drivers/md/dm-ima.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2021 Microsoft Corporation
   4  *
   5  * Author: Tushar Sugandhi <tusharsu@linux.microsoft.com>
   6  *
   7  * File: dm-ima.c
   8  *       Enables IMA measurements for DM targets
   9  */
  10
  11 #include "dm-core.h"
  12 #include "dm-ima.h"
  13
  14 #include <linux/ima.h>
  15 #include <linux/sched/mm.h>
  16 #include <crypto/hash.h>
  17 #include <linux/crypto.h>
  18 #include <crypto/hash_info.h>
  19
  20 #define DM_MSG_PREFIX "ima"
  21
  22 /*
  23  * Internal function to prefix separator characters in input buffer with escape
  24  * character, so that they don't interfere with the construction of key-value pairs,
  25  * and clients can split the key1=val1,key2=val2,key3=val3; pairs properly.
  26  */
  27 static void fix_separator_chars(char **buf)
  28 {
  29         int l = strlen(*buf);
  30         int i, j, sp = 0;
  31
  32         for (i = 0; i < l; i++)
  33                 if ((*buf)[i] == '\\' || (*buf)[i] == ';' || (*buf)[i] == '=' || (*buf)[i] == ',')
  34                         sp++;
  35
  36         if (!sp)
  37                 return;
  38
  39         for (i = l-1, j = i+sp; i >= 0; i--) {
  40                 (*buf)[j--] = (*buf)[i];
  41                 if ((*buf)[i] == '\\' || (*buf)[i] == ';' || (*buf)[i] == '=' || (*buf)[i] == ',')
  42                         (*buf)[j--] = '\\';
  43         }
  44 }
  45
  46 /*
  47  * Internal function to allocate memory for IMA measurements.
  48  */
  49 static void *dm_ima_alloc(size_t len, gfp_t flags, bool noio)
  50 {
  51         unsigned int noio_flag;
  52         void *ptr;
  53
  54         if (noio)
  55                 noio_flag = memalloc_noio_save();
  56
  57         ptr = kzalloc(len, flags);
  58
  59         if (noio)
  60                 memalloc_noio_restore(noio_flag);
  61
  62         return ptr;
  63 }
  64
  65 /*
  66  * Internal function to allocate and copy name and uuid for IMA measurements.
  67  */
  68 static int dm_ima_alloc_and_copy_name_uuid(struct mapped_device *md, char **dev_name,
  69                                            char **dev_uuid, bool noio)
  70 {
  71         int r;
  72         *dev_name = dm_ima_alloc(DM_NAME_LEN*2, GFP_KERNEL, noio);
  73         if (!(*dev_name)) {
  74                 r = -ENOMEM;
  75                 goto error;
  76         }
  77
  78         *dev_uuid = dm_ima_alloc(DM_UUID_LEN*2, GFP_KERNEL, noio);
  79         if (!(*dev_uuid)) {
  80                 r = -ENOMEM;
  81                 goto error;
  82         }
  83
  84         r = dm_copy_name_and_uuid(md, *dev_name, *dev_uuid);
  85         if (r)
  86                 goto error;
  87
  88         fix_separator_chars(dev_name);
  89         fix_separator_chars(dev_uuid);
  90
  91         return 0;
  92 error:
  93         kfree(*dev_name);
  94         kfree(*dev_uuid);
  95         *dev_name = NULL;
  96         *dev_uuid = NULL;
  97         return r;
  98 }
  99
 100 /*
 101  * Internal function to allocate and copy device data for IMA measurements.
 102  */
 103 static int dm_ima_alloc_and_copy_device_data(struct mapped_device *md, char **device_data,
 104                                              unsigned int num_targets, bool noio)
 105 {
 106         char *dev_name = NULL, *dev_uuid = NULL;
 107         int r;
 108
 109         r = dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio);
 110         if (r)
 111                 return r;
 112
 113         *device_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
 114         if (!(*device_data)) {
 115                 r = -ENOMEM;
 116                 goto error;
 117         }
 118
 119         scnprintf(*device_data, DM_IMA_DEVICE_BUF_LEN,
 120                   "name=%s,uuid=%s,major=%d,minor=%d,minor_count=%d,num_targets=%u;",
 121                   dev_name, dev_uuid, md->disk->major, md->disk->first_minor,
 122                   md->disk->minors, num_targets);
 123 error:
 124         kfree(dev_name);
 125         kfree(dev_uuid);
 126         return r;
 127 }
 128
 129 /*
 130  * Internal wrapper function to call IMA to measure DM data.
 131  */
 132 static void dm_ima_measure_data(const char *event_name, const void *buf, size_t buf_len,
 133                                 bool noio)
 134 {
 135         unsigned int noio_flag;
 136
 137         if (noio)
 138                 noio_flag = memalloc_noio_save();
 139
 140         ima_measure_critical_data(DM_NAME, event_name, buf, buf_len,
 141                                   false, NULL, 0);
 142
 143         if (noio)
 144                 memalloc_noio_restore(noio_flag);
 145 }
 146
 147 /*
 148  * Internal function to allocate and copy current device capacity for IMA measurements.
 149  */
 150 static int dm_ima_alloc_and_copy_capacity_str(struct mapped_device *md, char **capacity_str,
 151                                               bool noio)
 152 {
 153         sector_t capacity;
 154
 155         capacity = get_capacity(md->disk);
 156
 157         *capacity_str = dm_ima_alloc(DM_IMA_DEVICE_CAPACITY_BUF_LEN, GFP_KERNEL, noio);
 158         if (!(*capacity_str))
 159                 return -ENOMEM;
 160
 161         scnprintf(*capacity_str, DM_IMA_DEVICE_BUF_LEN, "current_device_capacity=%llu;",
 162                   capacity);
 163
 164         return 0;
 165 }
 166
 167 /*
 168  * Initialize/reset the dm ima related data structure variables.
 169  */
 170 void dm_ima_reset_data(struct mapped_device *md)
 171 {
 172         memset(&(md->ima), 0, sizeof(md->ima));
 173         md->ima.dm_version_str_len = strlen(DM_IMA_VERSION_STR);
 174 }
 175
 176 /*
 177  * Build up the IMA data for each target, and finally measure.
 178  */
 179 void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags)
 180 {
 181         size_t device_data_buf_len, target_metadata_buf_len, target_data_buf_len, l = 0;
 182         char *target_metadata_buf = NULL, *target_data_buf = NULL, *digest_buf = NULL;
 183         char *ima_buf = NULL, *device_data_buf = NULL;
 184         int digest_size, last_target_measured = -1, r;
 185         status_type_t type = STATUSTYPE_IMA;
 186         size_t cur_total_buf_len = 0;
 187         unsigned int num_targets, i;
 188         SHASH_DESC_ON_STACK(shash, NULL);
 189         struct crypto_shash *tfm = NULL;
 190         u8 *digest = NULL;
 191         bool noio = false;
 192         /*
 193          * In below hash_alg_prefix_len assignment +1 is for the additional char (':'),
 194          * when prefixing the hash value with the hash algorithm name. e.g. sha256:<hash_value>.
 195          */
 196         const size_t hash_alg_prefix_len = strlen(DM_IMA_TABLE_HASH_ALG) + 1;
 197         char table_load_event_name[] = "dm_table_load";
 198
 199         ima_buf = dm_ima_alloc(DM_IMA_MEASUREMENT_BUF_LEN, GFP_KERNEL, noio);
 200         if (!ima_buf)
 201                 return;
 202
 203         target_metadata_buf = dm_ima_alloc(DM_IMA_TARGET_METADATA_BUF_LEN, GFP_KERNEL, noio);
 204         if (!target_metadata_buf)
 205                 goto error;
 206
 207         target_data_buf = dm_ima_alloc(DM_IMA_TARGET_DATA_BUF_LEN, GFP_KERNEL, noio);
 208         if (!target_data_buf)
 209                 goto error;
 210
 211         num_targets = table->num_targets;
 212
 213         if (dm_ima_alloc_and_copy_device_data(table->md, &device_data_buf, num_targets, noio))
 214                 goto error;
 215
 216         tfm = crypto_alloc_shash(DM_IMA_TABLE_HASH_ALG, 0, 0);
 217         if (IS_ERR(tfm))
 218                 goto error;
 219
 220         shash->tfm = tfm;
 221         digest_size = crypto_shash_digestsize(tfm);
 222         digest = dm_ima_alloc(digest_size, GFP_KERNEL, noio);
 223         if (!digest)
 224                 goto error;
 225
 226         r = crypto_shash_init(shash);
 227         if (r)
 228                 goto error;
 229
 230         memcpy(ima_buf + l, DM_IMA_VERSION_STR, table->md->ima.dm_version_str_len);
 231         l += table->md->ima.dm_version_str_len;
 232
 233         device_data_buf_len = strlen(device_data_buf);
 234         memcpy(ima_buf + l, device_data_buf, device_data_buf_len);
 235         l += device_data_buf_len;
 236
 237         for (i = 0; i < num_targets; i++) {
 238                 struct dm_target *ti = dm_table_get_target(table, i);
 239
 240                 last_target_measured = 0;
 241
 242                 /*
 243                  * First retrieve the target metadata.
 244                  */
 245                 scnprintf(target_metadata_buf, DM_IMA_TARGET_METADATA_BUF_LEN,
 246                           "target_index=%d,target_begin=%llu,target_len=%llu,",
 247                           i, ti->begin, ti->len);
 248                 target_metadata_buf_len = strlen(target_metadata_buf);
 249
 250                 /*
 251                  * Then retrieve the actual target data.
 252                  */
 253                 if (ti->type->status)
 254                         ti->type->status(ti, type, status_flags, target_data_buf,
 255                                          DM_IMA_TARGET_DATA_BUF_LEN);
 256                 else
 257                         target_data_buf[0] = '\0';
 258
 259                 target_data_buf_len = strlen(target_data_buf);
 260
 261                 /*
 262                  * Check if the total data can fit into the IMA buffer.
 263                  */
 264                 cur_total_buf_len = l + target_metadata_buf_len + target_data_buf_len;
 265
 266                 /*
 267                  * IMA measurements for DM targets are best-effort.
 268                  * If the total data buffered so far, including the current target,
 269                  * is too large to fit into DM_IMA_MEASUREMENT_BUF_LEN, measure what
 270                  * we have in the current buffer, and continue measuring the remaining
 271                  * targets by prefixing the device metadata again.
 272                  */
 273                 if (unlikely(cur_total_buf_len >= DM_IMA_MEASUREMENT_BUF_LEN)) {
 274                         dm_ima_measure_data(table_load_event_name, ima_buf, l, noio);
 275                         r = crypto_shash_update(shash, (const u8 *)ima_buf, l);
 276                         if (r < 0)
 277                                 goto error;
 278
 279                         memset(ima_buf, 0, DM_IMA_MEASUREMENT_BUF_LEN);
 280                         l = 0;
 281
 282                         /*
 283                          * Each new "dm_table_load" entry in IMA log should have device data
 284                          * prefix, so that multiple records from the same "dm_table_load" for
 285                          * a given device can be linked together.
 286                          */
 287                         memcpy(ima_buf + l, DM_IMA_VERSION_STR, table->md->ima.dm_version_str_len);
 288                         l += table->md->ima.dm_version_str_len;
 289
 290                         memcpy(ima_buf + l, device_data_buf, device_data_buf_len);
 291                         l += device_data_buf_len;
 292
 293                         /*
 294                          * If this iteration of the for loop turns out to be the last target
 295                          * in the table, dm_ima_measure_data("dm_table_load", ...) doesn't need
 296                          * to be called again, just the hash needs to be finalized.
 297                          * "last_target_measured" tracks this state.
 298                          */
 299                         last_target_measured = 1;
 300                 }
 301
 302                 /*
 303                  * Fill-in all the target metadata, so that multiple targets for the same
 304                  * device can be linked together.
 305                  */
 306                 memcpy(ima_buf + l, target_metadata_buf, target_metadata_buf_len);
 307                 l += target_metadata_buf_len;
 308
 309                 memcpy(ima_buf + l, target_data_buf, target_data_buf_len);
 310                 l += target_data_buf_len;
 311         }
 312
 313         if (!last_target_measured) {
 314                 dm_ima_measure_data(table_load_event_name, ima_buf, l, noio);
 315
 316                 r = crypto_shash_update(shash, (const u8 *)ima_buf, l);
 317                 if (r < 0)
 318                         goto error;
 319         }
 320
 321         /*
 322          * Finalize the table hash, and store it in table->md->ima.inactive_table.hash,
 323          * so that the table data can be verified against the future device state change
 324          * events, e.g. resume, rename, remove, table-clear etc.
 325          */
 326         r = crypto_shash_final(shash, digest);
 327         if (r < 0)
 328                 goto error;
 329
 330         digest_buf = dm_ima_alloc((digest_size*2) + hash_alg_prefix_len + 1, GFP_KERNEL, noio);
 331
 332         if (!digest_buf)
 333                 goto error;
 334
 335         snprintf(digest_buf, hash_alg_prefix_len + 1, "%s:", DM_IMA_TABLE_HASH_ALG);
 336
 337         for (i = 0; i < digest_size; i++)
 338                 snprintf((digest_buf + hash_alg_prefix_len + (i*2)), 3, "%02x", digest[i]);
 339
 340         if (table->md->ima.active_table.hash != table->md->ima.inactive_table.hash)
 341                 kfree(table->md->ima.inactive_table.hash);
 342
 343         table->md->ima.inactive_table.hash = digest_buf;
 344         table->md->ima.inactive_table.hash_len = strlen(digest_buf);
 345         table->md->ima.inactive_table.num_targets = num_targets;
 346
 347         if (table->md->ima.active_table.device_metadata !=
 348             table->md->ima.inactive_table.device_metadata)
 349                 kfree(table->md->ima.inactive_table.device_metadata);
 350
 351         table->md->ima.inactive_table.device_metadata = device_data_buf;
 352         table->md->ima.inactive_table.device_metadata_len = device_data_buf_len;
 353
 354         goto exit;
 355 error:
 356         kfree(digest_buf);
 357         kfree(device_data_buf);
 358 exit:
 359         kfree(digest);
 360         if (tfm)
 361                 crypto_free_shash(tfm);
 362         kfree(ima_buf);
 363         kfree(target_metadata_buf);
 364         kfree(target_data_buf);
 365 }
 366
 367 /*
 368  * Measure IMA data on device resume.
 369  */
 370 void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
 371 {
 372         char *device_table_data, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
 373         char active[] = "active_table_hash=";
 374         unsigned int active_len = strlen(active), capacity_len = 0;
 375         unsigned int l = 0;
 376         bool noio = true;
 377         bool nodata = true;
 378         int r;
 379
 380         device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
 381         if (!device_table_data)
 382                 return;
 383
 384         r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
 385         if (r)
 386                 goto error;
 387
 388         memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
 389         l += md->ima.dm_version_str_len;
 390
 391         if (swap) {
 392                 if (md->ima.active_table.hash != md->ima.inactive_table.hash)
 393                         kfree(md->ima.active_table.hash);
 394
 395                 md->ima.active_table.hash = NULL;
 396                 md->ima.active_table.hash_len = 0;
 397
 398                 if (md->ima.active_table.device_metadata !=
 399                     md->ima.inactive_table.device_metadata)
 400                         kfree(md->ima.active_table.device_metadata);
 401
 402                 md->ima.active_table.device_metadata = NULL;
 403                 md->ima.active_table.device_metadata_len = 0;
 404                 md->ima.active_table.num_targets = 0;
 405
 406                 if (md->ima.inactive_table.hash) {
 407                         md->ima.active_table.hash = md->ima.inactive_table.hash;
 408                         md->ima.active_table.hash_len = md->ima.inactive_table.hash_len;
 409                         md->ima.inactive_table.hash = NULL;
 410                         md->ima.inactive_table.hash_len = 0;
 411                 }
 412
 413                 if (md->ima.inactive_table.device_metadata) {
 414                         md->ima.active_table.device_metadata =
 415                                 md->ima.inactive_table.device_metadata;
 416                         md->ima.active_table.device_metadata_len =
 417                                 md->ima.inactive_table.device_metadata_len;
 418                         md->ima.active_table.num_targets = md->ima.inactive_table.num_targets;
 419                         md->ima.inactive_table.device_metadata = NULL;
 420                         md->ima.inactive_table.device_metadata_len = 0;
 421                         md->ima.inactive_table.num_targets = 0;
 422                 }
 423         }
 424
 425         if (md->ima.active_table.device_metadata) {
 426                 memcpy(device_table_data + l, md->ima.active_table.device_metadata,
 427                        md->ima.active_table.device_metadata_len);
 428                 l += md->ima.active_table.device_metadata_len;
 429
 430                 nodata = false;
 431         }
 432
 433         if (md->ima.active_table.hash) {
 434                 memcpy(device_table_data + l, active, active_len);
 435                 l += active_len;
 436
 437                 memcpy(device_table_data + l, md->ima.active_table.hash,
 438                        md->ima.active_table.hash_len);
 439                 l += md->ima.active_table.hash_len;
 440
 441                 memcpy(device_table_data + l, ";", 1);
 442                 l++;
 443
 444                 nodata = false;
 445         }
 446
 447         if (nodata) {
 448                 r = dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio);
 449                 if (r)
 450                         goto error;
 451
 452                 scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
 453                           "%sname=%s,uuid=%s;device_resume=no_data;",
 454                           DM_IMA_VERSION_STR, dev_name, dev_uuid);
 455                 l = strlen(device_table_data);
 456
 457         }
 458
 459         capacity_len = strlen(capacity_str);
 460         memcpy(device_table_data + l, capacity_str, capacity_len);
 461         l += capacity_len;
 462
 463         dm_ima_measure_data("dm_device_resume", device_table_data, l, noio);
 464
 465         kfree(dev_name);
 466         kfree(dev_uuid);
 467 error:
 468         kfree(capacity_str);
 469         kfree(device_table_data);
 470 }
 471
 472 /*
 473  * Measure IMA data on remove.
 474  */
 475 void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
 476 {
 477         char *device_table_data, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
 478         char active_table_str[] = "active_table_hash=";
 479         char inactive_table_str[] = "inactive_table_hash=";
 480         char device_active_str[] = "device_active_metadata=";
 481         char device_inactive_str[] = "device_inactive_metadata=";
 482         char remove_all_str[] = "remove_all=";
 483         unsigned int active_table_len = strlen(active_table_str);
 484         unsigned int inactive_table_len = strlen(inactive_table_str);
 485         unsigned int device_active_len = strlen(device_active_str);
 486         unsigned int device_inactive_len = strlen(device_inactive_str);
 487         unsigned int remove_all_len = strlen(remove_all_str);
 488         unsigned int capacity_len = 0;
 489         unsigned int l = 0;
 490         bool noio = true;
 491         bool nodata = true;
 492         int r;
 493
 494         device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN*2, GFP_KERNEL, noio);
 495         if (!device_table_data)
 496                 goto exit;
 497
 498         r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
 499         if (r) {
 500                 kfree(device_table_data);
 501                 goto exit;
 502         }
 503
 504         memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
 505         l += md->ima.dm_version_str_len;
 506
 507         if (md->ima.active_table.device_metadata) {
 508                 memcpy(device_table_data + l, device_active_str, device_active_len);
 509                 l += device_active_len;
 510
 511                 memcpy(device_table_data + l, md->ima.active_table.device_metadata,
 512                        md->ima.active_table.device_metadata_len);
 513                 l += md->ima.active_table.device_metadata_len;
 514
 515                 nodata = false;
 516         }
 517
 518         if (md->ima.inactive_table.device_metadata) {
 519                 memcpy(device_table_data + l, device_inactive_str, device_inactive_len);
 520                 l += device_inactive_len;
 521
 522                 memcpy(device_table_data + l, md->ima.inactive_table.device_metadata,
 523                        md->ima.inactive_table.device_metadata_len);
 524                 l += md->ima.inactive_table.device_metadata_len;
 525
 526                 nodata = false;
 527         }
 528
 529         if (md->ima.active_table.hash) {
 530                 memcpy(device_table_data + l, active_table_str, active_table_len);
 531                 l += active_table_len;
 532
 533                 memcpy(device_table_data + l, md->ima.active_table.hash,
 534                            md->ima.active_table.hash_len);
 535                 l += md->ima.active_table.hash_len;
 536
 537                 memcpy(device_table_data + l, ",", 1);
 538                 l++;
 539
 540                 nodata = false;
 541         }
 542
 543         if (md->ima.inactive_table.hash) {
 544                 memcpy(device_table_data + l, inactive_table_str, inactive_table_len);
 545                 l += inactive_table_len;
 546
 547                 memcpy(device_table_data + l, md->ima.inactive_table.hash,
 548                        md->ima.inactive_table.hash_len);
 549                 l += md->ima.inactive_table.hash_len;
 550
 551                 memcpy(device_table_data + l, ",", 1);
 552                 l++;
 553
 554                 nodata = false;
 555         }
 556         /*
 557          * In case both active and inactive tables, and corresponding
 558          * device metadata is cleared/missing - record the name and uuid
 559          * in IMA measurements.
 560          */
 561         if (nodata) {
 562                 if (dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio))
 563                         goto error;
 564
 565                 scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
 566                           "%sname=%s,uuid=%s;device_remove=no_data;",
 567                           DM_IMA_VERSION_STR, dev_name, dev_uuid);
 568                 l = strlen(device_table_data);
 569         }
 570
 571         memcpy(device_table_data + l, remove_all_str, remove_all_len);
 572         l += remove_all_len;
 573         memcpy(device_table_data + l, remove_all ? "y;" : "n;", 2);
 574         l += 2;
 575
 576         capacity_len = strlen(capacity_str);
 577         memcpy(device_table_data + l, capacity_str, capacity_len);
 578         l += capacity_len;
 579
 580         dm_ima_measure_data("dm_device_remove", device_table_data, l, noio);
 581
 582 error:
 583         kfree(device_table_data);
 584         kfree(capacity_str);
 585 exit:
 586         kfree(md->ima.active_table.device_metadata);
 587
 588         if (md->ima.active_table.device_metadata !=
 589             md->ima.inactive_table.device_metadata)
 590                 kfree(md->ima.inactive_table.device_metadata);
 591
 592         kfree(md->ima.active_table.hash);
 593
 594         if (md->ima.active_table.hash != md->ima.inactive_table.hash)
 595                 kfree(md->ima.inactive_table.hash);
 596
 597         dm_ima_reset_data(md);
 598
 599         kfree(dev_name);
 600         kfree(dev_uuid);
 601 }
 602
 603 /*
 604  * Measure ima data on table clear.
 605  */
 606 void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map)
 607 {
 608         unsigned int l = 0, capacity_len = 0;
 609         char *device_table_data = NULL, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
 610         char inactive_str[] = "inactive_table_hash=";
 611         unsigned int inactive_len = strlen(inactive_str);
 612         bool noio = true;
 613         bool nodata = true;
 614         int r;
 615
 616         device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
 617         if (!device_table_data)
 618                 return;
 619
 620         r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
 621         if (r)
 622                 goto error1;
 623
 624         memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
 625         l += md->ima.dm_version_str_len;
 626
 627         if (md->ima.inactive_table.device_metadata_len &&
 628             md->ima.inactive_table.hash_len) {
 629                 memcpy(device_table_data + l, md->ima.inactive_table.device_metadata,
 630                        md->ima.inactive_table.device_metadata_len);
 631                 l += md->ima.inactive_table.device_metadata_len;
 632
 633                 memcpy(device_table_data + l, inactive_str, inactive_len);
 634                 l += inactive_len;
 635
 636                 memcpy(device_table_data + l, md->ima.inactive_table.hash,
 637                            md->ima.inactive_table.hash_len);
 638
 639                 l += md->ima.inactive_table.hash_len;
 640
 641                 memcpy(device_table_data + l, ";", 1);
 642                 l++;
 643
 644                 nodata = false;
 645         }
 646
 647         if (nodata) {
 648                 if (dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio))
 649                         goto error2;
 650
 651                 scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
 652                           "%sname=%s,uuid=%s;table_clear=no_data;",
 653                            DM_IMA_VERSION_STR, dev_name, dev_uuid);
 654                 l = strlen(device_table_data);
 655         }
 656
 657         capacity_len = strlen(capacity_str);
 658         memcpy(device_table_data + l, capacity_str, capacity_len);
 659         l += capacity_len;
 660
 661         dm_ima_measure_data("dm_table_clear", device_table_data, l, noio);
 662
 663         if (new_map) {
 664                 if (md->ima.inactive_table.hash &&
 665                     md->ima.inactive_table.hash != md->ima.active_table.hash)
 666                         kfree(md->ima.inactive_table.hash);
 667
 668                 md->ima.inactive_table.hash = NULL;
 669                 md->ima.inactive_table.hash_len = 0;
 670
 671                 if (md->ima.inactive_table.device_metadata &&
 672                     md->ima.inactive_table.device_metadata != md->ima.active_table.device_metadata)
 673                         kfree(md->ima.inactive_table.device_metadata);
 674
 675                 md->ima.inactive_table.device_metadata = NULL;
 676                 md->ima.inactive_table.device_metadata_len = 0;
 677                 md->ima.inactive_table.num_targets = 0;
 678
 679                 if (md->ima.active_table.hash) {
 680                         md->ima.inactive_table.hash = md->ima.active_table.hash;
 681                         md->ima.inactive_table.hash_len = md->ima.active_table.hash_len;
 682                 }
 683
 684                 if (md->ima.active_table.device_metadata) {
 685                         md->ima.inactive_table.device_metadata =
 686                                 md->ima.active_table.device_metadata;
 687                         md->ima.inactive_table.device_metadata_len =
 688                                 md->ima.active_table.device_metadata_len;
 689                         md->ima.inactive_table.num_targets =
 690                                 md->ima.active_table.num_targets;
 691                 }
 692         }
 693
 694         kfree(dev_name);
 695         kfree(dev_uuid);
 696 error2:
 697         kfree(capacity_str);
 698 error1:
 699         kfree(device_table_data);
 700 }
 701
 702 /*
 703  * Measure IMA data on device rename.
 704  */
 705 void dm_ima_measure_on_device_rename(struct mapped_device *md)
 706 {
 707         char *old_device_data = NULL, *new_device_data = NULL, *combined_device_data = NULL;
 708         char *new_dev_name = NULL, *new_dev_uuid = NULL, *capacity_str = NULL;
 709         bool noio = true;
 710         int r;
 711
 712         if (dm_ima_alloc_and_copy_device_data(md, &new_device_data,
 713                                               md->ima.active_table.num_targets, noio))
 714                 return;
 715
 716         if (dm_ima_alloc_and_copy_name_uuid(md, &new_dev_name, &new_dev_uuid, noio))
 717                 goto error;
 718
 719         combined_device_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN * 2, GFP_KERNEL, noio);
 720         if (!combined_device_data)
 721                 goto error;
 722
 723         r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
 724         if (r)
 725                 goto error;
 726
 727         old_device_data = md->ima.active_table.device_metadata;
 728
 729         md->ima.active_table.device_metadata = new_device_data;
 730         md->ima.active_table.device_metadata_len = strlen(new_device_data);
 731
 732         scnprintf(combined_device_data, DM_IMA_DEVICE_BUF_LEN * 2,
 733                   "%s%snew_name=%s,new_uuid=%s;%s", DM_IMA_VERSION_STR, old_device_data,
 734                   new_dev_name, new_dev_uuid, capacity_str);
 735
 736         dm_ima_measure_data("dm_device_rename", combined_device_data, strlen(combined_device_data),
 737                             noio);
 738
 739         goto exit;
 740
 741 error:
 742         kfree(new_device_data);
 743 exit:
 744         kfree(capacity_str);
 745         kfree(combined_device_data);
 746         kfree(old_device_data);
 747         kfree(new_dev_name);
 748         kfree(new_dev_uuid);
 749 }