with cifs_reconnect - need to store value
343 * and check it for zero before using.
344 */
345 max_buf = tlink_tcon(cfile->tlink)->ses->server->maxBuf;
346 if (max_buf < sizeof(struct smb2_lock_element)) {
347 free_xid(xid);
348 return -EINVAL;
349 }
350
351 BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
352 max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
353 max_num = max_buf / sizeof(struct smb2_lock_element);
354 buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
355 if (!buf) {
356 free_xid(xid);
357 return -ENOMEM;
358 }
359
360 list_for_each_entry(fdlocks, &cinode->llist, llist) {
361 stored_rc = smb2_push_mand_fdlocks(fdlocks, xid, buf, max_num);
362 if (stored_rc)
363 rc = stored_rc;
364 }
365
366 kfree(buf);
367 free_xid(xid);
368 return rc;
369}