drivers/infiniband/core/uverbs_ioctl.c

   1 /*
   2  * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #include <rdma/rdma_user_ioctl.h>
  34 #include <rdma/uverbs_ioctl.h>
  35 #include "rdma_core.h"
  36 #include "uverbs.h"
  37
  38 static int uverbs_process_attr(struct ib_device *ibdev,
  39                                struct ib_ucontext *ucontext,
  40                                const struct ib_uverbs_attr *uattr,
  41                                u16 attr_id,
  42                                const struct uverbs_attr_spec_hash *attr_spec_bucket,
  43                                struct uverbs_attr_bundle_hash *attr_bundle_h,
  44                                struct ib_uverbs_attr __user *uattr_ptr)
  45 {
  46         const struct uverbs_attr_spec *spec;
  47         struct uverbs_attr *e;
  48         const struct uverbs_object_spec *object;
  49         struct uverbs_obj_attr *o_attr;
  50         struct uverbs_attr *elements = attr_bundle_h->attrs;
  51
  52         if (uattr->reserved)
  53                 return -EINVAL;
  54
  55         if (attr_id >= attr_spec_bucket->num_attrs) {
  56                 if (uattr->flags & UVERBS_ATTR_F_MANDATORY)
  57                         return -EINVAL;
  58                 else
  59                         return 0;
  60         }
  61
  62         if (test_bit(attr_id, attr_bundle_h->valid_bitmap))
  63                 return -EINVAL;
  64
  65         spec = &attr_spec_bucket->attrs[attr_id];
  66         e = &elements[attr_id];
  67         e->uattr = uattr_ptr;
  68
  69         switch (spec->type) {
  70         case UVERBS_ATTR_TYPE_PTR_IN:
  71         case UVERBS_ATTR_TYPE_PTR_OUT:
  72                 if (uattr->len < spec->len ||
  73                     (!(spec->flags & UVERBS_ATTR_SPEC_F_MIN_SZ) &&
  74                      uattr->len > spec->len))
  75                         return -EINVAL;
  76
  77                 e->ptr_attr.data = uattr->data;
  78                 e->ptr_attr.len = uattr->len;
  79                 e->ptr_attr.flags = uattr->flags;
  80                 break;
  81
  82         case UVERBS_ATTR_TYPE_IDR:
  83                 if (uattr->data >> 32)
  84                         return -EINVAL;
  85         /* fall through */
  86         case UVERBS_ATTR_TYPE_FD:
  87                 if (uattr->len != 0 || !ucontext || uattr->data > INT_MAX)
  88                         return -EINVAL;
  89
  90                 o_attr = &e->obj_attr;
  91                 object = uverbs_get_object(ibdev, spec->obj.obj_type);
  92                 if (!object)
  93                         return -EINVAL;
  94                 o_attr->type = object->type_attrs;
  95
  96                 o_attr->id = (int)uattr->data;
  97                 o_attr->uobject = uverbs_get_uobject_from_context(
  98                                         o_attr->type,
  99                                         ucontext,
 100                                         spec->obj.access,
 101                                         o_attr->id);
 102
 103                 if (IS_ERR(o_attr->uobject))
 104                         return PTR_ERR(o_attr->uobject);
 105
 106                 if (spec->obj.access == UVERBS_ACCESS_NEW) {
 107                         u64 id = o_attr->uobject->id;
 108
 109                         /* Copy the allocated id to the user-space */
 110                         if (put_user(id, &e->uattr->data)) {
 111                                 uverbs_finalize_object(o_attr->uobject,
 112                                                        UVERBS_ACCESS_NEW,
 113                                                        false);
 114                                 return -EFAULT;
 115                         }
 116                 }
 117
 118                 break;
 119         default:
 120                 return -EOPNOTSUPP;
 121         }
 122
 123         set_bit(attr_id, attr_bundle_h->valid_bitmap);
 124         return 0;
 125 }
 126
 127 static int uverbs_uattrs_process(struct ib_device *ibdev,
 128                                  struct ib_ucontext *ucontext,
 129                                  const struct ib_uverbs_attr *uattrs,
 130                                  size_t num_uattrs,
 131                                  const struct uverbs_method_spec *method,
 132                                  struct uverbs_attr_bundle *attr_bundle,
 133                                  struct ib_uverbs_attr __user *uattr_ptr)
 134 {
 135         size_t i;
 136         int ret = 0;
 137         int num_given_buckets = 0;
 138
 139         for (i = 0; i < num_uattrs; i++) {
 140                 const struct ib_uverbs_attr *uattr = &uattrs[i];
 141                 u16 attr_id = uattr->attr_id;
 142                 struct uverbs_attr_spec_hash *attr_spec_bucket;
 143
 144                 ret = uverbs_ns_idx(&attr_id, method->num_buckets);
 145                 if (ret < 0) {
 146                         if (uattr->flags & UVERBS_ATTR_F_MANDATORY) {
 147                                 uverbs_finalize_objects(attr_bundle,
 148                                                         method->attr_buckets,
 149                                                         num_given_buckets,
 150                                                         false);
 151                                 return ret;
 152                         }
 153                         continue;
 154                 }
 155
 156                 /*
 157                  * ret is the found ns, so increase num_given_buckets if
 158                  * necessary.
 159                  */
 160                 if (ret >= num_given_buckets)
 161                         num_given_buckets = ret + 1;
 162
 163                 attr_spec_bucket = method->attr_buckets[ret];
 164                 ret = uverbs_process_attr(ibdev, ucontext, uattr, attr_id,
 165                                           attr_spec_bucket, &attr_bundle->hash[ret],
 166                                           uattr_ptr++);
 167                 if (ret) {
 168                         uverbs_finalize_objects(attr_bundle,
 169                                                 method->attr_buckets,
 170                                                 num_given_buckets,
 171                                                 false);
 172                         return ret;
 173                 }
 174         }
 175
 176         return num_given_buckets;
 177 }
 178
 179 static int uverbs_validate_kernel_mandatory(const struct uverbs_method_spec *method_spec,
 180                                             struct uverbs_attr_bundle *attr_bundle)
 181 {
 182         unsigned int i;
 183
 184         for (i = 0; i < attr_bundle->num_buckets; i++) {
 185                 struct uverbs_attr_spec_hash *attr_spec_bucket =
 186                         method_spec->attr_buckets[i];
 187
 188                 if (!bitmap_subset(attr_spec_bucket->mandatory_attrs_bitmask,
 189                                    attr_bundle->hash[i].valid_bitmap,
 190                                    attr_spec_bucket->num_attrs))
 191                         return -EINVAL;
 192         }
 193
 194         return 0;
 195 }
 196
 197 static int uverbs_handle_method(struct ib_uverbs_attr __user *uattr_ptr,
 198                                 const struct ib_uverbs_attr *uattrs,
 199                                 size_t num_uattrs,
 200                                 struct ib_device *ibdev,
 201                                 struct ib_uverbs_file *ufile,
 202                                 const struct uverbs_method_spec *method_spec,
 203                                 struct uverbs_attr_bundle *attr_bundle)
 204 {
 205         int ret;
 206         int finalize_ret;
 207         int num_given_buckets;
 208
 209         num_given_buckets = uverbs_uattrs_process(ibdev, ufile->ucontext, uattrs,
 210                                                   num_uattrs, method_spec,
 211                                                   attr_bundle, uattr_ptr);
 212         if (num_given_buckets <= 0)
 213                 return -EINVAL;
 214
 215         attr_bundle->num_buckets = num_given_buckets;
 216         ret = uverbs_validate_kernel_mandatory(method_spec, attr_bundle);
 217         if (ret)
 218                 goto cleanup;
 219
 220         ret = method_spec->handler(ibdev, ufile, attr_bundle);
 221 cleanup:
 222         finalize_ret = uverbs_finalize_objects(attr_bundle,
 223                                                method_spec->attr_buckets,
 224                                                attr_bundle->num_buckets,
 225                                                !ret);
 226
 227         return ret ? ret : finalize_ret;
 228 }
 229
 230 #define UVERBS_OPTIMIZE_USING_STACK_SZ  256
 231 static long ib_uverbs_cmd_verbs(struct ib_device *ib_dev,
 232                                 struct ib_uverbs_file *file,
 233                                 struct ib_uverbs_ioctl_hdr *hdr,
 234                                 void __user *buf)
 235 {
 236         const struct uverbs_object_spec *object_spec;
 237         const struct uverbs_method_spec *method_spec;
 238         long err = 0;
 239         unsigned int i;
 240         struct {
 241                 struct ib_uverbs_attr           *uattrs;
 242                 struct uverbs_attr_bundle       *uverbs_attr_bundle;
 243         } *ctx = NULL;
 244         struct uverbs_attr *curr_attr;
 245         unsigned long *curr_bitmap;
 246         size_t ctx_size;
 247         uintptr_t data[UVERBS_OPTIMIZE_USING_STACK_SZ / sizeof(uintptr_t)];
 248
 249         object_spec = uverbs_get_object(ib_dev, hdr->object_id);
 250         if (!object_spec)
 251                 return -EPROTONOSUPPORT;
 252
 253         method_spec = uverbs_get_method(object_spec, hdr->method_id);
 254         if (!method_spec)
 255                 return -EPROTONOSUPPORT;
 256
 257         if ((method_spec->flags & UVERBS_ACTION_FLAG_CREATE_ROOT) ^ !file->ucontext)
 258                 return -EINVAL;
 259
 260         ctx_size = sizeof(*ctx) +
 261                    sizeof(struct uverbs_attr_bundle) +
 262                    sizeof(struct uverbs_attr_bundle_hash) * method_spec->num_buckets +
 263                    sizeof(*ctx->uattrs) * hdr->num_attrs +
 264                    sizeof(*ctx->uverbs_attr_bundle->hash[0].attrs) *
 265                    method_spec->num_child_attrs +
 266                    sizeof(*ctx->uverbs_attr_bundle->hash[0].valid_bitmap) *
 267                         (method_spec->num_child_attrs / BITS_PER_LONG +
 268                          method_spec->num_buckets);
 269
 270         if (ctx_size <= UVERBS_OPTIMIZE_USING_STACK_SZ)
 271                 ctx = (void *)data;
 272         if (!ctx)
 273                 ctx = kmalloc(ctx_size, GFP_KERNEL);
 274         if (!ctx)
 275                 return -ENOMEM;
 276
 277         ctx->uverbs_attr_bundle = (void *)ctx + sizeof(*ctx);
 278         ctx->uattrs = (void *)(ctx->uverbs_attr_bundle + 1) +
 279                               (sizeof(ctx->uverbs_attr_bundle->hash[0]) *
 280                                method_spec->num_buckets);
 281         curr_attr = (void *)(ctx->uattrs + hdr->num_attrs);
 282         curr_bitmap = (void *)(curr_attr + method_spec->num_child_attrs);
 283
 284         /*
 285          * We just fill the pointers and num_attrs here. The data itself will be
 286          * filled at a later stage (uverbs_process_attr)
 287          */
 288         for (i = 0; i < method_spec->num_buckets; i++) {
 289                 unsigned int curr_num_attrs = method_spec->attr_buckets[i]->num_attrs;
 290
 291                 ctx->uverbs_attr_bundle->hash[i].attrs = curr_attr;
 292                 curr_attr += curr_num_attrs;
 293                 ctx->uverbs_attr_bundle->hash[i].num_attrs = curr_num_attrs;
 294                 ctx->uverbs_attr_bundle->hash[i].valid_bitmap = curr_bitmap;
 295                 bitmap_zero(curr_bitmap, curr_num_attrs);
 296                 curr_bitmap += BITS_TO_LONGS(curr_num_attrs);
 297         }
 298
 299         err = copy_from_user(ctx->uattrs, buf,
 300                              sizeof(*ctx->uattrs) * hdr->num_attrs);
 301         if (err) {
 302                 err = -EFAULT;
 303                 goto out;
 304         }
 305
 306         err = uverbs_handle_method(buf, ctx->uattrs, hdr->num_attrs, ib_dev,
 307                                    file, method_spec, ctx->uverbs_attr_bundle);
 308
 309         /*
 310          * EPROTONOSUPPORT is ONLY to be returned if the ioctl framework can
 311          * not invoke the method because the request is not supported.  No
 312          * other cases should return this code.
 313         */
 314         if (unlikely(err == -EPROTONOSUPPORT)) {
 315                 WARN_ON_ONCE(err == -EPROTONOSUPPORT);
 316                 err = -EINVAL;
 317         }
 318 out:
 319         if (ctx != (void *)data)
 320                 kfree(ctx);
 321         return err;
 322 }
 323
 324 #define IB_UVERBS_MAX_CMD_SZ 4096
 325
 326 long ib_uverbs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 327 {
 328         struct ib_uverbs_file *file = filp->private_data;
 329         struct ib_uverbs_ioctl_hdr __user *user_hdr =
 330                 (struct ib_uverbs_ioctl_hdr __user *)arg;
 331         struct ib_uverbs_ioctl_hdr hdr;
 332         struct ib_device *ib_dev;
 333         int srcu_key;
 334         long err;
 335
 336         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 337         ib_dev = srcu_dereference(file->device->ib_dev,
 338                                   &file->device->disassociate_srcu);
 339         if (!ib_dev) {
 340                 err = -EIO;
 341                 goto out;
 342         }
 343
 344         if (cmd == RDMA_VERBS_IOCTL) {
 345                 err = copy_from_user(&hdr, user_hdr, sizeof(hdr));
 346
 347                 if (err || hdr.length > IB_UVERBS_MAX_CMD_SZ ||
 348                     hdr.length != sizeof(hdr) + hdr.num_attrs * sizeof(struct ib_uverbs_attr)) {
 349                         err = -EINVAL;
 350                         goto out;
 351                 }
 352
 353                 if (hdr.reserved) {
 354                         err = -EPROTONOSUPPORT;
 355                         goto out;
 356                 }
 357
 358                 err = ib_uverbs_cmd_verbs(ib_dev, file, &hdr,
 359                                           (__user void *)arg + sizeof(hdr));
 360         } else {
 361                 err = -ENOIOCTLCMD;
 362         }
 363 out:
 364         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 365
 366         return err;
 367 }