linux/kernel/seccomp.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * linux/kernel/seccomp.c
   4 *
   5 * Copyright 2004-2005  Andrea Arcangeli <andrea@cpushare.com>
   6 *
   7 * Copyright (C) 2012 Google, Inc.
   8 * Will Drewry <wad@chromium.org>
   9 *
  10 * This defines a simple but solid secure-computing facility.
  11 *
  12 * Mode 1 uses a fixed list of allowed system calls.
  13 * Mode 2 allows user-defined system call filters in the form
  14 *        of Berkeley Packet Filters/Linux Socket Filters.
  15 */
  16
  17#include <linux/refcount.h>
  18#include <linux/audit.h>
  19#include <linux/compat.h>
  20#include <linux/coredump.h>
  21#include <linux/kmemleak.h>
  22#include <linux/nospec.h>
  23#include <linux/prctl.h>
  24#include <linux/sched.h>
  25#include <linux/sched/task_stack.h>
  26#include <linux/seccomp.h>
  27#include <linux/slab.h>
  28#include <linux/syscalls.h>
  29#include <linux/sysctl.h>
  30
  31#ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER
  32#include <asm/syscall.h>
  33#endif
  34
  35#ifdef CONFIG_SECCOMP_FILTER
  36#include <linux/filter.h>
  37#include <linux/pid.h>
  38#include <linux/ptrace.h>
  39#include <linux/security.h>
  40#include <linux/tracehook.h>
  41#include <linux/uaccess.h>
  42
  43/**
  44 * struct seccomp_filter - container for seccomp BPF programs
  45 *
  46 * @usage: reference count to manage the object lifetime.
  47 *         get/put helpers should be used when accessing an instance
  48 *         outside of a lifetime-guarded section.  In general, this
  49 *         is only needed for handling filters shared across tasks.
  50 * @log: true if all actions except for SECCOMP_RET_ALLOW should be logged
  51 * @prev: points to a previously installed, or inherited, filter
  52 * @prog: the BPF program to evaluate
  53 *
  54 * seccomp_filter objects are organized in a tree linked via the @prev
  55 * pointer.  For any task, it appears to be a singly-linked list starting
  56 * with current->seccomp.filter, the most recently attached or inherited filter.
  57 * However, multiple filters may share a @prev node, by way of fork(), which
  58 * results in a unidirectional tree existing in memory.  This is similar to
  59 * how namespaces work.
  60 *
  61 * seccomp_filter objects should never be modified after being attached
  62 * to a task_struct (other than @usage).
  63 */
  64struct seccomp_filter {
  65        refcount_t usage;
  66        bool log;
  67        struct seccomp_filter *prev;
  68        struct bpf_prog *prog;
  69};
  70
  71/* Limit any path through the tree to 256KB worth of instructions. */
  72#define MAX_INSNS_PER_PATH ((1 << 18) / sizeof(struct sock_filter))
  73
  74/*
  75 * Endianness is explicitly ignored and left for BPF program authors to manage
  76 * as per the specific architecture.
  77 */
  78static void populate_seccomp_data(struct seccomp_data *sd)
  79{
  80        struct task_struct *task = current;
  81        struct pt_regs *regs = task_pt_regs(task);
  82        unsigned long args[6];
  83
  84        sd->nr = syscall_get_nr(task, regs);
  85        sd->arch = syscall_get_arch(task);
  86        syscall_get_arguments(task, regs, 0, 6, args);
  87        sd->args[0] = args[0];
  88        sd->args[1] = args[1];
  89        sd->args[2] = args[2];
  90        sd->args[3] = args[3];
  91        sd->args[4] = args[4];
  92        sd->args[5] = args[5];
  93        sd->instruction_pointer = KSTK_EIP(task);
  94}
  95
  96/**
  97 *      seccomp_check_filter - verify seccomp filter code
  98 *      @filter: filter to verify
  99 *      @flen: length of filter
 100 *
 101 * Takes a previously checked filter (by bpf_check_classic) and
 102 * redirects all filter code that loads struct sk_buff data
 103 * and related data through seccomp_bpf_load.  It also
 104 * enforces length and alignment checking of those loads.
 105 *
 106 * Returns 0 if the rule set is legal or -EINVAL if not.
 107 */
 108static int seccomp_check_filter(struct sock_filter *filter, unsigned int flen)
 109{
 110        int pc;
 111        for (pc = 0; pc < flen; pc++) {
 112                struct sock_filter *ftest = &filter[pc];
 113                u16 code = ftest->code;
 114                u32 k = ftest->k;
 115
 116                switch (code) {
 117                case BPF_LD | BPF_W | BPF_ABS:
 118                        ftest->code = BPF_LDX | BPF_W | BPF_ABS;
 119                        /* 32-bit aligned and not out of bounds. */
 120                        if (k >= sizeof(struct seccomp_data) || k & 3)
 121                                return -EINVAL;
 122                        continue;
 123                case BPF_LD | BPF_W | BPF_LEN:
 124                        ftest->code = BPF_LD | BPF_IMM;
 125                        ftest->k = sizeof(struct seccomp_data);
 126                        continue;
 127                case BPF_LDX | BPF_W | BPF_LEN:
 128                        ftest->code = BPF_LDX | BPF_IMM;
 129                        ftest->k = sizeof(struct seccomp_data);
 130                        continue;
 131                /* Explicitly include allowed calls. */
 132                case BPF_RET | BPF_K:
 133                case BPF_RET | BPF_A:
 134                case BPF_ALU | BPF_ADD | BPF_K:
 135                case BPF_ALU | BPF_ADD | BPF_X:
 136                case BPF_ALU | BPF_SUB | BPF_K:
 137                case BPF_ALU | BPF_SUB | BPF_X:
 138                case BPF_ALU | BPF_MUL | BPF_K:
 139                case BPF_ALU | BPF_MUL | BPF_X:
 140                case BPF_ALU | BPF_DIV | BPF_K:
 141                case BPF_ALU | BPF_DIV | BPF_X:
 142                case BPF_ALU | BPF_AND | BPF_K:
 143                case BPF_ALU | BPF_AND | BPF_X:
 144                case BPF_ALU | BPF_OR | BPF_K:
 145                case BPF_ALU | BPF_OR | BPF_X:
 146                case BPF_ALU | BPF_XOR | BPF_K:
 147                case BPF_ALU | BPF_XOR | BPF_X:
 148                case BPF_ALU | BPF_LSH | BPF_K:
 149                case BPF_ALU | BPF_LSH | BPF_X:
 150                case BPF_ALU | BPF_RSH | BPF_K:
 151                case BPF_ALU | BPF_RSH | BPF_X:
 152                case BPF_ALU | BPF_NEG:
 153                case BPF_LD | BPF_IMM:
 154                case BPF_LDX | BPF_IMM:
 155                case BPF_MISC | BPF_TAX:
 156                case BPF_MISC | BPF_TXA:
 157                case BPF_LD | BPF_MEM:
 158                case BPF_LDX | BPF_MEM:
 159                case BPF_ST:
 160                case BPF_STX:
 161                case BPF_JMP | BPF_JA:
 162                case BPF_JMP | BPF_JEQ | BPF_K:
 163                case BPF_JMP | BPF_JEQ | BPF_X:
 164                case BPF_JMP | BPF_JGE | BPF_K:
 165                case BPF_JMP | BPF_JGE | BPF_X:
 166                case BPF_JMP | BPF_JGT | BPF_K:
 167                case BPF_JMP | BPF_JGT | BPF_X:
 168                case BPF_JMP | BPF_JSET | BPF_K:
 169                case BPF_JMP | BPF_JSET | BPF_X:
 170                        continue;
 171                default:
 172                        return -EINVAL;
 173                }
 174        }
 175        return 0;
 176}
 177
 178/**
 179 * seccomp_run_filters - evaluates all seccomp filters against @sd
 180 * @sd: optional seccomp data to be passed to filters
 181 * @match: stores struct seccomp_filter that resulted in the return value,
 182 *         unless filter returned SECCOMP_RET_ALLOW, in which case it will
 183 *         be unchanged.
 184 *
 185 * Returns valid seccomp BPF response codes.
 186 */
 187#define ACTION_ONLY(ret) ((s32)((ret) & (SECCOMP_RET_ACTION_FULL)))
 188static u32 seccomp_run_filters(const struct seccomp_data *sd,
 189                               struct seccomp_filter **match)
 190{
 191        struct seccomp_data sd_local;
 192        u32 ret = SECCOMP_RET_ALLOW;
 193        /* Make sure cross-thread synced filter points somewhere sane. */
 194        struct seccomp_filter *f =
 195                        READ_ONCE(current->seccomp.filter);
 196
 197        /* Ensure unexpected behavior doesn't result in failing open. */
 198        if (unlikely(WARN_ON(f == NULL)))
 199                return SECCOMP_RET_KILL_PROCESS;
 200
 201        if (!sd) {
 202                populate_seccomp_data(&sd_local);
 203                sd = &sd_local;
 204        }
 205
 206        /*
 207         * All filters in the list are evaluated and the lowest BPF return
 208         * value always takes priority (ignoring the DATA).
 209         */
 210        for (; f; f = f->prev) {
 211                u32 cur_ret = bpf_prog_run_pin_on_cpu(f->prog, sd);
 212
 213                if (ACTION_ONLY(cur_ret) < ACTION_ONLY(ret)) {
 214                        ret = cur_ret;
 215                        *match = f;
 216                }
 217        }
 218        return ret;
 219}
 220#endif /* CONFIG_SECCOMP_FILTER */
 221
 222static inline bool seccomp_may_assign_mode(unsigned long seccomp_mode)
 223{
 224        assert_spin_locked(&current->sighand->siglock);
 225
 226        if (current->seccomp.mode && current->seccomp.mode != seccomp_mode)
 227                return false;
 228
 229        return true;
 230}
 231
 232void __weak arch_seccomp_spec_mitigate(struct task_struct *task) { }
 233
 234static inline void seccomp_assign_mode(struct task_struct *task,
 235                                       unsigned long seccomp_mode,
 236                                       unsigned long flags)
 237{
 238        assert_spin_locked(&task->sighand->siglock);
 239
 240        task->seccomp.mode = seccomp_mode;
 241        /*
 242         * Make sure TIF_SECCOMP cannot be set before the mode (and
 243         * filter) is set.
 244         */
 245        smp_mb__before_atomic();
 246        /* Assume default seccomp processes want spec flaw mitigation. */
 247        if ((flags & SECCOMP_FILTER_FLAG_SPEC_ALLOW) == 0)
 248                arch_seccomp_spec_mitigate(task);
 249        set_tsk_thread_flag(task, TIF_SECCOMP);
 250}
 251
 252#ifdef CONFIG_SECCOMP_FILTER
 253/* Returns 1 if the parent is an ancestor of the child. */
 254static int is_ancestor(struct seccomp_filter *parent,
 255                       struct seccomp_filter *child)
 256{
 257        /* NULL is the root ancestor. */
 258        if (parent == NULL)
 259                return 1;
 260        for (; child; child = child->prev)
 261                if (child == parent)
 262                        return 1;
 263        return 0;
 264}
 265
 266/**
 267 * seccomp_can_sync_threads: checks if all threads can be synchronized
 268 *
 269 * Expects sighand and cred_guard_mutex locks to be held.
 270 *
 271 * Returns 0 on success, -ve on error, or the pid of a thread which was
 272 * either not in the correct seccomp mode or it did not have an ancestral
 273 * seccomp filter.
 274 */
 275static inline pid_t seccomp_can_sync_threads(void)
 276{
 277        struct task_struct *thread, *caller;
 278
 279        BUG_ON(!mutex_is_locked(&current->signal->cred_guard_mutex));
 280        assert_spin_locked(&current->sighand->siglock);
 281
 282        /* Validate all threads being eligible for synchronization. */
 283        caller = current;
 284        for_each_thread(caller, thread) {
 285                pid_t failed;
 286
 287                /* Skip current, since it is initiating the sync. */
 288                if (thread == caller)
 289                        continue;
 290
 291                if (thread->seccomp.mode == SECCOMP_MODE_DISABLED ||
 292                    (thread->seccomp.mode == SECCOMP_MODE_FILTER &&
 293                     is_ancestor(thread->seccomp.filter,
 294                                 caller->seccomp.filter)))
 295                        continue;
 296
 297                /* Return the first thread that cannot be synchronized. */
 298                failed = task_pid_vnr(thread);
 299                /* If the pid cannot be resolved, then return -ESRCH */
 300                if (unlikely(WARN_ON(failed == 0)))
 301                        failed = -ESRCH;
 302                return failed;
 303        }
 304
 305        return 0;
 306}
 307
 308/**
 309 * seccomp_sync_threads: sets all threads to use current's filter
 310 *
 311 * Expects sighand and cred_guard_mutex locks to be held, and for
 312 * seccomp_can_sync_threads() to have returned success already
 313 * without dropping the locks.
 314 *
 315 */
 316static inline void seccomp_sync_threads(unsigned long flags)
 317{
 318        struct task_struct *thread, *caller;
 319
 320        BUG_ON(!mutex_is_locked(&current->signal->cred_guard_mutex));
 321        assert_spin_locked(&current->sighand->siglock);
 322
 323        /* Synchronize all threads. */
 324        caller = current;
 325        for_each_thread(caller, thread) {
 326                /* Skip current, since it needs no changes. */
 327                if (thread == caller)
 328                        continue;
 329
 330                /* Get a task reference for the new leaf node. */
 331                get_seccomp_filter(caller);
 332                /*
 333                 * Drop the task reference to the shared ancestor since
 334                 * current's path will hold a reference.  (This also
 335                 * allows a put before the assignment.)
 336                 */
 337                put_seccomp_filter(thread);
 338                smp_store_release(&thread->seccomp.filter,
 339                                  caller->seccomp.filter);
 340
 341                /*
 342                 * Don't let an unprivileged task work around
 343                 * the no_new_privs restriction by creating
 344                 * a thread that sets it up, enters seccomp,
 345                 * then dies.
 346                 */
 347                if (task_no_new_privs(caller))
 348                        task_set_no_new_privs(thread);
 349
 350                /*
 351                 * Opt the other thread into seccomp if needed.
 352                 * As threads are considered to be trust-realm
 353                 * equivalent (see ptrace_may_access), it is safe to
 354                 * allow one thread to transition the other.
 355                 */
 356                if (thread->seccomp.mode == SECCOMP_MODE_DISABLED)
 357                        seccomp_assign_mode(thread, SECCOMP_MODE_FILTER,
 358                                            flags);
 359        }
 360}
 361
 362/**
 363 * seccomp_prepare_filter: Prepares a seccomp filter for use.
 364 * @fprog: BPF program to install
 365 *
 366 * Returns filter on success or an ERR_PTR on failure.
 367 */
 368static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog)
 369{
 370        struct seccomp_filter *sfilter;
 371        int ret;
 372        const bool save_orig = IS_ENABLED(CONFIG_CHECKPOINT_RESTORE);
 373
 374        if (fprog->len == 0 || fprog->len > BPF_MAXINSNS)
 375                return ERR_PTR(-EINVAL);
 376
 377        BUG_ON(INT_MAX / fprog->len < sizeof(struct sock_filter));
 378
 379        /*
 380         * Installing a seccomp filter requires that the task has
 381         * CAP_SYS_ADMIN in its namespace or be running with no_new_privs.
 382         * This avoids scenarios where unprivileged tasks can affect the
 383         * behavior of privileged children.
 384         */
 385        if (!task_no_new_privs(current) &&
 386            security_capable(current_cred(), current_user_ns(),
 387                                     CAP_SYS_ADMIN, CAP_OPT_NOAUDIT) != 0)
 388                return ERR_PTR(-EACCES);
 389
 390        /* Allocate a new seccomp_filter */
 391        sfilter = kzalloc(sizeof(*sfilter), GFP_KERNEL | __GFP_NOWARN);
 392        if (!sfilter)
 393                return ERR_PTR(-ENOMEM);
 394
 395        ret = bpf_prog_create_from_user(&sfilter->prog, fprog,
 396                                        seccomp_check_filter, save_orig);
 397        if (ret < 0) {
 398                kfree(sfilter);
 399                return ERR_PTR(ret);
 400        }
 401
 402        refcount_set(&sfilter->usage, 1);
 403
 404        return sfilter;
 405}
 406
 407/**
 408 * seccomp_prepare_user_filter - prepares a user-supplied sock_fprog
 409 * @user_filter: pointer to the user data containing a sock_fprog.
 410 *
 411 * Returns 0 on success and non-zero otherwise.
 412 */
 413static struct seccomp_filter *
 414seccomp_prepare_user_filter(const char __user *user_filter)
 415{
 416        struct sock_fprog fprog;
 417        struct seccomp_filter *filter = ERR_PTR(-EFAULT);
 418
 419#ifdef CONFIG_COMPAT
 420        if (in_compat_syscall()) {
 421                struct compat_sock_fprog fprog32;
 422                if (copy_from_user(&fprog32, user_filter, sizeof(fprog32)))
 423                        goto out;
 424                fprog.len = fprog32.len;
 425                fprog.filter = compat_ptr(fprog32.filter);
 426        } else /* falls through to the if below. */
 427#endif
 428        if (copy_from_user(&fprog, user_filter, sizeof(fprog)))
 429                goto out;
 430        filter = seccomp_prepare_filter(&fprog);
 431out:
 432        return filter;
 433}
 434
 435/**
 436 * seccomp_attach_filter: validate and attach filter
 437 * @flags:  flags to change filter behavior
 438 * @filter: seccomp filter to add to the current process
 439 *
 440 * Caller must be holding current->sighand->siglock lock.
 441 *
 442 * Returns 0 on success, -ve on error.
 443 */
 444static long seccomp_attach_filter(unsigned int flags,
 445                                  struct seccomp_filter *filter)
 446{
 447        unsigned long total_insns;
 448        struct seccomp_filter *walker;
 449
 450        assert_spin_locked(&current->sighand->siglock);
 451
 452        /* Validate resulting filter length. */
 453        total_insns = filter->prog->len;
 454        for (walker = current->seccomp.filter; walker; walker = walker->prev)
 455                total_insns += walker->prog->len + 4;  /* 4 instr penalty */
 456        if (total_insns > MAX_INSNS_PER_PATH)
 457                return -ENOMEM;
 458
 459        /* If thread sync has been requested, check that it is possible. */
 460        if (flags & SECCOMP_FILTER_FLAG_TSYNC) {
 461                int ret;
 462
 463                ret = seccomp_can_sync_threads();
 464                if (ret)
 465                        return ret;
 466        }
 467
 468        /* Set log flag, if present. */
 469        if (flags & SECCOMP_FILTER_FLAG_LOG)
 470                filter->log = true;
 471
 472        /*
 473         * If there is an existing filter, make it the prev and don't drop its
 474         * task reference.
 475         */
 476        filter->prev = current->seccomp.filter;
 477        current->seccomp.filter = filter;
 478
 479        /* Now that the new filter is in place, synchronize to all threads. */
 480        if (flags & SECCOMP_FILTER_FLAG_TSYNC)
 481                seccomp_sync_threads(flags);
 482
 483        return 0;
 484}
 485
 486static void __get_seccomp_filter(struct seccomp_filter *filter)
 487{
 488        /* Reference count is bounded by the number of total processes. */
 489        refcount_inc(&filter->usage);
 490}
 491
 492/* get_seccomp_filter - increments the reference count of the filter on @tsk */
 493void get_seccomp_filter(struct task_struct *tsk)
 494{
 495        struct seccomp_filter *orig = tsk->seccomp.filter;
 496        if (!orig)
 497                return;
 498        __get_seccomp_filter(orig);
 499}
 500
 501static inline void seccomp_filter_free(struct seccomp_filter *filter)
 502{
 503        if (filter) {
 504                bpf_prog_destroy(filter->prog);
 505                kfree(filter);
 506        }
 507}
 508
 509static void __put_seccomp_filter(struct seccomp_filter *orig)
 510{
 511        /* Clean up single-reference branches iteratively. */
 512        while (orig && refcount_dec_and_test(&orig->usage)) {
 513                struct seccomp_filter *freeme = orig;
 514                orig = orig->prev;
 515                seccomp_filter_free(freeme);
 516        }
 517}
 518
 519/* put_seccomp_filter - decrements the ref count of tsk->seccomp.filter */
 520void put_seccomp_filter(struct task_struct *tsk)
 521{
 522        __put_seccomp_filter(tsk->seccomp.filter);
 523}
 524
 525static void seccomp_init_siginfo(kernel_siginfo_t *info, int syscall, int reason)
 526{
 527        clear_siginfo(info);
 528        info->si_signo = SIGSYS;
 529        info->si_code = SYS_SECCOMP;
 530        info->si_call_addr = (void __user *)KSTK_EIP(current);
 531        info->si_errno = reason;
 532        info->si_arch = syscall_get_arch(current);
 533        info->si_syscall = syscall;
 534}
 535
 536/**
 537 * seccomp_send_sigsys - signals the task to allow in-process syscall emulation
 538 * @syscall: syscall number to send to userland
 539 * @reason: filter-supplied reason code to send to userland (via si_errno)
 540 *
 541 * Forces a SIGSYS with a code of SYS_SECCOMP and related sigsys info.
 542 */
 543static void seccomp_send_sigsys(int syscall, int reason)
 544{
 545        struct kernel_siginfo info;
 546        seccomp_init_siginfo(&info, syscall, reason);
 547        force_sig_info(SIGSYS, &info, current);
 548}
 549#endif  /* CONFIG_SECCOMP_FILTER */
 550
 551/* For use with seccomp_actions_logged */
 552#define SECCOMP_LOG_KILL_PROCESS        (1 << 0)
 553#define SECCOMP_LOG_KILL_THREAD         (1 << 1)
 554#define SECCOMP_LOG_TRAP                (1 << 2)
 555#define SECCOMP_LOG_ERRNO               (1 << 3)
 556#define SECCOMP_LOG_TRACE               (1 << 4)
 557#define SECCOMP_LOG_LOG                 (1 << 5)
 558#define SECCOMP_LOG_ALLOW               (1 << 6)
 559
 560static u32 seccomp_actions_logged = SECCOMP_LOG_KILL_PROCESS |
 561                                    SECCOMP_LOG_KILL_THREAD  |
 562                                    SECCOMP_LOG_TRAP  |
 563                                    SECCOMP_LOG_ERRNO |
 564                                    SECCOMP_LOG_TRACE |
 565                                    SECCOMP_LOG_LOG;
 566
 567static inline void seccomp_log(unsigned long syscall, long signr, u32 action,
 568                               bool requested)
 569{
 570        bool log = false;
 571
 572        switch (action) {
 573        case SECCOMP_RET_ALLOW:
 574                break;
 575        case SECCOMP_RET_TRAP:
 576                log = requested && seccomp_actions_logged & SECCOMP_LOG_TRAP;
 577                break;
 578        case SECCOMP_RET_ERRNO:
 579                log = requested && seccomp_actions_logged & SECCOMP_LOG_ERRNO;
 580                break;
 581        case SECCOMP_RET_TRACE:
 582                log = requested && seccomp_actions_logged & SECCOMP_LOG_TRACE;
 583                break;
 584        case SECCOMP_RET_LOG:
 585                log = seccomp_actions_logged & SECCOMP_LOG_LOG;
 586                break;
 587        case SECCOMP_RET_KILL_THREAD:
 588                log = seccomp_actions_logged & SECCOMP_LOG_KILL_THREAD;
 589                break;
 590        case SECCOMP_RET_KILL_PROCESS:
 591        default:
 592                log = seccomp_actions_logged & SECCOMP_LOG_KILL_PROCESS;
 593        }
 594
 595        /*
 596         * Emit an audit message when the action is RET_KILL_*, RET_LOG, or the
 597         * FILTER_FLAG_LOG bit was set. The admin has the ability to silence
 598         * any action from being logged by removing the action name from the
 599         * seccomp_actions_logged sysctl.
 600         */
 601        if (!log)
 602                return;
 603
 604        audit_seccomp(syscall, signr, action);
 605}
 606
 607/*
 608 * Secure computing mode 1 allows only read/write/exit/sigreturn.
 609 * To be fully secure this must be combined with rlimit
 610 * to limit the stack allocations too.
 611 */
 612static const int mode1_syscalls[] = {
 613        __NR_seccomp_read, __NR_seccomp_write, __NR_seccomp_exit, __NR_seccomp_sigreturn,
 614        0, /* null terminated */
 615};
 616
 617static void __secure_computing_strict(int this_syscall)
 618{
 619        const int *syscall_whitelist = mode1_syscalls;
 620#ifdef CONFIG_COMPAT
 621        if (in_compat_syscall())
 622                syscall_whitelist = get_compat_mode1_syscalls();
 623#endif
 624        do {
 625                if (*syscall_whitelist == this_syscall)
 626                        return;
 627        } while (*++syscall_whitelist);
 628
 629#ifdef SECCOMP_DEBUG
 630        dump_stack();
 631#endif
 632        seccomp_log(this_syscall, SIGKILL, SECCOMP_RET_KILL_THREAD, true);
 633        do_exit(SIGKILL);
 634}
 635
 636#ifndef CONFIG_HAVE_ARCH_SECCOMP_FILTER
 637void secure_computing_strict(int this_syscall)
 638{
 639        int mode = current->seccomp.mode;
 640
 641        if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) &&
 642            unlikely(current->ptrace & PT_SUSPEND_SECCOMP))
 643                return;
 644
 645        if (mode == SECCOMP_MODE_DISABLED)
 646                return;
 647        else if (mode == SECCOMP_MODE_STRICT)
 648                __secure_computing_strict(this_syscall);
 649        else
 650                BUG();
 651}
 652#else
 653
 654#ifdef CONFIG_SECCOMP_FILTER
 655static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd,
 656                            const bool recheck_after_trace)
 657{
 658        u32 filter_ret, action;
 659        struct seccomp_filter *match = NULL;
 660        int data;
 661
 662        /*
 663         * Make sure that any changes to mode from another thread have
 664         * been seen after TIF_SECCOMP was seen.
 665         */
 666        rmb();
 667
 668        filter_ret = seccomp_run_filters(sd, &match);
 669        data = filter_ret & SECCOMP_RET_DATA;
 670        action = filter_ret & SECCOMP_RET_ACTION_FULL;
 671
 672        switch (action) {
 673        case SECCOMP_RET_ERRNO:
 674                /* Set low-order bits as an errno, capped at MAX_ERRNO. */
 675                if (data > MAX_ERRNO)
 676                        data = MAX_ERRNO;
 677                syscall_set_return_value(current, task_pt_regs(current),
 678                                         -data, 0);
 679                goto skip;
 680
 681        case SECCOMP_RET_TRAP:
 682                /* Show the handler the original registers. */
 683                syscall_rollback(current, task_pt_regs(current));
 684                /* Let the filter pass back 16 bits of data. */
 685                seccomp_send_sigsys(this_syscall, data);
 686                goto skip;
 687
 688        case SECCOMP_RET_TRACE:
 689                /* We've been put in this state by the ptracer already. */
 690                if (recheck_after_trace)
 691                        return 0;
 692
 693                /* ENOSYS these calls if there is no tracer attached. */
 694                if (!ptrace_event_enabled(current, PTRACE_EVENT_SECCOMP)) {
 695                        syscall_set_return_value(current,
 696                                                 task_pt_regs(current),
 697                                                 -ENOSYS, 0);
 698                        goto skip;
 699                }
 700
 701                /* Allow the BPF to provide the event message */
 702                ptrace_event(PTRACE_EVENT_SECCOMP, data);
 703                /*
 704                 * The delivery of a fatal signal during event
 705                 * notification may silently skip tracer notification,
 706                 * which could leave us with a potentially unmodified
 707                 * syscall that the tracer would have liked to have
 708                 * changed. Since the process is about to die, we just
 709                 * force the syscall to be skipped and let the signal
 710                 * kill the process and correctly handle any tracer exit
 711                 * notifications.
 712                 */
 713                if (fatal_signal_pending(current))
 714                        goto skip;
 715                /* Check if the tracer forced the syscall to be skipped. */
 716                this_syscall = syscall_get_nr(current, task_pt_regs(current));
 717                if (this_syscall < 0)
 718                        goto skip;
 719
 720                /*
 721                 * Recheck the syscall, since it may have changed. This
 722                 * intentionally uses a NULL struct seccomp_data to force
 723                 * a reload of all registers. This does not goto skip since
 724                 * a skip would have already been reported.
 725                 */
 726                if (__seccomp_filter(this_syscall, NULL, true))
 727                        return -1;
 728
 729                return 0;
 730
 731        case SECCOMP_RET_LOG:
 732                seccomp_log(this_syscall, 0, action, true);
 733                return 0;
 734
 735        case SECCOMP_RET_ALLOW:
 736                /*
 737                 * Note that the "match" filter will always be NULL for
 738                 * this action since SECCOMP_RET_ALLOW is the starting
 739                 * state in seccomp_run_filters().
 740                 */
 741                return 0;
 742
 743        case SECCOMP_RET_KILL_THREAD:
 744        case SECCOMP_RET_KILL_PROCESS:
 745        default:
 746                seccomp_log(this_syscall, SIGSYS, action, true);
 747                /* Dump core only if this is the last remaining thread. */
 748                if (action == SECCOMP_RET_KILL_PROCESS ||
 749                    get_nr_threads(current) == 1) {
 750                        kernel_siginfo_t info;
 751
 752                        /* Show the original registers in the dump. */
 753                        syscall_rollback(current, task_pt_regs(current));
 754                        /* Trigger a manual coredump since do_exit skips it. */
 755                        seccomp_init_siginfo(&info, this_syscall, data);
 756                        do_coredump(&info);
 757                }
 758                if (action == SECCOMP_RET_KILL_PROCESS)
 759                        do_group_exit(SIGSYS);
 760                else
 761                        do_exit(SIGSYS);
 762        }
 763
 764        unreachable();
 765
 766skip:
 767        seccomp_log(this_syscall, 0, action, match ? match->log : false);
 768        return -1;
 769}
 770#else
 771static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd,
 772                            const bool recheck_after_trace)
 773{
 774        BUG();
 775}
 776#endif
 777
 778int __secure_computing(const struct seccomp_data *sd)
 779{
 780        int mode = current->seccomp.mode;
 781        int this_syscall;
 782
 783        if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) &&
 784            unlikely(current->ptrace & PT_SUSPEND_SECCOMP))
 785                return 0;
 786
 787        this_syscall = sd ? sd->nr :
 788                syscall_get_nr(current, task_pt_regs(current));
 789
 790        switch (mode) {
 791        case SECCOMP_MODE_STRICT:
 792                __secure_computing_strict(this_syscall);  /* may call do_exit */
 793                return 0;
 794        case SECCOMP_MODE_FILTER:
 795                return __seccomp_filter(this_syscall, sd, false);
 796        default:
 797                BUG();
 798        }
 799}
 800#endif /* CONFIG_HAVE_ARCH_SECCOMP_FILTER */
 801
 802long prctl_get_seccomp(void)
 803{
 804        return current->seccomp.mode;
 805}
 806
 807/**
 808 * seccomp_set_mode_strict: internal function for setting strict seccomp
 809 *
 810 * Once current->seccomp.mode is non-zero, it may not be changed.
 811 *
 812 * Returns 0 on success or -EINVAL on failure.
 813 */
 814static long seccomp_set_mode_strict(void)
 815{
 816        const unsigned long seccomp_mode = SECCOMP_MODE_STRICT;
 817        long ret = -EINVAL;
 818
 819        spin_lock_irq(&current->sighand->siglock);
 820
 821        if (!seccomp_may_assign_mode(seccomp_mode))
 822                goto out;
 823
 824#ifdef TIF_NOTSC
 825        disable_TSC();
 826#endif
 827        seccomp_assign_mode(current, seccomp_mode, 0);
 828        ret = 0;
 829
 830out:
 831        spin_unlock_irq(&current->sighand->siglock);
 832
 833        return ret;
 834}
 835
 836#ifdef CONFIG_SECCOMP_FILTER
 837/**
 838 * seccomp_set_mode_filter: internal function for setting seccomp filter
 839 * @flags:  flags to change filter behavior
 840 * @filter: struct sock_fprog containing filter
 841 *
 842 * This function may be called repeatedly to install additional filters.
 843 * Every filter successfully installed will be evaluated (in reverse order)
 844 * for each system call the task makes.
 845 *
 846 * Once current->seccomp.mode is non-zero, it may not be changed.
 847 *
 848 * Returns 0 on success or -EINVAL on failure.
 849 */
 850static long seccomp_set_mode_filter(unsigned int flags,
 851                                    const char __user *filter)
 852{
 853        const unsigned long seccomp_mode = SECCOMP_MODE_FILTER;
 854        struct seccomp_filter *prepared = NULL;
 855        long ret = -EINVAL;
 856
 857        /* Validate flags. */
 858        if (flags & ~SECCOMP_FILTER_FLAG_MASK)
 859                return -EINVAL;
 860
 861        /* Prepare the new filter before holding any locks. */
 862        prepared = seccomp_prepare_user_filter(filter);
 863        if (IS_ERR(prepared))
 864                return PTR_ERR(prepared);
 865
 866        /*
 867         * Make sure we cannot change seccomp or nnp state via TSYNC
 868         * while another thread is in the middle of calling exec.
 869         */
 870        if (flags & SECCOMP_FILTER_FLAG_TSYNC &&
 871            mutex_lock_killable(&current->signal->cred_guard_mutex))
 872                goto out_free;
 873
 874        spin_lock_irq(&current->sighand->siglock);
 875
 876        if (!seccomp_may_assign_mode(seccomp_mode))
 877                goto out;
 878
 879        ret = seccomp_attach_filter(flags, prepared);
 880        if (ret)
 881                goto out;
 882        /* Do not free the successfully attached filter. */
 883        prepared = NULL;
 884
 885        seccomp_assign_mode(current, seccomp_mode, flags);
 886out:
 887        spin_unlock_irq(&current->sighand->siglock);
 888        if (flags & SECCOMP_FILTER_FLAG_TSYNC)
 889                mutex_unlock(&current->signal->cred_guard_mutex);
 890out_free:
 891        seccomp_filter_free(prepared);
 892        return ret;
 893}
 894#else
 895static inline long seccomp_set_mode_filter(unsigned int flags,
 896                                           const char __user *filter)
 897{
 898        return -EINVAL;
 899}
 900#endif
 901
 902static long seccomp_get_action_avail(const char __user *uaction)
 903{
 904        u32 action;
 905
 906        if (copy_from_user(&action, uaction, sizeof(action)))
 907                return -EFAULT;
 908
 909        switch (action) {
 910        case SECCOMP_RET_KILL_PROCESS:
 911        case SECCOMP_RET_KILL_THREAD:
 912        case SECCOMP_RET_TRAP:
 913        case SECCOMP_RET_ERRNO:
 914        case SECCOMP_RET_TRACE:
 915        case SECCOMP_RET_LOG:
 916        case SECCOMP_RET_ALLOW:
 917                break;
 918        default:
 919                return -EOPNOTSUPP;
 920        }
 921
 922        return 0;
 923}
 924
 925/* Common entry point for both prctl and syscall. */
 926static long do_seccomp(unsigned int op, unsigned int flags,
 927                       const char __user *uargs)
 928{
 929        switch (op) {
 930        case SECCOMP_SET_MODE_STRICT:
 931                if (flags != 0 || uargs != NULL)
 932                        return -EINVAL;
 933                return seccomp_set_mode_strict();
 934        case SECCOMP_SET_MODE_FILTER:
 935                return seccomp_set_mode_filter(flags, uargs);
 936        case SECCOMP_GET_ACTION_AVAIL:
 937                if (flags != 0)
 938                        return -EINVAL;
 939
 940                return seccomp_get_action_avail(uargs);
 941        default:
 942                return -EINVAL;
 943        }
 944}
 945
 946SYSCALL_DEFINE3(seccomp, unsigned int, op, unsigned int, flags,
 947                         const char __user *, uargs)
 948{
 949        return do_seccomp(op, flags, uargs);
 950}
 951
 952/**
 953 * prctl_set_seccomp: configures current->seccomp.mode
 954 * @seccomp_mode: requested mode to use
 955 * @filter: optional struct sock_fprog for use with SECCOMP_MODE_FILTER
 956 *
 957 * Returns 0 on success or -EINVAL on failure.
 958 */
 959long prctl_set_seccomp(unsigned long seccomp_mode, char __user *filter)
 960{
 961        unsigned int op;
 962        char __user *uargs;
 963
 964        switch (seccomp_mode) {
 965        case SECCOMP_MODE_STRICT:
 966                op = SECCOMP_SET_MODE_STRICT;
 967                /*
 968                 * Setting strict mode through prctl always ignored filter,
 969                 * so make sure it is always NULL here to pass the internal
 970                 * check in do_seccomp().
 971                 */
 972                uargs = NULL;
 973                break;
 974        case SECCOMP_MODE_FILTER:
 975                op = SECCOMP_SET_MODE_FILTER;
 976                uargs = filter;
 977                break;
 978        default:
 979                return -EINVAL;
 980        }
 981
 982        /* prctl interface doesn't have flags, so they are always zero. */
 983        return do_seccomp(op, 0, uargs);
 984}
 985
 986#if defined(CONFIG_SECCOMP_FILTER) && defined(CONFIG_CHECKPOINT_RESTORE)
 987static struct seccomp_filter *get_nth_filter(struct task_struct *task,
 988                                             unsigned long filter_off)
 989{
 990        struct seccomp_filter *orig, *filter;
 991        unsigned long count;
 992
 993        /*
 994         * Note: this is only correct because the caller should be the (ptrace)
 995         * tracer of the task, otherwise lock_task_sighand is needed.
 996         */
 997        spin_lock_irq(&task->sighand->siglock);
 998
 999        if (task->seccomp.mode != SECCOMP_MODE_FILTER) {
1000                spin_unlock_irq(&task->sighand->siglock);
1001                return ERR_PTR(-EINVAL);
1002        }
1003
1004        orig = task->seccomp.filter;
1005        __get_seccomp_filter(orig);
1006        spin_unlock_irq(&task->sighand->siglock);
1007
1008        count = 0;
1009        for (filter = orig; filter; filter = filter->prev)
1010                count++;
1011
1012        if (filter_off >= count) {
1013                filter = ERR_PTR(-ENOENT);
1014                goto out;
1015        }
1016
1017        count -= filter_off;
1018        for (filter = orig; filter && count > 1; filter = filter->prev)
1019                count--;
1020
1021        if (WARN_ON(count != 1 || !filter)) {
1022                filter = ERR_PTR(-ENOENT);
1023                goto out;
1024        }
1025
1026        __get_seccomp_filter(filter);
1027
1028out:
1029        __put_seccomp_filter(orig);
1030        return filter;
1031}
1032
1033long seccomp_get_filter(struct task_struct *task, unsigned long filter_off,
1034                        void __user *data)
1035{
1036        struct seccomp_filter *filter;
1037        struct sock_fprog_kern *fprog;
1038        long ret;
1039
1040        if (!capable(CAP_SYS_ADMIN) ||
1041            current->seccomp.mode != SECCOMP_MODE_DISABLED) {
1042                return -EACCES;
1043        }
1044
1045        filter = get_nth_filter(task, filter_off);
1046        if (IS_ERR(filter))
1047                return PTR_ERR(filter);
1048
1049        fprog = filter->prog->orig_prog;
1050        if (!fprog) {
1051                /* This must be a new non-cBPF filter, since we save
1052                 * every cBPF filter's orig_prog above when
1053                 * CONFIG_CHECKPOINT_RESTORE is enabled.
1054                 */
1055                ret = -EMEDIUMTYPE;
1056                goto out;
1057        }
1058
1059        ret = fprog->len;
1060        if (!data)
1061                goto out;
1062
1063        if (copy_to_user(data, fprog->filter, bpf_classic_proglen(fprog)))
1064                ret = -EFAULT;
1065
1066out:
1067        __put_seccomp_filter(filter);
1068        return ret;
1069}
1070
1071long seccomp_get_metadata(struct task_struct *task,
1072                          unsigned long size, void __user *data)
1073{
1074        long ret;
1075        struct seccomp_filter *filter;
1076        struct seccomp_metadata kmd = {};
1077
1078        if (!capable(CAP_SYS_ADMIN) ||
1079            current->seccomp.mode != SECCOMP_MODE_DISABLED) {
1080                return -EACCES;
1081        }
1082
1083        size = min_t(unsigned long, size, sizeof(kmd));
1084
1085        if (size < sizeof(kmd.filter_off))
1086                return -EINVAL;
1087
1088        if (copy_from_user(&kmd.filter_off, data, sizeof(kmd.filter_off)))
1089                return -EFAULT;
1090
1091        filter = get_nth_filter(task, kmd.filter_off);
1092        if (IS_ERR(filter))
1093                return PTR_ERR(filter);
1094
1095        if (filter->log)
1096                kmd.flags |= SECCOMP_FILTER_FLAG_LOG;
1097
1098        ret = size;
1099        if (copy_to_user(data, &kmd, size))
1100                ret = -EFAULT;
1101
1102        __put_seccomp_filter(filter);
1103        return ret;
1104}
1105#endif
1106
1107#ifdef CONFIG_SYSCTL
1108
1109/* Human readable action names for friendly sysctl interaction */
1110#define SECCOMP_RET_KILL_PROCESS_NAME   "kill_process"
1111#define SECCOMP_RET_KILL_THREAD_NAME    "kill_thread"
1112#define SECCOMP_RET_TRAP_NAME           "trap"
1113#define SECCOMP_RET_ERRNO_NAME          "errno"
1114#define SECCOMP_RET_TRACE_NAME          "trace"
1115#define SECCOMP_RET_LOG_NAME            "log"
1116#define SECCOMP_RET_ALLOW_NAME          "allow"
1117
1118static const char seccomp_actions_avail[] =
1119                                SECCOMP_RET_KILL_PROCESS_NAME   " "
1120                                SECCOMP_RET_KILL_THREAD_NAME    " "
1121                                SECCOMP_RET_TRAP_NAME           " "
1122                                SECCOMP_RET_ERRNO_NAME          " "
1123                                SECCOMP_RET_TRACE_NAME          " "
1124                                SECCOMP_RET_LOG_NAME            " "
1125                                SECCOMP_RET_ALLOW_NAME;
1126
1127struct seccomp_log_name {
1128        u32             log;
1129        const char      *name;
1130};
1131
1132static const struct seccomp_log_name seccomp_log_names[] = {
1133        { SECCOMP_LOG_KILL_PROCESS, SECCOMP_RET_KILL_PROCESS_NAME },
1134        { SECCOMP_LOG_KILL_THREAD, SECCOMP_RET_KILL_THREAD_NAME },
1135        { SECCOMP_LOG_TRAP, SECCOMP_RET_TRAP_NAME },
1136        { SECCOMP_LOG_ERRNO, SECCOMP_RET_ERRNO_NAME },
1137        { SECCOMP_LOG_TRACE, SECCOMP_RET_TRACE_NAME },
1138        { SECCOMP_LOG_LOG, SECCOMP_RET_LOG_NAME },
1139        { SECCOMP_LOG_ALLOW, SECCOMP_RET_ALLOW_NAME },
1140        { }
1141};
1142
1143static bool seccomp_names_from_actions_logged(char *names, size_t size,
1144                                              u32 actions_logged,
1145                                              const char *sep)
1146{
1147        const struct seccomp_log_name *cur;
1148        bool append_sep = false;
1149
1150        for (cur = seccomp_log_names; cur->name && size; cur++) {
1151                ssize_t ret;
1152
1153                if (!(actions_logged & cur->log))
1154                        continue;
1155
1156                if (append_sep) {
1157                        ret = strscpy(names, sep, size);
1158                        if (ret < 0)
1159                                return false;
1160
1161                        names += ret;
1162                        size -= ret;
1163                } else
1164                        append_sep = true;
1165
1166                ret = strscpy(names, cur->name, size);
1167                if (ret < 0)
1168                        return false;
1169
1170                names += ret;
1171                size -= ret;
1172        }
1173
1174        return true;
1175}
1176
1177static bool seccomp_action_logged_from_name(u32 *action_logged,
1178                                            const char *name)
1179{
1180        const struct seccomp_log_name *cur;
1181
1182        for (cur = seccomp_log_names; cur->name; cur++) {
1183                if (!strcmp(cur->name, name)) {
1184                        *action_logged = cur->log;
1185                        return true;
1186                }
1187        }
1188
1189        return false;
1190}
1191
1192static bool seccomp_actions_logged_from_names(u32 *actions_logged, char *names)
1193{
1194        char *name;
1195
1196        *actions_logged = 0;
1197        while ((name = strsep(&names, " ")) && *name) {
1198                u32 action_logged = 0;
1199
1200                if (!seccomp_action_logged_from_name(&action_logged, name))
1201                        return false;
1202
1203                *actions_logged |= action_logged;
1204        }
1205
1206        return true;
1207}
1208
1209static int read_actions_logged(struct ctl_table *ro_table, void __user *buffer,
1210                               size_t *lenp, loff_t *ppos)
1211{
1212        char names[sizeof(seccomp_actions_avail)];
1213        struct ctl_table table;
1214
1215        memset(names, 0, sizeof(names));
1216
1217        if (!seccomp_names_from_actions_logged(names, sizeof(names),
1218                                               seccomp_actions_logged, " "))
1219                return -EINVAL;
1220
1221        table = *ro_table;
1222        table.data = names;
1223        table.maxlen = sizeof(names);
1224        return proc_dostring(&table, 0, buffer, lenp, ppos);
1225}
1226
1227static int write_actions_logged(struct ctl_table *ro_table, void __user *buffer,
1228                                size_t *lenp, loff_t *ppos, u32 *actions_logged)
1229{
1230        char names[sizeof(seccomp_actions_avail)];
1231        struct ctl_table table;
1232        int ret;
1233
1234        if (!capable(CAP_SYS_ADMIN))
1235                return -EPERM;
1236
1237        memset(names, 0, sizeof(names));
1238
1239        table = *ro_table;
1240        table.data = names;
1241        table.maxlen = sizeof(names);
1242        ret = proc_dostring(&table, 1, buffer, lenp, ppos);
1243        if (ret)
1244                return ret;
1245
1246        if (!seccomp_actions_logged_from_names(actions_logged, table.data))
1247                return -EINVAL;
1248
1249        if (*actions_logged & SECCOMP_LOG_ALLOW)
1250                return -EINVAL;
1251
1252        seccomp_actions_logged = *actions_logged;
1253        return 0;
1254}
1255
1256static void audit_actions_logged(u32 actions_logged, u32 old_actions_logged,
1257                                 int ret)
1258{
1259        char names[sizeof(seccomp_actions_avail)];
1260        char old_names[sizeof(seccomp_actions_avail)];
1261        const char *new = names;
1262        const char *old = old_names;
1263
1264        if (!audit_enabled)
1265                return;
1266
1267        memset(names, 0, sizeof(names));
1268        memset(old_names, 0, sizeof(old_names));
1269
1270        if (ret)
1271                new = "?";
1272        else if (!actions_logged)
1273                new = "(none)";
1274        else if (!seccomp_names_from_actions_logged(names, sizeof(names),
1275                                                    actions_logged, ","))
1276                new = "?";
1277
1278        if (!old_actions_logged)
1279                old = "(none)";
1280        else if (!seccomp_names_from_actions_logged(old_names,
1281                                                    sizeof(old_names),
1282                                                    old_actions_logged, ","))
1283                old = "?";
1284
1285        return audit_seccomp_actions_logged(new, old, !ret);
1286}
1287
1288static int seccomp_actions_logged_handler(struct ctl_table *ro_table, int write,
1289                                          void __user *buffer, size_t *lenp,
1290                                          loff_t *ppos)
1291{
1292        int ret;
1293
1294        if (write) {
1295                u32 actions_logged = 0;
1296                u32 old_actions_logged = seccomp_actions_logged;
1297
1298                ret = write_actions_logged(ro_table, buffer, lenp, ppos,
1299                                           &actions_logged);
1300                audit_actions_logged(actions_logged, old_actions_logged, ret);
1301        } else
1302                ret = read_actions_logged(ro_table, buffer, lenp, ppos);
1303
1304        return ret;
1305}
1306
1307static struct ctl_path seccomp_sysctl_path[] = {
1308        { .procname = "kernel", },
1309        { .procname = "seccomp", },
1310        { }
1311};
1312
1313static struct ctl_table seccomp_sysctl_table[] = {
1314        {
1315                .procname       = "actions_avail",
1316                .data           = (void *) &seccomp_actions_avail,
1317                .maxlen         = sizeof(seccomp_actions_avail),
1318                .mode           = 0444,
1319                .proc_handler   = proc_dostring,
1320        },
1321        {
1322                .procname       = "actions_logged",
1323                .mode           = 0644,
1324                .proc_handler   = seccomp_actions_logged_handler,
1325        },
1326        { }
1327};
1328
1329static int __init seccomp_sysctl_init(void)
1330{
1331        struct ctl_table_header *hdr;
1332
1333        hdr = register_sysctl_paths(seccomp_sysctl_path, seccomp_sysctl_table);
1334        if (!hdr)
1335                pr_warn("seccomp: sysctl registration failed\n");
1336        else
1337                kmemleak_not_leak(hdr);
1338
1339        return 0;
1340}
1341
1342device_initcall(seccomp_sysctl_init)
1343
1344#endif /* CONFIG_SYSCTL */
1345