linux/kernel/auditsc.c
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   1/* auditsc.c -- System-call auditing support
   2 * Handles all system-call specific auditing features.
   3 *
   4 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
   5 * Copyright 2005 Hewlett-Packard Development Company, L.P.
   6 * Copyright (C) 2005, 2006 IBM Corporation
   7 * All Rights Reserved.
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License as published by
  11 * the Free Software Foundation; either version 2 of the License, or
  12 * (at your option) any later version.
  13 *
  14 * This program is distributed in the hope that it will be useful,
  15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 * GNU General Public License for more details.
  18 *
  19 * You should have received a copy of the GNU General Public License
  20 * along with this program; if not, write to the Free Software
  21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  22 *
  23 * Written by Rickard E. (Rik) Faith <faith@redhat.com>
  24 *
  25 * Many of the ideas implemented here are from Stephen C. Tweedie,
  26 * especially the idea of avoiding a copy by using getname.
  27 *
  28 * The method for actual interception of syscall entry and exit (not in
  29 * this file -- see entry.S) is based on a GPL'd patch written by
  30 * okir@suse.de and Copyright 2003 SuSE Linux AG.
  31 *
  32 * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
  33 * 2006.
  34 *
  35 * The support of additional filter rules compares (>, <, >=, <=) was
  36 * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
  37 *
  38 * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
  39 * filesystem information.
  40 *
  41 * Subject and object context labeling support added by <danjones@us.ibm.com>
  42 * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
  43 */
  44
  45#include <linux/init.h>
  46#include <asm/types.h>
  47#include <linux/atomic.h>
  48#include <linux/fs.h>
  49#include <linux/namei.h>
  50#include <linux/mm.h>
  51#include <linux/export.h>
  52#include <linux/slab.h>
  53#include <linux/mount.h>
  54#include <linux/socket.h>
  55#include <linux/mqueue.h>
  56#include <linux/audit.h>
  57#include <linux/personality.h>
  58#include <linux/time.h>
  59#include <linux/netlink.h>
  60#include <linux/compiler.h>
  61#include <asm/unistd.h>
  62#include <linux/security.h>
  63#include <linux/list.h>
  64#include <linux/tty.h>
  65#include <linux/binfmts.h>
  66#include <linux/highmem.h>
  67#include <linux/syscalls.h>
  68#include <linux/capability.h>
  69#include <linux/fs_struct.h>
  70#include <linux/compat.h>
  71
  72#include "audit.h"
  73
  74/* flags stating the success for a syscall */
  75#define AUDITSC_INVALID 0
  76#define AUDITSC_SUCCESS 1
  77#define AUDITSC_FAILURE 2
  78
  79/* no execve audit message should be longer than this (userspace limits) */
  80#define MAX_EXECVE_AUDIT_LEN 7500
  81
  82/* number of audit rules */
  83int audit_n_rules;
  84
  85/* determines whether we collect data for signals sent */
  86int audit_signals;
  87
  88struct audit_aux_data {
  89        struct audit_aux_data   *next;
  90        int                     type;
  91};
  92
  93#define AUDIT_AUX_IPCPERM       0
  94
  95/* Number of target pids per aux struct. */
  96#define AUDIT_AUX_PIDS  16
  97
  98struct audit_aux_data_execve {
  99        struct audit_aux_data   d;
 100        int argc;
 101        int envc;
 102        struct mm_struct *mm;
 103};
 104
 105struct audit_aux_data_pids {
 106        struct audit_aux_data   d;
 107        pid_t                   target_pid[AUDIT_AUX_PIDS];
 108        kuid_t                  target_auid[AUDIT_AUX_PIDS];
 109        kuid_t                  target_uid[AUDIT_AUX_PIDS];
 110        unsigned int            target_sessionid[AUDIT_AUX_PIDS];
 111        u32                     target_sid[AUDIT_AUX_PIDS];
 112        char                    target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
 113        int                     pid_count;
 114};
 115
 116struct audit_aux_data_bprm_fcaps {
 117        struct audit_aux_data   d;
 118        struct audit_cap_data   fcap;
 119        unsigned int            fcap_ver;
 120        struct audit_cap_data   old_pcap;
 121        struct audit_cap_data   new_pcap;
 122};
 123
 124struct audit_aux_data_capset {
 125        struct audit_aux_data   d;
 126        pid_t                   pid;
 127        struct audit_cap_data   cap;
 128};
 129
 130struct audit_tree_refs {
 131        struct audit_tree_refs *next;
 132        struct audit_chunk *c[31];
 133};
 134
 135static inline int open_arg(int flags, int mask)
 136{
 137        int n = ACC_MODE(flags);
 138        if (flags & (O_TRUNC | O_CREAT))
 139                n |= AUDIT_PERM_WRITE;
 140        return n & mask;
 141}
 142
 143static int audit_match_perm(struct audit_context *ctx, int mask)
 144{
 145        unsigned n;
 146        if (unlikely(!ctx))
 147                return 0;
 148        n = ctx->major;
 149
 150        switch (audit_classify_syscall(ctx->arch, n)) {
 151        case 0: /* native */
 152                if ((mask & AUDIT_PERM_WRITE) &&
 153                     audit_match_class(AUDIT_CLASS_WRITE, n))
 154                        return 1;
 155                if ((mask & AUDIT_PERM_READ) &&
 156                     audit_match_class(AUDIT_CLASS_READ, n))
 157                        return 1;
 158                if ((mask & AUDIT_PERM_ATTR) &&
 159                     audit_match_class(AUDIT_CLASS_CHATTR, n))
 160                        return 1;
 161                return 0;
 162        case 1: /* 32bit on biarch */
 163                if ((mask & AUDIT_PERM_WRITE) &&
 164                     audit_match_class(AUDIT_CLASS_WRITE_32, n))
 165                        return 1;
 166                if ((mask & AUDIT_PERM_READ) &&
 167                     audit_match_class(AUDIT_CLASS_READ_32, n))
 168                        return 1;
 169                if ((mask & AUDIT_PERM_ATTR) &&
 170                     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
 171                        return 1;
 172                return 0;
 173        case 2: /* open */
 174                return mask & ACC_MODE(ctx->argv[1]);
 175        case 3: /* openat */
 176                return mask & ACC_MODE(ctx->argv[2]);
 177        case 4: /* socketcall */
 178                return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
 179        case 5: /* execve */
 180                return mask & AUDIT_PERM_EXEC;
 181        default:
 182                return 0;
 183        }
 184}
 185
 186static int audit_match_filetype(struct audit_context *ctx, int val)
 187{
 188        struct audit_names *n;
 189        umode_t mode = (umode_t)val;
 190
 191        if (unlikely(!ctx))
 192                return 0;
 193
 194        list_for_each_entry(n, &ctx->names_list, list) {
 195                if ((n->ino != -1) &&
 196                    ((n->mode & S_IFMT) == mode))
 197                        return 1;
 198        }
 199
 200        return 0;
 201}
 202
 203/*
 204 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
 205 * ->first_trees points to its beginning, ->trees - to the current end of data.
 206 * ->tree_count is the number of free entries in array pointed to by ->trees.
 207 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
 208 * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
 209 * it's going to remain 1-element for almost any setup) until we free context itself.
 210 * References in it _are_ dropped - at the same time we free/drop aux stuff.
 211 */
 212
 213#ifdef CONFIG_AUDIT_TREE
 214static void audit_set_auditable(struct audit_context *ctx)
 215{
 216        if (!ctx->prio) {
 217                ctx->prio = 1;
 218                ctx->current_state = AUDIT_RECORD_CONTEXT;
 219        }
 220}
 221
 222static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
 223{
 224        struct audit_tree_refs *p = ctx->trees;
 225        int left = ctx->tree_count;
 226        if (likely(left)) {
 227                p->c[--left] = chunk;
 228                ctx->tree_count = left;
 229                return 1;
 230        }
 231        if (!p)
 232                return 0;
 233        p = p->next;
 234        if (p) {
 235                p->c[30] = chunk;
 236                ctx->trees = p;
 237                ctx->tree_count = 30;
 238                return 1;
 239        }
 240        return 0;
 241}
 242
 243static int grow_tree_refs(struct audit_context *ctx)
 244{
 245        struct audit_tree_refs *p = ctx->trees;
 246        ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
 247        if (!ctx->trees) {
 248                ctx->trees = p;
 249                return 0;
 250        }
 251        if (p)
 252                p->next = ctx->trees;
 253        else
 254                ctx->first_trees = ctx->trees;
 255        ctx->tree_count = 31;
 256        return 1;
 257}
 258#endif
 259
 260static void unroll_tree_refs(struct audit_context *ctx,
 261                      struct audit_tree_refs *p, int count)
 262{
 263#ifdef CONFIG_AUDIT_TREE
 264        struct audit_tree_refs *q;
 265        int n;
 266        if (!p) {
 267                /* we started with empty chain */
 268                p = ctx->first_trees;
 269                count = 31;
 270                /* if the very first allocation has failed, nothing to do */
 271                if (!p)
 272                        return;
 273        }
 274        n = count;
 275        for (q = p; q != ctx->trees; q = q->next, n = 31) {
 276                while (n--) {
 277                        audit_put_chunk(q->c[n]);
 278                        q->c[n] = NULL;
 279                }
 280        }
 281        while (n-- > ctx->tree_count) {
 282                audit_put_chunk(q->c[n]);
 283                q->c[n] = NULL;
 284        }
 285        ctx->trees = p;
 286        ctx->tree_count = count;
 287#endif
 288}
 289
 290static void free_tree_refs(struct audit_context *ctx)
 291{
 292        struct audit_tree_refs *p, *q;
 293        for (p = ctx->first_trees; p; p = q) {
 294                q = p->next;
 295                kfree(p);
 296        }
 297}
 298
 299static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
 300{
 301#ifdef CONFIG_AUDIT_TREE
 302        struct audit_tree_refs *p;
 303        int n;
 304        if (!tree)
 305                return 0;
 306        /* full ones */
 307        for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
 308                for (n = 0; n < 31; n++)
 309                        if (audit_tree_match(p->c[n], tree))
 310                                return 1;
 311        }
 312        /* partial */
 313        if (p) {
 314                for (n = ctx->tree_count; n < 31; n++)
 315                        if (audit_tree_match(p->c[n], tree))
 316                                return 1;
 317        }
 318#endif
 319        return 0;
 320}
 321
 322static int audit_compare_uid(kuid_t uid,
 323                             struct audit_names *name,
 324                             struct audit_field *f,
 325                             struct audit_context *ctx)
 326{
 327        struct audit_names *n;
 328        int rc;
 329 
 330        if (name) {
 331                rc = audit_uid_comparator(uid, f->op, name->uid);
 332                if (rc)
 333                        return rc;
 334        }
 335 
 336        if (ctx) {
 337                list_for_each_entry(n, &ctx->names_list, list) {
 338                        rc = audit_uid_comparator(uid, f->op, n->uid);
 339                        if (rc)
 340                                return rc;
 341                }
 342        }
 343        return 0;
 344}
 345
 346static int audit_compare_gid(kgid_t gid,
 347                             struct audit_names *name,
 348                             struct audit_field *f,
 349                             struct audit_context *ctx)
 350{
 351        struct audit_names *n;
 352        int rc;
 353 
 354        if (name) {
 355                rc = audit_gid_comparator(gid, f->op, name->gid);
 356                if (rc)
 357                        return rc;
 358        }
 359 
 360        if (ctx) {
 361                list_for_each_entry(n, &ctx->names_list, list) {
 362                        rc = audit_gid_comparator(gid, f->op, n->gid);
 363                        if (rc)
 364                                return rc;
 365                }
 366        }
 367        return 0;
 368}
 369
 370static int audit_field_compare(struct task_struct *tsk,
 371                               const struct cred *cred,
 372                               struct audit_field *f,
 373                               struct audit_context *ctx,
 374                               struct audit_names *name)
 375{
 376        switch (f->val) {
 377        /* process to file object comparisons */
 378        case AUDIT_COMPARE_UID_TO_OBJ_UID:
 379                return audit_compare_uid(cred->uid, name, f, ctx);
 380        case AUDIT_COMPARE_GID_TO_OBJ_GID:
 381                return audit_compare_gid(cred->gid, name, f, ctx);
 382        case AUDIT_COMPARE_EUID_TO_OBJ_UID:
 383                return audit_compare_uid(cred->euid, name, f, ctx);
 384        case AUDIT_COMPARE_EGID_TO_OBJ_GID:
 385                return audit_compare_gid(cred->egid, name, f, ctx);
 386        case AUDIT_COMPARE_AUID_TO_OBJ_UID:
 387                return audit_compare_uid(tsk->loginuid, name, f, ctx);
 388        case AUDIT_COMPARE_SUID_TO_OBJ_UID:
 389                return audit_compare_uid(cred->suid, name, f, ctx);
 390        case AUDIT_COMPARE_SGID_TO_OBJ_GID:
 391                return audit_compare_gid(cred->sgid, name, f, ctx);
 392        case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
 393                return audit_compare_uid(cred->fsuid, name, f, ctx);
 394        case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
 395                return audit_compare_gid(cred->fsgid, name, f, ctx);
 396        /* uid comparisons */
 397        case AUDIT_COMPARE_UID_TO_AUID:
 398                return audit_uid_comparator(cred->uid, f->op, tsk->loginuid);
 399        case AUDIT_COMPARE_UID_TO_EUID:
 400                return audit_uid_comparator(cred->uid, f->op, cred->euid);
 401        case AUDIT_COMPARE_UID_TO_SUID:
 402                return audit_uid_comparator(cred->uid, f->op, cred->suid);
 403        case AUDIT_COMPARE_UID_TO_FSUID:
 404                return audit_uid_comparator(cred->uid, f->op, cred->fsuid);
 405        /* auid comparisons */
 406        case AUDIT_COMPARE_AUID_TO_EUID:
 407                return audit_uid_comparator(tsk->loginuid, f->op, cred->euid);
 408        case AUDIT_COMPARE_AUID_TO_SUID:
 409                return audit_uid_comparator(tsk->loginuid, f->op, cred->suid);
 410        case AUDIT_COMPARE_AUID_TO_FSUID:
 411                return audit_uid_comparator(tsk->loginuid, f->op, cred->fsuid);
 412        /* euid comparisons */
 413        case AUDIT_COMPARE_EUID_TO_SUID:
 414                return audit_uid_comparator(cred->euid, f->op, cred->suid);
 415        case AUDIT_COMPARE_EUID_TO_FSUID:
 416                return audit_uid_comparator(cred->euid, f->op, cred->fsuid);
 417        /* suid comparisons */
 418        case AUDIT_COMPARE_SUID_TO_FSUID:
 419                return audit_uid_comparator(cred->suid, f->op, cred->fsuid);
 420        /* gid comparisons */
 421        case AUDIT_COMPARE_GID_TO_EGID:
 422                return audit_gid_comparator(cred->gid, f->op, cred->egid);
 423        case AUDIT_COMPARE_GID_TO_SGID:
 424                return audit_gid_comparator(cred->gid, f->op, cred->sgid);
 425        case AUDIT_COMPARE_GID_TO_FSGID:
 426                return audit_gid_comparator(cred->gid, f->op, cred->fsgid);
 427        /* egid comparisons */
 428        case AUDIT_COMPARE_EGID_TO_SGID:
 429                return audit_gid_comparator(cred->egid, f->op, cred->sgid);
 430        case AUDIT_COMPARE_EGID_TO_FSGID:
 431                return audit_gid_comparator(cred->egid, f->op, cred->fsgid);
 432        /* sgid comparison */
 433        case AUDIT_COMPARE_SGID_TO_FSGID:
 434                return audit_gid_comparator(cred->sgid, f->op, cred->fsgid);
 435        default:
 436                WARN(1, "Missing AUDIT_COMPARE define.  Report as a bug\n");
 437                return 0;
 438        }
 439        return 0;
 440}
 441
 442/* Determine if any context name data matches a rule's watch data */
 443/* Compare a task_struct with an audit_rule.  Return 1 on match, 0
 444 * otherwise.
 445 *
 446 * If task_creation is true, this is an explicit indication that we are
 447 * filtering a task rule at task creation time.  This and tsk == current are
 448 * the only situations where tsk->cred may be accessed without an rcu read lock.
 449 */
 450static int audit_filter_rules(struct task_struct *tsk,
 451                              struct audit_krule *rule,
 452                              struct audit_context *ctx,
 453                              struct audit_names *name,
 454                              enum audit_state *state,
 455                              bool task_creation)
 456{
 457        const struct cred *cred;
 458        int i, need_sid = 1;
 459        u32 sid;
 460
 461        cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
 462
 463        for (i = 0; i < rule->field_count; i++) {
 464                struct audit_field *f = &rule->fields[i];
 465                struct audit_names *n;
 466                int result = 0;
 467
 468                switch (f->type) {
 469                case AUDIT_PID:
 470                        result = audit_comparator(tsk->pid, f->op, f->val);
 471                        break;
 472                case AUDIT_PPID:
 473                        if (ctx) {
 474                                if (!ctx->ppid)
 475                                        ctx->ppid = sys_getppid();
 476                                result = audit_comparator(ctx->ppid, f->op, f->val);
 477                        }
 478                        break;
 479                case AUDIT_UID:
 480                        result = audit_uid_comparator(cred->uid, f->op, f->uid);
 481                        break;
 482                case AUDIT_EUID:
 483                        result = audit_uid_comparator(cred->euid, f->op, f->uid);
 484                        break;
 485                case AUDIT_SUID:
 486                        result = audit_uid_comparator(cred->suid, f->op, f->uid);
 487                        break;
 488                case AUDIT_FSUID:
 489                        result = audit_uid_comparator(cred->fsuid, f->op, f->uid);
 490                        break;
 491                case AUDIT_GID:
 492                        result = audit_gid_comparator(cred->gid, f->op, f->gid);
 493                        if (f->op == Audit_equal) {
 494                                if (!result)
 495                                        result = in_group_p(f->gid);
 496                        } else if (f->op == Audit_not_equal) {
 497                                if (result)
 498                                        result = !in_group_p(f->gid);
 499                        }
 500                        break;
 501                case AUDIT_EGID:
 502                        result = audit_gid_comparator(cred->egid, f->op, f->gid);
 503                        if (f->op == Audit_equal) {
 504                                if (!result)
 505                                        result = in_egroup_p(f->gid);
 506                        } else if (f->op == Audit_not_equal) {
 507                                if (result)
 508                                        result = !in_egroup_p(f->gid);
 509                        }
 510                        break;
 511                case AUDIT_SGID:
 512                        result = audit_gid_comparator(cred->sgid, f->op, f->gid);
 513                        break;
 514                case AUDIT_FSGID:
 515                        result = audit_gid_comparator(cred->fsgid, f->op, f->gid);
 516                        break;
 517                case AUDIT_PERS:
 518                        result = audit_comparator(tsk->personality, f->op, f->val);
 519                        break;
 520                case AUDIT_ARCH:
 521                        if (ctx)
 522                                result = audit_comparator(ctx->arch, f->op, f->val);
 523                        break;
 524
 525                case AUDIT_EXIT:
 526                        if (ctx && ctx->return_valid)
 527                                result = audit_comparator(ctx->return_code, f->op, f->val);
 528                        break;
 529                case AUDIT_SUCCESS:
 530                        if (ctx && ctx->return_valid) {
 531                                if (f->val)
 532                                        result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
 533                                else
 534                                        result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
 535                        }
 536                        break;
 537                case AUDIT_DEVMAJOR:
 538                        if (name) {
 539                                if (audit_comparator(MAJOR(name->dev), f->op, f->val) ||
 540                                    audit_comparator(MAJOR(name->rdev), f->op, f->val))
 541                                        ++result;
 542                        } else if (ctx) {
 543                                list_for_each_entry(n, &ctx->names_list, list) {
 544                                        if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
 545                                            audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
 546                                                ++result;
 547                                                break;
 548                                        }
 549                                }
 550                        }
 551                        break;
 552                case AUDIT_DEVMINOR:
 553                        if (name) {
 554                                if (audit_comparator(MINOR(name->dev), f->op, f->val) ||
 555                                    audit_comparator(MINOR(name->rdev), f->op, f->val))
 556                                        ++result;
 557                        } else if (ctx) {
 558                                list_for_each_entry(n, &ctx->names_list, list) {
 559                                        if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
 560                                            audit_comparator(MINOR(n->rdev), f->op, f->val)) {
 561                                                ++result;
 562                                                break;
 563                                        }
 564                                }
 565                        }
 566                        break;
 567                case AUDIT_INODE:
 568                        if (name)
 569                                result = (name->ino == f->val);
 570                        else if (ctx) {
 571                                list_for_each_entry(n, &ctx->names_list, list) {
 572                                        if (audit_comparator(n->ino, f->op, f->val)) {
 573                                                ++result;
 574                                                break;
 575                                        }
 576                                }
 577                        }
 578                        break;
 579                case AUDIT_OBJ_UID:
 580                        if (name) {
 581                                result = audit_uid_comparator(name->uid, f->op, f->uid);
 582                        } else if (ctx) {
 583                                list_for_each_entry(n, &ctx->names_list, list) {
 584                                        if (audit_uid_comparator(n->uid, f->op, f->uid)) {
 585                                                ++result;
 586                                                break;
 587                                        }
 588                                }
 589                        }
 590                        break;
 591                case AUDIT_OBJ_GID:
 592                        if (name) {
 593                                result = audit_gid_comparator(name->gid, f->op, f->gid);
 594                        } else if (ctx) {
 595                                list_for_each_entry(n, &ctx->names_list, list) {
 596                                        if (audit_gid_comparator(n->gid, f->op, f->gid)) {
 597                                                ++result;
 598                                                break;
 599                                        }
 600                                }
 601                        }
 602                        break;
 603                case AUDIT_WATCH:
 604                        if (name)
 605                                result = audit_watch_compare(rule->watch, name->ino, name->dev);
 606                        break;
 607                case AUDIT_DIR:
 608                        if (ctx)
 609                                result = match_tree_refs(ctx, rule->tree);
 610                        break;
 611                case AUDIT_LOGINUID:
 612                        result = 0;
 613                        if (ctx)
 614                                result = audit_uid_comparator(tsk->loginuid, f->op, f->uid);
 615                        break;
 616                case AUDIT_LOGINUID_SET:
 617                        result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val);
 618                        break;
 619                case AUDIT_SUBJ_USER:
 620                case AUDIT_SUBJ_ROLE:
 621                case AUDIT_SUBJ_TYPE:
 622                case AUDIT_SUBJ_SEN:
 623                case AUDIT_SUBJ_CLR:
 624                        /* NOTE: this may return negative values indicating
 625                           a temporary error.  We simply treat this as a
 626                           match for now to avoid losing information that
 627                           may be wanted.   An error message will also be
 628                           logged upon error */
 629                        if (f->lsm_rule) {
 630                                if (need_sid) {
 631                                        security_task_getsecid(tsk, &sid);
 632                                        need_sid = 0;
 633                                }
 634                                result = security_audit_rule_match(sid, f->type,
 635                                                                  f->op,
 636                                                                  f->lsm_rule,
 637                                                                  ctx);
 638                        }
 639                        break;
 640                case AUDIT_OBJ_USER:
 641                case AUDIT_OBJ_ROLE:
 642                case AUDIT_OBJ_TYPE:
 643                case AUDIT_OBJ_LEV_LOW:
 644                case AUDIT_OBJ_LEV_HIGH:
 645                        /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
 646                           also applies here */
 647                        if (f->lsm_rule) {
 648                                /* Find files that match */
 649                                if (name) {
 650                                        result = security_audit_rule_match(
 651                                                   name->osid, f->type, f->op,
 652                                                   f->lsm_rule, ctx);
 653                                } else if (ctx) {
 654                                        list_for_each_entry(n, &ctx->names_list, list) {
 655                                                if (security_audit_rule_match(n->osid, f->type,
 656                                                                              f->op, f->lsm_rule,
 657                                                                              ctx)) {
 658                                                        ++result;
 659                                                        break;
 660                                                }
 661                                        }
 662                                }
 663                                /* Find ipc objects that match */
 664                                if (!ctx || ctx->type != AUDIT_IPC)
 665                                        break;
 666                                if (security_audit_rule_match(ctx->ipc.osid,
 667                                                              f->type, f->op,
 668                                                              f->lsm_rule, ctx))
 669                                        ++result;
 670                        }
 671                        break;
 672                case AUDIT_ARG0:
 673                case AUDIT_ARG1:
 674                case AUDIT_ARG2:
 675                case AUDIT_ARG3:
 676                        if (ctx)
 677                                result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
 678                        break;
 679                case AUDIT_FILTERKEY:
 680                        /* ignore this field for filtering */
 681                        result = 1;
 682                        break;
 683                case AUDIT_PERM:
 684                        result = audit_match_perm(ctx, f->val);
 685                        break;
 686                case AUDIT_FILETYPE:
 687                        result = audit_match_filetype(ctx, f->val);
 688                        break;
 689                case AUDIT_FIELD_COMPARE:
 690                        result = audit_field_compare(tsk, cred, f, ctx, name);
 691                        break;
 692                }
 693                if (!result)
 694                        return 0;
 695        }
 696
 697        if (ctx) {
 698                if (rule->prio <= ctx->prio)
 699                        return 0;
 700                if (rule->filterkey) {
 701                        kfree(ctx->filterkey);
 702                        ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
 703                }
 704                ctx->prio = rule->prio;
 705        }
 706        switch (rule->action) {
 707        case AUDIT_NEVER:    *state = AUDIT_DISABLED;       break;
 708        case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
 709        }
 710        return 1;
 711}
 712
 713/* At process creation time, we can determine if system-call auditing is
 714 * completely disabled for this task.  Since we only have the task
 715 * structure at this point, we can only check uid and gid.
 716 */
 717static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
 718{
 719        struct audit_entry *e;
 720        enum audit_state   state;
 721
 722        rcu_read_lock();
 723        list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
 724                if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
 725                                       &state, true)) {
 726                        if (state == AUDIT_RECORD_CONTEXT)
 727                                *key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
 728                        rcu_read_unlock();
 729                        return state;
 730                }
 731        }
 732        rcu_read_unlock();
 733        return AUDIT_BUILD_CONTEXT;
 734}
 735
 736/* At syscall entry and exit time, this filter is called if the
 737 * audit_state is not low enough that auditing cannot take place, but is
 738 * also not high enough that we already know we have to write an audit
 739 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
 740 */
 741static enum audit_state audit_filter_syscall(struct task_struct *tsk,
 742                                             struct audit_context *ctx,
 743                                             struct list_head *list)
 744{
 745        struct audit_entry *e;
 746        enum audit_state state;
 747
 748        if (audit_pid && tsk->tgid == audit_pid)
 749                return AUDIT_DISABLED;
 750
 751        rcu_read_lock();
 752        if (!list_empty(list)) {
 753                int word = AUDIT_WORD(ctx->major);
 754                int bit  = AUDIT_BIT(ctx->major);
 755
 756                list_for_each_entry_rcu(e, list, list) {
 757                        if ((e->rule.mask[word] & bit) == bit &&
 758                            audit_filter_rules(tsk, &e->rule, ctx, NULL,
 759                                               &state, false)) {
 760                                rcu_read_unlock();
 761                                ctx->current_state = state;
 762                                return state;
 763                        }
 764                }
 765        }
 766        rcu_read_unlock();
 767        return AUDIT_BUILD_CONTEXT;
 768}
 769
 770/*
 771 * Given an audit_name check the inode hash table to see if they match.
 772 * Called holding the rcu read lock to protect the use of audit_inode_hash
 773 */
 774static int audit_filter_inode_name(struct task_struct *tsk,
 775                                   struct audit_names *n,
 776                                   struct audit_context *ctx) {
 777        int word, bit;
 778        int h = audit_hash_ino((u32)n->ino);
 779        struct list_head *list = &audit_inode_hash[h];
 780        struct audit_entry *e;
 781        enum audit_state state;
 782
 783        word = AUDIT_WORD(ctx->major);
 784        bit  = AUDIT_BIT(ctx->major);
 785
 786        if (list_empty(list))
 787                return 0;
 788
 789        list_for_each_entry_rcu(e, list, list) {
 790                if ((e->rule.mask[word] & bit) == bit &&
 791                    audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
 792                        ctx->current_state = state;
 793                        return 1;
 794                }
 795        }
 796
 797        return 0;
 798}
 799
 800/* At syscall exit time, this filter is called if any audit_names have been
 801 * collected during syscall processing.  We only check rules in sublists at hash
 802 * buckets applicable to the inode numbers in audit_names.
 803 * Regarding audit_state, same rules apply as for audit_filter_syscall().
 804 */
 805void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
 806{
 807        struct audit_names *n;
 808
 809        if (audit_pid && tsk->tgid == audit_pid)
 810                return;
 811
 812        rcu_read_lock();
 813
 814        list_for_each_entry(n, &ctx->names_list, list) {
 815                if (audit_filter_inode_name(tsk, n, ctx))
 816                        break;
 817        }
 818        rcu_read_unlock();
 819}
 820
 821static inline struct audit_context *audit_get_context(struct task_struct *tsk,
 822                                                      int return_valid,
 823                                                      long return_code)
 824{
 825        struct audit_context *context = tsk->audit_context;
 826
 827        if (!context)
 828                return NULL;
 829        context->return_valid = return_valid;
 830
 831        /*
 832         * we need to fix up the return code in the audit logs if the actual
 833         * return codes are later going to be fixed up by the arch specific
 834         * signal handlers
 835         *
 836         * This is actually a test for:
 837         * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
 838         * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
 839         *
 840         * but is faster than a bunch of ||
 841         */
 842        if (unlikely(return_code <= -ERESTARTSYS) &&
 843            (return_code >= -ERESTART_RESTARTBLOCK) &&
 844            (return_code != -ENOIOCTLCMD))
 845                context->return_code = -EINTR;
 846        else
 847                context->return_code  = return_code;
 848
 849        if (context->in_syscall && !context->dummy) {
 850                audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
 851                audit_filter_inodes(tsk, context);
 852        }
 853
 854        tsk->audit_context = NULL;
 855        return context;
 856}
 857
 858static inline void audit_free_names(struct audit_context *context)
 859{
 860        struct audit_names *n, *next;
 861
 862#if AUDIT_DEBUG == 2
 863        if (context->put_count + context->ino_count != context->name_count) {
 864                int i = 0;
 865
 866                printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
 867                       " name_count=%d put_count=%d"
 868                       " ino_count=%d [NOT freeing]\n",
 869                       __FILE__, __LINE__,
 870                       context->serial, context->major, context->in_syscall,
 871                       context->name_count, context->put_count,
 872                       context->ino_count);
 873                list_for_each_entry(n, &context->names_list, list) {
 874                        printk(KERN_ERR "names[%d] = %p = %s\n", i++,
 875                               n->name, n->name->name ?: "(null)");
 876                }
 877                dump_stack();
 878                return;
 879        }
 880#endif
 881#if AUDIT_DEBUG
 882        context->put_count  = 0;
 883        context->ino_count  = 0;
 884#endif
 885
 886        list_for_each_entry_safe(n, next, &context->names_list, list) {
 887                list_del(&n->list);
 888                if (n->name && n->name_put)
 889                        final_putname(n->name);
 890                if (n->should_free)
 891                        kfree(n);
 892        }
 893        context->name_count = 0;
 894        path_put(&context->pwd);
 895        context->pwd.dentry = NULL;
 896        context->pwd.mnt = NULL;
 897}
 898
 899static inline void audit_free_aux(struct audit_context *context)
 900{
 901        struct audit_aux_data *aux;
 902
 903        while ((aux = context->aux)) {
 904                context->aux = aux->next;
 905                kfree(aux);
 906        }
 907        while ((aux = context->aux_pids)) {
 908                context->aux_pids = aux->next;
 909                kfree(aux);
 910        }
 911}
 912
 913static inline struct audit_context *audit_alloc_context(enum audit_state state)
 914{
 915        struct audit_context *context;
 916
 917        context = kzalloc(sizeof(*context), GFP_KERNEL);
 918        if (!context)
 919                return NULL;
 920        context->state = state;
 921        context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
 922        INIT_LIST_HEAD(&context->killed_trees);
 923        INIT_LIST_HEAD(&context->names_list);
 924        return context;
 925}
 926
 927/**
 928 * audit_alloc - allocate an audit context block for a task
 929 * @tsk: task
 930 *
 931 * Filter on the task information and allocate a per-task audit context
 932 * if necessary.  Doing so turns on system call auditing for the
 933 * specified task.  This is called from copy_process, so no lock is
 934 * needed.
 935 */
 936int audit_alloc(struct task_struct *tsk)
 937{
 938        struct audit_context *context;
 939        enum audit_state     state;
 940        char *key = NULL;
 941
 942        if (likely(!audit_ever_enabled))
 943                return 0; /* Return if not auditing. */
 944
 945        state = audit_filter_task(tsk, &key);
 946        if (state == AUDIT_DISABLED)
 947                return 0;
 948
 949        if (!(context = audit_alloc_context(state))) {
 950                kfree(key);
 951                audit_log_lost("out of memory in audit_alloc");
 952                return -ENOMEM;
 953        }
 954        context->filterkey = key;
 955
 956        tsk->audit_context  = context;
 957        set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
 958        return 0;
 959}
 960
 961static inline void audit_free_context(struct audit_context *context)
 962{
 963        audit_free_names(context);
 964        unroll_tree_refs(context, NULL, 0);
 965        free_tree_refs(context);
 966        audit_free_aux(context);
 967        kfree(context->filterkey);
 968        kfree(context->sockaddr);
 969        kfree(context);
 970}
 971
 972static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 973                                 kuid_t auid, kuid_t uid, unsigned int sessionid,
 974                                 u32 sid, char *comm)
 975{
 976        struct audit_buffer *ab;
 977        char *ctx = NULL;
 978        u32 len;
 979        int rc = 0;
 980
 981        ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
 982        if (!ab)
 983                return rc;
 984
 985        audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
 986                         from_kuid(&init_user_ns, auid),
 987                         from_kuid(&init_user_ns, uid), sessionid);
 988        if (sid) {
 989                if (security_secid_to_secctx(sid, &ctx, &len)) {
 990                        audit_log_format(ab, " obj=(none)");
 991                        rc = 1;
 992                } else {
 993                        audit_log_format(ab, " obj=%s", ctx);
 994                        security_release_secctx(ctx, len);
 995                }
 996        }
 997        audit_log_format(ab, " ocomm=");
 998        audit_log_untrustedstring(ab, comm);
 999        audit_log_end(ab);
1000
1001        return rc;
1002}
1003
1004/*
1005 * to_send and len_sent accounting are very loose estimates.  We aren't
1006 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
1007 * within about 500 bytes (next page boundary)
1008 *
1009 * why snprintf?  an int is up to 12 digits long.  if we just assumed when
1010 * logging that a[%d]= was going to be 16 characters long we would be wasting
1011 * space in every audit message.  In one 7500 byte message we can log up to
1012 * about 1000 min size arguments.  That comes down to about 50% waste of space
1013 * if we didn't do the snprintf to find out how long arg_num_len was.
1014 */
1015static int audit_log_single_execve_arg(struct audit_context *context,
1016                                        struct audit_buffer **ab,
1017                                        int arg_num,
1018                                        size_t *len_sent,
1019                                        const char __user *p,
1020                                        char *buf)
1021{
1022        char arg_num_len_buf[12];
1023        const char __user *tmp_p = p;
1024        /* how many digits are in arg_num? 5 is the length of ' a=""' */
1025        size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5;
1026        size_t len, len_left, to_send;
1027        size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1028        unsigned int i, has_cntl = 0, too_long = 0;
1029        int ret;
1030
1031        /* strnlen_user includes the null we don't want to send */
1032        len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1033
1034        /*
1035         * We just created this mm, if we can't find the strings
1036         * we just copied into it something is _very_ wrong. Similar
1037         * for strings that are too long, we should not have created
1038         * any.
1039         */
1040        if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1041                WARN_ON(1);
1042                send_sig(SIGKILL, current, 0);
1043                return -1;
1044        }
1045
1046        /* walk the whole argument looking for non-ascii chars */
1047        do {
1048                if (len_left > MAX_EXECVE_AUDIT_LEN)
1049                        to_send = MAX_EXECVE_AUDIT_LEN;
1050                else
1051                        to_send = len_left;
1052                ret = copy_from_user(buf, tmp_p, to_send);
1053                /*
1054                 * There is no reason for this copy to be short. We just
1055                 * copied them here, and the mm hasn't been exposed to user-
1056                 * space yet.
1057                 */
1058                if (ret) {
1059                        WARN_ON(1);
1060                        send_sig(SIGKILL, current, 0);
1061                        return -1;
1062                }
1063                buf[to_send] = '\0';
1064                has_cntl = audit_string_contains_control(buf, to_send);
1065                if (has_cntl) {
1066                        /*
1067                         * hex messages get logged as 2 bytes, so we can only
1068                         * send half as much in each message
1069                         */
1070                        max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1071                        break;
1072                }
1073                len_left -= to_send;
1074                tmp_p += to_send;
1075        } while (len_left > 0);
1076
1077        len_left = len;
1078
1079        if (len > max_execve_audit_len)
1080                too_long = 1;
1081
1082        /* rewalk the argument actually logging the message */
1083        for (i = 0; len_left > 0; i++) {
1084                int room_left;
1085
1086                if (len_left > max_execve_audit_len)
1087                        to_send = max_execve_audit_len;
1088                else
1089                        to_send = len_left;
1090
1091                /* do we have space left to send this argument in this ab? */
1092                room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1093                if (has_cntl)
1094                        room_left -= (to_send * 2);
1095                else
1096                        room_left -= to_send;
1097                if (room_left < 0) {
1098                        *len_sent = 0;
1099                        audit_log_end(*ab);
1100                        *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1101                        if (!*ab)
1102                                return 0;
1103                }
1104
1105                /*
1106                 * first record needs to say how long the original string was
1107                 * so we can be sure nothing was lost.
1108                 */
1109                if ((i == 0) && (too_long))
1110                        audit_log_format(*ab, " a%d_len=%zu", arg_num,
1111                                         has_cntl ? 2*len : len);
1112
1113                /*
1114                 * normally arguments are small enough to fit and we already
1115                 * filled buf above when we checked for control characters
1116                 * so don't bother with another copy_from_user
1117                 */
1118                if (len >= max_execve_audit_len)
1119                        ret = copy_from_user(buf, p, to_send);
1120                else
1121                        ret = 0;
1122                if (ret) {
1123                        WARN_ON(1);
1124                        send_sig(SIGKILL, current, 0);
1125                        return -1;
1126                }
1127                buf[to_send] = '\0';
1128
1129                /* actually log it */
1130                audit_log_format(*ab, " a%d", arg_num);
1131                if (too_long)
1132                        audit_log_format(*ab, "[%d]", i);
1133                audit_log_format(*ab, "=");
1134                if (has_cntl)
1135                        audit_log_n_hex(*ab, buf, to_send);
1136                else
1137                        audit_log_string(*ab, buf);
1138
1139                p += to_send;
1140                len_left -= to_send;
1141                *len_sent += arg_num_len;
1142                if (has_cntl)
1143                        *len_sent += to_send * 2;
1144                else
1145                        *len_sent += to_send;
1146        }
1147        /* include the null we didn't log */
1148        return len + 1;
1149}
1150
1151static void audit_log_execve_info(struct audit_context *context,
1152                                  struct audit_buffer **ab,
1153                                  struct audit_aux_data_execve *axi)
1154{
1155        int i, len;
1156        size_t len_sent = 0;
1157        const char __user *p;
1158        char *buf;
1159
1160        if (axi->mm != current->mm)
1161                return; /* execve failed, no additional info */
1162
1163        p = (const char __user *)axi->mm->arg_start;
1164
1165        audit_log_format(*ab, "argc=%d", axi->argc);
1166
1167        /*
1168         * we need some kernel buffer to hold the userspace args.  Just
1169         * allocate one big one rather than allocating one of the right size
1170         * for every single argument inside audit_log_single_execve_arg()
1171         * should be <8k allocation so should be pretty safe.
1172         */
1173        buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1174        if (!buf) {
1175                audit_panic("out of memory for argv string\n");
1176                return;
1177        }
1178
1179        for (i = 0; i < axi->argc; i++) {
1180                len = audit_log_single_execve_arg(context, ab, i,
1181                                                  &len_sent, p, buf);
1182                if (len <= 0)
1183                        break;
1184                p += len;
1185        }
1186        kfree(buf);
1187}
1188
1189static void show_special(struct audit_context *context, int *call_panic)
1190{
1191        struct audit_buffer *ab;
1192        int i;
1193
1194        ab = audit_log_start(context, GFP_KERNEL, context->type);
1195        if (!ab)
1196                return;
1197
1198        switch (context->type) {
1199        case AUDIT_SOCKETCALL: {
1200                int nargs = context->socketcall.nargs;
1201                audit_log_format(ab, "nargs=%d", nargs);
1202                for (i = 0; i < nargs; i++)
1203                        audit_log_format(ab, " a%d=%lx", i,
1204                                context->socketcall.args[i]);
1205                break; }
1206        case AUDIT_IPC: {
1207                u32 osid = context->ipc.osid;
1208
1209                audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1210                                 from_kuid(&init_user_ns, context->ipc.uid),
1211                                 from_kgid(&init_user_ns, context->ipc.gid),
1212                                 context->ipc.mode);
1213                if (osid) {
1214                        char *ctx = NULL;
1215                        u32 len;
1216                        if (security_secid_to_secctx(osid, &ctx, &len)) {
1217                                audit_log_format(ab, " osid=%u", osid);
1218                                *call_panic = 1;
1219                        } else {
1220                                audit_log_format(ab, " obj=%s", ctx);
1221                                security_release_secctx(ctx, len);
1222                        }
1223                }
1224                if (context->ipc.has_perm) {
1225                        audit_log_end(ab);
1226                        ab = audit_log_start(context, GFP_KERNEL,
1227                                             AUDIT_IPC_SET_PERM);
1228                        if (unlikely(!ab))
1229                                return;
1230                        audit_log_format(ab,
1231                                "qbytes=%lx ouid=%u ogid=%u mode=%#ho",
1232                                context->ipc.qbytes,
1233                                context->ipc.perm_uid,
1234                                context->ipc.perm_gid,
1235                                context->ipc.perm_mode);
1236                }
1237                break; }
1238        case AUDIT_MQ_OPEN: {
1239                audit_log_format(ab,
1240                        "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
1241                        "mq_msgsize=%ld mq_curmsgs=%ld",
1242                        context->mq_open.oflag, context->mq_open.mode,
1243                        context->mq_open.attr.mq_flags,
1244                        context->mq_open.attr.mq_maxmsg,
1245                        context->mq_open.attr.mq_msgsize,
1246                        context->mq_open.attr.mq_curmsgs);
1247                break; }
1248        case AUDIT_MQ_SENDRECV: {
1249                audit_log_format(ab,
1250                        "mqdes=%d msg_len=%zd msg_prio=%u "
1251                        "abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1252                        context->mq_sendrecv.mqdes,
1253                        context->mq_sendrecv.msg_len,
1254                        context->mq_sendrecv.msg_prio,
1255                        context->mq_sendrecv.abs_timeout.tv_sec,
1256                        context->mq_sendrecv.abs_timeout.tv_nsec);
1257                break; }
1258        case AUDIT_MQ_NOTIFY: {
1259                audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1260                                context->mq_notify.mqdes,
1261                                context->mq_notify.sigev_signo);
1262                break; }
1263        case AUDIT_MQ_GETSETATTR: {
1264                struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1265                audit_log_format(ab,
1266                        "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1267                        "mq_curmsgs=%ld ",
1268                        context->mq_getsetattr.mqdes,
1269                        attr->mq_flags, attr->mq_maxmsg,
1270                        attr->mq_msgsize, attr->mq_curmsgs);
1271                break; }
1272        case AUDIT_CAPSET: {
1273                audit_log_format(ab, "pid=%d", context->capset.pid);
1274                audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1275                audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1276                audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1277                break; }
1278        case AUDIT_MMAP: {
1279                audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
1280                                 context->mmap.flags);
1281                break; }
1282        }
1283        audit_log_end(ab);
1284}
1285
1286static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1287{
1288        int i, call_panic = 0;
1289        struct audit_buffer *ab;
1290        struct audit_aux_data *aux;
1291        struct audit_names *n;
1292
1293        /* tsk == current */
1294        context->personality = tsk->personality;
1295
1296        ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1297        if (!ab)
1298                return;         /* audit_panic has been called */
1299        audit_log_format(ab, "arch=%x syscall=%d",
1300                         context->arch, context->major);
1301        if (context->personality != PER_LINUX)
1302                audit_log_format(ab, " per=%lx", context->personality);
1303        if (context->return_valid)
1304                audit_log_format(ab, " success=%s exit=%ld",
1305                                 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1306                                 context->return_code);
1307
1308        audit_log_format(ab,
1309                         " a0=%lx a1=%lx a2=%lx a3=%lx items=%d",
1310                         context->argv[0],
1311                         context->argv[1],
1312                         context->argv[2],
1313                         context->argv[3],
1314                         context->name_count);
1315
1316        audit_log_task_info(ab, tsk);
1317        audit_log_key(ab, context->filterkey);
1318        audit_log_end(ab);
1319
1320        for (aux = context->aux; aux; aux = aux->next) {
1321
1322                ab = audit_log_start(context, GFP_KERNEL, aux->type);
1323                if (!ab)
1324                        continue; /* audit_panic has been called */
1325
1326                switch (aux->type) {
1327
1328                case AUDIT_EXECVE: {
1329                        struct audit_aux_data_execve *axi = (void *)aux;
1330                        audit_log_execve_info(context, &ab, axi);
1331                        break; }
1332
1333                case AUDIT_BPRM_FCAPS: {
1334                        struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1335                        audit_log_format(ab, "fver=%x", axs->fcap_ver);
1336                        audit_log_cap(ab, "fp", &axs->fcap.permitted);
1337                        audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1338                        audit_log_format(ab, " fe=%d", axs->fcap.fE);
1339                        audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1340                        audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1341                        audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1342                        audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
1343                        audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
1344                        audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
1345                        break; }
1346
1347                }
1348                audit_log_end(ab);
1349        }
1350
1351        if (context->type)
1352                show_special(context, &call_panic);
1353
1354        if (context->fds[0] >= 0) {
1355                ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1356                if (ab) {
1357                        audit_log_format(ab, "fd0=%d fd1=%d",
1358                                        context->fds[0], context->fds[1]);
1359                        audit_log_end(ab);
1360                }
1361        }
1362
1363        if (context->sockaddr_len) {
1364                ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1365                if (ab) {
1366                        audit_log_format(ab, "saddr=");
1367                        audit_log_n_hex(ab, (void *)context->sockaddr,
1368                                        context->sockaddr_len);
1369                        audit_log_end(ab);
1370                }
1371        }
1372
1373        for (aux = context->aux_pids; aux; aux = aux->next) {
1374                struct audit_aux_data_pids *axs = (void *)aux;
1375
1376                for (i = 0; i < axs->pid_count; i++)
1377                        if (audit_log_pid_context(context, axs->target_pid[i],
1378                                                  axs->target_auid[i],
1379                                                  axs->target_uid[i],
1380                                                  axs->target_sessionid[i],
1381                                                  axs->target_sid[i],
1382                                                  axs->target_comm[i]))
1383                                call_panic = 1;
1384        }
1385
1386        if (context->target_pid &&
1387            audit_log_pid_context(context, context->target_pid,
1388                                  context->target_auid, context->target_uid,
1389                                  context->target_sessionid,
1390                                  context->target_sid, context->target_comm))
1391                        call_panic = 1;
1392
1393        if (context->pwd.dentry && context->pwd.mnt) {
1394                ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1395                if (ab) {
1396                        audit_log_d_path(ab, " cwd=", &context->pwd);
1397                        audit_log_end(ab);
1398                }
1399        }
1400
1401        i = 0;
1402        list_for_each_entry(n, &context->names_list, list)
1403                audit_log_name(context, n, NULL, i++, &call_panic);
1404
1405        /* Send end of event record to help user space know we are finished */
1406        ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1407        if (ab)
1408                audit_log_end(ab);
1409        if (call_panic)
1410                audit_panic("error converting sid to string");
1411}
1412
1413/**
1414 * audit_free - free a per-task audit context
1415 * @tsk: task whose audit context block to free
1416 *
1417 * Called from copy_process and do_exit
1418 */
1419void __audit_free(struct task_struct *tsk)
1420{
1421        struct audit_context *context;
1422
1423        context = audit_get_context(tsk, 0, 0);
1424        if (!context)
1425                return;
1426
1427        /* Check for system calls that do not go through the exit
1428         * function (e.g., exit_group), then free context block.
1429         * We use GFP_ATOMIC here because we might be doing this
1430         * in the context of the idle thread */
1431        /* that can happen only if we are called from do_exit() */
1432        if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1433                audit_log_exit(context, tsk);
1434        if (!list_empty(&context->killed_trees))
1435                audit_kill_trees(&context->killed_trees);
1436
1437        audit_free_context(context);
1438}
1439
1440/**
1441 * audit_syscall_entry - fill in an audit record at syscall entry
1442 * @arch: architecture type
1443 * @major: major syscall type (function)
1444 * @a1: additional syscall register 1
1445 * @a2: additional syscall register 2
1446 * @a3: additional syscall register 3
1447 * @a4: additional syscall register 4
1448 *
1449 * Fill in audit context at syscall entry.  This only happens if the
1450 * audit context was created when the task was created and the state or
1451 * filters demand the audit context be built.  If the state from the
1452 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1453 * then the record will be written at syscall exit time (otherwise, it
1454 * will only be written if another part of the kernel requests that it
1455 * be written).
1456 */
1457void __audit_syscall_entry(int arch, int major,
1458                         unsigned long a1, unsigned long a2,
1459                         unsigned long a3, unsigned long a4)
1460{
1461        struct task_struct *tsk = current;
1462        struct audit_context *context = tsk->audit_context;
1463        enum audit_state     state;
1464
1465        if (!context)
1466                return;
1467
1468        BUG_ON(context->in_syscall || context->name_count);
1469
1470        if (!audit_enabled)
1471                return;
1472
1473        context->arch       = arch;
1474        context->major      = major;
1475        context->argv[0]    = a1;
1476        context->argv[1]    = a2;
1477        context->argv[2]    = a3;
1478        context->argv[3]    = a4;
1479
1480        state = context->state;
1481        context->dummy = !audit_n_rules;
1482        if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
1483                context->prio = 0;
1484                state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1485        }
1486        if (state == AUDIT_DISABLED)
1487                return;
1488
1489        context->serial     = 0;
1490        context->ctime      = CURRENT_TIME;
1491        context->in_syscall = 1;
1492        context->current_state  = state;
1493        context->ppid       = 0;
1494}
1495
1496/**
1497 * audit_syscall_exit - deallocate audit context after a system call
1498 * @success: success value of the syscall
1499 * @return_code: return value of the syscall
1500 *
1501 * Tear down after system call.  If the audit context has been marked as
1502 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1503 * filtering, or because some other part of the kernel wrote an audit
1504 * message), then write out the syscall information.  In call cases,
1505 * free the names stored from getname().
1506 */
1507void __audit_syscall_exit(int success, long return_code)
1508{
1509        struct task_struct *tsk = current;
1510        struct audit_context *context;
1511
1512        if (success)
1513                success = AUDITSC_SUCCESS;
1514        else
1515                success = AUDITSC_FAILURE;
1516
1517        context = audit_get_context(tsk, success, return_code);
1518        if (!context)
1519                return;
1520
1521        if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1522                audit_log_exit(context, tsk);
1523
1524        context->in_syscall = 0;
1525        context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1526
1527        if (!list_empty(&context->killed_trees))
1528                audit_kill_trees(&context->killed_trees);
1529
1530        audit_free_names(context);
1531        unroll_tree_refs(context, NULL, 0);
1532        audit_free_aux(context);
1533        context->aux = NULL;
1534        context->aux_pids = NULL;
1535        context->target_pid = 0;
1536        context->target_sid = 0;
1537        context->sockaddr_len = 0;
1538        context->type = 0;
1539        context->fds[0] = -1;
1540        if (context->state != AUDIT_RECORD_CONTEXT) {
1541                kfree(context->filterkey);
1542                context->filterkey = NULL;
1543        }
1544        tsk->audit_context = context;
1545}
1546
1547static inline void handle_one(const struct inode *inode)
1548{
1549#ifdef CONFIG_AUDIT_TREE
1550        struct audit_context *context;
1551        struct audit_tree_refs *p;
1552        struct audit_chunk *chunk;
1553        int count;
1554        if (likely(hlist_empty(&inode->i_fsnotify_marks)))
1555                return;
1556        context = current->audit_context;
1557        p = context->trees;
1558        count = context->tree_count;
1559        rcu_read_lock();
1560        chunk = audit_tree_lookup(inode);
1561        rcu_read_unlock();
1562        if (!chunk)
1563                return;
1564        if (likely(put_tree_ref(context, chunk)))
1565                return;
1566        if (unlikely(!grow_tree_refs(context))) {
1567                printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
1568                audit_set_auditable(context);
1569                audit_put_chunk(chunk);
1570                unroll_tree_refs(context, p, count);
1571                return;
1572        }
1573        put_tree_ref(context, chunk);
1574#endif
1575}
1576
1577static void handle_path(const struct dentry *dentry)
1578{
1579#ifdef CONFIG_AUDIT_TREE
1580        struct audit_context *context;
1581        struct audit_tree_refs *p;
1582        const struct dentry *d, *parent;
1583        struct audit_chunk *drop;
1584        unsigned long seq;
1585        int count;
1586
1587        context = current->audit_context;
1588        p = context->trees;
1589        count = context->tree_count;
1590retry:
1591        drop = NULL;
1592        d = dentry;
1593        rcu_read_lock();
1594        seq = read_seqbegin(&rename_lock);
1595        for(;;) {
1596                struct inode *inode = d->d_inode;
1597                if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
1598                        struct audit_chunk *chunk;
1599                        chunk = audit_tree_lookup(inode);
1600                        if (chunk) {
1601                                if (unlikely(!put_tree_ref(context, chunk))) {
1602                                        drop = chunk;
1603                                        break;
1604                                }
1605                        }
1606                }
1607                parent = d->d_parent;
1608                if (parent == d)
1609                        break;
1610                d = parent;
1611        }
1612        if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
1613                rcu_read_unlock();
1614                if (!drop) {
1615                        /* just a race with rename */
1616                        unroll_tree_refs(context, p, count);
1617                        goto retry;
1618                }
1619                audit_put_chunk(drop);
1620                if (grow_tree_refs(context)) {
1621                        /* OK, got more space */
1622                        unroll_tree_refs(context, p, count);
1623                        goto retry;
1624                }
1625                /* too bad */
1626                printk(KERN_WARNING
1627                        "out of memory, audit has lost a tree reference\n");
1628                unroll_tree_refs(context, p, count);
1629                audit_set_auditable(context);
1630                return;
1631        }
1632        rcu_read_unlock();
1633#endif
1634}
1635
1636static struct audit_names *audit_alloc_name(struct audit_context *context,
1637                                                unsigned char type)
1638{
1639        struct audit_names *aname;
1640
1641        if (context->name_count < AUDIT_NAMES) {
1642                aname = &context->preallocated_names[context->name_count];
1643                memset(aname, 0, sizeof(*aname));
1644        } else {
1645                aname = kzalloc(sizeof(*aname), GFP_NOFS);
1646                if (!aname)
1647                        return NULL;
1648                aname->should_free = true;
1649        }
1650
1651        aname->ino = (unsigned long)-1;
1652        aname->type = type;
1653        list_add_tail(&aname->list, &context->names_list);
1654
1655        context->name_count++;
1656#if AUDIT_DEBUG
1657        context->ino_count++;
1658#endif
1659        return aname;
1660}
1661
1662/**
1663 * audit_reusename - fill out filename with info from existing entry
1664 * @uptr: userland ptr to pathname
1665 *
1666 * Search the audit_names list for the current audit context. If there is an
1667 * existing entry with a matching "uptr" then return the filename
1668 * associated with that audit_name. If not, return NULL.
1669 */
1670struct filename *
1671__audit_reusename(const __user char *uptr)
1672{
1673        struct audit_context *context = current->audit_context;
1674        struct audit_names *n;
1675
1676        list_for_each_entry(n, &context->names_list, list) {
1677                if (!n->name)
1678                        continue;
1679                if (n->name->uptr == uptr)
1680                        return n->name;
1681        }
1682        return NULL;
1683}
1684
1685/**
1686 * audit_getname - add a name to the list
1687 * @name: name to add
1688 *
1689 * Add a name to the list of audit names for this context.
1690 * Called from fs/namei.c:getname().
1691 */
1692void __audit_getname(struct filename *name)
1693{
1694        struct audit_context *context = current->audit_context;
1695        struct audit_names *n;
1696
1697        if (!context->in_syscall) {
1698#if AUDIT_DEBUG == 2
1699                printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1700                       __FILE__, __LINE__, context->serial, name);
1701                dump_stack();
1702#endif
1703                return;
1704        }
1705
1706#if AUDIT_DEBUG
1707        /* The filename _must_ have a populated ->name */
1708        BUG_ON(!name->name);
1709#endif
1710
1711        n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
1712        if (!n)
1713                return;
1714
1715        n->name = name;
1716        n->name_len = AUDIT_NAME_FULL;
1717        n->name_put = true;
1718        name->aname = n;
1719
1720        if (!context->pwd.dentry)
1721                get_fs_pwd(current->fs, &context->pwd);
1722}
1723
1724/* audit_putname - intercept a putname request
1725 * @name: name to intercept and delay for putname
1726 *
1727 * If we have stored the name from getname in the audit context,
1728 * then we delay the putname until syscall exit.
1729 * Called from include/linux/fs.h:putname().
1730 */
1731void audit_putname(struct filename *name)
1732{
1733        struct audit_context *context = current->audit_context;
1734
1735        BUG_ON(!context);
1736        if (!context->in_syscall) {
1737#if AUDIT_DEBUG == 2
1738                printk(KERN_ERR "%s:%d(:%d): final_putname(%p)\n",
1739                       __FILE__, __LINE__, context->serial, name);
1740                if (context->name_count) {
1741                        struct audit_names *n;
1742                        int i = 0;
1743
1744                        list_for_each_entry(n, &context->names_list, list)
1745                                printk(KERN_ERR "name[%d] = %p = %s\n", i++,
1746                                       n->name, n->name->name ?: "(null)");
1747                        }
1748#endif
1749                final_putname(name);
1750        }
1751#if AUDIT_DEBUG
1752        else {
1753                ++context->put_count;
1754                if (context->put_count > context->name_count) {
1755                        printk(KERN_ERR "%s:%d(:%d): major=%d"
1756                               " in_syscall=%d putname(%p) name_count=%d"
1757                               " put_count=%d\n",
1758                               __FILE__, __LINE__,
1759                               context->serial, context->major,
1760                               context->in_syscall, name->name,
1761                               context->name_count, context->put_count);
1762                        dump_stack();
1763                }
1764        }
1765#endif
1766}
1767
1768/**
1769 * __audit_inode - store the inode and device from a lookup
1770 * @name: name being audited
1771 * @dentry: dentry being audited
1772 * @parent: does this dentry represent the parent?
1773 */
1774void __audit_inode(struct filename *name, const struct dentry *dentry,
1775                   unsigned int parent)
1776{
1777        struct audit_context *context = current->audit_context;
1778        const struct inode *inode = dentry->d_inode;
1779        struct audit_names *n;
1780
1781        if (!context->in_syscall)
1782                return;
1783
1784        if (!name)
1785                goto out_alloc;
1786
1787#if AUDIT_DEBUG
1788        /* The struct filename _must_ have a populated ->name */
1789        BUG_ON(!name->name);
1790#endif
1791        /*
1792         * If we have a pointer to an audit_names entry already, then we can
1793         * just use it directly if the type is correct.
1794         */
1795        n = name->aname;
1796        if (n) {
1797                if (parent) {
1798                        if (n->type == AUDIT_TYPE_PARENT ||
1799                            n->type == AUDIT_TYPE_UNKNOWN)
1800                                goto out;
1801                } else {
1802                        if (n->type != AUDIT_TYPE_PARENT)
1803                                goto out;
1804                }
1805        }
1806
1807        list_for_each_entry_reverse(n, &context->names_list, list) {
1808                /* does the name pointer match? */
1809                if (!n->name || n->name->name != name->name)
1810                        continue;
1811
1812                /* match the correct record type */
1813                if (parent) {
1814                        if (n->type == AUDIT_TYPE_PARENT ||
1815                            n->type == AUDIT_TYPE_UNKNOWN)
1816                                goto out;
1817                } else {
1818                        if (n->type != AUDIT_TYPE_PARENT)
1819                                goto out;
1820                }
1821        }
1822
1823out_alloc:
1824        /* unable to find the name from a previous getname(). Allocate a new
1825         * anonymous entry.
1826         */
1827        n = audit_alloc_name(context, AUDIT_TYPE_NORMAL);
1828        if (!n)
1829                return;
1830out:
1831        if (parent) {
1832                n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
1833                n->type = AUDIT_TYPE_PARENT;
1834        } else {
1835                n->name_len = AUDIT_NAME_FULL;
1836                n->type = AUDIT_TYPE_NORMAL;
1837        }
1838        handle_path(dentry);
1839        audit_copy_inode(n, dentry, inode);
1840}
1841
1842/**
1843 * __audit_inode_child - collect inode info for created/removed objects
1844 * @parent: inode of dentry parent
1845 * @dentry: dentry being audited
1846 * @type:   AUDIT_TYPE_* value that we're looking for
1847 *
1848 * For syscalls that create or remove filesystem objects, audit_inode
1849 * can only collect information for the filesystem object's parent.
1850 * This call updates the audit context with the child's information.
1851 * Syscalls that create a new filesystem object must be hooked after
1852 * the object is created.  Syscalls that remove a filesystem object
1853 * must be hooked prior, in order to capture the target inode during
1854 * unsuccessful attempts.
1855 */
1856void __audit_inode_child(const struct inode *parent,
1857                         const struct dentry *dentry,
1858                         const unsigned char type)
1859{
1860        struct audit_context *context = current->audit_context;
1861        const struct inode *inode = dentry->d_inode;
1862        const char *dname = dentry->d_name.name;
1863        struct audit_names *n, *found_parent = NULL, *found_child = NULL;
1864
1865        if (!context->in_syscall)
1866                return;
1867
1868        if (inode)
1869                handle_one(inode);
1870
1871        /* look for a parent entry first */
1872        list_for_each_entry(n, &context->names_list, list) {
1873                if (!n->name || n->type != AUDIT_TYPE_PARENT)
1874                        continue;
1875
1876                if (n->ino == parent->i_ino &&
1877                    !audit_compare_dname_path(dname, n->name->name, n->name_len)) {
1878                        found_parent = n;
1879                        break;
1880                }
1881        }
1882
1883        /* is there a matching child entry? */
1884        list_for_each_entry(n, &context->names_list, list) {
1885                /* can only match entries that have a name */
1886                if (!n->name || n->type != type)
1887                        continue;
1888
1889                /* if we found a parent, make sure this one is a child of it */
1890                if (found_parent && (n->name != found_parent->name))
1891                        continue;
1892
1893                if (!strcmp(dname, n->name->name) ||
1894                    !audit_compare_dname_path(dname, n->name->name,
1895                                                found_parent ?
1896                                                found_parent->name_len :
1897                                                AUDIT_NAME_FULL)) {
1898                        found_child = n;
1899                        break;
1900                }
1901        }
1902
1903        if (!found_parent) {
1904                /* create a new, "anonymous" parent record */
1905                n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
1906                if (!n)
1907                        return;
1908                audit_copy_inode(n, NULL, parent);
1909        }
1910
1911        if (!found_child) {
1912                found_child = audit_alloc_name(context, type);
1913                if (!found_child)
1914                        return;
1915
1916                /* Re-use the name belonging to the slot for a matching parent
1917                 * directory. All names for this context are relinquished in
1918                 * audit_free_names() */
1919                if (found_parent) {
1920                        found_child->name = found_parent->name;
1921                        found_child->name_len = AUDIT_NAME_FULL;
1922                        /* don't call __putname() */
1923                        found_child->name_put = false;
1924                }
1925        }
1926        if (inode)
1927                audit_copy_inode(found_child, dentry, inode);
1928        else
1929                found_child->ino = (unsigned long)-1;
1930}
1931EXPORT_SYMBOL_GPL(__audit_inode_child);
1932
1933/**
1934 * auditsc_get_stamp - get local copies of audit_context values
1935 * @ctx: audit_context for the task
1936 * @t: timespec to store time recorded in the audit_context
1937 * @serial: serial value that is recorded in the audit_context
1938 *
1939 * Also sets the context as auditable.
1940 */
1941int auditsc_get_stamp(struct audit_context *ctx,
1942                       struct timespec *t, unsigned int *serial)
1943{
1944        if (!ctx->in_syscall)
1945                return 0;
1946        if (!ctx->serial)
1947                ctx->serial = audit_serial();
1948        t->tv_sec  = ctx->ctime.tv_sec;
1949        t->tv_nsec = ctx->ctime.tv_nsec;
1950        *serial    = ctx->serial;
1951        if (!ctx->prio) {
1952                ctx->prio = 1;
1953                ctx->current_state = AUDIT_RECORD_CONTEXT;
1954        }
1955        return 1;
1956}
1957
1958/* global counter which is incremented every time something logs in */
1959static atomic_t session_id = ATOMIC_INIT(0);
1960
1961/**
1962 * audit_set_loginuid - set current task's audit_context loginuid
1963 * @loginuid: loginuid value
1964 *
1965 * Returns 0.
1966 *
1967 * Called (set) from fs/proc/base.c::proc_loginuid_write().
1968 */
1969int audit_set_loginuid(kuid_t loginuid)
1970{
1971        struct task_struct *task = current;
1972        struct audit_context *context = task->audit_context;
1973        unsigned int sessionid;
1974
1975#ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE
1976        if (audit_loginuid_set(task))
1977                return -EPERM;
1978#else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
1979        if (!capable(CAP_AUDIT_CONTROL))
1980                return -EPERM;
1981#endif  /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
1982
1983        sessionid = atomic_inc_return(&session_id);
1984        if (context && context->in_syscall) {
1985                struct audit_buffer *ab;
1986
1987                ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
1988                if (ab) {
1989                        audit_log_format(ab, "login pid=%d uid=%u "
1990                                "old auid=%u new auid=%u"
1991                                " old ses=%u new ses=%u",
1992                                task->pid,
1993                                from_kuid(&init_user_ns, task_uid(task)),
1994                                from_kuid(&init_user_ns, task->loginuid),
1995                                from_kuid(&init_user_ns, loginuid),
1996                                task->sessionid, sessionid);
1997                        audit_log_end(ab);
1998                }
1999        }
2000        task->sessionid = sessionid;
2001        task->loginuid = loginuid;
2002        return 0;
2003}
2004
2005/**
2006 * __audit_mq_open - record audit data for a POSIX MQ open
2007 * @oflag: open flag
2008 * @mode: mode bits
2009 * @attr: queue attributes
2010 *
2011 */
2012void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2013{
2014        struct audit_context *context = current->audit_context;
2015
2016        if (attr)
2017                memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2018        else
2019                memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2020
2021        context->mq_open.oflag = oflag;
2022        context->mq_open.mode = mode;
2023
2024        context->type = AUDIT_MQ_OPEN;
2025}
2026
2027/**
2028 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2029 * @mqdes: MQ descriptor
2030 * @msg_len: Message length
2031 * @msg_prio: Message priority
2032 * @abs_timeout: Message timeout in absolute time
2033 *
2034 */
2035void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2036                        const struct timespec *abs_timeout)
2037{
2038        struct audit_context *context = current->audit_context;
2039        struct timespec *p = &context->mq_sendrecv.abs_timeout;
2040
2041        if (abs_timeout)
2042                memcpy(p, abs_timeout, sizeof(struct timespec));
2043        else
2044                memset(p, 0, sizeof(struct timespec));
2045
2046        context->mq_sendrecv.mqdes = mqdes;
2047        context->mq_sendrecv.msg_len = msg_len;
2048        context->mq_sendrecv.msg_prio = msg_prio;
2049
2050        context->type = AUDIT_MQ_SENDRECV;
2051}
2052
2053/**
2054 * __audit_mq_notify - record audit data for a POSIX MQ notify
2055 * @mqdes: MQ descriptor
2056 * @notification: Notification event
2057 *
2058 */
2059
2060void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2061{
2062        struct audit_context *context = current->audit_context;
2063
2064        if (notification)
2065                context->mq_notify.sigev_signo = notification->sigev_signo;
2066        else
2067                context->mq_notify.sigev_signo = 0;
2068
2069        context->mq_notify.mqdes = mqdes;
2070        context->type = AUDIT_MQ_NOTIFY;
2071}
2072
2073/**
2074 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2075 * @mqdes: MQ descriptor
2076 * @mqstat: MQ flags
2077 *
2078 */
2079void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2080{
2081        struct audit_context *context = current->audit_context;
2082        context->mq_getsetattr.mqdes = mqdes;
2083        context->mq_getsetattr.mqstat = *mqstat;
2084        context->type = AUDIT_MQ_GETSETATTR;
2085}
2086
2087/**
2088 * audit_ipc_obj - record audit data for ipc object
2089 * @ipcp: ipc permissions
2090 *
2091 */
2092void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2093{
2094        struct audit_context *context = current->audit_context;
2095        context->ipc.uid = ipcp->uid;
2096        context->ipc.gid = ipcp->gid;
2097        context->ipc.mode = ipcp->mode;
2098        context->ipc.has_perm = 0;
2099        security_ipc_getsecid(ipcp, &context->ipc.osid);
2100        context->type = AUDIT_IPC;
2101}
2102
2103/**
2104 * audit_ipc_set_perm - record audit data for new ipc permissions
2105 * @qbytes: msgq bytes
2106 * @uid: msgq user id
2107 * @gid: msgq group id
2108 * @mode: msgq mode (permissions)
2109 *
2110 * Called only after audit_ipc_obj().
2111 */
2112void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
2113{
2114        struct audit_context *context = current->audit_context;
2115
2116        context->ipc.qbytes = qbytes;
2117        context->ipc.perm_uid = uid;
2118        context->ipc.perm_gid = gid;
2119        context->ipc.perm_mode = mode;
2120        context->ipc.has_perm = 1;
2121}
2122
2123int __audit_bprm(struct linux_binprm *bprm)
2124{
2125        struct audit_aux_data_execve *ax;
2126        struct audit_context *context = current->audit_context;
2127
2128        ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2129        if (!ax)
2130                return -ENOMEM;
2131
2132        ax->argc = bprm->argc;
2133        ax->envc = bprm->envc;
2134        ax->mm = bprm->mm;
2135        ax->d.type = AUDIT_EXECVE;
2136        ax->d.next = context->aux;
2137        context->aux = (void *)ax;
2138        return 0;
2139}
2140
2141
2142/**
2143 * audit_socketcall - record audit data for sys_socketcall
2144 * @nargs: number of args, which should not be more than AUDITSC_ARGS.
2145 * @args: args array
2146 *
2147 */
2148int __audit_socketcall(int nargs, unsigned long *args)
2149{
2150        struct audit_context *context = current->audit_context;
2151
2152        if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
2153                return -EINVAL;
2154        context->type = AUDIT_SOCKETCALL;
2155        context->socketcall.nargs = nargs;
2156        memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2157        return 0;
2158}
2159
2160/**
2161 * __audit_fd_pair - record audit data for pipe and socketpair
2162 * @fd1: the first file descriptor
2163 * @fd2: the second file descriptor
2164 *
2165 */
2166void __audit_fd_pair(int fd1, int fd2)
2167{
2168        struct audit_context *context = current->audit_context;
2169        context->fds[0] = fd1;
2170        context->fds[1] = fd2;
2171}
2172
2173/**
2174 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2175 * @len: data length in user space
2176 * @a: data address in kernel space
2177 *
2178 * Returns 0 for success or NULL context or < 0 on error.
2179 */
2180int __audit_sockaddr(int len, void *a)
2181{
2182        struct audit_context *context = current->audit_context;
2183
2184        if (!context->sockaddr) {
2185                void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2186                if (!p)
2187                        return -ENOMEM;
2188                context->sockaddr = p;
2189        }
2190
2191        context->sockaddr_len = len;
2192        memcpy(context->sockaddr, a, len);
2193        return 0;
2194}
2195
2196void __audit_ptrace(struct task_struct *t)
2197{
2198        struct audit_context *context = current->audit_context;
2199
2200        context->target_pid = t->pid;
2201        context->target_auid = audit_get_loginuid(t);
2202        context->target_uid = task_uid(t);
2203        context->target_sessionid = audit_get_sessionid(t);
2204        security_task_getsecid(t, &context->target_sid);
2205        memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2206}
2207
2208/**
2209 * audit_signal_info - record signal info for shutting down audit subsystem
2210 * @sig: signal value
2211 * @t: task being signaled
2212 *
2213 * If the audit subsystem is being terminated, record the task (pid)
2214 * and uid that is doing that.
2215 */
2216int __audit_signal_info(int sig, struct task_struct *t)
2217{
2218        struct audit_aux_data_pids *axp;
2219        struct task_struct *tsk = current;
2220        struct audit_context *ctx = tsk->audit_context;
2221        kuid_t uid = current_uid(), t_uid = task_uid(t);
2222
2223        if (audit_pid && t->tgid == audit_pid) {
2224                if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
2225                        audit_sig_pid = tsk->pid;
2226                        if (uid_valid(tsk->loginuid))
2227                                audit_sig_uid = tsk->loginuid;
2228                        else
2229                                audit_sig_uid = uid;
2230                        security_task_getsecid(tsk, &audit_sig_sid);
2231                }
2232                if (!audit_signals || audit_dummy_context())
2233                        return 0;
2234        }
2235
2236        /* optimize the common case by putting first signal recipient directly
2237         * in audit_context */
2238        if (!ctx->target_pid) {
2239                ctx->target_pid = t->tgid;
2240                ctx->target_auid = audit_get_loginuid(t);
2241                ctx->target_uid = t_uid;
2242                ctx->target_sessionid = audit_get_sessionid(t);
2243                security_task_getsecid(t, &ctx->target_sid);
2244                memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2245                return 0;
2246        }
2247
2248        axp = (void *)ctx->aux_pids;
2249        if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2250                axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2251                if (!axp)
2252                        return -ENOMEM;
2253
2254                axp->d.type = AUDIT_OBJ_PID;
2255                axp->d.next = ctx->aux_pids;
2256                ctx->aux_pids = (void *)axp;
2257        }
2258        BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2259
2260        axp->target_pid[axp->pid_count] = t->tgid;
2261        axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2262        axp->target_uid[axp->pid_count] = t_uid;
2263        axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2264        security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2265        memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2266        axp->pid_count++;
2267
2268        return 0;
2269}
2270
2271/**
2272 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2273 * @bprm: pointer to the bprm being processed
2274 * @new: the proposed new credentials
2275 * @old: the old credentials
2276 *
2277 * Simply check if the proc already has the caps given by the file and if not
2278 * store the priv escalation info for later auditing at the end of the syscall
2279 *
2280 * -Eric
2281 */
2282int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2283                           const struct cred *new, const struct cred *old)
2284{
2285        struct audit_aux_data_bprm_fcaps *ax;
2286        struct audit_context *context = current->audit_context;
2287        struct cpu_vfs_cap_data vcaps;
2288        struct dentry *dentry;
2289
2290        ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2291        if (!ax)
2292                return -ENOMEM;
2293
2294        ax->d.type = AUDIT_BPRM_FCAPS;
2295        ax->d.next = context->aux;
2296        context->aux = (void *)ax;
2297
2298        dentry = dget(bprm->file->f_dentry);
2299        get_vfs_caps_from_disk(dentry, &vcaps);
2300        dput(dentry);
2301
2302        ax->fcap.permitted = vcaps.permitted;
2303        ax->fcap.inheritable = vcaps.inheritable;
2304        ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2305        ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2306
2307        ax->old_pcap.permitted   = old->cap_permitted;
2308        ax->old_pcap.inheritable = old->cap_inheritable;
2309        ax->old_pcap.effective   = old->cap_effective;
2310
2311        ax->new_pcap.permitted   = new->cap_permitted;
2312        ax->new_pcap.inheritable = new->cap_inheritable;
2313        ax->new_pcap.effective   = new->cap_effective;
2314        return 0;
2315}
2316
2317/**
2318 * __audit_log_capset - store information about the arguments to the capset syscall
2319 * @pid: target pid of the capset call
2320 * @new: the new credentials
2321 * @old: the old (current) credentials
2322 *
2323 * Record the aguments userspace sent to sys_capset for later printing by the
2324 * audit system if applicable
2325 */
2326void __audit_log_capset(pid_t pid,
2327                       const struct cred *new, const struct cred *old)
2328{
2329        struct audit_context *context = current->audit_context;
2330        context->capset.pid = pid;
2331        context->capset.cap.effective   = new->cap_effective;
2332        context->capset.cap.inheritable = new->cap_effective;
2333        context->capset.cap.permitted   = new->cap_permitted;
2334        context->type = AUDIT_CAPSET;
2335}
2336
2337void __audit_mmap_fd(int fd, int flags)
2338{
2339        struct audit_context *context = current->audit_context;
2340        context->mmap.fd = fd;
2341        context->mmap.flags = flags;
2342        context->type = AUDIT_MMAP;
2343}
2344
2345static void audit_log_task(struct audit_buffer *ab)
2346{
2347        kuid_t auid, uid;
2348        kgid_t gid;
2349        unsigned int sessionid;
2350
2351        auid = audit_get_loginuid(current);
2352        sessionid = audit_get_sessionid(current);
2353        current_uid_gid(&uid, &gid);
2354
2355        audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2356                         from_kuid(&init_user_ns, auid),
2357                         from_kuid(&init_user_ns, uid),
2358                         from_kgid(&init_user_ns, gid),
2359                         sessionid);
2360        audit_log_task_context(ab);
2361        audit_log_format(ab, " pid=%d comm=", current->pid);
2362        audit_log_untrustedstring(ab, current->comm);
2363}
2364
2365static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
2366{
2367        audit_log_task(ab);
2368        audit_log_format(ab, " reason=");
2369        audit_log_string(ab, reason);
2370        audit_log_format(ab, " sig=%ld", signr);
2371}
2372/**
2373 * audit_core_dumps - record information about processes that end abnormally
2374 * @signr: signal value
2375 *
2376 * If a process ends with a core dump, something fishy is going on and we
2377 * should record the event for investigation.
2378 */
2379void audit_core_dumps(long signr)
2380{
2381        struct audit_buffer *ab;
2382
2383        if (!audit_enabled)
2384                return;
2385
2386        if (signr == SIGQUIT)   /* don't care for those */
2387                return;
2388
2389        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2390        if (unlikely(!ab))
2391                return;
2392        audit_log_abend(ab, "memory violation", signr);
2393        audit_log_end(ab);
2394}
2395
2396void __audit_seccomp(unsigned long syscall, long signr, int code)
2397{
2398        struct audit_buffer *ab;
2399
2400        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP);
2401        if (unlikely(!ab))
2402                return;
2403        audit_log_task(ab);
2404        audit_log_format(ab, " sig=%ld", signr);
2405        audit_log_format(ab, " syscall=%ld", syscall);
2406        audit_log_format(ab, " compat=%d", is_compat_task());
2407        audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current));
2408        audit_log_format(ab, " code=0x%x", code);
2409        audit_log_end(ab);
2410}
2411
2412struct list_head *audit_killed_trees(void)
2413{
2414        struct audit_context *ctx = current->audit_context;
2415        if (likely(!ctx || !ctx->in_syscall))
2416                return NULL;
2417        return &ctx->killed_trees;
2418}
2419
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