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#include <linux/init.h>
46#include <asm/types.h>
47#include <asm/atomic.h>
48#include <linux/fs.h>
49#include <linux/namei.h>
50#include <linux/mm.h>
51#include <linux/module.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
71#include "audit.h"
72
73/* AUDIT_NAMES is the number of slots we reserve in the audit_context
74 * for saving names from getname(). */
75#define AUDIT_NAMES 20
76
77/* Indicates that audit should log the full pathname. */
78#define AUDIT_NAME_FULL -1
79
80/* no execve audit message should be longer than this (userspace limits) */
81#define MAX_EXECVE_AUDIT_LEN 7500
82
83/* number of audit rules */
84int audit_n_rules;
85
86/* determines whether we collect data for signals sent */
87int audit_signals;
88
89struct audit_cap_data {
90    kernel_cap_t permitted;
91    kernel_cap_t inheritable;
92    union {
93        unsigned int fE; /* effective bit of a file capability */
94        kernel_cap_t effective; /* effective set of a process */
95    };
96};
97
98/* When fs/namei.c:getname() is called, we store the pointer in name and
99 * we don't let putname() free it (instead we free all of the saved
100 * pointers at syscall exit time).
101 *
102 * Further, in fs/namei.c:path_lookup() we store the inode and device. */
103struct audit_names {
104    const char *name;
105    int name_len; /* number of name's characters to log */
106    unsigned name_put; /* call __putname() for this name */
107    unsigned long ino;
108    dev_t dev;
109    umode_t mode;
110    uid_t uid;
111    gid_t gid;
112    dev_t rdev;
113    u32 osid;
114    struct audit_cap_data fcap;
115    unsigned int fcap_ver;
116};
117
118struct audit_aux_data {
119    struct audit_aux_data *next;
120    int type;
121};
122
123#define AUDIT_AUX_IPCPERM 0
124
125/* Number of target pids per aux struct. */
126#define AUDIT_AUX_PIDS 16
127
128struct audit_aux_data_execve {
129    struct audit_aux_data d;
130    int argc;
131    int envc;
132    struct mm_struct *mm;
133};
134
135struct audit_aux_data_pids {
136    struct audit_aux_data d;
137    pid_t target_pid[AUDIT_AUX_PIDS];
138    uid_t target_auid[AUDIT_AUX_PIDS];
139    uid_t target_uid[AUDIT_AUX_PIDS];
140    unsigned int target_sessionid[AUDIT_AUX_PIDS];
141    u32 target_sid[AUDIT_AUX_PIDS];
142    char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
143    int pid_count;
144};
145
146struct audit_aux_data_bprm_fcaps {
147    struct audit_aux_data d;
148    struct audit_cap_data fcap;
149    unsigned int fcap_ver;
150    struct audit_cap_data old_pcap;
151    struct audit_cap_data new_pcap;
152};
153
154struct audit_aux_data_capset {
155    struct audit_aux_data d;
156    pid_t pid;
157    struct audit_cap_data cap;
158};
159
160struct audit_tree_refs {
161    struct audit_tree_refs *next;
162    struct audit_chunk *c[31];
163};
164
165/* The per-task audit context. */
166struct audit_context {
167    int dummy; /* must be the first element */
168    int in_syscall; /* 1 if task is in a syscall */
169    enum audit_state state, current_state;
170    unsigned int serial; /* serial number for record */
171    int major; /* syscall number */
172    struct timespec ctime; /* time of syscall entry */
173    unsigned long argv[4]; /* syscall arguments */
174    long return_code;/* syscall return code */
175    u64 prio;
176    int return_valid; /* return code is valid */
177    int name_count;
178    struct audit_names names[AUDIT_NAMES];
179    char * filterkey; /* key for rule that triggered record */
180    struct path pwd;
181    struct audit_context *previous; /* For nested syscalls */
182    struct audit_aux_data *aux;
183    struct audit_aux_data *aux_pids;
184    struct sockaddr_storage *sockaddr;
185    size_t sockaddr_len;
186                /* Save things to print about task_struct */
187    pid_t pid, ppid;
188    uid_t uid, euid, suid, fsuid;
189    gid_t gid, egid, sgid, fsgid;
190    unsigned long personality;
191    int arch;
192
193    pid_t target_pid;
194    uid_t target_auid;
195    uid_t target_uid;
196    unsigned int target_sessionid;
197    u32 target_sid;
198    char target_comm[TASK_COMM_LEN];
199
200    struct audit_tree_refs *trees, *first_trees;
201    struct list_head killed_trees;
202    int tree_count;
203
204    int type;
205    union {
206        struct {
207            int nargs;
208            long args[6];
209        } socketcall;
210        struct {
211            uid_t uid;
212            gid_t gid;
213            mode_t mode;
214            u32 osid;
215            int has_perm;
216            uid_t perm_uid;
217            gid_t perm_gid;
218            mode_t perm_mode;
219            unsigned long qbytes;
220        } ipc;
221        struct {
222            mqd_t mqdes;
223            struct mq_attr mqstat;
224        } mq_getsetattr;
225        struct {
226            mqd_t mqdes;
227            int sigev_signo;
228        } mq_notify;
229        struct {
230            mqd_t mqdes;
231            size_t msg_len;
232            unsigned int msg_prio;
233            struct timespec abs_timeout;
234        } mq_sendrecv;
235        struct {
236            int oflag;
237            mode_t mode;
238            struct mq_attr attr;
239        } mq_open;
240        struct {
241            pid_t pid;
242            struct audit_cap_data cap;
243        } capset;
244    };
245    int fds[2];
246
247#if AUDIT_DEBUG
248    int put_count;
249    int ino_count;
250#endif
251};
252
253static inline int open_arg(int flags, int mask)
254{
255    int n = ACC_MODE(flags);
256    if (flags & (O_TRUNC | O_CREAT))
257        n |= AUDIT_PERM_WRITE;
258    return n & mask;
259}
260
261static int audit_match_perm(struct audit_context *ctx, int mask)
262{
263    unsigned n;
264    if (unlikely(!ctx))
265        return 0;
266    n = ctx->major;
267
268    switch (audit_classify_syscall(ctx->arch, n)) {
269    case 0: /* native */
270        if ((mask & AUDIT_PERM_WRITE) &&
271             audit_match_class(AUDIT_CLASS_WRITE, n))
272            return 1;
273        if ((mask & AUDIT_PERM_READ) &&
274             audit_match_class(AUDIT_CLASS_READ, n))
275            return 1;
276        if ((mask & AUDIT_PERM_ATTR) &&
277             audit_match_class(AUDIT_CLASS_CHATTR, n))
278            return 1;
279        return 0;
280    case 1: /* 32bit on biarch */
281        if ((mask & AUDIT_PERM_WRITE) &&
282             audit_match_class(AUDIT_CLASS_WRITE_32, n))
283            return 1;
284        if ((mask & AUDIT_PERM_READ) &&
285             audit_match_class(AUDIT_CLASS_READ_32, n))
286            return 1;
287        if ((mask & AUDIT_PERM_ATTR) &&
288             audit_match_class(AUDIT_CLASS_CHATTR_32, n))
289            return 1;
290        return 0;
291    case 2: /* open */
292        return mask & ACC_MODE(ctx->argv[1]);
293    case 3: /* openat */
294        return mask & ACC_MODE(ctx->argv[2]);
295    case 4: /* socketcall */
296        return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
297    case 5: /* execve */
298        return mask & AUDIT_PERM_EXEC;
299    default:
300        return 0;
301    }
302}
303
304static int audit_match_filetype(struct audit_context *ctx, int which)
305{
306    unsigned index = which & ~S_IFMT;
307    mode_t mode = which & S_IFMT;
308
309    if (unlikely(!ctx))
310        return 0;
311
312    if (index >= ctx->name_count)
313        return 0;
314    if (ctx->names[index].ino == -1)
315        return 0;
316    if ((ctx->names[index].mode ^ mode) & S_IFMT)
317        return 0;
318    return 1;
319}
320
321/*
322 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
323 * ->first_trees points to its beginning, ->trees - to the current end of data.
324 * ->tree_count is the number of free entries in array pointed to by ->trees.
325 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
326 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously,
327 * it's going to remain 1-element for almost any setup) until we free context itself.
328 * References in it _are_ dropped - at the same time we free/drop aux stuff.
329 */
330
331#ifdef CONFIG_AUDIT_TREE
332static void audit_set_auditable(struct audit_context *ctx)
333{
334    if (!ctx->prio) {
335        ctx->prio = 1;
336        ctx->current_state = AUDIT_RECORD_CONTEXT;
337    }
338}
339
340static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
341{
342    struct audit_tree_refs *p = ctx->trees;
343    int left = ctx->tree_count;
344    if (likely(left)) {
345        p->c[--left] = chunk;
346        ctx->tree_count = left;
347        return 1;
348    }
349    if (!p)
350        return 0;
351    p = p->next;
352    if (p) {
353        p->c[30] = chunk;
354        ctx->trees = p;
355        ctx->tree_count = 30;
356        return 1;
357    }
358    return 0;
359}
360
361static int grow_tree_refs(struct audit_context *ctx)
362{
363    struct audit_tree_refs *p = ctx->trees;
364    ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
365    if (!ctx->trees) {
366        ctx->trees = p;
367        return 0;
368    }
369    if (p)
370        p->next = ctx->trees;
371    else
372        ctx->first_trees = ctx->trees;
373    ctx->tree_count = 31;
374    return 1;
375}
376#endif
377
378static void unroll_tree_refs(struct audit_context *ctx,
379              struct audit_tree_refs *p, int count)
380{
381#ifdef CONFIG_AUDIT_TREE
382    struct audit_tree_refs *q;
383    int n;
384    if (!p) {
385        /* we started with empty chain */
386        p = ctx->first_trees;
387        count = 31;
388        /* if the very first allocation has failed, nothing to do */
389        if (!p)
390            return;
391    }
392    n = count;
393    for (q = p; q != ctx->trees; q = q->next, n = 31) {
394        while (n--) {
395            audit_put_chunk(q->c[n]);
396            q->c[n] = NULL;
397        }
398    }
399    while (n-- > ctx->tree_count) {
400        audit_put_chunk(q->c[n]);
401        q->c[n] = NULL;
402    }
403    ctx->trees = p;
404    ctx->tree_count = count;
405#endif
406}
407
408static void free_tree_refs(struct audit_context *ctx)
409{
410    struct audit_tree_refs *p, *q;
411    for (p = ctx->first_trees; p; p = q) {
412        q = p->next;
413        kfree(p);
414    }
415}
416
417static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
418{
419#ifdef CONFIG_AUDIT_TREE
420    struct audit_tree_refs *p;
421    int n;
422    if (!tree)
423        return 0;
424    /* full ones */
425    for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
426        for (n = 0; n < 31; n++)
427            if (audit_tree_match(p->c[n], tree))
428                return 1;
429    }
430    /* partial */
431    if (p) {
432        for (n = ctx->tree_count; n < 31; n++)
433            if (audit_tree_match(p->c[n], tree))
434                return 1;
435    }
436#endif
437    return 0;
438}
439
440/* Determine if any context name data matches a rule's watch data */
441/* Compare a task_struct with an audit_rule. Return 1 on match, 0
442 * otherwise. */
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{
449    const struct cred *cred = get_task_cred(tsk);
450    int i, j, need_sid = 1;
451    u32 sid;
452
453    for (i = 0; i < rule->field_count; i++) {
454        struct audit_field *f = &rule->fields[i];
455        int result = 0;
456
457        switch (f->type) {
458        case AUDIT_PID:
459            result = audit_comparator(tsk->pid, f->op, f->val);
460            break;
461        case AUDIT_PPID:
462            if (ctx) {
463                if (!ctx->ppid)
464                    ctx->ppid = sys_getppid();
465                result = audit_comparator(ctx->ppid, f->op, f->val);
466            }
467            break;
468        case AUDIT_UID:
469            result = audit_comparator(cred->uid, f->op, f->val);
470            break;
471        case AUDIT_EUID:
472            result = audit_comparator(cred->euid, f->op, f->val);
473            break;
474        case AUDIT_SUID:
475            result = audit_comparator(cred->suid, f->op, f->val);
476            break;
477        case AUDIT_FSUID:
478            result = audit_comparator(cred->fsuid, f->op, f->val);
479            break;
480        case AUDIT_GID:
481            result = audit_comparator(cred->gid, f->op, f->val);
482            break;
483        case AUDIT_EGID:
484            result = audit_comparator(cred->egid, f->op, f->val);
485            break;
486        case AUDIT_SGID:
487            result = audit_comparator(cred->sgid, f->op, f->val);
488            break;
489        case AUDIT_FSGID:
490            result = audit_comparator(cred->fsgid, f->op, f->val);
491            break;
492        case AUDIT_PERS:
493            result = audit_comparator(tsk->personality, f->op, f->val);
494            break;
495        case AUDIT_ARCH:
496            if (ctx)
497                result = audit_comparator(ctx->arch, f->op, f->val);
498            break;
499
500        case AUDIT_EXIT:
501            if (ctx && ctx->return_valid)
502                result = audit_comparator(ctx->return_code, f->op, f->val);
503            break;
504        case AUDIT_SUCCESS:
505            if (ctx && ctx->return_valid) {
506                if (f->val)
507                    result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
508                else
509                    result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
510            }
511            break;
512        case AUDIT_DEVMAJOR:
513            if (name)
514                result = audit_comparator(MAJOR(name->dev),
515                              f->op, f->val);
516            else if (ctx) {
517                for (j = 0; j < ctx->name_count; j++) {
518                    if (audit_comparator(MAJOR(ctx->names[j].dev), f->op, f->val)) {
519                        ++result;
520                        break;
521                    }
522                }
523            }
524            break;
525        case AUDIT_DEVMINOR:
526            if (name)
527                result = audit_comparator(MINOR(name->dev),
528                              f->op, f->val);
529            else if (ctx) {
530                for (j = 0; j < ctx->name_count; j++) {
531                    if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
532                        ++result;
533                        break;
534                    }
535                }
536            }
537            break;
538        case AUDIT_INODE:
539            if (name)
540                result = (name->ino == f->val);
541            else if (ctx) {
542                for (j = 0; j < ctx->name_count; j++) {
543                    if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
544                        ++result;
545                        break;
546                    }
547                }
548            }
549            break;
550        case AUDIT_WATCH:
551            if (name)
552                result = audit_watch_compare(rule->watch, name->ino, name->dev);
553            break;
554        case AUDIT_DIR:
555            if (ctx)
556                result = match_tree_refs(ctx, rule->tree);
557            break;
558        case AUDIT_LOGINUID:
559            result = 0;
560            if (ctx)
561                result = audit_comparator(tsk->loginuid, f->op, f->val);
562            break;
563        case AUDIT_SUBJ_USER:
564        case AUDIT_SUBJ_ROLE:
565        case AUDIT_SUBJ_TYPE:
566        case AUDIT_SUBJ_SEN:
567        case AUDIT_SUBJ_CLR:
568            /* NOTE: this may return negative values indicating
569               a temporary error. We simply treat this as a
570               match for now to avoid losing information that
571               may be wanted. An error message will also be
572               logged upon error */
573            if (f->lsm_rule) {
574                if (need_sid) {
575                    security_task_getsecid(tsk, &sid);
576                    need_sid = 0;
577                }
578                result = security_audit_rule_match(sid, f->type,
579                                                  f->op,
580                                                  f->lsm_rule,
581                                                  ctx);
582            }
583            break;
584        case AUDIT_OBJ_USER:
585        case AUDIT_OBJ_ROLE:
586        case AUDIT_OBJ_TYPE:
587        case AUDIT_OBJ_LEV_LOW:
588        case AUDIT_OBJ_LEV_HIGH:
589            /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
590               also applies here */
591            if (f->lsm_rule) {
592                /* Find files that match */
593                if (name) {
594                    result = security_audit_rule_match(
595                               name->osid, f->type, f->op,
596                               f->lsm_rule, ctx);
597                } else if (ctx) {
598                    for (j = 0; j < ctx->name_count; j++) {
599                        if (security_audit_rule_match(
600                              ctx->names[j].osid,
601                              f->type, f->op,
602                              f->lsm_rule, ctx)) {
603                            ++result;
604                            break;
605                        }
606                    }
607                }
608                /* Find ipc objects that match */
609                if (!ctx || ctx->type != AUDIT_IPC)
610                    break;
611                if (security_audit_rule_match(ctx->ipc.osid,
612                                  f->type, f->op,
613                                  f->lsm_rule, ctx))
614                    ++result;
615            }
616            break;
617        case AUDIT_ARG0:
618        case AUDIT_ARG1:
619        case AUDIT_ARG2:
620        case AUDIT_ARG3:
621            if (ctx)
622                result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
623            break;
624        case AUDIT_FILTERKEY:
625            /* ignore this field for filtering */
626            result = 1;
627            break;
628        case AUDIT_PERM:
629            result = audit_match_perm(ctx, f->val);
630            break;
631        case AUDIT_FILETYPE:
632            result = audit_match_filetype(ctx, f->val);
633            break;
634        }
635
636        if (!result) {
637            put_cred(cred);
638            return 0;
639        }
640    }
641
642    if (ctx) {
643        if (rule->prio <= ctx->prio)
644            return 0;
645        if (rule->filterkey) {
646            kfree(ctx->filterkey);
647            ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
648        }
649        ctx->prio = rule->prio;
650    }
651    switch (rule->action) {
652    case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
653    case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
654    }
655    put_cred(cred);
656    return 1;
657}
658
659/* At process creation time, we can determine if system-call auditing is
660 * completely disabled for this task. Since we only have the task
661 * structure at this point, we can only check uid and gid.
662 */
663static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
664{
665    struct audit_entry *e;
666    enum audit_state state;
667
668    rcu_read_lock();
669    list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
670        if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
671            if (state == AUDIT_RECORD_CONTEXT)
672                *key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
673            rcu_read_unlock();
674            return state;
675        }
676    }
677    rcu_read_unlock();
678    return AUDIT_BUILD_CONTEXT;
679}
680
681/* At syscall entry and exit time, this filter is called if the
682 * audit_state is not low enough that auditing cannot take place, but is
683 * also not high enough that we already know we have to write an audit
684 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
685 */
686static enum audit_state audit_filter_syscall(struct task_struct *tsk,
687                         struct audit_context *ctx,
688                         struct list_head *list)
689{
690    struct audit_entry *e;
691    enum audit_state state;
692
693    if (audit_pid && tsk->tgid == audit_pid)
694        return AUDIT_DISABLED;
695
696    rcu_read_lock();
697    if (!list_empty(list)) {
698        int word = AUDIT_WORD(ctx->major);
699        int bit = AUDIT_BIT(ctx->major);
700
701        list_for_each_entry_rcu(e, list, list) {
702            if ((e->rule.mask[word] & bit) == bit &&
703                audit_filter_rules(tsk, &e->rule, ctx, NULL,
704                           &state)) {
705                rcu_read_unlock();
706                ctx->current_state = state;
707                return state;
708            }
709        }
710    }
711    rcu_read_unlock();
712    return AUDIT_BUILD_CONTEXT;
713}
714
715/* At syscall exit time, this filter is called if any audit_names[] have been
716 * collected during syscall processing. We only check rules in sublists at hash
717 * buckets applicable to the inode numbers in audit_names[].
718 * Regarding audit_state, same rules apply as for audit_filter_syscall().
719 */
720void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
721{
722    int i;
723    struct audit_entry *e;
724    enum audit_state state;
725
726    if (audit_pid && tsk->tgid == audit_pid)
727        return;
728
729    rcu_read_lock();
730    for (i = 0; i < ctx->name_count; i++) {
731        int word = AUDIT_WORD(ctx->major);
732        int bit = AUDIT_BIT(ctx->major);
733        struct audit_names *n = &ctx->names[i];
734        int h = audit_hash_ino((u32)n->ino);
735        struct list_head *list = &audit_inode_hash[h];
736
737        if (list_empty(list))
738            continue;
739
740        list_for_each_entry_rcu(e, list, list) {
741            if ((e->rule.mask[word] & bit) == bit &&
742                audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
743                rcu_read_unlock();
744                ctx->current_state = state;
745                return;
746            }
747        }
748    }
749    rcu_read_unlock();
750}
751
752static inline struct audit_context *audit_get_context(struct task_struct *tsk,
753                              int return_valid,
754                              long return_code)
755{
756    struct audit_context *context = tsk->audit_context;
757
758    if (likely(!context))
759        return NULL;
760    context->return_valid = return_valid;
761
762    /*
763     * we need to fix up the return code in the audit logs if the actual
764     * return codes are later going to be fixed up by the arch specific
765     * signal handlers
766     *
767     * This is actually a test for:
768     * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
769     * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
770     *
771     * but is faster than a bunch of ||
772     */
773    if (unlikely(return_code <= -ERESTARTSYS) &&
774        (return_code >= -ERESTART_RESTARTBLOCK) &&
775        (return_code != -ENOIOCTLCMD))
776        context->return_code = -EINTR;
777    else
778        context->return_code = return_code;
779
780    if (context->in_syscall && !context->dummy) {
781        audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
782        audit_filter_inodes(tsk, context);
783    }
784
785    tsk->audit_context = NULL;
786    return context;
787}
788
789static inline void audit_free_names(struct audit_context *context)
790{
791    int i;
792
793#if AUDIT_DEBUG == 2
794    if (context->put_count + context->ino_count != context->name_count) {
795        printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
796               " name_count=%d put_count=%d"
797               " ino_count=%d [NOT freeing]\n",
798               __FILE__, __LINE__,
799               context->serial, context->major, context->in_syscall,
800               context->name_count, context->put_count,
801               context->ino_count);
802        for (i = 0; i < context->name_count; i++) {
803            printk(KERN_ERR "names[%d] = %p = %s\n", i,
804                   context->names[i].name,
805                   context->names[i].name ?: "(null)");
806        }
807        dump_stack();
808        return;
809    }
810#endif
811#if AUDIT_DEBUG
812    context->put_count = 0;
813    context->ino_count = 0;
814#endif
815
816    for (i = 0; i < context->name_count; i++) {
817        if (context->names[i].name && context->names[i].name_put)
818            __putname(context->names[i].name);
819    }
820    context->name_count = 0;
821    path_put(&context->pwd);
822    context->pwd.dentry = NULL;
823    context->pwd.mnt = NULL;
824}
825
826static inline void audit_free_aux(struct audit_context *context)
827{
828    struct audit_aux_data *aux;
829
830    while ((aux = context->aux)) {
831        context->aux = aux->next;
832        kfree(aux);
833    }
834    while ((aux = context->aux_pids)) {
835        context->aux_pids = aux->next;
836        kfree(aux);
837    }
838}
839
840static inline void audit_zero_context(struct audit_context *context,
841                      enum audit_state state)
842{
843    memset(context, 0, sizeof(*context));
844    context->state = state;
845    context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
846}
847
848static inline struct audit_context *audit_alloc_context(enum audit_state state)
849{
850    struct audit_context *context;
851
852    if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
853        return NULL;
854    audit_zero_context(context, state);
855    INIT_LIST_HEAD(&context->killed_trees);
856    return context;
857}
858
859/**
860 * audit_alloc - allocate an audit context block for a task
861 * @tsk: task
862 *
863 * Filter on the task information and allocate a per-task audit context
864 * if necessary. Doing so turns on system call auditing for the
865 * specified task. This is called from copy_process, so no lock is
866 * needed.
867 */
868int audit_alloc(struct task_struct *tsk)
869{
870    struct audit_context *context;
871    enum audit_state state;
872    char *key = NULL;
873
874    if (likely(!audit_ever_enabled))
875        return 0; /* Return if not auditing. */
876
877    state = audit_filter_task(tsk, &key);
878    if (likely(state == AUDIT_DISABLED))
879        return 0;
880
881    if (!(context = audit_alloc_context(state))) {
882        kfree(key);
883        audit_log_lost("out of memory in audit_alloc");
884        return -ENOMEM;
885    }
886    context->filterkey = key;
887
888    tsk->audit_context = context;
889    set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
890    return 0;
891}
892
893static inline void audit_free_context(struct audit_context *context)
894{
895    struct audit_context *previous;
896    int count = 0;
897
898    do {
899        previous = context->previous;
900        if (previous || (count && count < 10)) {
901            ++count;
902            printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
903                   " freeing multiple contexts (%d)\n",
904                   context->serial, context->major,
905                   context->name_count, count);
906        }
907        audit_free_names(context);
908        unroll_tree_refs(context, NULL, 0);
909        free_tree_refs(context);
910        audit_free_aux(context);
911        kfree(context->filterkey);
912        kfree(context->sockaddr);
913        kfree(context);
914        context = previous;
915    } while (context);
916    if (count >= 10)
917        printk(KERN_ERR "audit: freed %d contexts\n", count);
918}
919
920void audit_log_task_context(struct audit_buffer *ab)
921{
922    char *ctx = NULL;
923    unsigned len;
924    int error;
925    u32 sid;
926
927    security_task_getsecid(current, &sid);
928    if (!sid)
929        return;
930
931    error = security_secid_to_secctx(sid, &ctx, &len);
932    if (error) {
933        if (error != -EINVAL)
934            goto error_path;
935        return;
936    }
937
938    audit_log_format(ab, " subj=%s", ctx);
939    security_release_secctx(ctx, len);
940    return;
941
942error_path:
943    audit_panic("error in audit_log_task_context");
944    return;
945}
946
947EXPORT_SYMBOL(audit_log_task_context);
948
949static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
950{
951    char name[sizeof(tsk->comm)];
952    struct mm_struct *mm = tsk->mm;
953    struct vm_area_struct *vma;
954
955    /* tsk == current */
956
957    get_task_comm(name, tsk);
958    audit_log_format(ab, " comm=");
959    audit_log_untrustedstring(ab, name);
960
961    if (mm) {
962        down_read(&mm->mmap_sem);
963        vma = mm->mmap;
964        while (vma) {
965            if ((vma->vm_flags & VM_EXECUTABLE) &&
966                vma->vm_file) {
967                audit_log_d_path(ab, "exe=",
968                         &vma->vm_file->f_path);
969                break;
970            }
971            vma = vma->vm_next;
972        }
973        up_read(&mm->mmap_sem);
974    }
975    audit_log_task_context(ab);
976}
977
978static int audit_log_pid_context(struct audit_context *context, pid_t pid,
979                 uid_t auid, uid_t uid, unsigned int sessionid,
980                 u32 sid, char *comm)
981{
982    struct audit_buffer *ab;
983    char *ctx = NULL;
984    u32 len;
985    int rc = 0;
986
987    ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
988    if (!ab)
989        return rc;
990
991    audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
992             uid, sessionid);
993    if (security_secid_to_secctx(sid, &ctx, &len)) {
994        audit_log_format(ab, " obj=(none)");
995        rc = 1;
996    } else {
997        audit_log_format(ab, " obj=%s", ctx);
998        security_release_secctx(ctx, len);
999    }
1000    audit_log_format(ab, " ocomm=");
1001    audit_log_untrustedstring(ab, comm);
1002    audit_log_end(ab);
1003
1004    return rc;
1005}
1006
1007/*
1008 * to_send and len_sent accounting are very loose estimates. We aren't
1009 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
1010 * within about 500 bytes (next page boundry)
1011 *
1012 * why snprintf? an int is up to 12 digits long. if we just assumed when
1013 * logging that a[%d]= was going to be 16 characters long we would be wasting
1014 * space in every audit message. In one 7500 byte message we can log up to
1015 * about 1000 min size arguments. That comes down to about 50% waste of space
1016 * if we didn't do the snprintf to find out how long arg_num_len was.
1017 */
1018static int audit_log_single_execve_arg(struct audit_context *context,
1019                    struct audit_buffer **ab,
1020                    int arg_num,
1021                    size_t *len_sent,
1022                    const char __user *p,
1023                    char *buf)
1024{
1025    char arg_num_len_buf[12];
1026    const char __user *tmp_p = p;
1027    /* how many digits are in arg_num? 5 is the length of ' a=""' */
1028    size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5;
1029    size_t len, len_left, to_send;
1030    size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1031    unsigned int i, has_cntl = 0, too_long = 0;
1032    int ret;
1033
1034    /* strnlen_user includes the null we don't want to send */
1035    len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1036
1037    /*
1038     * We just created this mm, if we can't find the strings
1039     * we just copied into it something is _very_ wrong. Similar
1040     * for strings that are too long, we should not have created
1041     * any.
1042     */
1043    if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1044        WARN_ON(1);
1045        send_sig(SIGKILL, current, 0);
1046        return -1;
1047    }
1048
1049    /* walk the whole argument looking for non-ascii chars */
1050    do {
1051        if (len_left > MAX_EXECVE_AUDIT_LEN)
1052            to_send = MAX_EXECVE_AUDIT_LEN;
1053        else
1054            to_send = len_left;
1055        ret = copy_from_user(buf, tmp_p, to_send);
1056        /*
1057         * There is no reason for this copy to be short. We just
1058         * copied them here, and the mm hasn't been exposed to user-
1059         * space yet.
1060         */
1061        if (ret) {
1062            WARN_ON(1);
1063            send_sig(SIGKILL, current, 0);
1064            return -1;
1065        }
1066        buf[to_send] = '\0';
1067        has_cntl = audit_string_contains_control(buf, to_send);
1068        if (has_cntl) {
1069            /*
1070             * hex messages get logged as 2 bytes, so we can only
1071             * send half as much in each message
1072             */
1073            max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1074            break;
1075        }
1076        len_left -= to_send;
1077        tmp_p += to_send;
1078    } while (len_left > 0);
1079
1080    len_left = len;
1081
1082    if (len > max_execve_audit_len)
1083        too_long = 1;
1084
1085    /* rewalk the argument actually logging the message */
1086    for (i = 0; len_left > 0; i++) {
1087        int room_left;
1088
1089        if (len_left > max_execve_audit_len)
1090            to_send = max_execve_audit_len;
1091        else
1092            to_send = len_left;
1093
1094        /* do we have space left to send this argument in this ab? */
1095        room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1096        if (has_cntl)
1097            room_left -= (to_send * 2);
1098        else
1099            room_left -= to_send;
1100        if (room_left < 0) {
1101            *len_sent = 0;
1102            audit_log_end(*ab);
1103            *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1104            if (!*ab)
1105                return 0;
1106        }
1107
1108        /*
1109         * first record needs to say how long the original string was
1110         * so we can be sure nothing was lost.
1111         */
1112        if ((i == 0) && (too_long))
1113            audit_log_format(*ab, " a%d_len=%zu", arg_num,
1114                     has_cntl ? 2*len : len);
1115
1116        /*
1117         * normally arguments are small enough to fit and we already
1118         * filled buf above when we checked for control characters
1119         * so don't bother with another copy_from_user
1120         */
1121        if (len >= max_execve_audit_len)
1122            ret = copy_from_user(buf, p, to_send);
1123        else
1124            ret = 0;
1125        if (ret) {
1126            WARN_ON(1);
1127            send_sig(SIGKILL, current, 0);
1128            return -1;
1129        }
1130        buf[to_send] = '\0';
1131
1132        /* actually log it */
1133        audit_log_format(*ab, " a%d", arg_num);
1134        if (too_long)
1135            audit_log_format(*ab, "[%d]", i);
1136        audit_log_format(*ab, "=");
1137        if (has_cntl)
1138            audit_log_n_hex(*ab, buf, to_send);
1139        else
1140            audit_log_string(*ab, buf);
1141
1142        p += to_send;
1143        len_left -= to_send;
1144        *len_sent += arg_num_len;
1145        if (has_cntl)
1146            *len_sent += to_send * 2;
1147        else
1148            *len_sent += to_send;
1149    }
1150    /* include the null we didn't log */
1151    return len + 1;
1152}
1153
1154static void audit_log_execve_info(struct audit_context *context,
1155                  struct audit_buffer **ab,
1156                  struct audit_aux_data_execve *axi)
1157{
1158    int i;
1159    size_t len, len_sent = 0;
1160    const char __user *p;
1161    char *buf;
1162
1163    if (axi->mm != current->mm)
1164        return; /* execve failed, no additional info */
1165
1166    p = (const char __user *)axi->mm->arg_start;
1167
1168    audit_log_format(*ab, "argc=%d", axi->argc);
1169
1170    /*
1171     * we need some kernel buffer to hold the userspace args. Just
1172     * allocate one big one rather than allocating one of the right size
1173     * for every single argument inside audit_log_single_execve_arg()
1174     * should be <8k allocation so should be pretty safe.
1175     */
1176    buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1177    if (!buf) {
1178        audit_panic("out of memory for argv string\n");
1179        return;
1180    }
1181
1182    for (i = 0; i < axi->argc; i++) {
1183        len = audit_log_single_execve_arg(context, ab, i,
1184                          &len_sent, p, buf);
1185        if (len <= 0)
1186            break;
1187        p += len;
1188    }
1189    kfree(buf);
1190}
1191
1192static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
1193{
1194    int i;
1195
1196    audit_log_format(ab, " %s=", prefix);
1197    CAP_FOR_EACH_U32(i) {
1198        audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
1199    }
1200}
1201
1202static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1203{
1204    kernel_cap_t *perm = &name->fcap.permitted;
1205    kernel_cap_t *inh = &name->fcap.inheritable;
1206    int log = 0;
1207
1208    if (!cap_isclear(*perm)) {
1209        audit_log_cap(ab, "cap_fp", perm);
1210        log = 1;
1211    }
1212    if (!cap_isclear(*inh)) {
1213        audit_log_cap(ab, "cap_fi", inh);
1214        log = 1;
1215    }
1216
1217    if (log)
1218        audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver);
1219}
1220
1221static void show_special(struct audit_context *context, int *call_panic)
1222{
1223    struct audit_buffer *ab;
1224    int i;
1225
1226    ab = audit_log_start(context, GFP_KERNEL, context->type);
1227    if (!ab)
1228        return;
1229
1230    switch (context->type) {
1231    case AUDIT_SOCKETCALL: {
1232        int nargs = context->socketcall.nargs;
1233        audit_log_format(ab, "nargs=%d", nargs);
1234        for (i = 0; i < nargs; i++)
1235            audit_log_format(ab, " a%d=%lx", i,
1236                context->socketcall.args[i]);
1237        break; }
1238    case AUDIT_IPC: {
1239        u32 osid = context->ipc.osid;
1240
1241        audit_log_format(ab, "ouid=%u ogid=%u mode=%#o",
1242             context->ipc.uid, context->ipc.gid, context->ipc.mode);
1243        if (osid) {
1244            char *ctx = NULL;
1245            u32 len;
1246            if (security_secid_to_secctx(osid, &ctx, &len)) {
1247                audit_log_format(ab, " osid=%u", osid);
1248                *call_panic = 1;
1249            } else {
1250                audit_log_format(ab, " obj=%s", ctx);
1251                security_release_secctx(ctx, len);
1252            }
1253        }
1254        if (context->ipc.has_perm) {
1255            audit_log_end(ab);
1256            ab = audit_log_start(context, GFP_KERNEL,
1257                         AUDIT_IPC_SET_PERM);
1258            audit_log_format(ab,
1259                "qbytes=%lx ouid=%u ogid=%u mode=%#o",
1260                context->ipc.qbytes,
1261                context->ipc.perm_uid,
1262                context->ipc.perm_gid,
1263                context->ipc.perm_mode);
1264            if (!ab)
1265                return;
1266        }
1267        break; }
1268    case AUDIT_MQ_OPEN: {
1269        audit_log_format(ab,
1270            "oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
1271            "mq_msgsize=%ld mq_curmsgs=%ld",
1272            context->mq_open.oflag, context->mq_open.mode,
1273            context->mq_open.attr.mq_flags,
1274            context->mq_open.attr.mq_maxmsg,
1275            context->mq_open.attr.mq_msgsize,
1276            context->mq_open.attr.mq_curmsgs);
1277        break; }
1278    case AUDIT_MQ_SENDRECV: {
1279        audit_log_format(ab,
1280            "mqdes=%d msg_len=%zd msg_prio=%u "
1281            "abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1282            context->mq_sendrecv.mqdes,
1283            context->mq_sendrecv.msg_len,
1284            context->mq_sendrecv.msg_prio,
1285            context->mq_sendrecv.abs_timeout.tv_sec,
1286            context->mq_sendrecv.abs_timeout.tv_nsec);
1287        break; }
1288    case AUDIT_MQ_NOTIFY: {
1289        audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1290                context->mq_notify.mqdes,
1291                context->mq_notify.sigev_signo);
1292        break; }
1293    case AUDIT_MQ_GETSETATTR: {
1294        struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1295        audit_log_format(ab,
1296            "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1297            "mq_curmsgs=%ld ",
1298            context->mq_getsetattr.mqdes,
1299            attr->mq_flags, attr->mq_maxmsg,
1300            attr->mq_msgsize, attr->mq_curmsgs);
1301        break; }
1302    case AUDIT_CAPSET: {
1303        audit_log_format(ab, "pid=%d", context->capset.pid);
1304        audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1305        audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1306        audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1307        break; }
1308    }
1309    audit_log_end(ab);
1310}
1311
1312static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1313{
1314    const struct cred *cred;
1315    int i, call_panic = 0;
1316    struct audit_buffer *ab;
1317    struct audit_aux_data *aux;
1318    const char *tty;
1319
1320    /* tsk == current */
1321    context->pid = tsk->pid;
1322    if (!context->ppid)
1323        context->ppid = sys_getppid();
1324    cred = current_cred();
1325    context->uid = cred->uid;
1326    context->gid = cred->gid;
1327    context->euid = cred->euid;
1328    context->suid = cred->suid;
1329    context->fsuid = cred->fsuid;
1330    context->egid = cred->egid;
1331    context->sgid = cred->sgid;
1332    context->fsgid = cred->fsgid;
1333    context->personality = tsk->personality;
1334
1335    ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1336    if (!ab)
1337        return; /* audit_panic has been called */
1338    audit_log_format(ab, "arch=%x syscall=%d",
1339             context->arch, context->major);
1340    if (context->personality != PER_LINUX)
1341        audit_log_format(ab, " per=%lx", context->personality);
1342    if (context->return_valid)
1343        audit_log_format(ab, " success=%s exit=%ld",
1344                 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1345                 context->return_code);
1346
1347    spin_lock_irq(&tsk->sighand->siglock);
1348    if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1349        tty = tsk->signal->tty->name;
1350    else
1351        tty = "(none)";
1352    spin_unlock_irq(&tsk->sighand->siglock);
1353
1354    audit_log_format(ab,
1355          " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
1356          " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1357          " euid=%u suid=%u fsuid=%u"
1358          " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1359          context->argv[0],
1360          context->argv[1],
1361          context->argv[2],
1362          context->argv[3],
1363          context->name_count,
1364          context->ppid,
1365          context->pid,
1366          tsk->loginuid,
1367          context->uid,
1368          context->gid,
1369          context->euid, context->suid, context->fsuid,
1370          context->egid, context->sgid, context->fsgid, tty,
1371          tsk->sessionid);
1372
1373
1374    audit_log_task_info(ab, tsk);
1375    audit_log_key(ab, context->filterkey);
1376    audit_log_end(ab);
1377
1378    for (aux = context->aux; aux; aux = aux->next) {
1379
1380        ab = audit_log_start(context, GFP_KERNEL, aux->type);
1381        if (!ab)
1382            continue; /* audit_panic has been called */
1383
1384        switch (aux->type) {
1385
1386        case AUDIT_EXECVE: {
1387            struct audit_aux_data_execve *axi = (void *)aux;
1388            audit_log_execve_info(context, &ab, axi);
1389            break; }
1390
1391        case AUDIT_BPRM_FCAPS: {
1392            struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1393            audit_log_format(ab, "fver=%x", axs->fcap_ver);
1394            audit_log_cap(ab, "fp", &axs->fcap.permitted);
1395            audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1396            audit_log_format(ab, " fe=%d", axs->fcap.fE);
1397            audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1398            audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1399            audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1400            audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
1401            audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
1402            audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
1403            break; }
1404
1405        }
1406        audit_log_end(ab);
1407    }
1408
1409    if (context->type)
1410        show_special(context, &call_panic);
1411
1412    if (context->fds[0] >= 0) {
1413        ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1414        if (ab) {
1415            audit_log_format(ab, "fd0=%d fd1=%d",
1416                    context->fds[0], context->fds[1]);
1417            audit_log_end(ab);
1418        }
1419    }
1420
1421    if (context->sockaddr_len) {
1422        ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1423        if (ab) {
1424            audit_log_format(ab, "saddr=");
1425            audit_log_n_hex(ab, (void *)context->sockaddr,
1426                    context->sockaddr_len);
1427            audit_log_end(ab);
1428        }
1429    }
1430
1431    for (aux = context->aux_pids; aux; aux = aux->next) {
1432        struct audit_aux_data_pids *axs = (void *)aux;
1433
1434        for (i = 0; i < axs->pid_count; i++)
1435            if (audit_log_pid_context(context, axs->target_pid[i],
1436                          axs->target_auid[i],
1437                          axs->target_uid[i],
1438                          axs->target_sessionid[i],
1439                          axs->target_sid[i],
1440                          axs->target_comm[i]))
1441                call_panic = 1;
1442    }
1443
1444    if (context->target_pid &&
1445        audit_log_pid_context(context, context->target_pid,
1446                  context->target_auid, context->target_uid,
1447                  context->target_sessionid,
1448                  context->target_sid, context->target_comm))
1449            call_panic = 1;
1450
1451    if (context->pwd.dentry && context->pwd.mnt) {
1452        ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1453        if (ab) {
1454            audit_log_d_path(ab, "cwd=", &context->pwd);
1455            audit_log_end(ab);
1456        }
1457    }
1458    for (i = 0; i < context->name_count; i++) {
1459        struct audit_names *n = &context->names[i];
1460
1461        ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1462        if (!ab)
1463            continue; /* audit_panic has been called */
1464
1465        audit_log_format(ab, "item=%d", i);
1466
1467        if (n->name) {
1468            switch(n->name_len) {
1469            case AUDIT_NAME_FULL:
1470                /* log the full path */
1471                audit_log_format(ab, " name=");
1472                audit_log_untrustedstring(ab, n->name);
1473                break;
1474            case 0:
1475                /* name was specified as a relative path and the
1476                 * directory component is the cwd */
1477                audit_log_d_path(ab, "name=", &context->pwd);
1478                break;
1479            default:
1480                /* log the name's directory component */
1481                audit_log_format(ab, " name=");
1482                audit_log_n_untrustedstring(ab, n->name,
1483                                n->name_len);
1484            }
1485        } else
1486            audit_log_format(ab, " name=(null)");
1487
1488        if (n->ino != (unsigned long)-1) {
1489            audit_log_format(ab, " inode=%lu"
1490                     " dev=%02x:%02x mode=%#o"
1491                     " ouid=%u ogid=%u rdev=%02x:%02x",
1492                     n->ino,
1493                     MAJOR(n->dev),
1494                     MINOR(n->dev),
1495                     n->mode,
1496                     n->uid,
1497                     n->gid,
1498                     MAJOR(n->rdev),
1499                     MINOR(n->rdev));
1500        }
1501        if (n->osid != 0) {
1502            char *ctx = NULL;
1503            u32 len;
1504            if (security_secid_to_secctx(
1505                n->osid, &ctx, &len)) {
1506                audit_log_format(ab, " osid=%u", n->osid);
1507                call_panic = 2;
1508            } else {
1509                audit_log_format(ab, " obj=%s", ctx);
1510                security_release_secctx(ctx, len);
1511            }
1512        }
1513
1514        audit_log_fcaps(ab, n);
1515
1516        audit_log_end(ab);
1517    }
1518
1519    /* Send end of event record to help user space know we are finished */
1520    ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1521    if (ab)
1522        audit_log_end(ab);
1523    if (call_panic)
1524        audit_panic("error converting sid to string");
1525}
1526
1527/**
1528 * audit_free - free a per-task audit context
1529 * @tsk: task whose audit context block to free
1530 *
1531 * Called from copy_process and do_exit
1532 */
1533void audit_free(struct task_struct *tsk)
1534{
1535    struct audit_context *context;
1536
1537    context = audit_get_context(tsk, 0, 0);
1538    if (likely(!context))
1539        return;
1540
1541    /* Check for system calls that do not go through the exit
1542     * function (e.g., exit_group), then free context block.
1543     * We use GFP_ATOMIC here because we might be doing this
1544     * in the context of the idle thread */
1545    /* that can happen only if we are called from do_exit() */
1546    if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1547        audit_log_exit(context, tsk);
1548    if (!list_empty(&context->killed_trees))
1549        audit_kill_trees(&context->killed_trees);
1550
1551    audit_free_context(context);
1552}
1553
1554/**
1555 * audit_syscall_entry - fill in an audit record at syscall entry
1556 * @arch: architecture type
1557 * @major: major syscall type (function)
1558 * @a1: additional syscall register 1
1559 * @a2: additional syscall register 2
1560 * @a3: additional syscall register 3
1561 * @a4: additional syscall register 4
1562 *
1563 * Fill in audit context at syscall entry. This only happens if the
1564 * audit context was created when the task was created and the state or
1565 * filters demand the audit context be built. If the state from the
1566 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1567 * then the record will be written at syscall exit time (otherwise, it
1568 * will only be written if another part of the kernel requests that it
1569 * be written).
1570 */
1571void audit_syscall_entry(int arch, int major,
1572             unsigned long a1, unsigned long a2,
1573             unsigned long a3, unsigned long a4)
1574{
1575    struct task_struct *tsk = current;
1576    struct audit_context *context = tsk->audit_context;
1577    enum audit_state state;
1578
1579    if (unlikely(!context))
1580        return;
1581
1582    /*
1583     * This happens only on certain architectures that make system
1584     * calls in kernel_thread via the entry.S interface, instead of
1585     * with direct calls. (If you are porting to a new
1586     * architecture, hitting this condition can indicate that you
1587     * got the _exit/_leave calls backward in entry.S.)
1588     *
1589     * i386 no
1590     * x86_64 no
1591     * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S)
1592     *
1593     * This also happens with vm86 emulation in a non-nested manner
1594     * (entries without exits), so this case must be caught.
1595     */
1596    if (context->in_syscall) {
1597        struct audit_context *newctx;
1598
1599#if AUDIT_DEBUG
1600        printk(KERN_ERR
1601               "audit(:%d) pid=%d in syscall=%d;"
1602               " entering syscall=%d\n",
1603               context->serial, tsk->pid, context->major, major);
1604#endif
1605        newctx = audit_alloc_context(context->state);
1606        if (newctx) {
1607            newctx->previous = context;
1608            context = newctx;
1609            tsk->audit_context = newctx;
1610        } else {
1611            /* If we can't alloc a new context, the best we
1612             * can do is to leak memory (any pending putname
1613             * will be lost). The only other alternative is
1614             * to abandon auditing. */
1615            audit_zero_context(context, context->state);
1616        }
1617    }
1618    BUG_ON(context->in_syscall || context->name_count);
1619
1620    if (!audit_enabled)
1621        return;
1622
1623    context->arch = arch;
1624    context->major = major;
1625    context->argv[0] = a1;
1626    context->argv[1] = a2;
1627    context->argv[2] = a3;
1628    context->argv[3] = a4;
1629
1630    state = context->state;
1631    context->dummy = !audit_n_rules;
1632    if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
1633        context->prio = 0;
1634        state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1635    }
1636    if (likely(state == AUDIT_DISABLED))
1637        return;
1638
1639    context->serial = 0;
1640    context->ctime = CURRENT_TIME;
1641    context->in_syscall = 1;
1642    context->current_state = state;
1643    context->ppid = 0;
1644}
1645
1646void audit_finish_fork(struct task_struct *child)
1647{
1648    struct audit_context *ctx = current->audit_context;
1649    struct audit_context *p = child->audit_context;
1650    if (!p || !ctx)
1651        return;
1652    if (!ctx->in_syscall || ctx->current_state != AUDIT_RECORD_CONTEXT)
1653        return;
1654    p->arch = ctx->arch;
1655    p->major = ctx->major;
1656    memcpy(p->argv, ctx->argv, sizeof(ctx->argv));
1657    p->ctime = ctx->ctime;
1658    p->dummy = ctx->dummy;
1659    p->in_syscall = ctx->in_syscall;
1660    p->filterkey = kstrdup(ctx->filterkey, GFP_KERNEL);
1661    p->ppid = current->pid;
1662    p->prio = ctx->prio;
1663    p->current_state = ctx->current_state;
1664}
1665
1666/**
1667 * audit_syscall_exit - deallocate audit context after a system call
1668 * @valid: success/failure flag
1669 * @return_code: syscall return value
1670 *
1671 * Tear down after system call. If the audit context has been marked as
1672 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1673 * filtering, or because some other part of the kernel write an audit
1674 * message), then write out the syscall information. In call cases,
1675 * free the names stored from getname().
1676 */
1677void audit_syscall_exit(int valid, long return_code)
1678{
1679    struct task_struct *tsk = current;
1680    struct audit_context *context;
1681
1682    context = audit_get_context(tsk, valid, return_code);
1683
1684    if (likely(!context))
1685        return;
1686
1687    if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1688        audit_log_exit(context, tsk);
1689
1690    context->in_syscall = 0;
1691    context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1692
1693    if (!list_empty(&context->killed_trees))
1694        audit_kill_trees(&context->killed_trees);
1695
1696    if (context->previous) {
1697        struct audit_context *new_context = context->previous;
1698        context->previous = NULL;
1699        audit_free_context(context);
1700        tsk->audit_context = new_context;
1701    } else {
1702        audit_free_names(context);
1703        unroll_tree_refs(context, NULL, 0);
1704        audit_free_aux(context);
1705        context->aux = NULL;
1706        context->aux_pids = NULL;
1707        context->target_pid = 0;
1708        context->target_sid = 0;
1709        context->sockaddr_len = 0;
1710        context->type = 0;
1711        context->fds[0] = -1;
1712        if (context->state != AUDIT_RECORD_CONTEXT) {
1713            kfree(context->filterkey);
1714            context->filterkey = NULL;
1715        }
1716        tsk->audit_context = context;
1717    }
1718}
1719
1720static inline void handle_one(const struct inode *inode)
1721{
1722#ifdef CONFIG_AUDIT_TREE
1723    struct audit_context *context;
1724    struct audit_tree_refs *p;
1725    struct audit_chunk *chunk;
1726    int count;
1727    if (likely(hlist_empty(&inode->i_fsnotify_marks)))
1728        return;
1729    context = current->audit_context;
1730    p = context->trees;
1731    count = context->tree_count;
1732    rcu_read_lock();
1733    chunk = audit_tree_lookup(inode);
1734    rcu_read_unlock();
1735    if (!chunk)
1736        return;
1737    if (likely(put_tree_ref(context, chunk)))
1738        return;
1739    if (unlikely(!grow_tree_refs(context))) {
1740        printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
1741        audit_set_auditable(context);
1742        audit_put_chunk(chunk);
1743        unroll_tree_refs(context, p, count);
1744        return;
1745    }
1746    put_tree_ref(context, chunk);
1747#endif
1748}
1749
1750static void handle_path(const struct dentry *dentry)
1751{
1752#ifdef CONFIG_AUDIT_TREE
1753    struct audit_context *context;
1754    struct audit_tree_refs *p;
1755    const struct dentry *d, *parent;
1756    struct audit_chunk *drop;
1757    unsigned long seq;
1758    int count;
1759
1760    context = current->audit_context;
1761    p = context->trees;
1762    count = context->tree_count;
1763retry:
1764    drop = NULL;
1765    d = dentry;
1766    rcu_read_lock();
1767    seq = read_seqbegin(&rename_lock);
1768    for(;;) {
1769        struct inode *inode = d->d_inode;
1770        if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
1771            struct audit_chunk *chunk;
1772            chunk = audit_tree_lookup(inode);
1773            if (chunk) {
1774                if (unlikely(!put_tree_ref(context, chunk))) {
1775                    drop = chunk;
1776                    break;
1777                }
1778            }
1779        }
1780        parent = d->d_parent;
1781        if (parent == d)
1782            break;
1783        d = parent;
1784    }
1785    if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */
1786        rcu_read_unlock();
1787        if (!drop) {
1788            /* just a race with rename */
1789            unroll_tree_refs(context, p, count);
1790            goto retry;
1791        }
1792        audit_put_chunk(drop);
1793        if (grow_tree_refs(context)) {
1794            /* OK, got more space */
1795            unroll_tree_refs(context, p, count);
1796            goto retry;
1797        }
1798        /* too bad */
1799        printk(KERN_WARNING
1800            "out of memory, audit has lost a tree reference\n");
1801        unroll_tree_refs(context, p, count);
1802        audit_set_auditable(context);
1803        return;
1804    }
1805    rcu_read_unlock();
1806#endif
1807}
1808
1809/**
1810 * audit_getname - add a name to the list
1811 * @name: name to add
1812 *
1813 * Add a name to the list of audit names for this context.
1814 * Called from fs/namei.c:getname().
1815 */
1816void __audit_getname(const char *name)
1817{
1818    struct audit_context *context = current->audit_context;
1819
1820    if (IS_ERR(name) || !name)
1821        return;
1822
1823    if (!context->in_syscall) {
1824#if AUDIT_DEBUG == 2
1825        printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1826               __FILE__, __LINE__, context->serial, name);
1827        dump_stack();
1828#endif
1829        return;
1830    }
1831    BUG_ON(context->name_count >= AUDIT_NAMES);
1832    context->names[context->name_count].name = name;
1833    context->names[context->name_count].name_len = AUDIT_NAME_FULL;
1834    context->names[context->name_count].name_put = 1;
1835    context->names[context->name_count].ino = (unsigned long)-1;
1836    context->names[context->name_count].osid = 0;
1837    ++context->name_count;
1838    if (!context->pwd.dentry)
1839        get_fs_pwd(current->fs, &context->pwd);
1840}
1841
1842/* audit_putname - intercept a putname request
1843 * @name: name to intercept and delay for putname
1844 *
1845 * If we have stored the name from getname in the audit context,
1846 * then we delay the putname until syscall exit.
1847 * Called from include/linux/fs.h:putname().
1848 */
1849void audit_putname(const char *name)
1850{
1851    struct audit_context *context = current->audit_context;
1852
1853    BUG_ON(!context);
1854    if (!context->in_syscall) {
1855#if AUDIT_DEBUG == 2
1856        printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
1857               __FILE__, __LINE__, context->serial, name);
1858        if (context->name_count) {
1859            int i;
1860            for (i = 0; i < context->name_count; i++)
1861                printk(KERN_ERR "name[%d] = %p = %s\n", i,
1862                       context->names[i].name,
1863                       context->names[i].name ?: "(null)");
1864        }
1865#endif
1866        __putname(name);
1867    }
1868#if AUDIT_DEBUG
1869    else {
1870        ++context->put_count;
1871        if (context->put_count > context->name_count) {
1872            printk(KERN_ERR "%s:%d(:%d): major=%d"
1873                   " in_syscall=%d putname(%p) name_count=%d"
1874                   " put_count=%d\n",
1875                   __FILE__, __LINE__,
1876                   context->serial, context->major,
1877                   context->in_syscall, name, context->name_count,
1878                   context->put_count);
1879            dump_stack();
1880        }
1881    }
1882#endif
1883}
1884
1885static int audit_inc_name_count(struct audit_context *context,
1886                const struct inode *inode)
1887{
1888    if (context->name_count >= AUDIT_NAMES) {
1889        if (inode)
1890            printk(KERN_DEBUG "audit: name_count maxed, losing inode data: "
1891                   "dev=%02x:%02x, inode=%lu\n",
1892                   MAJOR(inode->i_sb->s_dev),
1893                   MINOR(inode->i_sb->s_dev),
1894                   inode->i_ino);
1895
1896        else
1897            printk(KERN_DEBUG "name_count maxed, losing inode data\n");
1898        return 1;
1899    }
1900    context->name_count++;
1901#if AUDIT_DEBUG
1902    context->ino_count++;
1903#endif
1904    return 0;
1905}
1906
1907
1908static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry)
1909{
1910    struct cpu_vfs_cap_data caps;
1911    int rc;
1912
1913    memset(&name->fcap.permitted, 0, sizeof(kernel_cap_t));
1914    memset(&name->fcap.inheritable, 0, sizeof(kernel_cap_t));
1915    name->fcap.fE = 0;
1916    name->fcap_ver = 0;
1917
1918    if (!dentry)
1919        return 0;
1920
1921    rc = get_vfs_caps_from_disk(dentry, &caps);
1922    if (rc)
1923        return rc;
1924
1925    name->fcap.permitted = caps.permitted;
1926    name->fcap.inheritable = caps.inheritable;
1927    name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
1928    name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
1929
1930    return 0;
1931}
1932
1933
1934/* Copy inode data into an audit_names. */
1935static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
1936                 const struct inode *inode)
1937{
1938    name->ino = inode->i_ino;
1939    name->dev = inode->i_sb->s_dev;
1940    name->mode = inode->i_mode;
1941    name->uid = inode->i_uid;
1942    name->gid = inode->i_gid;
1943    name->rdev = inode->i_rdev;
1944    security_inode_getsecid(inode, &name->osid);
1945    audit_copy_fcaps(name, dentry);
1946}
1947
1948/**
1949 * audit_inode - store the inode and device from a lookup
1950 * @name: name being audited
1951 * @dentry: dentry being audited
1952 *
1953 * Called from fs/namei.c:path_lookup().
1954 */
1955void __audit_inode(const char *name, const struct dentry *dentry)
1956{
1957    int idx;
1958    struct audit_context *context = current->audit_context;
1959    const struct inode *inode = dentry->d_inode;
1960
1961    if (!context->in_syscall)
1962        return;
1963    if (context->name_count
1964        && context->names[context->name_count-1].name
1965        && context->names[context->name_count-1].name == name)
1966        idx = context->name_count - 1;
1967    else if (context->name_count > 1
1968         && context->names[context->name_count-2].name
1969         && context->names[context->name_count-2].name == name)
1970        idx = context->name_count - 2;
1971    else {
1972        /* FIXME: how much do we care about inodes that have no
1973         * associated name? */
1974        if (audit_inc_name_count(context, inode))
1975            return;
1976        idx = context->name_count - 1;
1977        context->names[idx].name = NULL;
1978    }
1979    handle_path(dentry);
1980    audit_copy_inode(&context->names[idx], dentry, inode);
1981}
1982
1983/**
1984 * audit_inode_child - collect inode info for created/removed objects
1985 * @dentry: dentry being audited
1986 * @parent: inode of dentry parent
1987 *
1988 * For syscalls that create or remove filesystem objects, audit_inode
1989 * can only collect information for the filesystem object's parent.
1990 * This call updates the audit context with the child's information.
1991 * Syscalls that create a new filesystem object must be hooked after
1992 * the object is created. Syscalls that remove a filesystem object
1993 * must be hooked prior, in order to capture the target inode during
1994 * unsuccessful attempts.
1995 */
1996void __audit_inode_child(const struct dentry *dentry,
1997             const struct inode *parent)
1998{
1999    int idx;
2000    struct audit_context *context = current->audit_context;
2001    const char *found_parent = NULL, *found_child = NULL;
2002    const struct inode *inode = dentry->d_inode;
2003    const char *dname = dentry->d_name.name;
2004    int dirlen = 0;
2005
2006    if (!context->in_syscall)
2007        return;
2008
2009    if (inode)
2010        handle_one(inode);
2011
2012    /* parent is more likely, look for it first */
2013    for (idx = 0; idx < context->name_count; idx++) {
2014        struct audit_names *n = &context->names[idx];
2015
2016        if (!n->name)
2017            continue;
2018
2019        if (n->ino == parent->i_ino &&
2020            !audit_compare_dname_path(dname, n->name, &dirlen)) {
2021            n->name_len = dirlen; /* update parent data in place */
2022            found_parent = n->name;
2023            goto add_names;
2024        }
2025    }
2026
2027    /* no matching parent, look for matching child */
2028    for (idx = 0; idx < context->name_count; idx++) {
2029        struct audit_names *n = &context->names[idx];
2030
2031        if (!n->name)
2032            continue;
2033
2034        /* strcmp() is the more likely scenario */
2035        if (!strcmp(dname, n->name) ||
2036             !audit_compare_dname_path(dname, n->name, &dirlen)) {
2037            if (inode)
2038                audit_copy_inode(n, NULL, inode);
2039            else
2040                n->ino = (unsigned long)-1;
2041            found_child = n->name;
2042            goto add_names;
2043        }
2044    }
2045
2046add_names:
2047    if (!found_parent) {
2048        if (audit_inc_name_count(context, parent))
2049            return;
2050        idx = context->name_count - 1;
2051        context->names[idx].name = NULL;
2052        audit_copy_inode(&context->names[idx], NULL, parent);
2053    }
2054
2055    if (!found_child) {
2056        if (audit_inc_name_count(context, inode))
2057            return;
2058        idx = context->name_count - 1;
2059
2060        /* Re-use the name belonging to the slot for a matching parent
2061         * directory. All names for this context are relinquished in
2062         * audit_free_names() */
2063        if (found_parent) {
2064            context->names[idx].name = found_parent;
2065            context->names[idx].name_len = AUDIT_NAME_FULL;
2066            /* don't call __putname() */
2067            context->names[idx].name_put = 0;
2068        } else {
2069            context->names[idx].name = NULL;
2070        }
2071
2072        if (inode)
2073            audit_copy_inode(&context->names[idx], NULL, inode);
2074        else
2075            context->names[idx].ino = (unsigned long)-1;
2076    }
2077}
2078EXPORT_SYMBOL_GPL(__audit_inode_child);
2079
2080/**
2081 * auditsc_get_stamp - get local copies of audit_context values
2082 * @ctx: audit_context for the task
2083 * @t: timespec to store time recorded in the audit_context
2084 * @serial: serial value that is recorded in the audit_context
2085 *
2086 * Also sets the context as auditable.
2087 */
2088int auditsc_get_stamp(struct audit_context *ctx,
2089               struct timespec *t, unsigned int *serial)
2090{
2091    if (!ctx->in_syscall)
2092        return 0;
2093    if (!ctx->serial)
2094        ctx->serial = audit_serial();
2095    t->tv_sec = ctx->ctime.tv_sec;
2096    t->tv_nsec = ctx->ctime.tv_nsec;
2097    *serial = ctx->serial;
2098    if (!ctx->prio) {
2099        ctx->prio = 1;
2100        ctx->current_state = AUDIT_RECORD_CONTEXT;
2101    }
2102    return 1;
2103}
2104
2105/* global counter which is incremented every time something logs in */
2106static atomic_t session_id = ATOMIC_INIT(0);
2107
2108/**
2109 * audit_set_loginuid - set a task's audit_context loginuid
2110 * @task: task whose audit context is being modified
2111 * @loginuid: loginuid value
2112 *
2113 * Returns 0.
2114 *
2115 * Called (set) from fs/proc/base.c::proc_loginuid_write().
2116 */
2117int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
2118{
2119    unsigned int sessionid = atomic_inc_return(&session_id);
2120    struct audit_context *context = task->audit_context;
2121
2122    if (context && context->in_syscall) {
2123        struct audit_buffer *ab;
2124
2125        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
2126        if (ab) {
2127            audit_log_format(ab, "login pid=%d uid=%u "
2128                "old auid=%u new auid=%u"
2129                " old ses=%u new ses=%u",
2130                task->pid, task_uid(task),
2131                task->loginuid, loginuid,
2132                task->sessionid, sessionid);
2133            audit_log_end(ab);
2134        }
2135    }
2136    task->sessionid = sessionid;
2137    task->loginuid = loginuid;
2138    return 0;
2139}
2140
2141/**
2142 * __audit_mq_open - record audit data for a POSIX MQ open
2143 * @oflag: open flag
2144 * @mode: mode bits
2145 * @attr: queue attributes
2146 *
2147 */
2148void __audit_mq_open(int oflag, mode_t mode, struct mq_attr *attr)
2149{
2150    struct audit_context *context = current->audit_context;
2151
2152    if (attr)
2153        memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2154    else
2155        memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2156
2157    context->mq_open.oflag = oflag;
2158    context->mq_open.mode = mode;
2159
2160    context->type = AUDIT_MQ_OPEN;
2161}
2162
2163/**
2164 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2165 * @mqdes: MQ descriptor
2166 * @msg_len: Message length
2167 * @msg_prio: Message priority
2168 * @abs_timeout: Message timeout in absolute time
2169 *
2170 */
2171void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2172            const struct timespec *abs_timeout)
2173{
2174    struct audit_context *context = current->audit_context;
2175    struct timespec *p = &context->mq_sendrecv.abs_timeout;
2176
2177    if (abs_timeout)
2178        memcpy(p, abs_timeout, sizeof(struct timespec));
2179    else
2180        memset(p, 0, sizeof(struct timespec));
2181
2182    context->mq_sendrecv.mqdes = mqdes;
2183    context->mq_sendrecv.msg_len = msg_len;
2184    context->mq_sendrecv.msg_prio = msg_prio;
2185
2186    context->type = AUDIT_MQ_SENDRECV;
2187}
2188
2189/**
2190 * __audit_mq_notify - record audit data for a POSIX MQ notify
2191 * @mqdes: MQ descriptor
2192 * @notification: Notification event
2193 *
2194 */
2195
2196void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2197{
2198    struct audit_context *context = current->audit_context;
2199
2200    if (notification)
2201        context->mq_notify.sigev_signo = notification->sigev_signo;
2202    else
2203        context->mq_notify.sigev_signo = 0;
2204
2205    context->mq_notify.mqdes = mqdes;
2206    context->type = AUDIT_MQ_NOTIFY;
2207}
2208
2209/**
2210 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2211 * @mqdes: MQ descriptor
2212 * @mqstat: MQ flags
2213 *
2214 */
2215void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2216{
2217    struct audit_context *context = current->audit_context;
2218    context->mq_getsetattr.mqdes = mqdes;
2219    context->mq_getsetattr.mqstat = *mqstat;
2220    context->type = AUDIT_MQ_GETSETATTR;
2221}
2222
2223/**
2224 * audit_ipc_obj - record audit data for ipc object
2225 * @ipcp: ipc permissions
2226 *
2227 */
2228void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2229{
2230    struct audit_context *context = current->audit_context;
2231    context->ipc.uid = ipcp->uid;
2232    context->ipc.gid = ipcp->gid;
2233    context->ipc.mode = ipcp->mode;
2234    context->ipc.has_perm = 0;
2235    security_ipc_getsecid(ipcp, &context->ipc.osid);
2236    context->type = AUDIT_IPC;
2237}
2238
2239/**
2240 * audit_ipc_set_perm - record audit data for new ipc permissions
2241 * @qbytes: msgq bytes
2242 * @uid: msgq user id
2243 * @gid: msgq group id
2244 * @mode: msgq mode (permissions)
2245 *
2246 * Called only after audit_ipc_obj().
2247 */
2248void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
2249{
2250    struct audit_context *context = current->audit_context;
2251
2252    context->ipc.qbytes = qbytes;
2253    context->ipc.perm_uid = uid;
2254    context->ipc.perm_gid = gid;
2255    context->ipc.perm_mode = mode;
2256    context->ipc.has_perm = 1;
2257}
2258
2259int audit_bprm(struct linux_binprm *bprm)
2260{
2261    struct audit_aux_data_execve *ax;
2262    struct audit_context *context = current->audit_context;
2263
2264    if (likely(!audit_enabled || !context || context->dummy))
2265        return 0;
2266
2267    ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2268    if (!ax)
2269        return -ENOMEM;
2270
2271    ax->argc = bprm->argc;
2272    ax->envc = bprm->envc;
2273    ax->mm = bprm->mm;
2274    ax->d.type = AUDIT_EXECVE;
2275    ax->d.next = context->aux;
2276    context->aux = (void *)ax;
2277    return 0;
2278}
2279
2280
2281/**
2282 * audit_socketcall - record audit data for sys_socketcall
2283 * @nargs: number of args
2284 * @args: args array
2285 *
2286 */
2287void audit_socketcall(int nargs, unsigned long *args)
2288{
2289    struct audit_context *context = current->audit_context;
2290
2291    if (likely(!context || context->dummy))
2292        return;
2293
2294    context->type = AUDIT_SOCKETCALL;
2295    context->socketcall.nargs = nargs;
2296    memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2297}
2298
2299/**
2300 * __audit_fd_pair - record audit data for pipe and socketpair
2301 * @fd1: the first file descriptor
2302 * @fd2: the second file descriptor
2303 *
2304 */
2305void __audit_fd_pair(int fd1, int fd2)
2306{
2307    struct audit_context *context = current->audit_context;
2308    context->fds[0] = fd1;
2309    context->fds[1] = fd2;
2310}
2311
2312/**
2313 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2314 * @len: data length in user space
2315 * @a: data address in kernel space
2316 *
2317 * Returns 0 for success or NULL context or < 0 on error.
2318 */
2319int audit_sockaddr(int len, void *a)
2320{
2321    struct audit_context *context = current->audit_context;
2322
2323    if (likely(!context || context->dummy))
2324        return 0;
2325
2326    if (!context->sockaddr) {
2327        void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2328        if (!p)
2329            return -ENOMEM;
2330        context->sockaddr = p;
2331    }
2332
2333    context->sockaddr_len = len;
2334    memcpy(context->sockaddr, a, len);
2335    return 0;
2336}
2337
2338void __audit_ptrace(struct task_struct *t)
2339{
2340    struct audit_context *context = current->audit_context;
2341
2342    context->target_pid = t->pid;
2343    context->target_auid = audit_get_loginuid(t);
2344    context->target_uid = task_uid(t);
2345    context->target_sessionid = audit_get_sessionid(t);
2346    security_task_getsecid(t, &context->target_sid);
2347    memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2348}
2349
2350/**
2351 * audit_signal_info - record signal info for shutting down audit subsystem
2352 * @sig: signal value
2353 * @t: task being signaled
2354 *
2355 * If the audit subsystem is being terminated, record the task (pid)
2356 * and uid that is doing that.
2357 */
2358int __audit_signal_info(int sig, struct task_struct *t)
2359{
2360    struct audit_aux_data_pids *axp;
2361    struct task_struct *tsk = current;
2362    struct audit_context *ctx = tsk->audit_context;
2363    uid_t uid = current_uid(), t_uid = task_uid(t);
2364
2365    if (audit_pid && t->tgid == audit_pid) {
2366        if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
2367            audit_sig_pid = tsk->pid;
2368            if (tsk->loginuid != -1)
2369                audit_sig_uid = tsk->loginuid;
2370            else
2371                audit_sig_uid = uid;
2372            security_task_getsecid(tsk, &audit_sig_sid);
2373        }
2374        if (!audit_signals || audit_dummy_context())
2375            return 0;
2376    }
2377
2378    /* optimize the common case by putting first signal recipient directly
2379     * in audit_context */
2380    if (!ctx->target_pid) {
2381        ctx->target_pid = t->tgid;
2382        ctx->target_auid = audit_get_loginuid(t);
2383        ctx->target_uid = t_uid;
2384        ctx->target_sessionid = audit_get_sessionid(t);
2385        security_task_getsecid(t, &ctx->target_sid);
2386        memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2387        return 0;
2388    }
2389
2390    axp = (void *)ctx->aux_pids;
2391    if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2392        axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2393        if (!axp)
2394            return -ENOMEM;
2395
2396        axp->d.type = AUDIT_OBJ_PID;
2397        axp->d.next = ctx->aux_pids;
2398        ctx->aux_pids = (void *)axp;
2399    }
2400    BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2401
2402    axp->target_pid[axp->pid_count] = t->tgid;
2403    axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2404    axp->target_uid[axp->pid_count] = t_uid;
2405    axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2406    security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2407    memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2408    axp->pid_count++;
2409
2410    return 0;
2411}
2412
2413/**
2414 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2415 * @bprm: pointer to the bprm being processed
2416 * @new: the proposed new credentials
2417 * @old: the old credentials
2418 *
2419 * Simply check if the proc already has the caps given by the file and if not
2420 * store the priv escalation info for later auditing at the end of the syscall
2421 *
2422 * -Eric
2423 */
2424int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2425               const struct cred *new, const struct cred *old)
2426{
2427    struct audit_aux_data_bprm_fcaps *ax;
2428    struct audit_context *context = current->audit_context;
2429    struct cpu_vfs_cap_data vcaps;
2430    struct dentry *dentry;
2431
2432    ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2433    if (!ax)
2434        return -ENOMEM;
2435
2436    ax->d.type = AUDIT_BPRM_FCAPS;
2437    ax->d.next = context->aux;
2438    context->aux = (void *)ax;
2439
2440    dentry = dget(bprm->file->f_dentry);
2441    get_vfs_caps_from_disk(dentry, &vcaps);
2442    dput(dentry);
2443
2444    ax->fcap.permitted = vcaps.permitted;
2445    ax->fcap.inheritable = vcaps.inheritable;
2446    ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2447    ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2448
2449    ax->old_pcap.permitted = old->cap_permitted;
2450    ax->old_pcap.inheritable = old->cap_inheritable;
2451    ax->old_pcap.effective = old->cap_effective;
2452
2453    ax->new_pcap.permitted = new->cap_permitted;
2454    ax->new_pcap.inheritable = new->cap_inheritable;
2455    ax->new_pcap.effective = new->cap_effective;
2456    return 0;
2457}
2458
2459/**
2460 * __audit_log_capset - store information about the arguments to the capset syscall
2461 * @pid: target pid of the capset call
2462 * @new: the new credentials
2463 * @old: the old (current) credentials
2464 *
2465 * Record the aguments userspace sent to sys_capset for later printing by the
2466 * audit system if applicable
2467 */
2468void __audit_log_capset(pid_t pid,
2469               const struct cred *new, const struct cred *old)
2470{
2471    struct audit_context *context = current->audit_context;
2472    context->capset.pid = pid;
2473    context->capset.cap.effective = new->cap_effective;
2474    context->capset.cap.inheritable = new->cap_effective;
2475    context->capset.cap.permitted = new->cap_permitted;
2476    context->type = AUDIT_CAPSET;
2477}
2478
2479/**
2480 * audit_core_dumps - record information about processes that end abnormally
2481 * @signr: signal value
2482 *
2483 * If a process ends with a core dump, something fishy is going on and we
2484 * should record the event for investigation.
2485 */
2486void audit_core_dumps(long signr)
2487{
2488    struct audit_buffer *ab;
2489    u32 sid;
2490    uid_t auid = audit_get_loginuid(current), uid;
2491    gid_t gid;
2492    unsigned int sessionid = audit_get_sessionid(current);
2493
2494    if (!audit_enabled)
2495        return;
2496
2497    if (signr == SIGQUIT) /* don't care for those */
2498        return;
2499
2500    ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2501    current_uid_gid(&uid, &gid);
2502    audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2503             auid, uid, gid, sessionid);
2504    security_task_getsecid(current, &sid);
2505    if (sid) {
2506        char *ctx = NULL;
2507        u32 len;
2508
2509        if (security_secid_to_secctx(sid, &ctx, &len))
2510            audit_log_format(ab, " ssid=%u", sid);
2511        else {
2512            audit_log_format(ab, " subj=%s", ctx);
2513            security_release_secctx(ctx, len);
2514        }
2515    }
2516    audit_log_format(ab, " pid=%d comm=", current->pid);
2517    audit_log_untrustedstring(ab, current->comm);
2518    audit_log_format(ab, " sig=%ld", signr);
2519    audit_log_end(ab);
2520}
2521
2522struct list_head *audit_killed_trees(void)
2523{
2524    struct audit_context *ctx = current->audit_context;
2525    if (likely(!ctx || !ctx->in_syscall))
2526        return NULL;
2527    return &ctx->killed_trees;
2528}
2529

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