Root/kernel/auditsc.c

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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
46
47#include <linux/init.h>
48#include <asm/types.h>
49#include <linux/atomic.h>
50#include <linux/fs.h>
51#include <linux/namei.h>
52#include <linux/mm.h>
53#include <linux/export.h>
54#include <linux/slab.h>
55#include <linux/mount.h>
56#include <linux/socket.h>
57#include <linux/mqueue.h>
58#include <linux/audit.h>
59#include <linux/personality.h>
60#include <linux/time.h>
61#include <linux/netlink.h>
62#include <linux/compiler.h>
63#include <asm/unistd.h>
64#include <linux/security.h>
65#include <linux/list.h>
66#include <linux/tty.h>
67#include <linux/binfmts.h>
68#include <linux/highmem.h>
69#include <linux/syscalls.h>
70#include <linux/capability.h>
71#include <linux/fs_struct.h>
72#include <linux/compat.h>
73#include <linux/ctype.h>
74
75#include "audit.h"
76
77/* flags stating the success for a syscall */
78#define AUDITSC_INVALID 0
79#define AUDITSC_SUCCESS 1
80#define AUDITSC_FAILURE 2
81
82/* no execve audit message should be longer than this (userspace limits) */
83#define MAX_EXECVE_AUDIT_LEN 7500
84
85/* max length to print of cmdline/proctitle value during audit */
86#define MAX_PROCTITLE_AUDIT_LEN 128
87
88/* number of audit rules */
89int audit_n_rules;
90
91/* determines whether we collect data for signals sent */
92int audit_signals;
93
94struct audit_aux_data {
95    struct audit_aux_data *next;
96    int type;
97};
98
99#define AUDIT_AUX_IPCPERM 0
100
101/* Number of target pids per aux struct. */
102#define AUDIT_AUX_PIDS 16
103
104struct audit_aux_data_pids {
105    struct audit_aux_data d;
106    pid_t target_pid[AUDIT_AUX_PIDS];
107    kuid_t target_auid[AUDIT_AUX_PIDS];
108    kuid_t target_uid[AUDIT_AUX_PIDS];
109    unsigned int target_sessionid[AUDIT_AUX_PIDS];
110    u32 target_sid[AUDIT_AUX_PIDS];
111    char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
112    int pid_count;
113};
114
115struct audit_aux_data_bprm_fcaps {
116    struct audit_aux_data d;
117    struct audit_cap_data fcap;
118    unsigned int fcap_ver;
119    struct audit_cap_data old_pcap;
120    struct audit_cap_data new_pcap;
121};
122
123struct audit_tree_refs {
124    struct audit_tree_refs *next;
125    struct audit_chunk *c[31];
126};
127
128static inline int open_arg(int flags, int mask)
129{
130    int n = ACC_MODE(flags);
131    if (flags & (O_TRUNC | O_CREAT))
132        n |= AUDIT_PERM_WRITE;
133    return n & mask;
134}
135
136static int audit_match_perm(struct audit_context *ctx, int mask)
137{
138    unsigned n;
139    if (unlikely(!ctx))
140        return 0;
141    n = ctx->major;
142
143    switch (audit_classify_syscall(ctx->arch, n)) {
144    case 0: /* native */
145        if ((mask & AUDIT_PERM_WRITE) &&
146             audit_match_class(AUDIT_CLASS_WRITE, n))
147            return 1;
148        if ((mask & AUDIT_PERM_READ) &&
149             audit_match_class(AUDIT_CLASS_READ, n))
150            return 1;
151        if ((mask & AUDIT_PERM_ATTR) &&
152             audit_match_class(AUDIT_CLASS_CHATTR, n))
153            return 1;
154        return 0;
155    case 1: /* 32bit on biarch */
156        if ((mask & AUDIT_PERM_WRITE) &&
157             audit_match_class(AUDIT_CLASS_WRITE_32, n))
158            return 1;
159        if ((mask & AUDIT_PERM_READ) &&
160             audit_match_class(AUDIT_CLASS_READ_32, n))
161            return 1;
162        if ((mask & AUDIT_PERM_ATTR) &&
163             audit_match_class(AUDIT_CLASS_CHATTR_32, n))
164            return 1;
165        return 0;
166    case 2: /* open */
167        return mask & ACC_MODE(ctx->argv[1]);
168    case 3: /* openat */
169        return mask & ACC_MODE(ctx->argv[2]);
170    case 4: /* socketcall */
171        return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
172    case 5: /* execve */
173        return mask & AUDIT_PERM_EXEC;
174    default:
175        return 0;
176    }
177}
178
179static int audit_match_filetype(struct audit_context *ctx, int val)
180{
181    struct audit_names *n;
182    umode_t mode = (umode_t)val;
183
184    if (unlikely(!ctx))
185        return 0;
186
187    list_for_each_entry(n, &ctx->names_list, list) {
188        if ((n->ino != -1) &&
189            ((n->mode & S_IFMT) == mode))
190            return 1;
191    }
192
193    return 0;
194}
195
196/*
197 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
198 * ->first_trees points to its beginning, ->trees - to the current end of data.
199 * ->tree_count is the number of free entries in array pointed to by ->trees.
200 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
201 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously,
202 * it's going to remain 1-element for almost any setup) until we free context itself.
203 * References in it _are_ dropped - at the same time we free/drop aux stuff.
204 */
205
206#ifdef CONFIG_AUDIT_TREE
207static void audit_set_auditable(struct audit_context *ctx)
208{
209    if (!ctx->prio) {
210        ctx->prio = 1;
211        ctx->current_state = AUDIT_RECORD_CONTEXT;
212    }
213}
214
215static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
216{
217    struct audit_tree_refs *p = ctx->trees;
218    int left = ctx->tree_count;
219    if (likely(left)) {
220        p->c[--left] = chunk;
221        ctx->tree_count = left;
222        return 1;
223    }
224    if (!p)
225        return 0;
226    p = p->next;
227    if (p) {
228        p->c[30] = chunk;
229        ctx->trees = p;
230        ctx->tree_count = 30;
231        return 1;
232    }
233    return 0;
234}
235
236static int grow_tree_refs(struct audit_context *ctx)
237{
238    struct audit_tree_refs *p = ctx->trees;
239    ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
240    if (!ctx->trees) {
241        ctx->trees = p;
242        return 0;
243    }
244    if (p)
245        p->next = ctx->trees;
246    else
247        ctx->first_trees = ctx->trees;
248    ctx->tree_count = 31;
249    return 1;
250}
251#endif
252
253static void unroll_tree_refs(struct audit_context *ctx,
254              struct audit_tree_refs *p, int count)
255{
256#ifdef CONFIG_AUDIT_TREE
257    struct audit_tree_refs *q;
258    int n;
259    if (!p) {
260        /* we started with empty chain */
261        p = ctx->first_trees;
262        count = 31;
263        /* if the very first allocation has failed, nothing to do */
264        if (!p)
265            return;
266    }
267    n = count;
268    for (q = p; q != ctx->trees; q = q->next, n = 31) {
269        while (n--) {
270            audit_put_chunk(q->c[n]);
271            q->c[n] = NULL;
272        }
273    }
274    while (n-- > ctx->tree_count) {
275        audit_put_chunk(q->c[n]);
276        q->c[n] = NULL;
277    }
278    ctx->trees = p;
279    ctx->tree_count = count;
280#endif
281}
282
283static void free_tree_refs(struct audit_context *ctx)
284{
285    struct audit_tree_refs *p, *q;
286    for (p = ctx->first_trees; p; p = q) {
287        q = p->next;
288        kfree(p);
289    }
290}
291
292static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
293{
294#ifdef CONFIG_AUDIT_TREE
295    struct audit_tree_refs *p;
296    int n;
297    if (!tree)
298        return 0;
299    /* full ones */
300    for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
301        for (n = 0; n < 31; n++)
302            if (audit_tree_match(p->c[n], tree))
303                return 1;
304    }
305    /* partial */
306    if (p) {
307        for (n = ctx->tree_count; n < 31; n++)
308            if (audit_tree_match(p->c[n], tree))
309                return 1;
310    }
311#endif
312    return 0;
313}
314
315static int audit_compare_uid(kuid_t uid,
316                 struct audit_names *name,
317                 struct audit_field *f,
318                 struct audit_context *ctx)
319{
320    struct audit_names *n;
321    int rc;
322 
323    if (name) {
324        rc = audit_uid_comparator(uid, f->op, name->uid);
325        if (rc)
326            return rc;
327    }
328 
329    if (ctx) {
330        list_for_each_entry(n, &ctx->names_list, list) {
331            rc = audit_uid_comparator(uid, f->op, n->uid);
332            if (rc)
333                return rc;
334        }
335    }
336    return 0;
337}
338
339static int audit_compare_gid(kgid_t gid,
340                 struct audit_names *name,
341                 struct audit_field *f,
342                 struct audit_context *ctx)
343{
344    struct audit_names *n;
345    int rc;
346 
347    if (name) {
348        rc = audit_gid_comparator(gid, f->op, name->gid);
349        if (rc)
350            return rc;
351    }
352 
353    if (ctx) {
354        list_for_each_entry(n, &ctx->names_list, list) {
355            rc = audit_gid_comparator(gid, f->op, n->gid);
356            if (rc)
357                return rc;
358        }
359    }
360    return 0;
361}
362
363static int audit_field_compare(struct task_struct *tsk,
364                   const struct cred *cred,
365                   struct audit_field *f,
366                   struct audit_context *ctx,
367                   struct audit_names *name)
368{
369    switch (f->val) {
370    /* process to file object comparisons */
371    case AUDIT_COMPARE_UID_TO_OBJ_UID:
372        return audit_compare_uid(cred->uid, name, f, ctx);
373    case AUDIT_COMPARE_GID_TO_OBJ_GID:
374        return audit_compare_gid(cred->gid, name, f, ctx);
375    case AUDIT_COMPARE_EUID_TO_OBJ_UID:
376        return audit_compare_uid(cred->euid, name, f, ctx);
377    case AUDIT_COMPARE_EGID_TO_OBJ_GID:
378        return audit_compare_gid(cred->egid, name, f, ctx);
379    case AUDIT_COMPARE_AUID_TO_OBJ_UID:
380        return audit_compare_uid(tsk->loginuid, name, f, ctx);
381    case AUDIT_COMPARE_SUID_TO_OBJ_UID:
382        return audit_compare_uid(cred->suid, name, f, ctx);
383    case AUDIT_COMPARE_SGID_TO_OBJ_GID:
384        return audit_compare_gid(cred->sgid, name, f, ctx);
385    case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
386        return audit_compare_uid(cred->fsuid, name, f, ctx);
387    case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
388        return audit_compare_gid(cred->fsgid, name, f, ctx);
389    /* uid comparisons */
390    case AUDIT_COMPARE_UID_TO_AUID:
391        return audit_uid_comparator(cred->uid, f->op, tsk->loginuid);
392    case AUDIT_COMPARE_UID_TO_EUID:
393        return audit_uid_comparator(cred->uid, f->op, cred->euid);
394    case AUDIT_COMPARE_UID_TO_SUID:
395        return audit_uid_comparator(cred->uid, f->op, cred->suid);
396    case AUDIT_COMPARE_UID_TO_FSUID:
397        return audit_uid_comparator(cred->uid, f->op, cred->fsuid);
398    /* auid comparisons */
399    case AUDIT_COMPARE_AUID_TO_EUID:
400        return audit_uid_comparator(tsk->loginuid, f->op, cred->euid);
401    case AUDIT_COMPARE_AUID_TO_SUID:
402        return audit_uid_comparator(tsk->loginuid, f->op, cred->suid);
403    case AUDIT_COMPARE_AUID_TO_FSUID:
404        return audit_uid_comparator(tsk->loginuid, f->op, cred->fsuid);
405    /* euid comparisons */
406    case AUDIT_COMPARE_EUID_TO_SUID:
407        return audit_uid_comparator(cred->euid, f->op, cred->suid);
408    case AUDIT_COMPARE_EUID_TO_FSUID:
409        return audit_uid_comparator(cred->euid, f->op, cred->fsuid);
410    /* suid comparisons */
411    case AUDIT_COMPARE_SUID_TO_FSUID:
412        return audit_uid_comparator(cred->suid, f->op, cred->fsuid);
413    /* gid comparisons */
414    case AUDIT_COMPARE_GID_TO_EGID:
415        return audit_gid_comparator(cred->gid, f->op, cred->egid);
416    case AUDIT_COMPARE_GID_TO_SGID:
417        return audit_gid_comparator(cred->gid, f->op, cred->sgid);
418    case AUDIT_COMPARE_GID_TO_FSGID:
419        return audit_gid_comparator(cred->gid, f->op, cred->fsgid);
420    /* egid comparisons */
421    case AUDIT_COMPARE_EGID_TO_SGID:
422        return audit_gid_comparator(cred->egid, f->op, cred->sgid);
423    case AUDIT_COMPARE_EGID_TO_FSGID:
424        return audit_gid_comparator(cred->egid, f->op, cred->fsgid);
425    /* sgid comparison */
426    case AUDIT_COMPARE_SGID_TO_FSGID:
427        return audit_gid_comparator(cred->sgid, f->op, cred->fsgid);
428    default:
429        WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n");
430        return 0;
431    }
432    return 0;
433}
434
435/* Determine if any context name data matches a rule's watch data */
436/* Compare a task_struct with an audit_rule. Return 1 on match, 0
437 * otherwise.
438 *
439 * If task_creation is true, this is an explicit indication that we are
440 * filtering a task rule at task creation time. This and tsk == current are
441 * the only situations where tsk->cred may be accessed without an rcu read lock.
442 */
443static int audit_filter_rules(struct task_struct *tsk,
444                  struct audit_krule *rule,
445                  struct audit_context *ctx,
446                  struct audit_names *name,
447                  enum audit_state *state,
448                  bool task_creation)
449{
450    const struct cred *cred;
451    int i, need_sid = 1;
452    u32 sid;
453
454    cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
455
456    for (i = 0; i < rule->field_count; i++) {
457        struct audit_field *f = &rule->fields[i];
458        struct audit_names *n;
459        int result = 0;
460        pid_t pid;
461
462        switch (f->type) {
463        case AUDIT_PID:
464            pid = task_pid_nr(tsk);
465            result = audit_comparator(pid, f->op, f->val);
466            break;
467        case AUDIT_PPID:
468            if (ctx) {
469                if (!ctx->ppid)
470                    ctx->ppid = task_ppid_nr(tsk);
471                result = audit_comparator(ctx->ppid, f->op, f->val);
472            }
473            break;
474        case AUDIT_UID:
475            result = audit_uid_comparator(cred->uid, f->op, f->uid);
476            break;
477        case AUDIT_EUID:
478            result = audit_uid_comparator(cred->euid, f->op, f->uid);
479            break;
480        case AUDIT_SUID:
481            result = audit_uid_comparator(cred->suid, f->op, f->uid);
482            break;
483        case AUDIT_FSUID:
484            result = audit_uid_comparator(cred->fsuid, f->op, f->uid);
485            break;
486        case AUDIT_GID:
487            result = audit_gid_comparator(cred->gid, f->op, f->gid);
488            if (f->op == Audit_equal) {
489                if (!result)
490                    result = in_group_p(f->gid);
491            } else if (f->op == Audit_not_equal) {
492                if (result)
493                    result = !in_group_p(f->gid);
494            }
495            break;
496        case AUDIT_EGID:
497            result = audit_gid_comparator(cred->egid, f->op, f->gid);
498            if (f->op == Audit_equal) {
499                if (!result)
500                    result = in_egroup_p(f->gid);
501            } else if (f->op == Audit_not_equal) {
502                if (result)
503                    result = !in_egroup_p(f->gid);
504            }
505            break;
506        case AUDIT_SGID:
507            result = audit_gid_comparator(cred->sgid, f->op, f->gid);
508            break;
509        case AUDIT_FSGID:
510            result = audit_gid_comparator(cred->fsgid, f->op, f->gid);
511            break;
512        case AUDIT_PERS:
513            result = audit_comparator(tsk->personality, f->op, f->val);
514            break;
515        case AUDIT_ARCH:
516            if (ctx)
517                result = audit_comparator(ctx->arch, f->op, f->val);
518            break;
519
520        case AUDIT_EXIT:
521            if (ctx && ctx->return_valid)
522                result = audit_comparator(ctx->return_code, f->op, f->val);
523            break;
524        case AUDIT_SUCCESS:
525            if (ctx && ctx->return_valid) {
526                if (f->val)
527                    result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
528                else
529                    result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
530            }
531            break;
532        case AUDIT_DEVMAJOR:
533            if (name) {
534                if (audit_comparator(MAJOR(name->dev), f->op, f->val) ||
535                    audit_comparator(MAJOR(name->rdev), f->op, f->val))
536                    ++result;
537            } else if (ctx) {
538                list_for_each_entry(n, &ctx->names_list, list) {
539                    if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
540                        audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
541                        ++result;
542                        break;
543                    }
544                }
545            }
546            break;
547        case AUDIT_DEVMINOR:
548            if (name) {
549                if (audit_comparator(MINOR(name->dev), f->op, f->val) ||
550                    audit_comparator(MINOR(name->rdev), f->op, f->val))
551                    ++result;
552            } else if (ctx) {
553                list_for_each_entry(n, &ctx->names_list, list) {
554                    if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
555                        audit_comparator(MINOR(n->rdev), f->op, f->val)) {
556                        ++result;
557                        break;
558                    }
559                }
560            }
561            break;
562        case AUDIT_INODE:
563            if (name)
564                result = audit_comparator(name->ino, f->op, f->val);
565            else if (ctx) {
566                list_for_each_entry(n, &ctx->names_list, list) {
567                    if (audit_comparator(n->ino, f->op, f->val)) {
568                        ++result;
569                        break;
570                    }
571                }
572            }
573            break;
574        case AUDIT_OBJ_UID:
575            if (name) {
576                result = audit_uid_comparator(name->uid, f->op, f->uid);
577            } else if (ctx) {
578                list_for_each_entry(n, &ctx->names_list, list) {
579                    if (audit_uid_comparator(n->uid, f->op, f->uid)) {
580                        ++result;
581                        break;
582                    }
583                }
584            }
585            break;
586        case AUDIT_OBJ_GID:
587            if (name) {
588                result = audit_gid_comparator(name->gid, f->op, f->gid);
589            } else if (ctx) {
590                list_for_each_entry(n, &ctx->names_list, list) {
591                    if (audit_gid_comparator(n->gid, f->op, f->gid)) {
592                        ++result;
593                        break;
594                    }
595                }
596            }
597            break;
598        case AUDIT_WATCH:
599            if (name)
600                result = audit_watch_compare(rule->watch, name->ino, name->dev);
601            break;
602        case AUDIT_DIR:
603            if (ctx)
604                result = match_tree_refs(ctx, rule->tree);
605            break;
606        case AUDIT_LOGINUID:
607            result = 0;
608            if (ctx)
609                result = audit_uid_comparator(tsk->loginuid, f->op, f->uid);
610            break;
611        case AUDIT_LOGINUID_SET:
612            result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val);
613            break;
614        case AUDIT_SUBJ_USER:
615        case AUDIT_SUBJ_ROLE:
616        case AUDIT_SUBJ_TYPE:
617        case AUDIT_SUBJ_SEN:
618        case AUDIT_SUBJ_CLR:
619            /* NOTE: this may return negative values indicating
620               a temporary error. We simply treat this as a
621               match for now to avoid losing information that
622               may be wanted. An error message will also be
623               logged upon error */
624            if (f->lsm_rule) {
625                if (need_sid) {
626                    security_task_getsecid(tsk, &sid);
627                    need_sid = 0;
628                }
629                result = security_audit_rule_match(sid, f->type,
630                                                  f->op,
631                                                  f->lsm_rule,
632                                                  ctx);
633            }
634            break;
635        case AUDIT_OBJ_USER:
636        case AUDIT_OBJ_ROLE:
637        case AUDIT_OBJ_TYPE:
638        case AUDIT_OBJ_LEV_LOW:
639        case AUDIT_OBJ_LEV_HIGH:
640            /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
641               also applies here */
642            if (f->lsm_rule) {
643                /* Find files that match */
644                if (name) {
645                    result = security_audit_rule_match(
646                               name->osid, f->type, f->op,
647                               f->lsm_rule, ctx);
648                } else if (ctx) {
649                    list_for_each_entry(n, &ctx->names_list, list) {
650                        if (security_audit_rule_match(n->osid, f->type,
651                                          f->op, f->lsm_rule,
652                                          ctx)) {
653                            ++result;
654                            break;
655                        }
656                    }
657                }
658                /* Find ipc objects that match */
659                if (!ctx || ctx->type != AUDIT_IPC)
660                    break;
661                if (security_audit_rule_match(ctx->ipc.osid,
662                                  f->type, f->op,
663                                  f->lsm_rule, ctx))
664                    ++result;
665            }
666            break;
667        case AUDIT_ARG0:
668        case AUDIT_ARG1:
669        case AUDIT_ARG2:
670        case AUDIT_ARG3:
671            if (ctx)
672                result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
673            break;
674        case AUDIT_FILTERKEY:
675            /* ignore this field for filtering */
676            result = 1;
677            break;
678        case AUDIT_PERM:
679            result = audit_match_perm(ctx, f->val);
680            break;
681        case AUDIT_FILETYPE:
682            result = audit_match_filetype(ctx, f->val);
683            break;
684        case AUDIT_FIELD_COMPARE:
685            result = audit_field_compare(tsk, cred, f, ctx, name);
686            break;
687        }
688        if (!result)
689            return 0;
690    }
691
692    if (ctx) {
693        if (rule->prio <= ctx->prio)
694            return 0;
695        if (rule->filterkey) {
696            kfree(ctx->filterkey);
697            ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
698        }
699        ctx->prio = rule->prio;
700    }
701    switch (rule->action) {
702    case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
703    case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
704    }
705    return 1;
706}
707
708/* At process creation time, we can determine if system-call auditing is
709 * completely disabled for this task. Since we only have the task
710 * structure at this point, we can only check uid and gid.
711 */
712static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
713{
714    struct audit_entry *e;
715    enum audit_state state;
716
717    rcu_read_lock();
718    list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
719        if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
720                       &state, true)) {
721            if (state == AUDIT_RECORD_CONTEXT)
722                *key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
723            rcu_read_unlock();
724            return state;
725        }
726    }
727    rcu_read_unlock();
728    return AUDIT_BUILD_CONTEXT;
729}
730
731/* At syscall entry and exit time, this filter is called if the
732 * audit_state is not low enough that auditing cannot take place, but is
733 * also not high enough that we already know we have to write an audit
734 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
735 */
736static enum audit_state audit_filter_syscall(struct task_struct *tsk,
737                         struct audit_context *ctx,
738                         struct list_head *list)
739{
740    struct audit_entry *e;
741    enum audit_state state;
742
743    if (audit_pid && tsk->tgid == audit_pid)
744        return AUDIT_DISABLED;
745
746    rcu_read_lock();
747    if (!list_empty(list)) {
748        int word = AUDIT_WORD(ctx->major);
749        int bit = AUDIT_BIT(ctx->major);
750
751        list_for_each_entry_rcu(e, list, list) {
752            if ((e->rule.mask[word] & bit) == bit &&
753                audit_filter_rules(tsk, &e->rule, ctx, NULL,
754                           &state, false)) {
755                rcu_read_unlock();
756                ctx->current_state = state;
757                return state;
758            }
759        }
760    }
761    rcu_read_unlock();
762    return AUDIT_BUILD_CONTEXT;
763}
764
765/*
766 * Given an audit_name check the inode hash table to see if they match.
767 * Called holding the rcu read lock to protect the use of audit_inode_hash
768 */
769static int audit_filter_inode_name(struct task_struct *tsk,
770                   struct audit_names *n,
771                   struct audit_context *ctx) {
772    int word, bit;
773    int h = audit_hash_ino((u32)n->ino);
774    struct list_head *list = &audit_inode_hash[h];
775    struct audit_entry *e;
776    enum audit_state state;
777
778    word = AUDIT_WORD(ctx->major);
779    bit = AUDIT_BIT(ctx->major);
780
781    if (list_empty(list))
782        return 0;
783
784    list_for_each_entry_rcu(e, list, list) {
785        if ((e->rule.mask[word] & bit) == bit &&
786            audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
787            ctx->current_state = state;
788            return 1;
789        }
790    }
791
792    return 0;
793}
794
795/* At syscall exit time, this filter is called if any audit_names have been
796 * collected during syscall processing. We only check rules in sublists at hash
797 * buckets applicable to the inode numbers in audit_names.
798 * Regarding audit_state, same rules apply as for audit_filter_syscall().
799 */
800void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
801{
802    struct audit_names *n;
803
804    if (audit_pid && tsk->tgid == audit_pid)
805        return;
806
807    rcu_read_lock();
808
809    list_for_each_entry(n, &ctx->names_list, list) {
810        if (audit_filter_inode_name(tsk, n, ctx))
811            break;
812    }
813    rcu_read_unlock();
814}
815
816/* Transfer the audit context pointer to the caller, clearing it in the tsk's struct */
817static inline struct audit_context *audit_take_context(struct task_struct *tsk,
818                              int return_valid,
819                              long return_code)
820{
821    struct audit_context *context = tsk->audit_context;
822
823    if (!context)
824        return NULL;
825    context->return_valid = return_valid;
826
827    /*
828     * we need to fix up the return code in the audit logs if the actual
829     * return codes are later going to be fixed up by the arch specific
830     * signal handlers
831     *
832     * This is actually a test for:
833     * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
834     * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
835     *
836     * but is faster than a bunch of ||
837     */
838    if (unlikely(return_code <= -ERESTARTSYS) &&
839        (return_code >= -ERESTART_RESTARTBLOCK) &&
840        (return_code != -ENOIOCTLCMD))
841        context->return_code = -EINTR;
842    else
843        context->return_code = return_code;
844
845    if (context->in_syscall && !context->dummy) {
846        audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
847        audit_filter_inodes(tsk, context);
848    }
849
850    tsk->audit_context = NULL;
851    return context;
852}
853
854static inline void audit_proctitle_free(struct audit_context *context)
855{
856    kfree(context->proctitle.value);
857    context->proctitle.value = NULL;
858    context->proctitle.len = 0;
859}
860
861static inline void audit_free_names(struct audit_context *context)
862{
863    struct audit_names *n, *next;
864
865#if AUDIT_DEBUG == 2
866    if (context->put_count + context->ino_count != context->name_count) {
867        int i = 0;
868
869        pr_err("%s:%d(:%d): major=%d in_syscall=%d"
870               " name_count=%d put_count=%d ino_count=%d"
871               " [NOT freeing]\n", __FILE__, __LINE__,
872               context->serial, context->major, context->in_syscall,
873               context->name_count, context->put_count,
874               context->ino_count);
875        list_for_each_entry(n, &context->names_list, list) {
876            pr_err("names[%d] = %p = %s\n", i++, n->name,
877                   n->name->name ?: "(null)");
878        }
879        dump_stack();
880        return;
881    }
882#endif
883#if AUDIT_DEBUG
884    context->put_count = 0;
885    context->ino_count = 0;
886#endif
887
888    list_for_each_entry_safe(n, next, &context->names_list, list) {
889        list_del(&n->list);
890        if (n->name && n->name_put)
891            final_putname(n->name);
892        if (n->should_free)
893            kfree(n);
894    }
895    context->name_count = 0;
896    path_put(&context->pwd);
897    context->pwd.dentry = NULL;
898    context->pwd.mnt = NULL;
899}
900
901static inline void audit_free_aux(struct audit_context *context)
902{
903    struct audit_aux_data *aux;
904
905    while ((aux = context->aux)) {
906        context->aux = aux->next;
907        kfree(aux);
908    }
909    while ((aux = context->aux_pids)) {
910        context->aux_pids = aux->next;
911        kfree(aux);
912    }
913}
914
915static inline struct audit_context *audit_alloc_context(enum audit_state state)
916{
917    struct audit_context *context;
918
919    context = kzalloc(sizeof(*context), GFP_KERNEL);
920    if (!context)
921        return NULL;
922    context->state = state;
923    context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
924    INIT_LIST_HEAD(&context->killed_trees);
925    INIT_LIST_HEAD(&context->names_list);
926    return context;
927}
928
929/**
930 * audit_alloc - allocate an audit context block for a task
931 * @tsk: task
932 *
933 * Filter on the task information and allocate a per-task audit context
934 * if necessary. Doing so turns on system call auditing for the
935 * specified task. This is called from copy_process, so no lock is
936 * needed.
937 */
938int audit_alloc(struct task_struct *tsk)
939{
940    struct audit_context *context;
941    enum audit_state state;
942    char *key = NULL;
943
944    if (likely(!audit_ever_enabled))
945        return 0; /* Return if not auditing. */
946
947    state = audit_filter_task(tsk, &key);
948    if (state == AUDIT_DISABLED) {
949        clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
950        return 0;
951    }
952
953    if (!(context = audit_alloc_context(state))) {
954        kfree(key);
955        audit_log_lost("out of memory in audit_alloc");
956        return -ENOMEM;
957    }
958    context->filterkey = key;
959
960    tsk->audit_context = context;
961    set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
962    return 0;
963}
964
965static inline void audit_free_context(struct audit_context *context)
966{
967    audit_free_names(context);
968    unroll_tree_refs(context, NULL, 0);
969    free_tree_refs(context);
970    audit_free_aux(context);
971    kfree(context->filterkey);
972    kfree(context->sockaddr);
973    audit_proctitle_free(context);
974    kfree(context);
975}
976
977static int audit_log_pid_context(struct audit_context *context, pid_t pid,
978                 kuid_t auid, kuid_t uid, unsigned int sessionid,
979                 u32 sid, char *comm)
980{
981    struct audit_buffer *ab;
982    char *ctx = NULL;
983    u32 len;
984    int rc = 0;
985
986    ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
987    if (!ab)
988        return rc;
989
990    audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
991             from_kuid(&init_user_ns, auid),
992             from_kuid(&init_user_ns, uid), sessionid);
993    if (sid) {
994        if (security_secid_to_secctx(sid, &ctx, &len)) {
995            audit_log_format(ab, " obj=(none)");
996            rc = 1;
997        } else {
998            audit_log_format(ab, " obj=%s", ctx);
999            security_release_secctx(ctx, len);
1000        }
1001    }
1002    audit_log_format(ab, " ocomm=");
1003    audit_log_untrustedstring(ab, comm);
1004    audit_log_end(ab);
1005
1006    return rc;
1007}
1008
1009/*
1010 * to_send and len_sent accounting are very loose estimates. We aren't
1011 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
1012 * within about 500 bytes (next page boundary)
1013 *
1014 * why snprintf? an int is up to 12 digits long. if we just assumed when
1015 * logging that a[%d]= was going to be 16 characters long we would be wasting
1016 * space in every audit message. In one 7500 byte message we can log up to
1017 * about 1000 min size arguments. That comes down to about 50% waste of space
1018 * if we didn't do the snprintf to find out how long arg_num_len was.
1019 */
1020static int audit_log_single_execve_arg(struct audit_context *context,
1021                    struct audit_buffer **ab,
1022                    int arg_num,
1023                    size_t *len_sent,
1024                    const char __user *p,
1025                    char *buf)
1026{
1027    char arg_num_len_buf[12];
1028    const char __user *tmp_p = p;
1029    /* how many digits are in arg_num? 5 is the length of ' a=""' */
1030    size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5;
1031    size_t len, len_left, to_send;
1032    size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1033    unsigned int i, has_cntl = 0, too_long = 0;
1034    int ret;
1035
1036    /* strnlen_user includes the null we don't want to send */
1037    len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1038
1039    /*
1040     * We just created this mm, if we can't find the strings
1041     * we just copied into it something is _very_ wrong. Similar
1042     * for strings that are too long, we should not have created
1043     * any.
1044     */
1045    if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1046        WARN_ON(1);
1047        send_sig(SIGKILL, current, 0);
1048        return -1;
1049    }
1050
1051    /* walk the whole argument looking for non-ascii chars */
1052    do {
1053        if (len_left > MAX_EXECVE_AUDIT_LEN)
1054            to_send = MAX_EXECVE_AUDIT_LEN;
1055        else
1056            to_send = len_left;
1057        ret = copy_from_user(buf, tmp_p, to_send);
1058        /*
1059         * There is no reason for this copy to be short. We just
1060         * copied them here, and the mm hasn't been exposed to user-
1061         * space yet.
1062         */
1063        if (ret) {
1064            WARN_ON(1);
1065            send_sig(SIGKILL, current, 0);
1066            return -1;
1067        }
1068        buf[to_send] = '\0';
1069        has_cntl = audit_string_contains_control(buf, to_send);
1070        if (has_cntl) {
1071            /*
1072             * hex messages get logged as 2 bytes, so we can only
1073             * send half as much in each message
1074             */
1075            max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1076            break;
1077        }
1078        len_left -= to_send;
1079        tmp_p += to_send;
1080    } while (len_left > 0);
1081
1082    len_left = len;
1083
1084    if (len > max_execve_audit_len)
1085        too_long = 1;
1086
1087    /* rewalk the argument actually logging the message */
1088    for (i = 0; len_left > 0; i++) {
1089        int room_left;
1090
1091        if (len_left > max_execve_audit_len)
1092            to_send = max_execve_audit_len;
1093        else
1094            to_send = len_left;
1095
1096        /* do we have space left to send this argument in this ab? */
1097        room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1098        if (has_cntl)
1099            room_left -= (to_send * 2);
1100        else
1101            room_left -= to_send;
1102        if (room_left < 0) {
1103            *len_sent = 0;
1104            audit_log_end(*ab);
1105            *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1106            if (!*ab)
1107                return 0;
1108        }
1109
1110        /*
1111         * first record needs to say how long the original string was
1112         * so we can be sure nothing was lost.
1113         */
1114        if ((i == 0) && (too_long))
1115            audit_log_format(*ab, " a%d_len=%zu", arg_num,
1116                     has_cntl ? 2*len : len);
1117
1118        /*
1119         * normally arguments are small enough to fit and we already
1120         * filled buf above when we checked for control characters
1121         * so don't bother with another copy_from_user
1122         */
1123        if (len >= max_execve_audit_len)
1124            ret = copy_from_user(buf, p, to_send);
1125        else
1126            ret = 0;
1127        if (ret) {
1128            WARN_ON(1);
1129            send_sig(SIGKILL, current, 0);
1130            return -1;
1131        }
1132        buf[to_send] = '\0';
1133
1134        /* actually log it */
1135        audit_log_format(*ab, " a%d", arg_num);
1136        if (too_long)
1137            audit_log_format(*ab, "[%d]", i);
1138        audit_log_format(*ab, "=");
1139        if (has_cntl)
1140            audit_log_n_hex(*ab, buf, to_send);
1141        else
1142            audit_log_string(*ab, buf);
1143
1144        p += to_send;
1145        len_left -= to_send;
1146        *len_sent += arg_num_len;
1147        if (has_cntl)
1148            *len_sent += to_send * 2;
1149        else
1150            *len_sent += to_send;
1151    }
1152    /* include the null we didn't log */
1153    return len + 1;
1154}
1155
1156static void audit_log_execve_info(struct audit_context *context,
1157                  struct audit_buffer **ab)
1158{
1159    int i, len;
1160    size_t len_sent = 0;
1161    const char __user *p;
1162    char *buf;
1163
1164    p = (const char __user *)current->mm->arg_start;
1165
1166    audit_log_format(*ab, "argc=%d", context->execve.argc);
1167
1168    /*
1169     * we need some kernel buffer to hold the userspace args. Just
1170     * allocate one big one rather than allocating one of the right size
1171     * for every single argument inside audit_log_single_execve_arg()
1172     * should be <8k allocation so should be pretty safe.
1173     */
1174    buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1175    if (!buf) {
1176        audit_panic("out of memory for argv string");
1177        return;
1178    }
1179
1180    for (i = 0; i < context->execve.argc; i++) {
1181        len = audit_log_single_execve_arg(context, ab, i,
1182                          &len_sent, p, buf);
1183        if (len <= 0)
1184            break;
1185        p += len;
1186    }
1187    kfree(buf);
1188}
1189
1190static void show_special(struct audit_context *context, int *call_panic)
1191{
1192    struct audit_buffer *ab;
1193    int i;
1194
1195    ab = audit_log_start(context, GFP_KERNEL, context->type);
1196    if (!ab)
1197        return;
1198
1199    switch (context->type) {
1200    case AUDIT_SOCKETCALL: {
1201        int nargs = context->socketcall.nargs;
1202        audit_log_format(ab, "nargs=%d", nargs);
1203        for (i = 0; i < nargs; i++)
1204            audit_log_format(ab, " a%d=%lx", i,
1205                context->socketcall.args[i]);
1206        break; }
1207    case AUDIT_IPC: {
1208        u32 osid = context->ipc.osid;
1209
1210        audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1211                 from_kuid(&init_user_ns, context->ipc.uid),
1212                 from_kgid(&init_user_ns, context->ipc.gid),
1213                 context->ipc.mode);
1214        if (osid) {
1215            char *ctx = NULL;
1216            u32 len;
1217            if (security_secid_to_secctx(osid, &ctx, &len)) {
1218                audit_log_format(ab, " osid=%u", osid);
1219                *call_panic = 1;
1220            } else {
1221                audit_log_format(ab, " obj=%s", ctx);
1222                security_release_secctx(ctx, len);
1223            }
1224        }
1225        if (context->ipc.has_perm) {
1226            audit_log_end(ab);
1227            ab = audit_log_start(context, GFP_KERNEL,
1228                         AUDIT_IPC_SET_PERM);
1229            if (unlikely(!ab))
1230                return;
1231            audit_log_format(ab,
1232                "qbytes=%lx ouid=%u ogid=%u mode=%#ho",
1233                context->ipc.qbytes,
1234                context->ipc.perm_uid,
1235                context->ipc.perm_gid,
1236                context->ipc.perm_mode);
1237        }
1238        break; }
1239    case AUDIT_MQ_OPEN: {
1240        audit_log_format(ab,
1241            "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
1242            "mq_msgsize=%ld mq_curmsgs=%ld",
1243            context->mq_open.oflag, context->mq_open.mode,
1244            context->mq_open.attr.mq_flags,
1245            context->mq_open.attr.mq_maxmsg,
1246            context->mq_open.attr.mq_msgsize,
1247            context->mq_open.attr.mq_curmsgs);
1248        break; }
1249    case AUDIT_MQ_SENDRECV: {
1250        audit_log_format(ab,
1251            "mqdes=%d msg_len=%zd msg_prio=%u "
1252            "abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1253            context->mq_sendrecv.mqdes,
1254            context->mq_sendrecv.msg_len,
1255            context->mq_sendrecv.msg_prio,
1256            context->mq_sendrecv.abs_timeout.tv_sec,
1257            context->mq_sendrecv.abs_timeout.tv_nsec);
1258        break; }
1259    case AUDIT_MQ_NOTIFY: {
1260        audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1261                context->mq_notify.mqdes,
1262                context->mq_notify.sigev_signo);
1263        break; }
1264    case AUDIT_MQ_GETSETATTR: {
1265        struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1266        audit_log_format(ab,
1267            "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1268            "mq_curmsgs=%ld ",
1269            context->mq_getsetattr.mqdes,
1270            attr->mq_flags, attr->mq_maxmsg,
1271            attr->mq_msgsize, attr->mq_curmsgs);
1272        break; }
1273    case AUDIT_CAPSET: {
1274        audit_log_format(ab, "pid=%d", context->capset.pid);
1275        audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1276        audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1277        audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1278        break; }
1279    case AUDIT_MMAP: {
1280        audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
1281                 context->mmap.flags);
1282        break; }
1283    case AUDIT_EXECVE: {
1284        audit_log_execve_info(context, &ab);
1285        break; }
1286    }
1287    audit_log_end(ab);
1288}
1289
1290static inline int audit_proctitle_rtrim(char *proctitle, int len)
1291{
1292    char *end = proctitle + len - 1;
1293    while (end > proctitle && !isprint(*end))
1294        end--;
1295
1296    /* catch the case where proctitle is only 1 non-print character */
1297    len = end - proctitle + 1;
1298    len -= isprint(proctitle[len-1]) == 0;
1299    return len;
1300}
1301
1302static void audit_log_proctitle(struct task_struct *tsk,
1303             struct audit_context *context)
1304{
1305    int res;
1306    char *buf;
1307    char *msg = "(null)";
1308    int len = strlen(msg);
1309    struct audit_buffer *ab;
1310
1311    ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE);
1312    if (!ab)
1313        return; /* audit_panic or being filtered */
1314
1315    audit_log_format(ab, "proctitle=");
1316
1317    /* Not cached */
1318    if (!context->proctitle.value) {
1319        buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL);
1320        if (!buf)
1321            goto out;
1322        /* Historically called this from procfs naming */
1323        res = get_cmdline(tsk, buf, MAX_PROCTITLE_AUDIT_LEN);
1324        if (res == 0) {
1325            kfree(buf);
1326            goto out;
1327        }
1328        res = audit_proctitle_rtrim(buf, res);
1329        if (res == 0) {
1330            kfree(buf);
1331            goto out;
1332        }
1333        context->proctitle.value = buf;
1334        context->proctitle.len = res;
1335    }
1336    msg = context->proctitle.value;
1337    len = context->proctitle.len;
1338out:
1339    audit_log_n_untrustedstring(ab, msg, len);
1340    audit_log_end(ab);
1341}
1342
1343static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1344{
1345    int i, call_panic = 0;
1346    struct audit_buffer *ab;
1347    struct audit_aux_data *aux;
1348    struct audit_names *n;
1349
1350    /* tsk == current */
1351    context->personality = tsk->personality;
1352
1353    ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1354    if (!ab)
1355        return; /* audit_panic has been called */
1356    audit_log_format(ab, "arch=%x syscall=%d",
1357             context->arch, context->major);
1358    if (context->personality != PER_LINUX)
1359        audit_log_format(ab, " per=%lx", context->personality);
1360    if (context->return_valid)
1361        audit_log_format(ab, " success=%s exit=%ld",
1362                 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1363                 context->return_code);
1364
1365    audit_log_format(ab,
1366             " a0=%lx a1=%lx a2=%lx a3=%lx items=%d",
1367             context->argv[0],
1368             context->argv[1],
1369             context->argv[2],
1370             context->argv[3],
1371             context->name_count);
1372
1373    audit_log_task_info(ab, tsk);
1374    audit_log_key(ab, context->filterkey);
1375    audit_log_end(ab);
1376
1377    for (aux = context->aux; aux; aux = aux->next) {
1378
1379        ab = audit_log_start(context, GFP_KERNEL, aux->type);
1380        if (!ab)
1381            continue; /* audit_panic has been called */
1382
1383        switch (aux->type) {
1384
1385        case AUDIT_BPRM_FCAPS: {
1386            struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1387            audit_log_format(ab, "fver=%x", axs->fcap_ver);
1388            audit_log_cap(ab, "fp", &axs->fcap.permitted);
1389            audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1390            audit_log_format(ab, " fe=%d", axs->fcap.fE);
1391            audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1392            audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1393            audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1394            audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
1395            audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
1396            audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
1397            break; }
1398
1399        }
1400        audit_log_end(ab);
1401    }
1402
1403    if (context->type)
1404        show_special(context, &call_panic);
1405
1406    if (context->fds[0] >= 0) {
1407        ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1408        if (ab) {
1409            audit_log_format(ab, "fd0=%d fd1=%d",
1410                    context->fds[0], context->fds[1]);
1411            audit_log_end(ab);
1412        }
1413    }
1414
1415    if (context->sockaddr_len) {
1416        ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1417        if (ab) {
1418            audit_log_format(ab, "saddr=");
1419            audit_log_n_hex(ab, (void *)context->sockaddr,
1420                    context->sockaddr_len);
1421            audit_log_end(ab);
1422        }
1423    }
1424
1425    for (aux = context->aux_pids; aux; aux = aux->next) {
1426        struct audit_aux_data_pids *axs = (void *)aux;
1427
1428        for (i = 0; i < axs->pid_count; i++)
1429            if (audit_log_pid_context(context, axs->target_pid[i],
1430                          axs->target_auid[i],
1431                          axs->target_uid[i],
1432                          axs->target_sessionid[i],
1433                          axs->target_sid[i],
1434                          axs->target_comm[i]))
1435                call_panic = 1;
1436    }
1437
1438    if (context->target_pid &&
1439        audit_log_pid_context(context, context->target_pid,
1440                  context->target_auid, context->target_uid,
1441                  context->target_sessionid,
1442                  context->target_sid, context->target_comm))
1443            call_panic = 1;
1444
1445    if (context->pwd.dentry && context->pwd.mnt) {
1446        ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1447        if (ab) {
1448            audit_log_d_path(ab, " cwd=", &context->pwd);
1449            audit_log_end(ab);
1450        }
1451    }
1452
1453    i = 0;
1454    list_for_each_entry(n, &context->names_list, list) {
1455        if (n->hidden)
1456            continue;
1457        audit_log_name(context, n, NULL, i++, &call_panic);
1458    }
1459
1460    audit_log_proctitle(tsk, context);
1461
1462    /* Send end of event record to help user space know we are finished */
1463    ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1464    if (ab)
1465        audit_log_end(ab);
1466    if (call_panic)
1467        audit_panic("error converting sid to string");
1468}
1469
1470/**
1471 * audit_free - free a per-task audit context
1472 * @tsk: task whose audit context block to free
1473 *
1474 * Called from copy_process and do_exit
1475 */
1476void __audit_free(struct task_struct *tsk)
1477{
1478    struct audit_context *context;
1479
1480    context = audit_take_context(tsk, 0, 0);
1481    if (!context)
1482        return;
1483
1484    /* Check for system calls that do not go through the exit
1485     * function (e.g., exit_group), then free context block.
1486     * We use GFP_ATOMIC here because we might be doing this
1487     * in the context of the idle thread */
1488    /* that can happen only if we are called from do_exit() */
1489    if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1490        audit_log_exit(context, tsk);
1491    if (!list_empty(&context->killed_trees))
1492        audit_kill_trees(&context->killed_trees);
1493
1494    audit_free_context(context);
1495}
1496
1497/**
1498 * audit_syscall_entry - fill in an audit record at syscall entry
1499 * @arch: architecture type
1500 * @major: major syscall type (function)
1501 * @a1: additional syscall register 1
1502 * @a2: additional syscall register 2
1503 * @a3: additional syscall register 3
1504 * @a4: additional syscall register 4
1505 *
1506 * Fill in audit context at syscall entry. This only happens if the
1507 * audit context was created when the task was created and the state or
1508 * filters demand the audit context be built. If the state from the
1509 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1510 * then the record will be written at syscall exit time (otherwise, it
1511 * will only be written if another part of the kernel requests that it
1512 * be written).
1513 */
1514void __audit_syscall_entry(int arch, int major,
1515             unsigned long a1, unsigned long a2,
1516             unsigned long a3, unsigned long a4)
1517{
1518    struct task_struct *tsk = current;
1519    struct audit_context *context = tsk->audit_context;
1520    enum audit_state state;
1521
1522    if (!context)
1523        return;
1524
1525    BUG_ON(context->in_syscall || context->name_count);
1526
1527    if (!audit_enabled)
1528        return;
1529
1530    context->arch = arch;
1531    context->major = major;
1532    context->argv[0] = a1;
1533    context->argv[1] = a2;
1534    context->argv[2] = a3;
1535    context->argv[3] = a4;
1536
1537    state = context->state;
1538    context->dummy = !audit_n_rules;
1539    if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
1540        context->prio = 0;
1541        state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1542    }
1543    if (state == AUDIT_DISABLED)
1544        return;
1545
1546    context->serial = 0;
1547    context->ctime = CURRENT_TIME;
1548    context->in_syscall = 1;
1549    context->current_state = state;
1550    context->ppid = 0;
1551}
1552
1553/**
1554 * audit_syscall_exit - deallocate audit context after a system call
1555 * @success: success value of the syscall
1556 * @return_code: return value of the syscall
1557 *
1558 * Tear down after system call. If the audit context has been marked as
1559 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1560 * filtering, or because some other part of the kernel wrote an audit
1561 * message), then write out the syscall information. In call cases,
1562 * free the names stored from getname().
1563 */
1564void __audit_syscall_exit(int success, long return_code)
1565{
1566    struct task_struct *tsk = current;
1567    struct audit_context *context;
1568
1569    if (success)
1570        success = AUDITSC_SUCCESS;
1571    else
1572        success = AUDITSC_FAILURE;
1573
1574    context = audit_take_context(tsk, success, return_code);
1575    if (!context)
1576        return;
1577
1578    if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1579        audit_log_exit(context, tsk);
1580
1581    context->in_syscall = 0;
1582    context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1583
1584    if (!list_empty(&context->killed_trees))
1585        audit_kill_trees(&context->killed_trees);
1586
1587    audit_free_names(context);
1588    unroll_tree_refs(context, NULL, 0);
1589    audit_free_aux(context);
1590    context->aux = NULL;
1591    context->aux_pids = NULL;
1592    context->target_pid = 0;
1593    context->target_sid = 0;
1594    context->sockaddr_len = 0;
1595    context->type = 0;
1596    context->fds[0] = -1;
1597    if (context->state != AUDIT_RECORD_CONTEXT) {
1598        kfree(context->filterkey);
1599        context->filterkey = NULL;
1600    }
1601    tsk->audit_context = context;
1602}
1603
1604static inline void handle_one(const struct inode *inode)
1605{
1606#ifdef CONFIG_AUDIT_TREE
1607    struct audit_context *context;
1608    struct audit_tree_refs *p;
1609    struct audit_chunk *chunk;
1610    int count;
1611    if (likely(hlist_empty(&inode->i_fsnotify_marks)))
1612        return;
1613    context = current->audit_context;
1614    p = context->trees;
1615    count = context->tree_count;
1616    rcu_read_lock();
1617    chunk = audit_tree_lookup(inode);
1618    rcu_read_unlock();
1619    if (!chunk)
1620        return;
1621    if (likely(put_tree_ref(context, chunk)))
1622        return;
1623    if (unlikely(!grow_tree_refs(context))) {
1624        pr_warn("out of memory, audit has lost a tree reference\n");
1625        audit_set_auditable(context);
1626        audit_put_chunk(chunk);
1627        unroll_tree_refs(context, p, count);
1628        return;
1629    }
1630    put_tree_ref(context, chunk);
1631#endif
1632}
1633
1634static void handle_path(const struct dentry *dentry)
1635{
1636#ifdef CONFIG_AUDIT_TREE
1637    struct audit_context *context;
1638    struct audit_tree_refs *p;
1639    const struct dentry *d, *parent;
1640    struct audit_chunk *drop;
1641    unsigned long seq;
1642    int count;
1643
1644    context = current->audit_context;
1645    p = context->trees;
1646    count = context->tree_count;
1647retry:
1648    drop = NULL;
1649    d = dentry;
1650    rcu_read_lock();
1651    seq = read_seqbegin(&rename_lock);
1652    for(;;) {
1653        struct inode *inode = d->d_inode;
1654        if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
1655            struct audit_chunk *chunk;
1656            chunk = audit_tree_lookup(inode);
1657            if (chunk) {
1658                if (unlikely(!put_tree_ref(context, chunk))) {
1659                    drop = chunk;
1660                    break;
1661                }
1662            }
1663        }
1664        parent = d->d_parent;
1665        if (parent == d)
1666            break;
1667        d = parent;
1668    }
1669    if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */
1670        rcu_read_unlock();
1671        if (!drop) {
1672            /* just a race with rename */
1673            unroll_tree_refs(context, p, count);
1674            goto retry;
1675        }
1676        audit_put_chunk(drop);
1677        if (grow_tree_refs(context)) {
1678            /* OK, got more space */
1679            unroll_tree_refs(context, p, count);
1680            goto retry;
1681        }
1682        /* too bad */
1683        pr_warn("out of memory, audit has lost a tree reference\n");
1684        unroll_tree_refs(context, p, count);
1685        audit_set_auditable(context);
1686        return;
1687    }
1688    rcu_read_unlock();
1689#endif
1690}
1691
1692static struct audit_names *audit_alloc_name(struct audit_context *context,
1693                        unsigned char type)
1694{
1695    struct audit_names *aname;
1696
1697    if (context->name_count < AUDIT_NAMES) {
1698        aname = &context->preallocated_names[context->name_count];
1699        memset(aname, 0, sizeof(*aname));
1700    } else {
1701        aname = kzalloc(sizeof(*aname), GFP_NOFS);
1702        if (!aname)
1703            return NULL;
1704        aname->should_free = true;
1705    }
1706
1707    aname->ino = (unsigned long)-1;
1708    aname->type = type;
1709    list_add_tail(&aname->list, &context->names_list);
1710
1711    context->name_count++;
1712#if AUDIT_DEBUG
1713    context->ino_count++;
1714#endif
1715    return aname;
1716}
1717
1718/**
1719 * audit_reusename - fill out filename with info from existing entry
1720 * @uptr: userland ptr to pathname
1721 *
1722 * Search the audit_names list for the current audit context. If there is an
1723 * existing entry with a matching "uptr" then return the filename
1724 * associated with that audit_name. If not, return NULL.
1725 */
1726struct filename *
1727__audit_reusename(const __user char *uptr)
1728{
1729    struct audit_context *context = current->audit_context;
1730    struct audit_names *n;
1731
1732    list_for_each_entry(n, &context->names_list, list) {
1733        if (!n->name)
1734            continue;
1735        if (n->name->uptr == uptr)
1736            return n->name;
1737    }
1738    return NULL;
1739}
1740
1741/**
1742 * audit_getname - add a name to the list
1743 * @name: name to add
1744 *
1745 * Add a name to the list of audit names for this context.
1746 * Called from fs/namei.c:getname().
1747 */
1748void __audit_getname(struct filename *name)
1749{
1750    struct audit_context *context = current->audit_context;
1751    struct audit_names *n;
1752
1753    if (!context->in_syscall) {
1754#if AUDIT_DEBUG == 2
1755        pr_err("%s:%d(:%d): ignoring getname(%p)\n",
1756               __FILE__, __LINE__, context->serial, name);
1757        dump_stack();
1758#endif
1759        return;
1760    }
1761
1762#if AUDIT_DEBUG
1763    /* The filename _must_ have a populated ->name */
1764    BUG_ON(!name->name);
1765#endif
1766
1767    n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
1768    if (!n)
1769        return;
1770
1771    n->name = name;
1772    n->name_len = AUDIT_NAME_FULL;
1773    n->name_put = true;
1774    name->aname = n;
1775
1776    if (!context->pwd.dentry)
1777        get_fs_pwd(current->fs, &context->pwd);
1778}
1779
1780/* audit_putname - intercept a putname request
1781 * @name: name to intercept and delay for putname
1782 *
1783 * If we have stored the name from getname in the audit context,
1784 * then we delay the putname until syscall exit.
1785 * Called from include/linux/fs.h:putname().
1786 */
1787void audit_putname(struct filename *name)
1788{
1789    struct audit_context *context = current->audit_context;
1790
1791    BUG_ON(!context);
1792    if (!name->aname || !context->in_syscall) {
1793#if AUDIT_DEBUG == 2
1794        pr_err("%s:%d(:%d): final_putname(%p)\n",
1795               __FILE__, __LINE__, context->serial, name);
1796        if (context->name_count) {
1797            struct audit_names *n;
1798            int i = 0;
1799
1800            list_for_each_entry(n, &context->names_list, list)
1801                pr_err("name[%d] = %p = %s\n", i++, n->name,
1802                       n->name->name ?: "(null)");
1803            }
1804#endif
1805        final_putname(name);
1806    }
1807#if AUDIT_DEBUG
1808    else {
1809        ++context->put_count;
1810        if (context->put_count > context->name_count) {
1811            pr_err("%s:%d(:%d): major=%d in_syscall=%d putname(%p)"
1812                   " name_count=%d put_count=%d\n",
1813                   __FILE__, __LINE__,
1814                   context->serial, context->major,
1815                   context->in_syscall, name->name,
1816                   context->name_count, context->put_count);
1817            dump_stack();
1818        }
1819    }
1820#endif
1821}
1822
1823/**
1824 * __audit_inode - store the inode and device from a lookup
1825 * @name: name being audited
1826 * @dentry: dentry being audited
1827 * @flags: attributes for this particular entry
1828 */
1829void __audit_inode(struct filename *name, const struct dentry *dentry,
1830           unsigned int flags)
1831{
1832    struct audit_context *context = current->audit_context;
1833    const struct inode *inode = dentry->d_inode;
1834    struct audit_names *n;
1835    bool parent = flags & AUDIT_INODE_PARENT;
1836
1837    if (!context->in_syscall)
1838        return;
1839
1840    if (!name)
1841        goto out_alloc;
1842
1843#if AUDIT_DEBUG
1844    /* The struct filename _must_ have a populated ->name */
1845    BUG_ON(!name->name);
1846#endif
1847    /*
1848     * If we have a pointer to an audit_names entry already, then we can
1849     * just use it directly if the type is correct.
1850     */
1851    n = name->aname;
1852    if (n) {
1853        if (parent) {
1854            if (n->type == AUDIT_TYPE_PARENT ||
1855                n->type == AUDIT_TYPE_UNKNOWN)
1856                goto out;
1857        } else {
1858            if (n->type != AUDIT_TYPE_PARENT)
1859                goto out;
1860        }
1861    }
1862
1863    list_for_each_entry_reverse(n, &context->names_list, list) {
1864        /* does the name pointer match? */
1865        if (!n->name || n->name->name != name->name)
1866            continue;
1867
1868        /* match the correct record type */
1869        if (parent) {
1870            if (n->type == AUDIT_TYPE_PARENT ||
1871                n->type == AUDIT_TYPE_UNKNOWN)
1872                goto out;
1873        } else {
1874            if (n->type != AUDIT_TYPE_PARENT)
1875                goto out;
1876        }
1877    }
1878
1879out_alloc:
1880    /* unable to find the name from a previous getname(). Allocate a new
1881     * anonymous entry.
1882     */
1883    n = audit_alloc_name(context, AUDIT_TYPE_NORMAL);
1884    if (!n)
1885        return;
1886out:
1887    if (parent) {
1888        n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
1889        n->type = AUDIT_TYPE_PARENT;
1890        if (flags & AUDIT_INODE_HIDDEN)
1891            n->hidden = true;
1892    } else {
1893        n->name_len = AUDIT_NAME_FULL;
1894        n->type = AUDIT_TYPE_NORMAL;
1895    }
1896    handle_path(dentry);
1897    audit_copy_inode(n, dentry, inode);
1898}
1899
1900/**
1901 * __audit_inode_child - collect inode info for created/removed objects
1902 * @parent: inode of dentry parent
1903 * @dentry: dentry being audited
1904 * @type: AUDIT_TYPE_* value that we're looking for
1905 *
1906 * For syscalls that create or remove filesystem objects, audit_inode
1907 * can only collect information for the filesystem object's parent.
1908 * This call updates the audit context with the child's information.
1909 * Syscalls that create a new filesystem object must be hooked after
1910 * the object is created. Syscalls that remove a filesystem object
1911 * must be hooked prior, in order to capture the target inode during
1912 * unsuccessful attempts.
1913 */
1914void __audit_inode_child(const struct inode *parent,
1915             const struct dentry *dentry,
1916             const unsigned char type)
1917{
1918    struct audit_context *context = current->audit_context;
1919    const struct inode *inode = dentry->d_inode;
1920    const char *dname = dentry->d_name.name;
1921    struct audit_names *n, *found_parent = NULL, *found_child = NULL;
1922
1923    if (!context->in_syscall)
1924        return;
1925
1926    if (inode)
1927        handle_one(inode);
1928
1929    /* look for a parent entry first */
1930    list_for_each_entry(n, &context->names_list, list) {
1931        if (!n->name || n->type != AUDIT_TYPE_PARENT)
1932            continue;
1933
1934        if (n->ino == parent->i_ino &&
1935            !audit_compare_dname_path(dname, n->name->name, n->name_len)) {
1936            found_parent = n;
1937            break;
1938        }
1939    }
1940
1941    /* is there a matching child entry? */
1942    list_for_each_entry(n, &context->names_list, list) {
1943        /* can only match entries that have a name */
1944        if (!n->name || n->type != type)
1945            continue;
1946
1947        /* if we found a parent, make sure this one is a child of it */
1948        if (found_parent && (n->name != found_parent->name))
1949            continue;
1950
1951        if (!strcmp(dname, n->name->name) ||
1952            !audit_compare_dname_path(dname, n->name->name,
1953                        found_parent ?
1954                        found_parent->name_len :
1955                        AUDIT_NAME_FULL)) {
1956            found_child = n;
1957            break;
1958        }
1959    }
1960
1961    if (!found_parent) {
1962        /* create a new, "anonymous" parent record */
1963        n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
1964        if (!n)
1965            return;
1966        audit_copy_inode(n, NULL, parent);
1967    }
1968
1969    if (!found_child) {
1970        found_child = audit_alloc_name(context, type);
1971        if (!found_child)
1972            return;
1973
1974        /* Re-use the name belonging to the slot for a matching parent
1975         * directory. All names for this context are relinquished in
1976         * audit_free_names() */
1977        if (found_parent) {
1978            found_child->name = found_parent->name;
1979            found_child->name_len = AUDIT_NAME_FULL;
1980            /* don't call __putname() */
1981            found_child->name_put = false;
1982        }
1983    }
1984    if (inode)
1985        audit_copy_inode(found_child, dentry, inode);
1986    else
1987        found_child->ino = (unsigned long)-1;
1988}
1989EXPORT_SYMBOL_GPL(__audit_inode_child);
1990
1991/**
1992 * auditsc_get_stamp - get local copies of audit_context values
1993 * @ctx: audit_context for the task
1994 * @t: timespec to store time recorded in the audit_context
1995 * @serial: serial value that is recorded in the audit_context
1996 *
1997 * Also sets the context as auditable.
1998 */
1999int auditsc_get_stamp(struct audit_context *ctx,
2000               struct timespec *t, unsigned int *serial)
2001{
2002    if (!ctx->in_syscall)
2003        return 0;
2004    if (!ctx->serial)
2005        ctx->serial = audit_serial();
2006    t->tv_sec = ctx->ctime.tv_sec;
2007    t->tv_nsec = ctx->ctime.tv_nsec;
2008    *serial = ctx->serial;
2009    if (!ctx->prio) {
2010        ctx->prio = 1;
2011        ctx->current_state = AUDIT_RECORD_CONTEXT;
2012    }
2013    return 1;
2014}
2015
2016/* global counter which is incremented every time something logs in */
2017static atomic_t session_id = ATOMIC_INIT(0);
2018
2019static int audit_set_loginuid_perm(kuid_t loginuid)
2020{
2021    /* if we are unset, we don't need privs */
2022    if (!audit_loginuid_set(current))
2023        return 0;
2024    /* if AUDIT_FEATURE_LOGINUID_IMMUTABLE means never ever allow a change*/
2025    if (is_audit_feature_set(AUDIT_FEATURE_LOGINUID_IMMUTABLE))
2026        return -EPERM;
2027    /* it is set, you need permission */
2028    if (!capable(CAP_AUDIT_CONTROL))
2029        return -EPERM;
2030    /* reject if this is not an unset and we don't allow that */
2031    if (is_audit_feature_set(AUDIT_FEATURE_ONLY_UNSET_LOGINUID) && uid_valid(loginuid))
2032        return -EPERM;
2033    return 0;
2034}
2035
2036static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid,
2037                   unsigned int oldsessionid, unsigned int sessionid,
2038                   int rc)
2039{
2040    struct audit_buffer *ab;
2041    uid_t uid, oldloginuid, loginuid;
2042
2043    if (!audit_enabled)
2044        return;
2045
2046    uid = from_kuid(&init_user_ns, task_uid(current));
2047    oldloginuid = from_kuid(&init_user_ns, koldloginuid);
2048    loginuid = from_kuid(&init_user_ns, kloginuid),
2049
2050    ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
2051    if (!ab)
2052        return;
2053    audit_log_format(ab, "pid=%d uid=%u", task_pid_nr(current), uid);
2054    audit_log_task_context(ab);
2055    audit_log_format(ab, " old-auid=%u auid=%u old-ses=%u ses=%u res=%d",
2056             oldloginuid, loginuid, oldsessionid, sessionid, !rc);
2057    audit_log_end(ab);
2058}
2059
2060/**
2061 * audit_set_loginuid - set current task's audit_context loginuid
2062 * @loginuid: loginuid value
2063 *
2064 * Returns 0.
2065 *
2066 * Called (set) from fs/proc/base.c::proc_loginuid_write().
2067 */
2068int audit_set_loginuid(kuid_t loginuid)
2069{
2070    struct task_struct *task = current;
2071    unsigned int oldsessionid, sessionid = (unsigned int)-1;
2072    kuid_t oldloginuid;
2073    int rc;
2074
2075    oldloginuid = audit_get_loginuid(current);
2076    oldsessionid = audit_get_sessionid(current);
2077
2078    rc = audit_set_loginuid_perm(loginuid);
2079    if (rc)
2080        goto out;
2081
2082    /* are we setting or clearing? */
2083    if (uid_valid(loginuid))
2084        sessionid = (unsigned int)atomic_inc_return(&session_id);
2085
2086    task->sessionid = sessionid;
2087    task->loginuid = loginuid;
2088out:
2089    audit_log_set_loginuid(oldloginuid, loginuid, oldsessionid, sessionid, rc);
2090    return rc;
2091}
2092
2093/**
2094 * __audit_mq_open - record audit data for a POSIX MQ open
2095 * @oflag: open flag
2096 * @mode: mode bits
2097 * @attr: queue attributes
2098 *
2099 */
2100void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2101{
2102    struct audit_context *context = current->audit_context;
2103
2104    if (attr)
2105        memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2106    else
2107        memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2108
2109    context->mq_open.oflag = oflag;
2110    context->mq_open.mode = mode;
2111
2112    context->type = AUDIT_MQ_OPEN;
2113}
2114
2115/**
2116 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2117 * @mqdes: MQ descriptor
2118 * @msg_len: Message length
2119 * @msg_prio: Message priority
2120 * @abs_timeout: Message timeout in absolute time
2121 *
2122 */
2123void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2124            const struct timespec *abs_timeout)
2125{
2126    struct audit_context *context = current->audit_context;
2127    struct timespec *p = &context->mq_sendrecv.abs_timeout;
2128
2129    if (abs_timeout)
2130        memcpy(p, abs_timeout, sizeof(struct timespec));
2131    else
2132        memset(p, 0, sizeof(struct timespec));
2133
2134    context->mq_sendrecv.mqdes = mqdes;
2135    context->mq_sendrecv.msg_len = msg_len;
2136    context->mq_sendrecv.msg_prio = msg_prio;
2137
2138    context->type = AUDIT_MQ_SENDRECV;
2139}
2140
2141/**
2142 * __audit_mq_notify - record audit data for a POSIX MQ notify
2143 * @mqdes: MQ descriptor
2144 * @notification: Notification event
2145 *
2146 */
2147
2148void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2149{
2150    struct audit_context *context = current->audit_context;
2151
2152    if (notification)
2153        context->mq_notify.sigev_signo = notification->sigev_signo;
2154    else
2155        context->mq_notify.sigev_signo = 0;
2156
2157    context->mq_notify.mqdes = mqdes;
2158    context->type = AUDIT_MQ_NOTIFY;
2159}
2160
2161/**
2162 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2163 * @mqdes: MQ descriptor
2164 * @mqstat: MQ flags
2165 *
2166 */
2167void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2168{
2169    struct audit_context *context = current->audit_context;
2170    context->mq_getsetattr.mqdes = mqdes;
2171    context->mq_getsetattr.mqstat = *mqstat;
2172    context->type = AUDIT_MQ_GETSETATTR;
2173}
2174
2175/**
2176 * audit_ipc_obj - record audit data for ipc object
2177 * @ipcp: ipc permissions
2178 *
2179 */
2180void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2181{
2182    struct audit_context *context = current->audit_context;
2183    context->ipc.uid = ipcp->uid;
2184    context->ipc.gid = ipcp->gid;
2185    context->ipc.mode = ipcp->mode;
2186    context->ipc.has_perm = 0;
2187    security_ipc_getsecid(ipcp, &context->ipc.osid);
2188    context->type = AUDIT_IPC;
2189}
2190
2191/**
2192 * audit_ipc_set_perm - record audit data for new ipc permissions
2193 * @qbytes: msgq bytes
2194 * @uid: msgq user id
2195 * @gid: msgq group id
2196 * @mode: msgq mode (permissions)
2197 *
2198 * Called only after audit_ipc_obj().
2199 */
2200void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
2201{
2202    struct audit_context *context = current->audit_context;
2203
2204    context->ipc.qbytes = qbytes;
2205    context->ipc.perm_uid = uid;
2206    context->ipc.perm_gid = gid;
2207    context->ipc.perm_mode = mode;
2208    context->ipc.has_perm = 1;
2209}
2210
2211void __audit_bprm(struct linux_binprm *bprm)
2212{
2213    struct audit_context *context = current->audit_context;
2214
2215    context->type = AUDIT_EXECVE;
2216    context->execve.argc = bprm->argc;
2217}
2218
2219
2220/**
2221 * audit_socketcall - record audit data for sys_socketcall
2222 * @nargs: number of args, which should not be more than AUDITSC_ARGS.
2223 * @args: args array
2224 *
2225 */
2226int __audit_socketcall(int nargs, unsigned long *args)
2227{
2228    struct audit_context *context = current->audit_context;
2229
2230    if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
2231        return -EINVAL;
2232    context->type = AUDIT_SOCKETCALL;
2233    context->socketcall.nargs = nargs;
2234    memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2235    return 0;
2236}
2237
2238/**
2239 * __audit_fd_pair - record audit data for pipe and socketpair
2240 * @fd1: the first file descriptor
2241 * @fd2: the second file descriptor
2242 *
2243 */
2244void __audit_fd_pair(int fd1, int fd2)
2245{
2246    struct audit_context *context = current->audit_context;
2247    context->fds[0] = fd1;
2248    context->fds[1] = fd2;
2249}
2250
2251/**
2252 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2253 * @len: data length in user space
2254 * @a: data address in kernel space
2255 *
2256 * Returns 0 for success or NULL context or < 0 on error.
2257 */
2258int __audit_sockaddr(int len, void *a)
2259{
2260    struct audit_context *context = current->audit_context;
2261
2262    if (!context->sockaddr) {
2263        void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2264        if (!p)
2265            return -ENOMEM;
2266        context->sockaddr = p;
2267    }
2268
2269    context->sockaddr_len = len;
2270    memcpy(context->sockaddr, a, len);
2271    return 0;
2272}
2273
2274void __audit_ptrace(struct task_struct *t)
2275{
2276    struct audit_context *context = current->audit_context;
2277
2278    context->target_pid = task_pid_nr(t);
2279    context->target_auid = audit_get_loginuid(t);
2280    context->target_uid = task_uid(t);
2281    context->target_sessionid = audit_get_sessionid(t);
2282    security_task_getsecid(t, &context->target_sid);
2283    memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2284}
2285
2286/**
2287 * audit_signal_info - record signal info for shutting down audit subsystem
2288 * @sig: signal value
2289 * @t: task being signaled
2290 *
2291 * If the audit subsystem is being terminated, record the task (pid)
2292 * and uid that is doing that.
2293 */
2294int __audit_signal_info(int sig, struct task_struct *t)
2295{
2296    struct audit_aux_data_pids *axp;
2297    struct task_struct *tsk = current;
2298    struct audit_context *ctx = tsk->audit_context;
2299    kuid_t uid = current_uid(), t_uid = task_uid(t);
2300
2301    if (audit_pid && t->tgid == audit_pid) {
2302        if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
2303            audit_sig_pid = task_pid_nr(tsk);
2304            if (uid_valid(tsk->loginuid))
2305                audit_sig_uid = tsk->loginuid;
2306            else
2307                audit_sig_uid = uid;
2308            security_task_getsecid(tsk, &audit_sig_sid);
2309        }
2310        if (!audit_signals || audit_dummy_context())
2311            return 0;
2312    }
2313
2314    /* optimize the common case by putting first signal recipient directly
2315     * in audit_context */
2316    if (!ctx->target_pid) {
2317        ctx->target_pid = task_tgid_nr(t);
2318        ctx->target_auid = audit_get_loginuid(t);
2319        ctx->target_uid = t_uid;
2320        ctx->target_sessionid = audit_get_sessionid(t);
2321        security_task_getsecid(t, &ctx->target_sid);
2322        memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2323        return 0;
2324    }
2325
2326    axp = (void *)ctx->aux_pids;
2327    if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2328        axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2329        if (!axp)
2330            return -ENOMEM;
2331
2332        axp->d.type = AUDIT_OBJ_PID;
2333        axp->d.next = ctx->aux_pids;
2334        ctx->aux_pids = (void *)axp;
2335    }
2336    BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2337
2338    axp->target_pid[axp->pid_count] = task_tgid_nr(t);
2339    axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2340    axp->target_uid[axp->pid_count] = t_uid;
2341    axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2342    security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2343    memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2344    axp->pid_count++;
2345
2346    return 0;
2347}
2348
2349/**
2350 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2351 * @bprm: pointer to the bprm being processed
2352 * @new: the proposed new credentials
2353 * @old: the old credentials
2354 *
2355 * Simply check if the proc already has the caps given by the file and if not
2356 * store the priv escalation info for later auditing at the end of the syscall
2357 *
2358 * -Eric
2359 */
2360int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2361               const struct cred *new, const struct cred *old)
2362{
2363    struct audit_aux_data_bprm_fcaps *ax;
2364    struct audit_context *context = current->audit_context;
2365    struct cpu_vfs_cap_data vcaps;
2366    struct dentry *dentry;
2367
2368    ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2369    if (!ax)
2370        return -ENOMEM;
2371
2372    ax->d.type = AUDIT_BPRM_FCAPS;
2373    ax->d.next = context->aux;
2374    context->aux = (void *)ax;
2375
2376    dentry = dget(bprm->file->f_dentry);
2377    get_vfs_caps_from_disk(dentry, &vcaps);
2378    dput(dentry);
2379
2380    ax->fcap.permitted = vcaps.permitted;
2381    ax->fcap.inheritable = vcaps.inheritable;
2382    ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2383    ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2384
2385    ax->old_pcap.permitted = old->cap_permitted;
2386    ax->old_pcap.inheritable = old->cap_inheritable;
2387    ax->old_pcap.effective = old->cap_effective;
2388
2389    ax->new_pcap.permitted = new->cap_permitted;
2390    ax->new_pcap.inheritable = new->cap_inheritable;
2391    ax->new_pcap.effective = new->cap_effective;
2392    return 0;
2393}
2394
2395/**
2396 * __audit_log_capset - store information about the arguments to the capset syscall
2397 * @new: the new credentials
2398 * @old: the old (current) credentials
2399 *
2400 * Record the aguments userspace sent to sys_capset for later printing by the
2401 * audit system if applicable
2402 */
2403void __audit_log_capset(const struct cred *new, const struct cred *old)
2404{
2405    struct audit_context *context = current->audit_context;
2406    context->capset.pid = task_pid_nr(current);
2407    context->capset.cap.effective = new->cap_effective;
2408    context->capset.cap.inheritable = new->cap_effective;
2409    context->capset.cap.permitted = new->cap_permitted;
2410    context->type = AUDIT_CAPSET;
2411}
2412
2413void __audit_mmap_fd(int fd, int flags)
2414{
2415    struct audit_context *context = current->audit_context;
2416    context->mmap.fd = fd;
2417    context->mmap.flags = flags;
2418    context->type = AUDIT_MMAP;
2419}
2420
2421static void audit_log_task(struct audit_buffer *ab)
2422{
2423    kuid_t auid, uid;
2424    kgid_t gid;
2425    unsigned int sessionid;
2426    struct mm_struct *mm = current->mm;
2427
2428    auid = audit_get_loginuid(current);
2429    sessionid = audit_get_sessionid(current);
2430    current_uid_gid(&uid, &gid);
2431
2432    audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2433             from_kuid(&init_user_ns, auid),
2434             from_kuid(&init_user_ns, uid),
2435             from_kgid(&init_user_ns, gid),
2436             sessionid);
2437    audit_log_task_context(ab);
2438    audit_log_format(ab, " pid=%d comm=", task_pid_nr(current));
2439    audit_log_untrustedstring(ab, current->comm);
2440    if (mm) {
2441        down_read(&mm->mmap_sem);
2442        if (mm->exe_file)
2443            audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
2444        up_read(&mm->mmap_sem);
2445    } else
2446        audit_log_format(ab, " exe=(null)");
2447}
2448
2449/**
2450 * audit_core_dumps - record information about processes that end abnormally
2451 * @signr: signal value
2452 *
2453 * If a process ends with a core dump, something fishy is going on and we
2454 * should record the event for investigation.
2455 */
2456void audit_core_dumps(long signr)
2457{
2458    struct audit_buffer *ab;
2459
2460    if (!audit_enabled)
2461        return;
2462
2463    if (signr == SIGQUIT) /* don't care for those */
2464        return;
2465
2466    ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2467    if (unlikely(!ab))
2468        return;
2469    audit_log_task(ab);
2470    audit_log_format(ab, " sig=%ld", signr);
2471    audit_log_end(ab);
2472}
2473
2474void __audit_seccomp(unsigned long syscall, long signr, int code)
2475{
2476    struct audit_buffer *ab;
2477
2478    ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP);
2479    if (unlikely(!ab))
2480        return;
2481    audit_log_task(ab);
2482    audit_log_format(ab, " sig=%ld", signr);
2483    audit_log_format(ab, " syscall=%ld", syscall);
2484    audit_log_format(ab, " compat=%d", is_compat_task());
2485    audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current));
2486    audit_log_format(ab, " code=0x%x", code);
2487    audit_log_end(ab);
2488}
2489
2490struct list_head *audit_killed_trees(void)
2491{
2492    struct audit_context *ctx = current->audit_context;
2493    if (likely(!ctx || !ctx->in_syscall))
2494        return NULL;
2495    return &ctx->killed_trees;
2496}
2497

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