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         spec = &attr_spec_bucket->attrs[attr_id];
  63         e = &elements[attr_id];
  64         e->uattr = uattr_ptr;
  65
  66         switch (spec->type) {
  67         case UVERBS_ATTR_TYPE_PTR_IN:
  68         case UVERBS_ATTR_TYPE_PTR_OUT:
  69                 if (uattr->len < spec->len ||
  70                     (!(spec->flags & UVERBS_ATTR_SPEC_F_MIN_SZ) &&
  71                      uattr->len > spec->len))
  72                         return -EINVAL;
  73
  74                 e->ptr_attr.data = uattr->data;
  75                 e->ptr_attr.len = uattr->len;
  76                 e->ptr_attr.flags = uattr->flags;
  77                 break;
  78
  79         case UVERBS_ATTR_TYPE_IDR:
  80                 if (uattr->data >> 32)
  81                         return -EINVAL;
  82         /* fall through */
  83         case UVERBS_ATTR_TYPE_FD:
  84                 if (uattr->len != 0 || !ucontext || uattr->data > INT_MAX)
  85                         return -EINVAL;
  86
  87                 o_attr = &e->obj_attr;
  88                 object = uverbs_get_object(ibdev, spec->obj.obj_type);
  89                 if (!object)
  90                         return -EINVAL;
  91                 o_attr->type = object->type_attrs;
  92
  93                 o_attr->id = (int)uattr->data;
  94                 o_attr->uobject = uverbs_get_uobject_from_context(
  95                                         o_attr->type,
  96                                         ucontext,
  97                                         spec->obj.access,
  98                                         o_attr->id);
  99
 100                 if (IS_ERR(o_attr->uobject))
 101                         return PTR_ERR(o_attr->uobject);
 102
 103                 if (spec->obj.access == UVERBS_ACCESS_NEW) {
 104                         u64 id = o_attr->uobject->id;
 105
 106                         /* Copy the allocated id to the user-space */
 107                         if (put_user(id, &e->uattr->data)) {
 108                                 uverbs_finalize_object(o_attr->uobject,
 109                                                        UVERBS_ACCESS_NEW,
 110                                                        false);
 111                                 return -EFAULT;
 112                         }
 113                 }
 114
 115                 break;
 116         default:
 117                 return -EOPNOTSUPP;
 118         }
 119
 120         set_bit(attr_id, attr_bundle_h->valid_bitmap);
 121         return 0;
 122 }
 123
 124 static int uverbs_uattrs_process(struct ib_device *ibdev,
 125                                  struct ib_ucontext *ucontext,
 126                                  const struct ib_uverbs_attr *uattrs,
 127                                  size_t num_uattrs,
 128                                  const struct uverbs_method_spec *method,
 129                                  struct uverbs_attr_bundle *attr_bundle,
 130                                  struct ib_uverbs_attr __user *uattr_ptr)
 131 {
 132         size_t i;
 133         int ret = 0;
 134         int num_given_buckets = 0;
 135
 136         for (i = 0; i < num_uattrs; i++) {
 137                 const struct ib_uverbs_attr *uattr = &uattrs[i];
 138                 u16 attr_id = uattr->attr_id;
 139                 struct uverbs_attr_spec_hash *attr_spec_bucket;
 140
 141                 ret = uverbs_ns_idx(&attr_id, method->num_buckets);
 142                 if (ret < 0) {
 143                         if (uattr->flags & UVERBS_ATTR_F_MANDATORY) {
 144                                 uverbs_finalize_objects(attr_bundle,
 145                                                         method->attr_buckets,
 146                                                         num_given_buckets,
 147                                                         false);
 148                                 return ret;
 149                         }
 150                         continue;
 151                 }
 152
 153                 /*
 154                  * ret is the found ns, so increase num_given_buckets if
 155                  * necessary.
 156                  */
 157                 if (ret >= num_given_buckets)
 158                         num_given_buckets = ret + 1;
 159
 160                 attr_spec_bucket = method->attr_buckets[ret];
 161                 ret = uverbs_process_attr(ibdev, ucontext, uattr, attr_id,
 162                                           attr_spec_bucket, &attr_bundle->hash[ret],
 163                                           uattr_ptr++);
 164                 if (ret) {
 165                         uverbs_finalize_objects(attr_bundle,
 166                                                 method->attr_buckets,
 167                                                 num_given_buckets,
 168                                                 false);
 169                         return ret;
 170                 }
 171         }
 172
 173         return num_given_buckets;
 174 }
 175
 176 static int uverbs_validate_kernel_mandatory(const struct uverbs_method_spec *method_spec,
 177                                             struct uverbs_attr_bundle *attr_bundle)
 178 {
 179         unsigned int i;
 180
 181         for (i = 0; i < attr_bundle->num_buckets; i++) {
 182                 struct uverbs_attr_spec_hash *attr_spec_bucket =
 183                         method_spec->attr_buckets[i];
 184
 185                 if (!bitmap_subset(attr_spec_bucket->mandatory_attrs_bitmask,
 186                                    attr_bundle->hash[i].valid_bitmap,
 187                                    attr_spec_bucket->num_attrs))
 188                         return -EINVAL;
 189         }
 190
 191         return 0;
 192 }
 193
 194 static int uverbs_handle_method(struct ib_uverbs_attr __user *uattr_ptr,
 195                                 const struct ib_uverbs_attr *uattrs,
 196                                 size_t num_uattrs,
 197                                 struct ib_device *ibdev,
 198                                 struct ib_uverbs_file *ufile,
 199                                 const struct uverbs_method_spec *method_spec,
 200                                 struct uverbs_attr_bundle *attr_bundle)
 201 {
 202         int ret;
 203         int finalize_ret;
 204         int num_given_buckets;
 205
 206         num_given_buckets = uverbs_uattrs_process(ibdev, ufile->ucontext, uattrs,
 207                                                   num_uattrs, method_spec,
 208                                                   attr_bundle, uattr_ptr);
 209         if (num_given_buckets <= 0)
 210                 return -EINVAL;
 211
 212         attr_bundle->num_buckets = num_given_buckets;
 213         ret = uverbs_validate_kernel_mandatory(method_spec, attr_bundle);
 214         if (ret)
 215                 goto cleanup;
 216
 217         ret = method_spec->handler(ibdev, ufile, attr_bundle);
 218 cleanup:
 219         finalize_ret = uverbs_finalize_objects(attr_bundle,
 220                                                method_spec->attr_buckets,
 221                                                attr_bundle->num_buckets,
 222                                                !ret);
 223
 224         return ret ? ret : finalize_ret;
 225 }
 226
 227 #define UVERBS_OPTIMIZE_USING_STACK_SZ  256
 228 static long ib_uverbs_cmd_verbs(struct ib_device *ib_dev,
 229                                 struct ib_uverbs_file *file,
 230                                 struct ib_uverbs_ioctl_hdr *hdr,
 231                                 void __user *buf)
 232 {
 233         const struct uverbs_object_spec *object_spec;
 234         const struct uverbs_method_spec *method_spec;
 235         long err = 0;
 236         unsigned int i;
 237         struct {
 238                 struct ib_uverbs_attr           *uattrs;
 239                 struct uverbs_attr_bundle       *uverbs_attr_bundle;
 240         } *ctx = NULL;
 241         struct uverbs_attr *curr_attr;
 242         unsigned long *curr_bitmap;
 243         size_t ctx_size;
 244         uintptr_t data[UVERBS_OPTIMIZE_USING_STACK_SZ / sizeof(uintptr_t)];
 245
 246         object_spec = uverbs_get_object(ib_dev, hdr->object_id);
 247         if (!object_spec)
 248                 return -EPROTONOSUPPORT;
 249
 250         method_spec = uverbs_get_method(object_spec, hdr->method_id);
 251         if (!method_spec)
 252                 return -EPROTONOSUPPORT;
 253
 254         if ((method_spec->flags & UVERBS_ACTION_FLAG_CREATE_ROOT) ^ !file->ucontext)
 255                 return -EINVAL;
 256
 257         ctx_size = sizeof(*ctx) +
 258                    sizeof(struct uverbs_attr_bundle) +
 259                    sizeof(struct uverbs_attr_bundle_hash) * method_spec->num_buckets +
 260                    sizeof(*ctx->uattrs) * hdr->num_attrs +
 261                    sizeof(*ctx->uverbs_attr_bundle->hash[0].attrs) *
 262                    method_spec->num_child_attrs +
 263                    sizeof(*ctx->uverbs_attr_bundle->hash[0].valid_bitmap) *
 264                         (method_spec->num_child_attrs / BITS_PER_LONG +
 265                          method_spec->num_buckets);
 266
 267         if (ctx_size <= UVERBS_OPTIMIZE_USING_STACK_SZ)
 268                 ctx = (void *)data;
 269         if (!ctx)
 270                 ctx = kmalloc(ctx_size, GFP_KERNEL);
 271         if (!ctx)
 272                 return -ENOMEM;
 273
 274         ctx->uverbs_attr_bundle = (void *)ctx + sizeof(*ctx);
 275         ctx->uattrs = (void *)(ctx->uverbs_attr_bundle + 1) +
 276                               (sizeof(ctx->uverbs_attr_bundle->hash[0]) *
 277                                method_spec->num_buckets);
 278         curr_attr = (void *)(ctx->uattrs + hdr->num_attrs);
 279         curr_bitmap = (void *)(curr_attr + method_spec->num_child_attrs);
 280
 281         /*
 282          * We just fill the pointers and num_attrs here. The data itself will be
 283          * filled at a later stage (uverbs_process_attr)
 284          */
 285         for (i = 0; i < method_spec->num_buckets; i++) {
 286                 unsigned int curr_num_attrs = method_spec->attr_buckets[i]->num_attrs;
 287
 288                 ctx->uverbs_attr_bundle->hash[i].attrs = curr_attr;
 289                 curr_attr += curr_num_attrs;
 290                 ctx->uverbs_attr_bundle->hash[i].num_attrs = curr_num_attrs;
 291                 ctx->uverbs_attr_bundle->hash[i].valid_bitmap = curr_bitmap;
 292                 bitmap_zero(curr_bitmap, curr_num_attrs);
 293                 curr_bitmap += BITS_TO_LONGS(curr_num_attrs);
 294         }
 295
 296         err = copy_from_user(ctx->uattrs, buf,
 297                              sizeof(*ctx->uattrs) * hdr->num_attrs);
 298         if (err) {
 299                 err = -EFAULT;
 300                 goto out;
 301         }
 302
 303         err = uverbs_handle_method(buf, ctx->uattrs, hdr->num_attrs, ib_dev,
 304                                    file, method_spec, ctx->uverbs_attr_bundle);
 305
 306         /*
 307          * EPROTONOSUPPORT is ONLY to be returned if the ioctl framework can
 308          * not invoke the method because the request is not supported.  No
 309          * other cases should return this code.
 310         */
 311         if (unlikely(err == -EPROTONOSUPPORT)) {
 312                 WARN_ON_ONCE(err == -EPROTONOSUPPORT);
 313                 err = -EINVAL;
 314         }
 315 out:
 316         if (ctx != (void *)data)
 317                 kfree(ctx);
 318         return err;
 319 }
 320
 321 #define IB_UVERBS_MAX_CMD_SZ 4096
 322
 323 long ib_uverbs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 324 {
 325         struct ib_uverbs_file *file = filp->private_data;
 326         struct ib_uverbs_ioctl_hdr __user *user_hdr =
 327                 (struct ib_uverbs_ioctl_hdr __user *)arg;
 328         struct ib_uverbs_ioctl_hdr hdr;
 329         struct ib_device *ib_dev;
 330         int srcu_key;
 331         long err;
 332
 333         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 334         ib_dev = srcu_dereference(file->device->ib_dev,
 335                                   &file->device->disassociate_srcu);
 336         if (!ib_dev) {
 337                 err = -EIO;
 338                 goto out;
 339         }
 340
 341         if (cmd == RDMA_VERBS_IOCTL) {
 342                 err = copy_from_user(&hdr, user_hdr, sizeof(hdr));
 343
 344                 if (err || hdr.length > IB_UVERBS_MAX_CMD_SZ ||
 345                     hdr.length != sizeof(hdr) + hdr.num_attrs * sizeof(struct ib_uverbs_attr)) {
 346                         err = -EINVAL;
 347                         goto out;
 348                 }
 349
 350                 if (hdr.reserved) {
 351                         err = -EPROTONOSUPPORT;
 352                         goto out;
 353                 }
 354
 355                 err = ib_uverbs_cmd_verbs(ib_dev, file, &hdr,
 356                                           (__user void *)arg + sizeof(hdr));
 357         } else {
 358                 err = -ENOIOCTLCMD;
 359         }
 360 out:
 361         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 362
 363         return err;
 364 }