| 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 2 | /* |
| 3 | * Copyright (C) 2006 IBM Corporation |
| 4 | * |
| 5 | * Author: Serge Hallyn <serue@us.ibm.com> |
| 6 | * |
| 7 | * Jun 2006 - namespaces support |
| 8 | * OpenVZ, SWsoft Inc. |
| 9 | * Pavel Emelianov <xemul@openvz.org> |
| 10 | */ |
| 11 | |
| 12 | #include <linux/slab.h> |
| 13 | #include <linux/export.h> |
| 14 | #include <linux/nsproxy.h> |
| 15 | #include <linux/init_task.h> |
| 16 | #include <linux/mnt_namespace.h> |
| 17 | #include <linux/utsname.h> |
| 18 | #include <linux/pid_namespace.h> |
| 19 | #include <net/net_namespace.h> |
| 20 | #include <linux/ipc_namespace.h> |
| 21 | #include <linux/time_namespace.h> |
| 22 | #include <linux/fs_struct.h> |
| 23 | #include <linux/proc_fs.h> |
| 24 | #include <linux/proc_ns.h> |
| 25 | #include <linux/file.h> |
| 26 | #include <linux/syscalls.h> |
| 27 | #include <linux/cgroup.h> |
| 28 | #include <linux/perf_event.h> |
| 29 | |
| 30 | static struct kmem_cache *nsproxy_cachep; |
| 31 | |
| 32 | struct nsproxy init_nsproxy = { |
| 33 | .count = ATOMIC_INIT(1), |
| 34 | .uts_ns = &init_uts_ns, |
| 35 | #if defined(CONFIG_POSIX_MQUEUE) || defined(CONFIG_SYSVIPC) |
| 36 | .ipc_ns = &init_ipc_ns, |
| 37 | #endif |
| 38 | .mnt_ns = NULL, |
| 39 | .pid_ns_for_children = &init_pid_ns, |
| 40 | #ifdef CONFIG_NET |
| 41 | .net_ns = &init_net, |
| 42 | #endif |
| 43 | #ifdef CONFIG_CGROUPS |
| 44 | .cgroup_ns = &init_cgroup_ns, |
| 45 | #endif |
| 46 | #ifdef CONFIG_TIME_NS |
| 47 | .time_ns = &init_time_ns, |
| 48 | .time_ns_for_children = &init_time_ns, |
| 49 | #endif |
| 50 | }; |
| 51 | |
| 52 | static inline struct nsproxy *create_nsproxy(void) |
| 53 | { |
| 54 | struct nsproxy *nsproxy; |
| 55 | |
| 56 | nsproxy = kmem_cache_alloc(nsproxy_cachep, GFP_KERNEL); |
| 57 | if (nsproxy) |
| 58 | atomic_set(&nsproxy->count, 1); |
| 59 | return nsproxy; |
| 60 | } |
| 61 | |
| 62 | /* |
| 63 | * Create new nsproxy and all of its the associated namespaces. |
| 64 | * Return the newly created nsproxy. Do not attach this to the task, |
| 65 | * leave it to the caller to do proper locking and attach it to task. |
| 66 | */ |
| 67 | static struct nsproxy *create_new_namespaces(unsigned long flags, |
| 68 | struct task_struct *tsk, struct user_namespace *user_ns, |
| 69 | struct fs_struct *new_fs) |
| 70 | { |
| 71 | struct nsproxy *new_nsp; |
| 72 | int err; |
| 73 | |
| 74 | new_nsp = create_nsproxy(); |
| 75 | if (!new_nsp) |
| 76 | return ERR_PTR(-ENOMEM); |
| 77 | |
| 78 | new_nsp->mnt_ns = copy_mnt_ns(flags, tsk->nsproxy->mnt_ns, user_ns, new_fs); |
| 79 | if (IS_ERR(new_nsp->mnt_ns)) { |
| 80 | err = PTR_ERR(new_nsp->mnt_ns); |
| 81 | goto out_ns; |
| 82 | } |
| 83 | |
| 84 | new_nsp->uts_ns = copy_utsname(flags, user_ns, tsk->nsproxy->uts_ns); |
| 85 | if (IS_ERR(new_nsp->uts_ns)) { |
| 86 | err = PTR_ERR(new_nsp->uts_ns); |
| 87 | goto out_uts; |
| 88 | } |
| 89 | |
| 90 | new_nsp->ipc_ns = copy_ipcs(flags, user_ns, tsk->nsproxy->ipc_ns); |
| 91 | if (IS_ERR(new_nsp->ipc_ns)) { |
| 92 | err = PTR_ERR(new_nsp->ipc_ns); |
| 93 | goto out_ipc; |
| 94 | } |
| 95 | |
| 96 | new_nsp->pid_ns_for_children = |
| 97 | copy_pid_ns(flags, user_ns, tsk->nsproxy->pid_ns_for_children); |
| 98 | if (IS_ERR(new_nsp->pid_ns_for_children)) { |
| 99 | err = PTR_ERR(new_nsp->pid_ns_for_children); |
| 100 | goto out_pid; |
| 101 | } |
| 102 | |
| 103 | new_nsp->cgroup_ns = copy_cgroup_ns(flags, user_ns, |
| 104 | tsk->nsproxy->cgroup_ns); |
| 105 | if (IS_ERR(new_nsp->cgroup_ns)) { |
| 106 | err = PTR_ERR(new_nsp->cgroup_ns); |
| 107 | goto out_cgroup; |
| 108 | } |
| 109 | |
| 110 | new_nsp->net_ns = copy_net_ns(flags, user_ns, tsk->nsproxy->net_ns); |
| 111 | if (IS_ERR(new_nsp->net_ns)) { |
| 112 | err = PTR_ERR(new_nsp->net_ns); |
| 113 | goto out_net; |
| 114 | } |
| 115 | |
| 116 | new_nsp->time_ns_for_children = copy_time_ns(flags, user_ns, |
| 117 | tsk->nsproxy->time_ns_for_children); |
| 118 | if (IS_ERR(new_nsp->time_ns_for_children)) { |
| 119 | err = PTR_ERR(new_nsp->time_ns_for_children); |
| 120 | goto out_time; |
| 121 | } |
| 122 | new_nsp->time_ns = get_time_ns(tsk->nsproxy->time_ns); |
| 123 | |
| 124 | return new_nsp; |
| 125 | |
| 126 | out_time: |
| 127 | put_net(new_nsp->net_ns); |
| 128 | out_net: |
| 129 | put_cgroup_ns(new_nsp->cgroup_ns); |
| 130 | out_cgroup: |
| 131 | if (new_nsp->pid_ns_for_children) |
| 132 | put_pid_ns(new_nsp->pid_ns_for_children); |
| 133 | out_pid: |
| 134 | if (new_nsp->ipc_ns) |
| 135 | put_ipc_ns(new_nsp->ipc_ns); |
| 136 | out_ipc: |
| 137 | if (new_nsp->uts_ns) |
| 138 | put_uts_ns(new_nsp->uts_ns); |
| 139 | out_uts: |
| 140 | if (new_nsp->mnt_ns) |
| 141 | put_mnt_ns(new_nsp->mnt_ns); |
| 142 | out_ns: |
| 143 | kmem_cache_free(nsproxy_cachep, new_nsp); |
| 144 | return ERR_PTR(err); |
| 145 | } |
| 146 | |
| 147 | /* |
| 148 | * called from clone. This now handles copy for nsproxy and all |
| 149 | * namespaces therein. |
| 150 | */ |
| 151 | int copy_namespaces(unsigned long flags, struct task_struct *tsk) |
| 152 | { |
| 153 | struct nsproxy *old_ns = tsk->nsproxy; |
| 154 | struct user_namespace *user_ns = task_cred_xxx(tsk, user_ns); |
| 155 | struct nsproxy *new_ns; |
| 156 | |
| 157 | if (likely(!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | |
| 158 | CLONE_NEWPID | CLONE_NEWNET | |
| 159 | CLONE_NEWCGROUP | CLONE_NEWTIME)))) { |
| 160 | if ((flags & CLONE_VM) || |
| 161 | likely(old_ns->time_ns_for_children == old_ns->time_ns)) { |
| 162 | get_nsproxy(old_ns); |
| 163 | return 0; |
| 164 | } |
| 165 | } else if (!ns_capable(user_ns, CAP_SYS_ADMIN)) |
| 166 | return -EPERM; |
| 167 | |
| 168 | /* |
| 169 | * CLONE_NEWIPC must detach from the undolist: after switching |
| 170 | * to a new ipc namespace, the semaphore arrays from the old |
| 171 | * namespace are unreachable. In clone parlance, CLONE_SYSVSEM |
| 172 | * means share undolist with parent, so we must forbid using |
| 173 | * it along with CLONE_NEWIPC. |
| 174 | */ |
| 175 | if ((flags & (CLONE_NEWIPC | CLONE_SYSVSEM)) == |
| 176 | (CLONE_NEWIPC | CLONE_SYSVSEM)) |
| 177 | return -EINVAL; |
| 178 | |
| 179 | new_ns = create_new_namespaces(flags, tsk, user_ns, tsk->fs); |
| 180 | if (IS_ERR(new_ns)) |
| 181 | return PTR_ERR(new_ns); |
| 182 | |
| 183 | if ((flags & CLONE_VM) == 0) |
| 184 | timens_on_fork(new_ns, tsk); |
| 185 | |
| 186 | tsk->nsproxy = new_ns; |
| 187 | return 0; |
| 188 | } |
| 189 | |
| 190 | void free_nsproxy(struct nsproxy *ns) |
| 191 | { |
| 192 | if (ns->mnt_ns) |
| 193 | put_mnt_ns(ns->mnt_ns); |
| 194 | if (ns->uts_ns) |
| 195 | put_uts_ns(ns->uts_ns); |
| 196 | if (ns->ipc_ns) |
| 197 | put_ipc_ns(ns->ipc_ns); |
| 198 | if (ns->pid_ns_for_children) |
| 199 | put_pid_ns(ns->pid_ns_for_children); |
| 200 | if (ns->time_ns) |
| 201 | put_time_ns(ns->time_ns); |
| 202 | if (ns->time_ns_for_children) |
| 203 | put_time_ns(ns->time_ns_for_children); |
| 204 | put_cgroup_ns(ns->cgroup_ns); |
| 205 | put_net(ns->net_ns); |
| 206 | kmem_cache_free(nsproxy_cachep, ns); |
| 207 | } |
| 208 | |
| 209 | /* |
| 210 | * Called from unshare. Unshare all the namespaces part of nsproxy. |
| 211 | * On success, returns the new nsproxy. |
| 212 | */ |
| 213 | int unshare_nsproxy_namespaces(unsigned long unshare_flags, |
| 214 | struct nsproxy **new_nsp, struct cred *new_cred, struct fs_struct *new_fs) |
| 215 | { |
| 216 | struct user_namespace *user_ns; |
| 217 | int err = 0; |
| 218 | |
| 219 | if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | |
| 220 | CLONE_NEWNET | CLONE_NEWPID | CLONE_NEWCGROUP | |
| 221 | CLONE_NEWTIME))) |
| 222 | return 0; |
| 223 | |
| 224 | user_ns = new_cred ? new_cred->user_ns : current_user_ns(); |
| 225 | if (!ns_capable(user_ns, CAP_SYS_ADMIN)) |
| 226 | return -EPERM; |
| 227 | |
| 228 | *new_nsp = create_new_namespaces(unshare_flags, current, user_ns, |
| 229 | new_fs ? new_fs : current->fs); |
| 230 | if (IS_ERR(*new_nsp)) { |
| 231 | err = PTR_ERR(*new_nsp); |
| 232 | goto out; |
| 233 | } |
| 234 | |
| 235 | out: |
| 236 | return err; |
| 237 | } |
| 238 | |
| 239 | void switch_task_namespaces(struct task_struct *p, struct nsproxy *new) |
| 240 | { |
| 241 | struct nsproxy *ns; |
| 242 | |
| 243 | might_sleep(); |
| 244 | |
| 245 | task_lock(p); |
| 246 | ns = p->nsproxy; |
| 247 | p->nsproxy = new; |
| 248 | task_unlock(p); |
| 249 | |
| 250 | if (ns) |
| 251 | put_nsproxy(ns); |
| 252 | } |
| 253 | |
| 254 | void exit_task_namespaces(struct task_struct *p) |
| 255 | { |
| 256 | switch_task_namespaces(p, NULL); |
| 257 | } |
| 258 | |
| 259 | int exec_task_namespaces(void) |
| 260 | { |
| 261 | struct task_struct *tsk = current; |
| 262 | struct nsproxy *new; |
| 263 | |
| 264 | if (tsk->nsproxy->time_ns_for_children == tsk->nsproxy->time_ns) |
| 265 | return 0; |
| 266 | |
| 267 | new = create_new_namespaces(0, tsk, current_user_ns(), tsk->fs); |
| 268 | if (IS_ERR(new)) |
| 269 | return PTR_ERR(new); |
| 270 | |
| 271 | timens_on_fork(new, tsk); |
| 272 | switch_task_namespaces(tsk, new); |
| 273 | return 0; |
| 274 | } |
| 275 | |
| 276 | static int check_setns_flags(unsigned long flags) |
| 277 | { |
| 278 | if (!flags || (flags & ~(CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | |
| 279 | CLONE_NEWNET | CLONE_NEWTIME | CLONE_NEWUSER | |
| 280 | CLONE_NEWPID | CLONE_NEWCGROUP))) |
| 281 | return -EINVAL; |
| 282 | |
| 283 | #ifndef CONFIG_USER_NS |
| 284 | if (flags & CLONE_NEWUSER) |
| 285 | return -EINVAL; |
| 286 | #endif |
| 287 | #ifndef CONFIG_PID_NS |
| 288 | if (flags & CLONE_NEWPID) |
| 289 | return -EINVAL; |
| 290 | #endif |
| 291 | #ifndef CONFIG_UTS_NS |
| 292 | if (flags & CLONE_NEWUTS) |
| 293 | return -EINVAL; |
| 294 | #endif |
| 295 | #ifndef CONFIG_IPC_NS |
| 296 | if (flags & CLONE_NEWIPC) |
| 297 | return -EINVAL; |
| 298 | #endif |
| 299 | #ifndef CONFIG_CGROUPS |
| 300 | if (flags & CLONE_NEWCGROUP) |
| 301 | return -EINVAL; |
| 302 | #endif |
| 303 | #ifndef CONFIG_NET_NS |
| 304 | if (flags & CLONE_NEWNET) |
| 305 | return -EINVAL; |
| 306 | #endif |
| 307 | #ifndef CONFIG_TIME_NS |
| 308 | if (flags & CLONE_NEWTIME) |
| 309 | return -EINVAL; |
| 310 | #endif |
| 311 | |
| 312 | return 0; |
| 313 | } |
| 314 | |
| 315 | static void put_nsset(struct nsset *nsset) |
| 316 | { |
| 317 | unsigned flags = nsset->flags; |
| 318 | |
| 319 | if (flags & CLONE_NEWUSER) |
| 320 | put_cred(nsset_cred(nsset)); |
| 321 | /* |
| 322 | * We only created a temporary copy if we attached to more than just |
| 323 | * the mount namespace. |
| 324 | */ |
| 325 | if (nsset->fs && (flags & CLONE_NEWNS) && (flags & ~CLONE_NEWNS)) |
| 326 | free_fs_struct(nsset->fs); |
| 327 | if (nsset->nsproxy) |
| 328 | free_nsproxy(nsset->nsproxy); |
| 329 | } |
| 330 | |
| 331 | static int prepare_nsset(unsigned flags, struct nsset *nsset) |
| 332 | { |
| 333 | struct task_struct *me = current; |
| 334 | |
| 335 | nsset->nsproxy = create_new_namespaces(0, me, current_user_ns(), me->fs); |
| 336 | if (IS_ERR(nsset->nsproxy)) |
| 337 | return PTR_ERR(nsset->nsproxy); |
| 338 | |
| 339 | if (flags & CLONE_NEWUSER) |
| 340 | nsset->cred = prepare_creds(); |
| 341 | else |
| 342 | nsset->cred = current_cred(); |
| 343 | if (!nsset->cred) |
| 344 | goto out; |
| 345 | |
| 346 | /* Only create a temporary copy of fs_struct if we really need to. */ |
| 347 | if (flags == CLONE_NEWNS) { |
| 348 | nsset->fs = me->fs; |
| 349 | } else if (flags & CLONE_NEWNS) { |
| 350 | nsset->fs = copy_fs_struct(me->fs); |
| 351 | if (!nsset->fs) |
| 352 | goto out; |
| 353 | } |
| 354 | |
| 355 | nsset->flags = flags; |
| 356 | return 0; |
| 357 | |
| 358 | out: |
| 359 | put_nsset(nsset); |
| 360 | return -ENOMEM; |
| 361 | } |
| 362 | |
| 363 | static inline int validate_ns(struct nsset *nsset, struct ns_common *ns) |
| 364 | { |
| 365 | return ns->ops->install(nsset, ns); |
| 366 | } |
| 367 | |
| 368 | /* |
| 369 | * This is the inverse operation to unshare(). |
| 370 | * Ordering is equivalent to the standard ordering used everywhere else |
| 371 | * during unshare and process creation. The switch to the new set of |
| 372 | * namespaces occurs at the point of no return after installation of |
| 373 | * all requested namespaces was successful in commit_nsset(). |
| 374 | */ |
| 375 | static int validate_nsset(struct nsset *nsset, struct pid *pid) |
| 376 | { |
| 377 | int ret = 0; |
| 378 | unsigned flags = nsset->flags; |
| 379 | struct user_namespace *user_ns = NULL; |
| 380 | struct pid_namespace *pid_ns = NULL; |
| 381 | struct nsproxy *nsp; |
| 382 | struct task_struct *tsk; |
| 383 | |
| 384 | /* Take a "snapshot" of the target task's namespaces. */ |
| 385 | rcu_read_lock(); |
| 386 | tsk = pid_task(pid, PIDTYPE_PID); |
| 387 | if (!tsk) { |
| 388 | rcu_read_unlock(); |
| 389 | return -ESRCH; |
| 390 | } |
| 391 | |
| 392 | if (!ptrace_may_access(tsk, PTRACE_MODE_READ_REALCREDS)) { |
| 393 | rcu_read_unlock(); |
| 394 | return -EPERM; |
| 395 | } |
| 396 | |
| 397 | task_lock(tsk); |
| 398 | nsp = tsk->nsproxy; |
| 399 | if (nsp) |
| 400 | get_nsproxy(nsp); |
| 401 | task_unlock(tsk); |
| 402 | if (!nsp) { |
| 403 | rcu_read_unlock(); |
| 404 | return -ESRCH; |
| 405 | } |
| 406 | |
| 407 | #ifdef CONFIG_PID_NS |
| 408 | if (flags & CLONE_NEWPID) { |
| 409 | pid_ns = task_active_pid_ns(tsk); |
| 410 | if (unlikely(!pid_ns)) { |
| 411 | rcu_read_unlock(); |
| 412 | ret = -ESRCH; |
| 413 | goto out; |
| 414 | } |
| 415 | get_pid_ns(pid_ns); |
| 416 | } |
| 417 | #endif |
| 418 | |
| 419 | #ifdef CONFIG_USER_NS |
| 420 | if (flags & CLONE_NEWUSER) |
| 421 | user_ns = get_user_ns(__task_cred(tsk)->user_ns); |
| 422 | #endif |
| 423 | rcu_read_unlock(); |
| 424 | |
| 425 | /* |
| 426 | * Install requested namespaces. The caller will have |
| 427 | * verified earlier that the requested namespaces are |
| 428 | * supported on this kernel. We don't report errors here |
| 429 | * if a namespace is requested that isn't supported. |
| 430 | */ |
| 431 | #ifdef CONFIG_USER_NS |
| 432 | if (flags & CLONE_NEWUSER) { |
| 433 | ret = validate_ns(nsset, &user_ns->ns); |
| 434 | if (ret) |
| 435 | goto out; |
| 436 | } |
| 437 | #endif |
| 438 | |
| 439 | if (flags & CLONE_NEWNS) { |
| 440 | ret = validate_ns(nsset, from_mnt_ns(nsp->mnt_ns)); |
| 441 | if (ret) |
| 442 | goto out; |
| 443 | } |
| 444 | |
| 445 | #ifdef CONFIG_UTS_NS |
| 446 | if (flags & CLONE_NEWUTS) { |
| 447 | ret = validate_ns(nsset, &nsp->uts_ns->ns); |
| 448 | if (ret) |
| 449 | goto out; |
| 450 | } |
| 451 | #endif |
| 452 | |
| 453 | #ifdef CONFIG_IPC_NS |
| 454 | if (flags & CLONE_NEWIPC) { |
| 455 | ret = validate_ns(nsset, &nsp->ipc_ns->ns); |
| 456 | if (ret) |
| 457 | goto out; |
| 458 | } |
| 459 | #endif |
| 460 | |
| 461 | #ifdef CONFIG_PID_NS |
| 462 | if (flags & CLONE_NEWPID) { |
| 463 | ret = validate_ns(nsset, &pid_ns->ns); |
| 464 | if (ret) |
| 465 | goto out; |
| 466 | } |
| 467 | #endif |
| 468 | |
| 469 | #ifdef CONFIG_CGROUPS |
| 470 | if (flags & CLONE_NEWCGROUP) { |
| 471 | ret = validate_ns(nsset, &nsp->cgroup_ns->ns); |
| 472 | if (ret) |
| 473 | goto out; |
| 474 | } |
| 475 | #endif |
| 476 | |
| 477 | #ifdef CONFIG_NET_NS |
| 478 | if (flags & CLONE_NEWNET) { |
| 479 | ret = validate_ns(nsset, &nsp->net_ns->ns); |
| 480 | if (ret) |
| 481 | goto out; |
| 482 | } |
| 483 | #endif |
| 484 | |
| 485 | #ifdef CONFIG_TIME_NS |
| 486 | if (flags & CLONE_NEWTIME) { |
| 487 | ret = validate_ns(nsset, &nsp->time_ns->ns); |
| 488 | if (ret) |
| 489 | goto out; |
| 490 | } |
| 491 | #endif |
| 492 | |
| 493 | out: |
| 494 | if (pid_ns) |
| 495 | put_pid_ns(pid_ns); |
| 496 | if (nsp) |
| 497 | put_nsproxy(nsp); |
| 498 | put_user_ns(user_ns); |
| 499 | |
| 500 | return ret; |
| 501 | } |
| 502 | |
| 503 | /* |
| 504 | * This is the point of no return. There are just a few namespaces |
| 505 | * that do some actual work here and it's sufficiently minimal that |
| 506 | * a separate ns_common operation seems unnecessary for now. |
| 507 | * Unshare is doing the same thing. If we'll end up needing to do |
| 508 | * more in a given namespace or a helper here is ultimately not |
| 509 | * exported anymore a simple commit handler for each namespace |
| 510 | * should be added to ns_common. |
| 511 | */ |
| 512 | static void commit_nsset(struct nsset *nsset) |
| 513 | { |
| 514 | unsigned flags = nsset->flags; |
| 515 | struct task_struct *me = current; |
| 516 | |
| 517 | #ifdef CONFIG_USER_NS |
| 518 | if (flags & CLONE_NEWUSER) { |
| 519 | /* transfer ownership */ |
| 520 | commit_creds(nsset_cred(nsset)); |
| 521 | nsset->cred = NULL; |
| 522 | } |
| 523 | #endif |
| 524 | |
| 525 | /* We only need to commit if we have used a temporary fs_struct. */ |
| 526 | if ((flags & CLONE_NEWNS) && (flags & ~CLONE_NEWNS)) { |
| 527 | set_fs_root(me->fs, &nsset->fs->root); |
| 528 | set_fs_pwd(me->fs, &nsset->fs->pwd); |
| 529 | } |
| 530 | |
| 531 | #ifdef CONFIG_IPC_NS |
| 532 | if (flags & CLONE_NEWIPC) |
| 533 | exit_sem(me); |
| 534 | #endif |
| 535 | |
| 536 | #ifdef CONFIG_TIME_NS |
| 537 | if (flags & CLONE_NEWTIME) |
| 538 | timens_commit(me, nsset->nsproxy->time_ns); |
| 539 | #endif |
| 540 | |
| 541 | /* transfer ownership */ |
| 542 | switch_task_namespaces(me, nsset->nsproxy); |
| 543 | nsset->nsproxy = NULL; |
| 544 | } |
| 545 | |
| 546 | SYSCALL_DEFINE2(setns, int, fd, int, flags) |
| 547 | { |
| 548 | struct fd f = fdget(fd); |
| 549 | struct ns_common *ns = NULL; |
| 550 | struct nsset nsset = {}; |
| 551 | int err = 0; |
| 552 | |
| 553 | if (!f.file) |
| 554 | return -EBADF; |
| 555 | |
| 556 | if (proc_ns_file(f.file)) { |
| 557 | ns = get_proc_ns(file_inode(f.file)); |
| 558 | if (flags && (ns->ops->type != flags)) |
| 559 | err = -EINVAL; |
| 560 | flags = ns->ops->type; |
| 561 | } else if (!IS_ERR(pidfd_pid(f.file))) { |
| 562 | err = check_setns_flags(flags); |
| 563 | } else { |
| 564 | err = -EINVAL; |
| 565 | } |
| 566 | if (err) |
| 567 | goto out; |
| 568 | |
| 569 | err = prepare_nsset(flags, &nsset); |
| 570 | if (err) |
| 571 | goto out; |
| 572 | |
| 573 | if (proc_ns_file(f.file)) |
| 574 | err = validate_ns(&nsset, ns); |
| 575 | else |
| 576 | err = validate_nsset(&nsset, f.file->private_data); |
| 577 | if (!err) { |
| 578 | commit_nsset(&nsset); |
| 579 | perf_event_namespaces(current); |
| 580 | } |
| 581 | put_nsset(&nsset); |
| 582 | out: |
| 583 | fdput(f); |
| 584 | return err; |
| 585 | } |
| 586 | |
| 587 | int __init nsproxy_cache_init(void) |
| 588 | { |
| 589 | nsproxy_cachep = KMEM_CACHE(nsproxy, SLAB_PANIC|SLAB_ACCOUNT); |
| 590 | return 0; |
| 591 | } |