1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
4  */
5 #include <linux/compat.h>
6 #include <linux/kernel.h>
7 #include <linux/errno.h>
8 #include <linux/string.h>
9 #include <linux/module.h>
10 #include <linux/blkdev.h>
11 #include <linux/capability.h>
12 #include <linux/completion.h>
13 #include <linux/cdrom.h>
14 #include <linux/ratelimit.h>
15 #include <linux/slab.h>
16 #include <linux/times.h>
17 #include <linux/uio.h>
18 #include <linux/uaccess.h>
19 
20 #include <scsi/scsi.h>
21 #include <scsi/scsi_ioctl.h>
22 #include <scsi/scsi_cmnd.h>
23 #include <scsi/sg.h>
24 
25 struct blk_cmd_filter {
26 	unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
27 	unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
28 };
29 
30 static struct blk_cmd_filter blk_default_cmd_filter;
31 
32 /* Command group 3 is reserved and should never be used.  */
33 const unsigned char scsi_command_size_tbl[8] =
34 {
35 	6, 10, 10, 12,
36 	16, 12, 10, 10
37 };
38 EXPORT_SYMBOL(scsi_command_size_tbl);
39 
sg_get_version(int __user * p)40 static int sg_get_version(int __user *p)
41 {
42 	static const int sg_version_num = 30527;
43 	return put_user(sg_version_num, p);
44 }
45 
scsi_get_idlun(struct request_queue * q,int __user * p)46 static int scsi_get_idlun(struct request_queue *q, int __user *p)
47 {
48 	return put_user(0, p);
49 }
50 
scsi_get_bus(struct request_queue * q,int __user * p)51 static int scsi_get_bus(struct request_queue *q, int __user *p)
52 {
53 	return put_user(0, p);
54 }
55 
sg_get_timeout(struct request_queue * q)56 static int sg_get_timeout(struct request_queue *q)
57 {
58 	return jiffies_to_clock_t(q->sg_timeout);
59 }
60 
sg_set_timeout(struct request_queue * q,int __user * p)61 static int sg_set_timeout(struct request_queue *q, int __user *p)
62 {
63 	int timeout, err = get_user(timeout, p);
64 
65 	if (!err)
66 		q->sg_timeout = clock_t_to_jiffies(timeout);
67 
68 	return err;
69 }
70 
max_sectors_bytes(struct request_queue * q)71 static int max_sectors_bytes(struct request_queue *q)
72 {
73 	unsigned int max_sectors = queue_max_sectors(q);
74 
75 	max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
76 
77 	return max_sectors << 9;
78 }
79 
sg_get_reserved_size(struct request_queue * q,int __user * p)80 static int sg_get_reserved_size(struct request_queue *q, int __user *p)
81 {
82 	int val = min_t(int, q->sg_reserved_size, max_sectors_bytes(q));
83 
84 	return put_user(val, p);
85 }
86 
sg_set_reserved_size(struct request_queue * q,int __user * p)87 static int sg_set_reserved_size(struct request_queue *q, int __user *p)
88 {
89 	int size, err = get_user(size, p);
90 
91 	if (err)
92 		return err;
93 
94 	if (size < 0)
95 		return -EINVAL;
96 
97 	q->sg_reserved_size = min(size, max_sectors_bytes(q));
98 	return 0;
99 }
100 
101 /*
102  * will always return that we are ATAPI even for a real SCSI drive, I'm not
103  * so sure this is worth doing anything about (why would you care??)
104  */
sg_emulated_host(struct request_queue * q,int __user * p)105 static int sg_emulated_host(struct request_queue *q, int __user *p)
106 {
107 	return put_user(1, p);
108 }
109 
blk_set_cmd_filter_defaults(struct blk_cmd_filter * filter)110 static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
111 {
112 	/* Basic read-only commands */
113 	__set_bit(TEST_UNIT_READY, filter->read_ok);
114 	__set_bit(REQUEST_SENSE, filter->read_ok);
115 	__set_bit(READ_6, filter->read_ok);
116 	__set_bit(READ_10, filter->read_ok);
117 	__set_bit(READ_12, filter->read_ok);
118 	__set_bit(READ_16, filter->read_ok);
119 	__set_bit(READ_BUFFER, filter->read_ok);
120 	__set_bit(READ_DEFECT_DATA, filter->read_ok);
121 	__set_bit(READ_CAPACITY, filter->read_ok);
122 	__set_bit(READ_LONG, filter->read_ok);
123 	__set_bit(INQUIRY, filter->read_ok);
124 	__set_bit(MODE_SENSE, filter->read_ok);
125 	__set_bit(MODE_SENSE_10, filter->read_ok);
126 	__set_bit(LOG_SENSE, filter->read_ok);
127 	__set_bit(START_STOP, filter->read_ok);
128 	__set_bit(GPCMD_VERIFY_10, filter->read_ok);
129 	__set_bit(VERIFY_16, filter->read_ok);
130 	__set_bit(REPORT_LUNS, filter->read_ok);
131 	__set_bit(SERVICE_ACTION_IN_16, filter->read_ok);
132 	__set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
133 	__set_bit(MAINTENANCE_IN, filter->read_ok);
134 	__set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
135 
136 	/* Audio CD commands */
137 	__set_bit(GPCMD_PLAY_CD, filter->read_ok);
138 	__set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
139 	__set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
140 	__set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
141 	__set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
142 
143 	/* CD/DVD data reading */
144 	__set_bit(GPCMD_READ_CD, filter->read_ok);
145 	__set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
146 	__set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
147 	__set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
148 	__set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
149 	__set_bit(GPCMD_READ_HEADER, filter->read_ok);
150 	__set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
151 	__set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
152 	__set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
153 	__set_bit(GPCMD_REPORT_KEY, filter->read_ok);
154 	__set_bit(GPCMD_SCAN, filter->read_ok);
155 	__set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
156 	__set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
157 	__set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
158 	__set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
159 	__set_bit(GPCMD_SEEK, filter->read_ok);
160 	__set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
161 
162 	/* Basic writing commands */
163 	__set_bit(WRITE_6, filter->write_ok);
164 	__set_bit(WRITE_10, filter->write_ok);
165 	__set_bit(WRITE_VERIFY, filter->write_ok);
166 	__set_bit(WRITE_12, filter->write_ok);
167 	__set_bit(WRITE_VERIFY_12, filter->write_ok);
168 	__set_bit(WRITE_16, filter->write_ok);
169 	__set_bit(WRITE_LONG, filter->write_ok);
170 	__set_bit(WRITE_LONG_2, filter->write_ok);
171 	__set_bit(WRITE_SAME, filter->write_ok);
172 	__set_bit(WRITE_SAME_16, filter->write_ok);
173 	__set_bit(WRITE_SAME_32, filter->write_ok);
174 	__set_bit(ERASE, filter->write_ok);
175 	__set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
176 	__set_bit(MODE_SELECT, filter->write_ok);
177 	__set_bit(LOG_SELECT, filter->write_ok);
178 	__set_bit(GPCMD_BLANK, filter->write_ok);
179 	__set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
180 	__set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
181 	__set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
182 	__set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
183 	__set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
184 	__set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
185 	__set_bit(GPCMD_SEND_EVENT, filter->write_ok);
186 	__set_bit(GPCMD_SEND_KEY, filter->write_ok);
187 	__set_bit(GPCMD_SEND_OPC, filter->write_ok);
188 	__set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
189 	__set_bit(GPCMD_SET_SPEED, filter->write_ok);
190 	__set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
191 	__set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
192 	__set_bit(GPCMD_SET_STREAMING, filter->write_ok);
193 	__set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
194 
195 	/* ZBC Commands */
196 	__set_bit(ZBC_OUT, filter->write_ok);
197 	__set_bit(ZBC_IN, filter->read_ok);
198 }
199 
blk_verify_command(unsigned char * cmd,fmode_t mode)200 int blk_verify_command(unsigned char *cmd, fmode_t mode)
201 {
202 	struct blk_cmd_filter *filter = &blk_default_cmd_filter;
203 
204 	/* root can do any command. */
205 	if (capable(CAP_SYS_RAWIO))
206 		return 0;
207 
208 	/* Anybody who can open the device can do a read-safe command */
209 	if (test_bit(cmd[0], filter->read_ok))
210 		return 0;
211 
212 	/* Write-safe commands require a writable open */
213 	if (test_bit(cmd[0], filter->write_ok) && (mode & FMODE_WRITE))
214 		return 0;
215 
216 	return -EPERM;
217 }
218 EXPORT_SYMBOL(blk_verify_command);
219 
blk_fill_sghdr_rq(struct request_queue * q,struct request * rq,struct sg_io_hdr * hdr,fmode_t mode)220 static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
221 			     struct sg_io_hdr *hdr, fmode_t mode)
222 {
223 	struct scsi_request *req = scsi_req(rq);
224 
225 	if (copy_from_user(req->cmd, hdr->cmdp, hdr->cmd_len))
226 		return -EFAULT;
227 	if (blk_verify_command(req->cmd, mode))
228 		return -EPERM;
229 
230 	/*
231 	 * fill in request structure
232 	 */
233 	req->cmd_len = hdr->cmd_len;
234 
235 	rq->timeout = msecs_to_jiffies(hdr->timeout);
236 	if (!rq->timeout)
237 		rq->timeout = q->sg_timeout;
238 	if (!rq->timeout)
239 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
240 	if (rq->timeout < BLK_MIN_SG_TIMEOUT)
241 		rq->timeout = BLK_MIN_SG_TIMEOUT;
242 
243 	return 0;
244 }
245 
blk_complete_sghdr_rq(struct request * rq,struct sg_io_hdr * hdr,struct bio * bio)246 static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
247 				 struct bio *bio)
248 {
249 	struct scsi_request *req = scsi_req(rq);
250 	int r, ret = 0;
251 
252 	/*
253 	 * fill in all the output members
254 	 */
255 	hdr->status = req->result & 0xff;
256 	hdr->masked_status = status_byte(req->result);
257 	hdr->msg_status = msg_byte(req->result);
258 	hdr->host_status = host_byte(req->result);
259 	hdr->driver_status = driver_byte(req->result);
260 	hdr->info = 0;
261 	if (hdr->masked_status || hdr->host_status || hdr->driver_status)
262 		hdr->info |= SG_INFO_CHECK;
263 	hdr->resid = req->resid_len;
264 	hdr->sb_len_wr = 0;
265 
266 	if (req->sense_len && hdr->sbp) {
267 		int len = min((unsigned int) hdr->mx_sb_len, req->sense_len);
268 
269 		if (!copy_to_user(hdr->sbp, req->sense, len))
270 			hdr->sb_len_wr = len;
271 		else
272 			ret = -EFAULT;
273 	}
274 
275 	r = blk_rq_unmap_user(bio);
276 	if (!ret)
277 		ret = r;
278 
279 	return ret;
280 }
281 
sg_io(struct request_queue * q,struct gendisk * bd_disk,struct sg_io_hdr * hdr,fmode_t mode)282 static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
283 		struct sg_io_hdr *hdr, fmode_t mode)
284 {
285 	unsigned long start_time;
286 	ssize_t ret = 0;
287 	int writing = 0;
288 	int at_head = 0;
289 	struct request *rq;
290 	struct scsi_request *req;
291 	struct bio *bio;
292 
293 	if (hdr->interface_id != 'S')
294 		return -EINVAL;
295 
296 	if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
297 		return -EIO;
298 
299 	if (hdr->dxfer_len)
300 		switch (hdr->dxfer_direction) {
301 		default:
302 			return -EINVAL;
303 		case SG_DXFER_TO_DEV:
304 			writing = 1;
305 			break;
306 		case SG_DXFER_TO_FROM_DEV:
307 		case SG_DXFER_FROM_DEV:
308 			break;
309 		}
310 	if (hdr->flags & SG_FLAG_Q_AT_HEAD)
311 		at_head = 1;
312 
313 	ret = -ENOMEM;
314 	rq = blk_get_request(q, writing ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
315 	if (IS_ERR(rq))
316 		return PTR_ERR(rq);
317 	req = scsi_req(rq);
318 
319 	if (hdr->cmd_len > BLK_MAX_CDB) {
320 		req->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
321 		if (!req->cmd)
322 			goto out_put_request;
323 	}
324 
325 	ret = blk_fill_sghdr_rq(q, rq, hdr, mode);
326 	if (ret < 0)
327 		goto out_free_cdb;
328 
329 	ret = 0;
330 	if (hdr->iovec_count) {
331 		struct iov_iter i;
332 		struct iovec *iov = NULL;
333 
334 		ret = import_iovec(rq_data_dir(rq), hdr->dxferp,
335 				   hdr->iovec_count, 0, &iov, &i);
336 		if (ret < 0)
337 			goto out_free_cdb;
338 
339 		/* SG_IO howto says that the shorter of the two wins */
340 		iov_iter_truncate(&i, hdr->dxfer_len);
341 
342 		ret = blk_rq_map_user_iov(q, rq, NULL, &i, GFP_KERNEL);
343 		kfree(iov);
344 	} else if (hdr->dxfer_len)
345 		ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
346 				      GFP_KERNEL);
347 
348 	if (ret)
349 		goto out_free_cdb;
350 
351 	bio = rq->bio;
352 	req->retries = 0;
353 
354 	start_time = jiffies;
355 
356 	/* ignore return value. All information is passed back to caller
357 	 * (if he doesn't check that is his problem).
358 	 * N.B. a non-zero SCSI status is _not_ necessarily an error.
359 	 */
360 	blk_execute_rq(q, bd_disk, rq, at_head);
361 
362 	hdr->duration = jiffies_to_msecs(jiffies - start_time);
363 
364 	ret = blk_complete_sghdr_rq(rq, hdr, bio);
365 
366 out_free_cdb:
367 	scsi_req_free_cmd(req);
368 out_put_request:
369 	blk_put_request(rq);
370 	return ret;
371 }
372 
373 /**
374  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
375  * @q:		request queue to send scsi commands down
376  * @disk:	gendisk to operate on (option)
377  * @mode:	mode used to open the file through which the ioctl has been
378  *		submitted
379  * @sic:	userspace structure describing the command to perform
380  *
381  * Send down the scsi command described by @sic to the device below
382  * the request queue @q.  If @file is non-NULL it's used to perform
383  * fine-grained permission checks that allow users to send down
384  * non-destructive SCSI commands.  If the caller has a struct gendisk
385  * available it should be passed in as @disk to allow the low level
386  * driver to use the information contained in it.  A non-NULL @disk
387  * is only allowed if the caller knows that the low level driver doesn't
388  * need it (e.g. in the scsi subsystem).
389  *
390  * Notes:
391  *   -  This interface is deprecated - users should use the SG_IO
392  *      interface instead, as this is a more flexible approach to
393  *      performing SCSI commands on a device.
394  *   -  The SCSI command length is determined by examining the 1st byte
395  *      of the given command. There is no way to override this.
396  *   -  Data transfers are limited to PAGE_SIZE
397  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
398  *      accommodate the sense buffer when an error occurs.
399  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
400  *      old code will not be surprised.
401  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
402  *      a negative return and the Unix error code in 'errno'.
403  *      If the SCSI command succeeds then 0 is returned.
404  *      Positive numbers returned are the compacted SCSI error codes (4
405  *      bytes in one int) where the lowest byte is the SCSI status.
406  */
sg_scsi_ioctl(struct request_queue * q,struct gendisk * disk,fmode_t mode,struct scsi_ioctl_command __user * sic)407 int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
408 		struct scsi_ioctl_command __user *sic)
409 {
410 	enum { OMAX_SB_LEN = 16 };	/* For backward compatibility */
411 	struct request *rq;
412 	struct scsi_request *req;
413 	int err;
414 	unsigned int in_len, out_len, bytes, opcode, cmdlen;
415 	char *buffer = NULL;
416 
417 	if (!sic)
418 		return -EINVAL;
419 
420 	/*
421 	 * get in an out lengths, verify they don't exceed a page worth of data
422 	 */
423 	if (get_user(in_len, &sic->inlen))
424 		return -EFAULT;
425 	if (get_user(out_len, &sic->outlen))
426 		return -EFAULT;
427 	if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
428 		return -EINVAL;
429 	if (get_user(opcode, sic->data))
430 		return -EFAULT;
431 
432 	bytes = max(in_len, out_len);
433 	if (bytes) {
434 		buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
435 		if (!buffer)
436 			return -ENOMEM;
437 
438 	}
439 
440 	rq = blk_get_request(q, in_len ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
441 	if (IS_ERR(rq)) {
442 		err = PTR_ERR(rq);
443 		goto error_free_buffer;
444 	}
445 	req = scsi_req(rq);
446 
447 	cmdlen = COMMAND_SIZE(opcode);
448 
449 	/*
450 	 * get command and data to send to device, if any
451 	 */
452 	err = -EFAULT;
453 	req->cmd_len = cmdlen;
454 	if (copy_from_user(req->cmd, sic->data, cmdlen))
455 		goto error;
456 
457 	if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
458 		goto error;
459 
460 	err = blk_verify_command(req->cmd, mode);
461 	if (err)
462 		goto error;
463 
464 	/* default.  possible overriden later */
465 	req->retries = 5;
466 
467 	switch (opcode) {
468 	case SEND_DIAGNOSTIC:
469 	case FORMAT_UNIT:
470 		rq->timeout = FORMAT_UNIT_TIMEOUT;
471 		req->retries = 1;
472 		break;
473 	case START_STOP:
474 		rq->timeout = START_STOP_TIMEOUT;
475 		break;
476 	case MOVE_MEDIUM:
477 		rq->timeout = MOVE_MEDIUM_TIMEOUT;
478 		break;
479 	case READ_ELEMENT_STATUS:
480 		rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
481 		break;
482 	case READ_DEFECT_DATA:
483 		rq->timeout = READ_DEFECT_DATA_TIMEOUT;
484 		req->retries = 1;
485 		break;
486 	default:
487 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
488 		break;
489 	}
490 
491 	if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, GFP_NOIO)) {
492 		err = DRIVER_ERROR << 24;
493 		goto error;
494 	}
495 
496 	blk_execute_rq(q, disk, rq, 0);
497 
498 	err = req->result & 0xff;	/* only 8 bit SCSI status */
499 	if (err) {
500 		if (req->sense_len && req->sense) {
501 			bytes = (OMAX_SB_LEN > req->sense_len) ?
502 				req->sense_len : OMAX_SB_LEN;
503 			if (copy_to_user(sic->data, req->sense, bytes))
504 				err = -EFAULT;
505 		}
506 	} else {
507 		if (copy_to_user(sic->data, buffer, out_len))
508 			err = -EFAULT;
509 	}
510 
511 error:
512 	blk_put_request(rq);
513 
514 error_free_buffer:
515 	kfree(buffer);
516 
517 	return err;
518 }
519 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
520 
521 /* Send basic block requests */
__blk_send_generic(struct request_queue * q,struct gendisk * bd_disk,int cmd,int data)522 static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
523 			      int cmd, int data)
524 {
525 	struct request *rq;
526 	int err;
527 
528 	rq = blk_get_request(q, REQ_OP_SCSI_OUT, 0);
529 	if (IS_ERR(rq))
530 		return PTR_ERR(rq);
531 	rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
532 	scsi_req(rq)->cmd[0] = cmd;
533 	scsi_req(rq)->cmd[4] = data;
534 	scsi_req(rq)->cmd_len = 6;
535 	blk_execute_rq(q, bd_disk, rq, 0);
536 	err = scsi_req(rq)->result ? -EIO : 0;
537 	blk_put_request(rq);
538 
539 	return err;
540 }
541 
blk_send_start_stop(struct request_queue * q,struct gendisk * bd_disk,int data)542 static inline int blk_send_start_stop(struct request_queue *q,
543 				      struct gendisk *bd_disk, int data)
544 {
545 	return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
546 }
547 
put_sg_io_hdr(const struct sg_io_hdr * hdr,void __user * argp)548 int put_sg_io_hdr(const struct sg_io_hdr *hdr, void __user *argp)
549 {
550 #ifdef CONFIG_COMPAT
551 	if (in_compat_syscall()) {
552 		struct compat_sg_io_hdr hdr32 =  {
553 			.interface_id	 = hdr->interface_id,
554 			.dxfer_direction = hdr->dxfer_direction,
555 			.cmd_len	 = hdr->cmd_len,
556 			.mx_sb_len	 = hdr->mx_sb_len,
557 			.iovec_count	 = hdr->iovec_count,
558 			.dxfer_len	 = hdr->dxfer_len,
559 			.dxferp		 = (uintptr_t)hdr->dxferp,
560 			.cmdp		 = (uintptr_t)hdr->cmdp,
561 			.sbp		 = (uintptr_t)hdr->sbp,
562 			.timeout	 = hdr->timeout,
563 			.flags		 = hdr->flags,
564 			.pack_id	 = hdr->pack_id,
565 			.usr_ptr	 = (uintptr_t)hdr->usr_ptr,
566 			.status		 = hdr->status,
567 			.masked_status	 = hdr->masked_status,
568 			.msg_status	 = hdr->msg_status,
569 			.sb_len_wr	 = hdr->sb_len_wr,
570 			.host_status	 = hdr->host_status,
571 			.driver_status	 = hdr->driver_status,
572 			.resid		 = hdr->resid,
573 			.duration	 = hdr->duration,
574 			.info		 = hdr->info,
575 		};
576 
577 		if (copy_to_user(argp, &hdr32, sizeof(hdr32)))
578 			return -EFAULT;
579 
580 		return 0;
581 	}
582 #endif
583 
584 	if (copy_to_user(argp, hdr, sizeof(*hdr)))
585 		return -EFAULT;
586 
587 	return 0;
588 }
589 EXPORT_SYMBOL(put_sg_io_hdr);
590 
get_sg_io_hdr(struct sg_io_hdr * hdr,const void __user * argp)591 int get_sg_io_hdr(struct sg_io_hdr *hdr, const void __user *argp)
592 {
593 #ifdef CONFIG_COMPAT
594 	struct compat_sg_io_hdr hdr32;
595 
596 	if (in_compat_syscall()) {
597 		if (copy_from_user(&hdr32, argp, sizeof(hdr32)))
598 			return -EFAULT;
599 
600 		*hdr = (struct sg_io_hdr) {
601 			.interface_id	 = hdr32.interface_id,
602 			.dxfer_direction = hdr32.dxfer_direction,
603 			.cmd_len	 = hdr32.cmd_len,
604 			.mx_sb_len	 = hdr32.mx_sb_len,
605 			.iovec_count	 = hdr32.iovec_count,
606 			.dxfer_len	 = hdr32.dxfer_len,
607 			.dxferp		 = compat_ptr(hdr32.dxferp),
608 			.cmdp		 = compat_ptr(hdr32.cmdp),
609 			.sbp		 = compat_ptr(hdr32.sbp),
610 			.timeout	 = hdr32.timeout,
611 			.flags		 = hdr32.flags,
612 			.pack_id	 = hdr32.pack_id,
613 			.usr_ptr	 = compat_ptr(hdr32.usr_ptr),
614 			.status		 = hdr32.status,
615 			.masked_status	 = hdr32.masked_status,
616 			.msg_status	 = hdr32.msg_status,
617 			.sb_len_wr	 = hdr32.sb_len_wr,
618 			.host_status	 = hdr32.host_status,
619 			.driver_status	 = hdr32.driver_status,
620 			.resid		 = hdr32.resid,
621 			.duration	 = hdr32.duration,
622 			.info		 = hdr32.info,
623 		};
624 
625 		return 0;
626 	}
627 #endif
628 
629 	if (copy_from_user(hdr, argp, sizeof(*hdr)))
630 		return -EFAULT;
631 
632 	return 0;
633 }
634 EXPORT_SYMBOL(get_sg_io_hdr);
635 
636 #ifdef CONFIG_COMPAT
637 struct compat_cdrom_generic_command {
638 	unsigned char	cmd[CDROM_PACKET_SIZE];
639 	compat_caddr_t	buffer;
640 	compat_uint_t	buflen;
641 	compat_int_t	stat;
642 	compat_caddr_t	sense;
643 	unsigned char	data_direction;
644 	unsigned char	pad[3];
645 	compat_int_t	quiet;
646 	compat_int_t	timeout;
647 	compat_caddr_t	unused;
648 };
649 #endif
650 
scsi_get_cdrom_generic_arg(struct cdrom_generic_command * cgc,const void __user * arg)651 static int scsi_get_cdrom_generic_arg(struct cdrom_generic_command *cgc,
652 				      const void __user *arg)
653 {
654 #ifdef CONFIG_COMPAT
655 	if (in_compat_syscall()) {
656 		struct compat_cdrom_generic_command cgc32;
657 
658 		if (copy_from_user(&cgc32, arg, sizeof(cgc32)))
659 			return -EFAULT;
660 
661 		*cgc = (struct cdrom_generic_command) {
662 			.buffer		= compat_ptr(cgc32.buffer),
663 			.buflen		= cgc32.buflen,
664 			.stat		= cgc32.stat,
665 			.sense		= compat_ptr(cgc32.sense),
666 			.data_direction	= cgc32.data_direction,
667 			.quiet		= cgc32.quiet,
668 			.timeout	= cgc32.timeout,
669 			.unused		= compat_ptr(cgc32.unused),
670 		};
671 		memcpy(&cgc->cmd, &cgc32.cmd, CDROM_PACKET_SIZE);
672 		return 0;
673 	}
674 #endif
675 	if (copy_from_user(cgc, arg, sizeof(*cgc)))
676 		return -EFAULT;
677 
678 	return 0;
679 }
680 
scsi_put_cdrom_generic_arg(const struct cdrom_generic_command * cgc,void __user * arg)681 static int scsi_put_cdrom_generic_arg(const struct cdrom_generic_command *cgc,
682 				      void __user *arg)
683 {
684 #ifdef CONFIG_COMPAT
685 	if (in_compat_syscall()) {
686 		struct compat_cdrom_generic_command cgc32 = {
687 			.buffer		= (uintptr_t)(cgc->buffer),
688 			.buflen		= cgc->buflen,
689 			.stat		= cgc->stat,
690 			.sense		= (uintptr_t)(cgc->sense),
691 			.data_direction	= cgc->data_direction,
692 			.quiet		= cgc->quiet,
693 			.timeout	= cgc->timeout,
694 			.unused		= (uintptr_t)(cgc->unused),
695 		};
696 		memcpy(&cgc32.cmd, &cgc->cmd, CDROM_PACKET_SIZE);
697 
698 		if (copy_to_user(arg, &cgc32, sizeof(cgc32)))
699 			return -EFAULT;
700 
701 		return 0;
702 	}
703 #endif
704 	if (copy_to_user(arg, cgc, sizeof(*cgc)))
705 		return -EFAULT;
706 
707 	return 0;
708 }
709 
scsi_cdrom_send_packet(struct request_queue * q,struct gendisk * bd_disk,fmode_t mode,void __user * arg)710 static int scsi_cdrom_send_packet(struct request_queue *q,
711 				  struct gendisk *bd_disk,
712 				  fmode_t mode, void __user *arg)
713 {
714 	struct cdrom_generic_command cgc;
715 	struct sg_io_hdr hdr;
716 	int err;
717 
718 	err = scsi_get_cdrom_generic_arg(&cgc, arg);
719 	if (err)
720 		return err;
721 
722 	cgc.timeout = clock_t_to_jiffies(cgc.timeout);
723 	memset(&hdr, 0, sizeof(hdr));
724 	hdr.interface_id = 'S';
725 	hdr.cmd_len = sizeof(cgc.cmd);
726 	hdr.dxfer_len = cgc.buflen;
727 	switch (cgc.data_direction) {
728 		case CGC_DATA_UNKNOWN:
729 			hdr.dxfer_direction = SG_DXFER_UNKNOWN;
730 			break;
731 		case CGC_DATA_WRITE:
732 			hdr.dxfer_direction = SG_DXFER_TO_DEV;
733 			break;
734 		case CGC_DATA_READ:
735 			hdr.dxfer_direction = SG_DXFER_FROM_DEV;
736 			break;
737 		case CGC_DATA_NONE:
738 			hdr.dxfer_direction = SG_DXFER_NONE;
739 			break;
740 		default:
741 			return -EINVAL;
742 	}
743 
744 	hdr.dxferp = cgc.buffer;
745 	hdr.sbp = cgc.sense;
746 	if (hdr.sbp)
747 		hdr.mx_sb_len = sizeof(struct request_sense);
748 	hdr.timeout = jiffies_to_msecs(cgc.timeout);
749 	hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
750 	hdr.cmd_len = sizeof(cgc.cmd);
751 
752 	err = sg_io(q, bd_disk, &hdr, mode);
753 	if (err == -EFAULT)
754 		return -EFAULT;
755 
756 	if (hdr.status)
757 		return -EIO;
758 
759 	cgc.stat = err;
760 	cgc.buflen = hdr.resid;
761 	if (scsi_put_cdrom_generic_arg(&cgc, arg))
762 		return -EFAULT;
763 
764 	return err;
765 }
766 
scsi_cmd_ioctl(struct request_queue * q,struct gendisk * bd_disk,fmode_t mode,unsigned int cmd,void __user * arg)767 int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
768 		   unsigned int cmd, void __user *arg)
769 {
770 	int err;
771 
772 	if (!q)
773 		return -ENXIO;
774 
775 	switch (cmd) {
776 		/*
777 		 * new sgv3 interface
778 		 */
779 		case SG_GET_VERSION_NUM:
780 			err = sg_get_version(arg);
781 			break;
782 		case SCSI_IOCTL_GET_IDLUN:
783 			err = scsi_get_idlun(q, arg);
784 			break;
785 		case SCSI_IOCTL_GET_BUS_NUMBER:
786 			err = scsi_get_bus(q, arg);
787 			break;
788 		case SG_SET_TIMEOUT:
789 			err = sg_set_timeout(q, arg);
790 			break;
791 		case SG_GET_TIMEOUT:
792 			err = sg_get_timeout(q);
793 			break;
794 		case SG_GET_RESERVED_SIZE:
795 			err = sg_get_reserved_size(q, arg);
796 			break;
797 		case SG_SET_RESERVED_SIZE:
798 			err = sg_set_reserved_size(q, arg);
799 			break;
800 		case SG_EMULATED_HOST:
801 			err = sg_emulated_host(q, arg);
802 			break;
803 		case SG_IO: {
804 			struct sg_io_hdr hdr;
805 
806 			err = get_sg_io_hdr(&hdr, arg);
807 			if (err)
808 				break;
809 			err = sg_io(q, bd_disk, &hdr, mode);
810 			if (err == -EFAULT)
811 				break;
812 
813 			if (put_sg_io_hdr(&hdr, arg))
814 				err = -EFAULT;
815 			break;
816 		}
817 		case CDROM_SEND_PACKET:
818 			err = scsi_cdrom_send_packet(q, bd_disk, mode, arg);
819 			break;
820 
821 		/*
822 		 * old junk scsi send command ioctl
823 		 */
824 		case SCSI_IOCTL_SEND_COMMAND:
825 			printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
826 			err = -EINVAL;
827 			if (!arg)
828 				break;
829 
830 			err = sg_scsi_ioctl(q, bd_disk, mode, arg);
831 			break;
832 		case CDROMCLOSETRAY:
833 			err = blk_send_start_stop(q, bd_disk, 0x03);
834 			break;
835 		case CDROMEJECT:
836 			err = blk_send_start_stop(q, bd_disk, 0x02);
837 			break;
838 		default:
839 			err = -ENOTTY;
840 	}
841 
842 	return err;
843 }
844 EXPORT_SYMBOL(scsi_cmd_ioctl);
845 
scsi_verify_blk_ioctl(struct block_device * bd,unsigned int cmd)846 int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
847 {
848 	if (bd && !bdev_is_partition(bd))
849 		return 0;
850 
851 	if (capable(CAP_SYS_RAWIO))
852 		return 0;
853 
854 	return -ENOIOCTLCMD;
855 }
856 EXPORT_SYMBOL(scsi_verify_blk_ioctl);
857 
scsi_cmd_blk_ioctl(struct block_device * bd,fmode_t mode,unsigned int cmd,void __user * arg)858 int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
859 		       unsigned int cmd, void __user *arg)
860 {
861 	int ret;
862 
863 	ret = scsi_verify_blk_ioctl(bd, cmd);
864 	if (ret < 0)
865 		return ret;
866 
867 	return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
868 }
869 EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
870 
871 /**
872  * scsi_req_init - initialize certain fields of a scsi_request structure
873  * @req: Pointer to a scsi_request structure.
874  * Initializes .__cmd[], .cmd, .cmd_len and .sense_len but no other members
875  * of struct scsi_request.
876  */
scsi_req_init(struct scsi_request * req)877 void scsi_req_init(struct scsi_request *req)
878 {
879 	memset(req->__cmd, 0, sizeof(req->__cmd));
880 	req->cmd = req->__cmd;
881 	req->cmd_len = BLK_MAX_CDB;
882 	req->sense_len = 0;
883 }
884 EXPORT_SYMBOL(scsi_req_init);
885 
blk_scsi_ioctl_init(void)886 static int __init blk_scsi_ioctl_init(void)
887 {
888 	blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
889 	return 0;
890 }
891 fs_initcall(blk_scsi_ioctl_init);
892