src/intel/tools/intel_sanitize_gpu.c

   1 /*
   2  * Copyright © 2015-2018 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  */
  23
  24 #undef _FILE_OFFSET_BITS /* prevent #define open open64 */
  25
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <stdint.h>
  30 #include <stdarg.h>
  31 #include <fcntl.h>
  32 #include <unistd.h>
  33 #include <sys/ioctl.h>
  34 #include <sys/stat.h>
  35 #include <sys/mman.h>
  36 #include <sys/sysmacros.h>
  37 #include <dlfcn.h>
  38 #include <pthread.h>
  39 #include <i915_drm.h>
  40
  41 #include "util/hash_table.h"
  42
  43 #define INTEL_LOG_TAG "INTEL-SANITIZE-GPU"
  44 #include "common/intel_log.h"
  45 #include "common/gen_clflush.h"
  46
  47 static int (*libc_open)(const char *pathname, int flags, mode_t mode);
  48 static int (*libc_close)(int fd);
  49 static int (*libc_ioctl)(int fd, unsigned long request, void *argp);
  50 static int (*libc_fcntl)(int fd, int cmd, int param);
  51
  52 #define DRM_MAJOR 226
  53
  54 /* TODO: we want to make sure that the padding forces
  55  * the BO to take another page on the (PP)GTT; 4KB
  56  * may or may not be the page size for the BO. Indeed,
  57  * depending on GPU, kernel version and GEM size, the
  58  * page size can be one of 4KB, 64KB or 2M.
  59  */
  60 #define PADDING_SIZE 4096
  61
  62 struct refcnt_hash_table {
  63    struct hash_table *t;
  64    int refcnt;
  65 };
  66
  67 pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
  68 #define MUTEX_LOCK() do {                        \
  69    if (unlikely(pthread_mutex_lock(&mutex))) {   \
  70       intel_loge("mutex_lock failed");           \
  71       abort();                                   \
  72    }                                             \
  73 } while (0)
  74 #define MUTEX_UNLOCK() do {                      \
  75    if (unlikely(pthread_mutex_unlock(&mutex))) { \
  76       intel_loge("mutex_unlock failed");         \
  77       abort();                                   \
  78    }                                             \
  79 } while (0)
  80
  81 static struct hash_table *fds_to_bo_sizes = NULL;
  82
  83 static inline struct hash_table*
  84 bo_size_table(int fd)
  85 {
  86    struct hash_entry *e = _mesa_hash_table_search(fds_to_bo_sizes,
  87                                                   (void*)(uintptr_t)fd);
  88    return e ? ((struct refcnt_hash_table*)e->data)->t : NULL;
  89 }
  90
  91 static inline uint64_t
  92 bo_size(int fd, uint32_t handle)
  93 {
  94    struct hash_table *t = bo_size_table(fd);
  95    if (!t)
  96       return UINT64_MAX;
  97    struct hash_entry *e = _mesa_hash_table_search(t, (void*)(uintptr_t)handle);
  98    return e ? (uint64_t)e->data : UINT64_MAX;
  99 }
 100
 101 static inline bool
 102 is_drm_fd(int fd)
 103 {
 104    return !!bo_size_table(fd);
 105 }
 106
 107 static inline void
 108 add_drm_fd(int fd)
 109 {
 110    struct refcnt_hash_table *r = malloc(sizeof(*r));
 111    r->refcnt = 1;
 112    r->t = _mesa_hash_table_create(NULL, _mesa_hash_pointer,
 113                                   _mesa_key_pointer_equal);
 114    _mesa_hash_table_insert(fds_to_bo_sizes, (void*)(uintptr_t)fd,
 115                            (void*)(uintptr_t)r);
 116 }
 117
 118 static inline void
 119 dup_drm_fd(int old_fd, int new_fd)
 120 {
 121    struct hash_entry *e = _mesa_hash_table_search(fds_to_bo_sizes,
 122                                                   (void*)(uintptr_t)old_fd);
 123    struct refcnt_hash_table *r = e->data;
 124    r->refcnt++;
 125    _mesa_hash_table_insert(fds_to_bo_sizes, (void*)(uintptr_t)new_fd,
 126                            (void*)(uintptr_t)r);
 127 }
 128
 129 static inline void
 130 del_drm_fd(int fd)
 131 {
 132    struct hash_entry *e = _mesa_hash_table_search(fds_to_bo_sizes,
 133                                                   (void*)(uintptr_t)fd);
 134    struct refcnt_hash_table *r = e->data;
 135    if (!--r->refcnt) {
 136       _mesa_hash_table_remove(fds_to_bo_sizes, e);
 137       _mesa_hash_table_destroy(r->t, NULL);
 138       free(r);
 139    }
 140 }
 141
 142 /* Our goal is not to have noise good enough for cryto,
 143  * but instead values that are unique-ish enough that
 144  * it is incredibly unlikely that a buffer overwrite
 145  * will produce the exact same values.
 146  */
 147 static uint8_t
 148 next_noise_value(uint8_t prev_noise)
 149 {
 150    uint32_t v = prev_noise;
 151    return (v * 103u + 227u) & 0xFF;
 152 }
 153
 154 static void
 155 fill_noise_buffer(uint8_t *dst, uint8_t start, uint32_t length)
 156 {
 157    for(uint32_t i = 0; i < length; ++i) {
 158       dst[i] = start;
 159       start = next_noise_value(start);
 160    }
 161 }
 162
 163 static bool
 164 padding_is_good(int fd, uint32_t handle)
 165 {
 166    struct drm_i915_gem_mmap mmap_arg = {
 167       .handle = handle,
 168       .offset = bo_size(fd, handle),
 169       .size = PADDING_SIZE,
 170       .flags = 0,
 171    };
 172
 173    /* Unknown bo, maybe prime or userptr. Ignore */
 174    if (mmap_arg.offset == UINT64_MAX)
 175       return true;
 176
 177    uint8_t *mapped;
 178    int ret;
 179    uint8_t expected_value;
 180
 181    ret = libc_ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &mmap_arg);
 182    if (ret != 0) {
 183       intel_logd("Unable to map buffer %d for pad checking.", handle);
 184       return false;
 185    }
 186
 187    mapped = (uint8_t*) (uintptr_t) mmap_arg.addr_ptr;
 188    /* bah-humbug, we need to see the latest contents and
 189     * if the bo is not cache coherent we likely need to
 190     * invalidate the cache lines to get it.
 191     */
 192    gen_invalidate_range(mapped, PADDING_SIZE);
 193
 194    expected_value = handle & 0xFF;
 195    for (uint32_t i = 0; i < PADDING_SIZE; ++i) {
 196       if (expected_value != mapped[i]) {
 197          munmap(mapped, PADDING_SIZE);
 198          return false;
 199       }
 200       expected_value = next_noise_value(expected_value);
 201    }
 202    munmap(mapped, PADDING_SIZE);
 203
 204    return true;
 205 }
 206
 207 static int
 208 create_with_padding(int fd, struct drm_i915_gem_create *create)
 209 {
 210    create->size += PADDING_SIZE;
 211    int ret = libc_ioctl(fd, DRM_IOCTL_I915_GEM_CREATE, create);
 212    create->size -= PADDING_SIZE;
 213
 214    if (ret != 0)
 215       return ret;
 216
 217    uint8_t *noise_values;
 218    struct drm_i915_gem_mmap mmap_arg = {
 219       .handle = create->handle,
 220       .offset = create->size,
 221       .size = PADDING_SIZE,
 222       .flags = 0,
 223    };
 224
 225    ret = libc_ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &mmap_arg);
 226    if (ret != 0)
 227       return 0;
 228
 229    noise_values = (uint8_t*) (uintptr_t) mmap_arg.addr_ptr;
 230    fill_noise_buffer(noise_values, create->handle & 0xFF,
 231                      PADDING_SIZE);
 232    munmap(noise_values, PADDING_SIZE);
 233
 234    _mesa_hash_table_insert(bo_size_table(fd), (void*)(uintptr_t)create->handle,
 235                            (void*)(uintptr_t)create->size);
 236
 237    return 0;
 238 }
 239
 240 static int
 241 exec_and_check_padding(int fd, unsigned long request,
 242                        struct drm_i915_gem_execbuffer2 *exec)
 243 {
 244    int ret = libc_ioctl(fd, request, exec);
 245    if (ret != 0)
 246       return ret;
 247
 248    struct drm_i915_gem_exec_object2 *objects =
 249       (void*)(uintptr_t)exec->buffers_ptr;
 250    uint32_t batch_bo = exec->flags & I915_EXEC_BATCH_FIRST ? objects[0].handle :
 251       objects[exec->buffer_count - 1].handle;
 252
 253    struct drm_i915_gem_wait wait = {
 254       .bo_handle = batch_bo,
 255       .timeout_ns = -1,
 256    };
 257    ret = libc_ioctl(fd, DRM_IOCTL_I915_GEM_WAIT, &wait);
 258    if (ret != 0)
 259       return ret;
 260
 261    bool detected_out_of_bounds_write = false;
 262
 263    for (int i = 0; i < exec->buffer_count; i++) {
 264       uint32_t handle = objects[i].handle;
 265
 266       if (!padding_is_good(fd, handle)) {
 267          detected_out_of_bounds_write = true;
 268          intel_loge("Detected buffer out-of-bounds write in bo %d", handle);
 269       }
 270    }
 271
 272    if (unlikely(detected_out_of_bounds_write)) {
 273       abort();
 274    }
 275
 276    return 0;
 277 }
 278
 279 static int
 280 gem_close(int fd, struct drm_gem_close *close)
 281 {
 282    int ret = libc_ioctl(fd, DRM_IOCTL_GEM_CLOSE, close);
 283    if (ret != 0)
 284       return ret;
 285
 286    struct hash_table *t = bo_size_table(fd);
 287    struct hash_entry *e =
 288       _mesa_hash_table_search(t, (void*)(uintptr_t)close->handle);
 289
 290    if (e)
 291       _mesa_hash_table_remove(t, e);
 292
 293    return 0;
 294 }
 295
 296 static bool
 297 is_i915(int fd) {
 298    struct stat stat;
 299    if (fstat(fd, &stat))
 300       return false;
 301
 302    if (!S_ISCHR(stat.st_mode) || major(stat.st_rdev) != DRM_MAJOR)
 303       return false;
 304
 305    char name[5] = "";
 306    drm_version_t version = {
 307       .name = name,
 308       .name_len = sizeof(name) - 1,
 309    };
 310    if (libc_ioctl(fd, DRM_IOCTL_VERSION, &version))
 311       return false;
 312
 313    return strcmp("i915", name) == 0;
 314 }
 315
 316 __attribute__ ((visibility ("default"))) int
 317 open(const char *path, int flags, ...)
 318 {
 319    va_list args;
 320    mode_t mode;
 321
 322    va_start(args, flags);
 323    mode = va_arg(args, int);
 324    va_end(args);
 325
 326    int fd = libc_open(path, flags, mode);
 327
 328    MUTEX_LOCK();
 329
 330    if (fd >= 0 && is_i915(fd))
 331       add_drm_fd(fd);
 332
 333    MUTEX_UNLOCK();
 334
 335    return fd;
 336 }
 337
 338 __attribute__ ((visibility ("default"), alias ("open"))) int
 339 open64(const char *path, int flags, ...);
 340
 341 __attribute__ ((visibility ("default"))) int
 342 close(int fd)
 343 {
 344    MUTEX_LOCK();
 345
 346    if (is_drm_fd(fd))
 347       del_drm_fd(fd);
 348
 349    MUTEX_UNLOCK();
 350
 351    return libc_close(fd);
 352 }
 353
 354 __attribute__ ((visibility ("default"))) int
 355 fcntl(int fd, int cmd, ...)
 356 {
 357    va_list args;
 358    int param;
 359
 360    va_start(args, cmd);
 361    param = va_arg(args, int);
 362    va_end(args);
 363
 364    int res = libc_fcntl(fd, cmd, param);
 365
 366    MUTEX_LOCK();
 367
 368    if (is_drm_fd(fd) && cmd == F_DUPFD_CLOEXEC)
 369       dup_drm_fd(fd, res);
 370
 371    MUTEX_UNLOCK();
 372
 373    return res;
 374 }
 375
 376 __attribute__ ((visibility ("default"))) int
 377 ioctl(int fd, unsigned long request, ...)
 378 {
 379    int res;
 380    va_list args;
 381    void *argp;
 382
 383    MUTEX_LOCK();
 384
 385    va_start(args, request);
 386    argp = va_arg(args, void *);
 387    va_end(args);
 388
 389    if (_IOC_TYPE(request) == DRM_IOCTL_BASE && !is_drm_fd(fd) && is_i915(fd)) {
 390       intel_loge("missed drm fd %d", fd);
 391       add_drm_fd(fd);
 392    }
 393
 394    if (is_drm_fd(fd)) {
 395       switch (request) {
 396       case DRM_IOCTL_GEM_CLOSE:
 397          res = gem_close(fd, (struct drm_gem_close*)argp);
 398          goto out;
 399
 400       case DRM_IOCTL_I915_GEM_CREATE:
 401          res = create_with_padding(fd, (struct drm_i915_gem_create*)argp);
 402          goto out;
 403
 404       case DRM_IOCTL_I915_GEM_EXECBUFFER2:
 405       case DRM_IOCTL_I915_GEM_EXECBUFFER2_WR:
 406          res = exec_and_check_padding(fd, request,
 407                                       (struct drm_i915_gem_execbuffer2*)argp);
 408          goto out;
 409
 410       default:
 411          break;
 412       }
 413    }
 414    res = libc_ioctl(fd, request, argp);
 415
 416  out:
 417    MUTEX_UNLOCK();
 418    return res;
 419 }
 420
 421 static void __attribute__ ((constructor))
 422 init(void)
 423 {
 424    fds_to_bo_sizes = _mesa_hash_table_create(NULL, _mesa_hash_pointer,
 425                                              _mesa_key_pointer_equal);
 426    libc_open = dlsym(RTLD_NEXT, "open");
 427    libc_close = dlsym(RTLD_NEXT, "close");
 428    libc_fcntl = dlsym(RTLD_NEXT, "fcntl");
 429    libc_ioctl = dlsym(RTLD_NEXT, "ioctl");
 430 }