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 <linux/atomic.h>
48#include <linux/fs.h>
49#include <linux/namei.h>
50#include <linux/mm.h>
51#include <linux/export.h>
52#include <linux/slab.h>
53#include <linux/mount.h>
54#include <linux/socket.h>
55#include <linux/mqueue.h>
56#include <linux/audit.h>
57#include <linux/personality.h>
58#include <linux/time.h>
59#include <linux/netlink.h>
60#include <linux/compiler.h>
61#include <asm/unistd.h>
62#include <linux/security.h>
63#include <linux/list.h>
64#include <linux/tty.h>
65#include <linux/binfmts.h>
66#include <linux/highmem.h>
67#include <linux/syscalls.h>
68#include <linux/capability.h>
69#include <linux/fs_struct.h>
70#include <linux/compat.h>
71
72#include "audit.h"
73
74/* flags stating the success for a syscall */
75#define AUDITSC_INVALID 0
76#define AUDITSC_SUCCESS 1
77#define AUDITSC_FAILURE 2
78
79/* AUDIT_NAMES is the number of slots we reserve in the audit_context
80 * for saving names from getname(). If we get more names we will allocate
81 * a name dynamically and also add those to the list anchored by names_list. */
82#define AUDIT_NAMES 5
83
84/* Indicates that audit should log the full pathname. */
85#define AUDIT_NAME_FULL -1
86
87/* no execve audit message should be longer than this (userspace limits) */
88#define MAX_EXECVE_AUDIT_LEN 7500
89
90/* number of audit rules */
91int audit_n_rules;
92
93/* determines whether we collect data for signals sent */
94int audit_signals;
95
96struct audit_cap_data {
97    kernel_cap_t permitted;
98    kernel_cap_t inheritable;
99    union {
100        unsigned int fE; /* effective bit of a file capability */
101        kernel_cap_t effective; /* effective set of a process */
102    };
103};
104
105/* When fs/namei.c:getname() is called, we store the pointer in name and
106 * we don't let putname() free it (instead we free all of the saved
107 * pointers at syscall exit time).
108 *
109 * Further, in fs/namei.c:path_lookup() we store the inode and device. */
110struct audit_names {
111    struct list_head list; /* audit_context->names_list */
112    const char *name;
113    unsigned long ino;
114    dev_t dev;
115    umode_t mode;
116    uid_t uid;
117    gid_t gid;
118    dev_t rdev;
119    u32 osid;
120    struct audit_cap_data fcap;
121    unsigned int fcap_ver;
122    int name_len; /* number of name's characters to log */
123    bool name_put; /* call __putname() for this name */
124    /*
125     * This was an allocated audit_names and not from the array of
126     * names allocated in the task audit context. Thus this name
127     * should be freed on syscall exit
128     */
129    bool should_free;
130};
131
132struct audit_aux_data {
133    struct audit_aux_data *next;
134    int type;
135};
136
137#define AUDIT_AUX_IPCPERM 0
138
139/* Number of target pids per aux struct. */
140#define AUDIT_AUX_PIDS 16
141
142struct audit_aux_data_execve {
143    struct audit_aux_data d;
144    int argc;
145    int envc;
146    struct mm_struct *mm;
147};
148
149struct audit_aux_data_pids {
150    struct audit_aux_data d;
151    pid_t target_pid[AUDIT_AUX_PIDS];
152    uid_t target_auid[AUDIT_AUX_PIDS];
153    uid_t target_uid[AUDIT_AUX_PIDS];
154    unsigned int target_sessionid[AUDIT_AUX_PIDS];
155    u32 target_sid[AUDIT_AUX_PIDS];
156    char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
157    int pid_count;
158};
159
160struct audit_aux_data_bprm_fcaps {
161    struct audit_aux_data d;
162    struct audit_cap_data fcap;
163    unsigned int fcap_ver;
164    struct audit_cap_data old_pcap;
165    struct audit_cap_data new_pcap;
166};
167
168struct audit_aux_data_capset {
169    struct audit_aux_data d;
170    pid_t pid;
171    struct audit_cap_data cap;
172};
173
174struct audit_tree_refs {
175    struct audit_tree_refs *next;
176    struct audit_chunk *c[31];
177};
178
179/* The per-task audit context. */
180struct audit_context {
181    int dummy; /* must be the first element */
182    int in_syscall; /* 1 if task is in a syscall */
183    enum audit_state state, current_state;
184    unsigned int serial; /* serial number for record */
185    int major; /* syscall number */
186    struct timespec ctime; /* time of syscall entry */
187    unsigned long argv[4]; /* syscall arguments */
188    long return_code;/* syscall return code */
189    u64 prio;
190    int return_valid; /* return code is valid */
191    /*
192     * The names_list is the list of all audit_names collected during this
193     * syscall. The first AUDIT_NAMES entries in the names_list will
194     * actually be from the preallocated_names array for performance
195     * reasons. Except during allocation they should never be referenced
196     * through the preallocated_names array and should only be found/used
197     * by running the names_list.
198     */
199    struct audit_names preallocated_names[AUDIT_NAMES];
200    int name_count; /* total records in names_list */
201    struct list_head names_list; /* anchor for struct audit_names->list */
202    char * filterkey; /* key for rule that triggered record */
203    struct path pwd;
204    struct audit_context *previous; /* For nested syscalls */
205    struct audit_aux_data *aux;
206    struct audit_aux_data *aux_pids;
207    struct sockaddr_storage *sockaddr;
208    size_t sockaddr_len;
209                /* Save things to print about task_struct */
210    pid_t pid, ppid;
211    uid_t uid, euid, suid, fsuid;
212    gid_t gid, egid, sgid, fsgid;
213    unsigned long personality;
214    int arch;
215
216    pid_t target_pid;
217    uid_t target_auid;
218    uid_t target_uid;
219    unsigned int target_sessionid;
220    u32 target_sid;
221    char target_comm[TASK_COMM_LEN];
222
223    struct audit_tree_refs *trees, *first_trees;
224    struct list_head killed_trees;
225    int tree_count;
226
227    int type;
228    union {
229        struct {
230            int nargs;
231            long args[6];
232        } socketcall;
233        struct {
234            uid_t uid;
235            gid_t gid;
236            umode_t mode;
237            u32 osid;
238            int has_perm;
239            uid_t perm_uid;
240            gid_t perm_gid;
241            umode_t perm_mode;
242            unsigned long qbytes;
243        } ipc;
244        struct {
245            mqd_t mqdes;
246            struct mq_attr mqstat;
247        } mq_getsetattr;
248        struct {
249            mqd_t mqdes;
250            int sigev_signo;
251        } mq_notify;
252        struct {
253            mqd_t mqdes;
254            size_t msg_len;
255            unsigned int msg_prio;
256            struct timespec abs_timeout;
257        } mq_sendrecv;
258        struct {
259            int oflag;
260            umode_t mode;
261            struct mq_attr attr;
262        } mq_open;
263        struct {
264            pid_t pid;
265            struct audit_cap_data cap;
266        } capset;
267        struct {
268            int fd;
269            int flags;
270        } mmap;
271    };
272    int fds[2];
273
274#if AUDIT_DEBUG
275    int put_count;
276    int ino_count;
277#endif
278};
279
280static inline int open_arg(int flags, int mask)
281{
282    int n = ACC_MODE(flags);
283    if (flags & (O_TRUNC | O_CREAT))
284        n |= AUDIT_PERM_WRITE;
285    return n & mask;
286}
287
288static int audit_match_perm(struct audit_context *ctx, int mask)
289{
290    unsigned n;
291    if (unlikely(!ctx))
292        return 0;
293    n = ctx->major;
294
295    switch (audit_classify_syscall(ctx->arch, n)) {
296    case 0: /* native */
297        if ((mask & AUDIT_PERM_WRITE) &&
298             audit_match_class(AUDIT_CLASS_WRITE, n))
299            return 1;
300        if ((mask & AUDIT_PERM_READ) &&
301             audit_match_class(AUDIT_CLASS_READ, n))
302            return 1;
303        if ((mask & AUDIT_PERM_ATTR) &&
304             audit_match_class(AUDIT_CLASS_CHATTR, n))
305            return 1;
306        return 0;
307    case 1: /* 32bit on biarch */
308        if ((mask & AUDIT_PERM_WRITE) &&
309             audit_match_class(AUDIT_CLASS_WRITE_32, n))
310            return 1;
311        if ((mask & AUDIT_PERM_READ) &&
312             audit_match_class(AUDIT_CLASS_READ_32, n))
313            return 1;
314        if ((mask & AUDIT_PERM_ATTR) &&
315             audit_match_class(AUDIT_CLASS_CHATTR_32, n))
316            return 1;
317        return 0;
318    case 2: /* open */
319        return mask & ACC_MODE(ctx->argv[1]);
320    case 3: /* openat */
321        return mask & ACC_MODE(ctx->argv[2]);
322    case 4: /* socketcall */
323        return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
324    case 5: /* execve */
325        return mask & AUDIT_PERM_EXEC;
326    default:
327        return 0;
328    }
329}
330
331static int audit_match_filetype(struct audit_context *ctx, int val)
332{
333    struct audit_names *n;
334    umode_t mode = (umode_t)val;
335
336    if (unlikely(!ctx))
337        return 0;
338
339    list_for_each_entry(n, &ctx->names_list, list) {
340        if ((n->ino != -1) &&
341            ((n->mode & S_IFMT) == mode))
342            return 1;
343    }
344
345    return 0;
346}
347
348/*
349 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
350 * ->first_trees points to its beginning, ->trees - to the current end of data.
351 * ->tree_count is the number of free entries in array pointed to by ->trees.
352 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
353 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously,
354 * it's going to remain 1-element for almost any setup) until we free context itself.
355 * References in it _are_ dropped - at the same time we free/drop aux stuff.
356 */
357
358#ifdef CONFIG_AUDIT_TREE
359static void audit_set_auditable(struct audit_context *ctx)
360{
361    if (!ctx->prio) {
362        ctx->prio = 1;
363        ctx->current_state = AUDIT_RECORD_CONTEXT;
364    }
365}
366
367static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
368{
369    struct audit_tree_refs *p = ctx->trees;
370    int left = ctx->tree_count;
371    if (likely(left)) {
372        p->c[--left] = chunk;
373        ctx->tree_count = left;
374        return 1;
375    }
376    if (!p)
377        return 0;
378    p = p->next;
379    if (p) {
380        p->c[30] = chunk;
381        ctx->trees = p;
382        ctx->tree_count = 30;
383        return 1;
384    }
385    return 0;
386}
387
388static int grow_tree_refs(struct audit_context *ctx)
389{
390    struct audit_tree_refs *p = ctx->trees;
391    ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
392    if (!ctx->trees) {
393        ctx->trees = p;
394        return 0;
395    }
396    if (p)
397        p->next = ctx->trees;
398    else
399        ctx->first_trees = ctx->trees;
400    ctx->tree_count = 31;
401    return 1;
402}
403#endif
404
405static void unroll_tree_refs(struct audit_context *ctx,
406              struct audit_tree_refs *p, int count)
407{
408#ifdef CONFIG_AUDIT_TREE
409    struct audit_tree_refs *q;
410    int n;
411    if (!p) {
412        /* we started with empty chain */
413        p = ctx->first_trees;
414        count = 31;
415        /* if the very first allocation has failed, nothing to do */
416        if (!p)
417            return;
418    }
419    n = count;
420    for (q = p; q != ctx->trees; q = q->next, n = 31) {
421        while (n--) {
422            audit_put_chunk(q->c[n]);
423            q->c[n] = NULL;
424        }
425    }
426    while (n-- > ctx->tree_count) {
427        audit_put_chunk(q->c[n]);
428        q->c[n] = NULL;
429    }
430    ctx->trees = p;
431    ctx->tree_count = count;
432#endif
433}
434
435static void free_tree_refs(struct audit_context *ctx)
436{
437    struct audit_tree_refs *p, *q;
438    for (p = ctx->first_trees; p; p = q) {
439        q = p->next;
440        kfree(p);
441    }
442}
443
444static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
445{
446#ifdef CONFIG_AUDIT_TREE
447    struct audit_tree_refs *p;
448    int n;
449    if (!tree)
450        return 0;
451    /* full ones */
452    for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
453        for (n = 0; n < 31; n++)
454            if (audit_tree_match(p->c[n], tree))
455                return 1;
456    }
457    /* partial */
458    if (p) {
459        for (n = ctx->tree_count; n < 31; n++)
460            if (audit_tree_match(p->c[n], tree))
461                return 1;
462    }
463#endif
464    return 0;
465}
466
467static int audit_compare_id(uid_t uid1,
468                struct audit_names *name,
469                unsigned long name_offset,
470                struct audit_field *f,
471                struct audit_context *ctx)
472{
473    struct audit_names *n;
474    unsigned long addr;
475    uid_t uid2;
476    int rc;
477
478    BUILD_BUG_ON(sizeof(uid_t) != sizeof(gid_t));
479
480    if (name) {
481        addr = (unsigned long)name;
482        addr += name_offset;
483
484        uid2 = *(uid_t *)addr;
485        rc = audit_comparator(uid1, f->op, uid2);
486        if (rc)
487            return rc;
488    }
489
490    if (ctx) {
491        list_for_each_entry(n, &ctx->names_list, list) {
492            addr = (unsigned long)n;
493            addr += name_offset;
494
495            uid2 = *(uid_t *)addr;
496
497            rc = audit_comparator(uid1, f->op, uid2);
498            if (rc)
499                return rc;
500        }
501    }
502    return 0;
503}
504
505static int audit_field_compare(struct task_struct *tsk,
506                   const struct cred *cred,
507                   struct audit_field *f,
508                   struct audit_context *ctx,
509                   struct audit_names *name)
510{
511    switch (f->val) {
512    /* process to file object comparisons */
513    case AUDIT_COMPARE_UID_TO_OBJ_UID:
514        return audit_compare_id(cred->uid,
515                    name, offsetof(struct audit_names, uid),
516                    f, ctx);
517    case AUDIT_COMPARE_GID_TO_OBJ_GID:
518        return audit_compare_id(cred->gid,
519                    name, offsetof(struct audit_names, gid),
520                    f, ctx);
521    case AUDIT_COMPARE_EUID_TO_OBJ_UID:
522        return audit_compare_id(cred->euid,
523                    name, offsetof(struct audit_names, uid),
524                    f, ctx);
525    case AUDIT_COMPARE_EGID_TO_OBJ_GID:
526        return audit_compare_id(cred->egid,
527                    name, offsetof(struct audit_names, gid),
528                    f, ctx);
529    case AUDIT_COMPARE_AUID_TO_OBJ_UID:
530        return audit_compare_id(tsk->loginuid,
531                    name, offsetof(struct audit_names, uid),
532                    f, ctx);
533    case AUDIT_COMPARE_SUID_TO_OBJ_UID:
534        return audit_compare_id(cred->suid,
535                    name, offsetof(struct audit_names, uid),
536                    f, ctx);
537    case AUDIT_COMPARE_SGID_TO_OBJ_GID:
538        return audit_compare_id(cred->sgid,
539                    name, offsetof(struct audit_names, gid),
540                    f, ctx);
541    case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
542        return audit_compare_id(cred->fsuid,
543                    name, offsetof(struct audit_names, uid),
544                    f, ctx);
545    case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
546        return audit_compare_id(cred->fsgid,
547                    name, offsetof(struct audit_names, gid),
548                    f, ctx);
549    /* uid comparisons */
550    case AUDIT_COMPARE_UID_TO_AUID:
551        return audit_comparator(cred->uid, f->op, tsk->loginuid);
552    case AUDIT_COMPARE_UID_TO_EUID:
553        return audit_comparator(cred->uid, f->op, cred->euid);
554    case AUDIT_COMPARE_UID_TO_SUID:
555        return audit_comparator(cred->uid, f->op, cred->suid);
556    case AUDIT_COMPARE_UID_TO_FSUID:
557        return audit_comparator(cred->uid, f->op, cred->fsuid);
558    /* auid comparisons */
559    case AUDIT_COMPARE_AUID_TO_EUID:
560        return audit_comparator(tsk->loginuid, f->op, cred->euid);
561    case AUDIT_COMPARE_AUID_TO_SUID:
562        return audit_comparator(tsk->loginuid, f->op, cred->suid);
563    case AUDIT_COMPARE_AUID_TO_FSUID:
564        return audit_comparator(tsk->loginuid, f->op, cred->fsuid);
565    /* euid comparisons */
566    case AUDIT_COMPARE_EUID_TO_SUID:
567        return audit_comparator(cred->euid, f->op, cred->suid);
568    case AUDIT_COMPARE_EUID_TO_FSUID:
569        return audit_comparator(cred->euid, f->op, cred->fsuid);
570    /* suid comparisons */
571    case AUDIT_COMPARE_SUID_TO_FSUID:
572        return audit_comparator(cred->suid, f->op, cred->fsuid);
573    /* gid comparisons */
574    case AUDIT_COMPARE_GID_TO_EGID:
575        return audit_comparator(cred->gid, f->op, cred->egid);
576    case AUDIT_COMPARE_GID_TO_SGID:
577        return audit_comparator(cred->gid, f->op, cred->sgid);
578    case AUDIT_COMPARE_GID_TO_FSGID:
579        return audit_comparator(cred->gid, f->op, cred->fsgid);
580    /* egid comparisons */
581    case AUDIT_COMPARE_EGID_TO_SGID:
582        return audit_comparator(cred->egid, f->op, cred->sgid);
583    case AUDIT_COMPARE_EGID_TO_FSGID:
584        return audit_comparator(cred->egid, f->op, cred->fsgid);
585    /* sgid comparison */
586    case AUDIT_COMPARE_SGID_TO_FSGID:
587        return audit_comparator(cred->sgid, f->op, cred->fsgid);
588    default:
589        WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n");
590        return 0;
591    }
592    return 0;
593}
594
595/* Determine if any context name data matches a rule's watch data */
596/* Compare a task_struct with an audit_rule. Return 1 on match, 0
597 * otherwise.
598 *
599 * If task_creation is true, this is an explicit indication that we are
600 * filtering a task rule at task creation time. This and tsk == current are
601 * the only situations where tsk->cred may be accessed without an rcu read lock.
602 */
603static int audit_filter_rules(struct task_struct *tsk,
604                  struct audit_krule *rule,
605                  struct audit_context *ctx,
606                  struct audit_names *name,
607                  enum audit_state *state,
608                  bool task_creation)
609{
610    const struct cred *cred;
611    int i, need_sid = 1;
612    u32 sid;
613
614    cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
615
616    for (i = 0; i < rule->field_count; i++) {
617        struct audit_field *f = &rule->fields[i];
618        struct audit_names *n;
619        int result = 0;
620
621        switch (f->type) {
622        case AUDIT_PID:
623            result = audit_comparator(tsk->pid, f->op, f->val);
624            break;
625        case AUDIT_PPID:
626            if (ctx) {
627                if (!ctx->ppid)
628                    ctx->ppid = sys_getppid();
629                result = audit_comparator(ctx->ppid, f->op, f->val);
630            }
631            break;
632        case AUDIT_UID:
633            result = audit_comparator(cred->uid, f->op, f->val);
634            break;
635        case AUDIT_EUID:
636            result = audit_comparator(cred->euid, f->op, f->val);
637            break;
638        case AUDIT_SUID:
639            result = audit_comparator(cred->suid, f->op, f->val);
640            break;
641        case AUDIT_FSUID:
642            result = audit_comparator(cred->fsuid, f->op, f->val);
643            break;
644        case AUDIT_GID:
645            result = audit_comparator(cred->gid, f->op, f->val);
646            break;
647        case AUDIT_EGID:
648            result = audit_comparator(cred->egid, f->op, f->val);
649            break;
650        case AUDIT_SGID:
651            result = audit_comparator(cred->sgid, f->op, f->val);
652            break;
653        case AUDIT_FSGID:
654            result = audit_comparator(cred->fsgid, f->op, f->val);
655            break;
656        case AUDIT_PERS:
657            result = audit_comparator(tsk->personality, f->op, f->val);
658            break;
659        case AUDIT_ARCH:
660            if (ctx)
661                result = audit_comparator(ctx->arch, f->op, f->val);
662            break;
663
664        case AUDIT_EXIT:
665            if (ctx && ctx->return_valid)
666                result = audit_comparator(ctx->return_code, f->op, f->val);
667            break;
668        case AUDIT_SUCCESS:
669            if (ctx && ctx->return_valid) {
670                if (f->val)
671                    result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
672                else
673                    result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
674            }
675            break;
676        case AUDIT_DEVMAJOR:
677            if (name) {
678                if (audit_comparator(MAJOR(name->dev), f->op, f->val) ||
679                    audit_comparator(MAJOR(name->rdev), f->op, f->val))
680                    ++result;
681            } else if (ctx) {
682                list_for_each_entry(n, &ctx->names_list, list) {
683                    if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
684                        audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
685                        ++result;
686                        break;
687                    }
688                }
689            }
690            break;
691        case AUDIT_DEVMINOR:
692            if (name) {
693                if (audit_comparator(MINOR(name->dev), f->op, f->val) ||
694                    audit_comparator(MINOR(name->rdev), f->op, f->val))
695                    ++result;
696            } else if (ctx) {
697                list_for_each_entry(n, &ctx->names_list, list) {
698                    if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
699                        audit_comparator(MINOR(n->rdev), f->op, f->val)) {
700                        ++result;
701                        break;
702                    }
703                }
704            }
705            break;
706        case AUDIT_INODE:
707            if (name)
708                result = (name->ino == f->val);
709            else if (ctx) {
710                list_for_each_entry(n, &ctx->names_list, list) {
711                    if (audit_comparator(n->ino, f->op, f->val)) {
712                        ++result;
713                        break;
714                    }
715                }
716            }
717            break;
718        case AUDIT_OBJ_UID:
719            if (name) {
720                result = audit_comparator(name->uid, f->op, f->val);
721            } else if (ctx) {
722                list_for_each_entry(n, &ctx->names_list, list) {
723                    if (audit_comparator(n->uid, f->op, f->val)) {
724                        ++result;
725                        break;
726                    }
727                }
728            }
729            break;
730        case AUDIT_OBJ_GID:
731            if (name) {
732                result = audit_comparator(name->gid, f->op, f->val);
733            } else if (ctx) {
734                list_for_each_entry(n, &ctx->names_list, list) {
735                    if (audit_comparator(n->gid, f->op, f->val)) {
736                        ++result;
737                        break;
738                    }
739                }
740            }
741            break;
742        case AUDIT_WATCH:
743            if (name)
744                result = audit_watch_compare(rule->watch, name->ino, name->dev);
745            break;
746        case AUDIT_DIR:
747            if (ctx)
748                result = match_tree_refs(ctx, rule->tree);
749            break;
750        case AUDIT_LOGINUID:
751            result = 0;
752            if (ctx)
753                result = audit_comparator(tsk->loginuid, f->op, f->val);
754            break;
755        case AUDIT_SUBJ_USER:
756        case AUDIT_SUBJ_ROLE:
757        case AUDIT_SUBJ_TYPE:
758        case AUDIT_SUBJ_SEN:
759        case AUDIT_SUBJ_CLR:
760            /* NOTE: this may return negative values indicating
761               a temporary error. We simply treat this as a
762               match for now to avoid losing information that
763               may be wanted. An error message will also be
764               logged upon error */
765            if (f->lsm_rule) {
766                if (need_sid) {
767                    security_task_getsecid(tsk, &sid);
768                    need_sid = 0;
769                }
770                result = security_audit_rule_match(sid, f->type,
771                                                  f->op,
772                                                  f->lsm_rule,
773                                                  ctx);
774            }
775            break;
776        case AUDIT_OBJ_USER:
777        case AUDIT_OBJ_ROLE:
778        case AUDIT_OBJ_TYPE:
779        case AUDIT_OBJ_LEV_LOW:
780        case AUDIT_OBJ_LEV_HIGH:
781            /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
782               also applies here */
783            if (f->lsm_rule) {
784                /* Find files that match */
785                if (name) {
786                    result = security_audit_rule_match(
787                               name->osid, f->type, f->op,
788                               f->lsm_rule, ctx);
789                } else if (ctx) {
790                    list_for_each_entry(n, &ctx->names_list, list) {
791                        if (security_audit_rule_match(n->osid, f->type,
792                                          f->op, f->lsm_rule,
793                                          ctx)) {
794                            ++result;
795                            break;
796                        }
797                    }
798                }
799                /* Find ipc objects that match */
800                if (!ctx || ctx->type != AUDIT_IPC)
801                    break;
802                if (security_audit_rule_match(ctx->ipc.osid,
803                                  f->type, f->op,
804                                  f->lsm_rule, ctx))
805                    ++result;
806            }
807            break;
808        case AUDIT_ARG0:
809        case AUDIT_ARG1:
810        case AUDIT_ARG2:
811        case AUDIT_ARG3:
812            if (ctx)
813                result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
814            break;
815        case AUDIT_FILTERKEY:
816            /* ignore this field for filtering */
817            result = 1;
818            break;
819        case AUDIT_PERM:
820            result = audit_match_perm(ctx, f->val);
821            break;
822        case AUDIT_FILETYPE:
823            result = audit_match_filetype(ctx, f->val);
824            break;
825        case AUDIT_FIELD_COMPARE:
826            result = audit_field_compare(tsk, cred, f, ctx, name);
827            break;
828        }
829        if (!result)
830            return 0;
831    }
832
833    if (ctx) {
834        if (rule->prio <= ctx->prio)
835            return 0;
836        if (rule->filterkey) {
837            kfree(ctx->filterkey);
838            ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
839        }
840        ctx->prio = rule->prio;
841    }
842    switch (rule->action) {
843    case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
844    case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
845    }
846    return 1;
847}
848
849/* At process creation time, we can determine if system-call auditing is
850 * completely disabled for this task. Since we only have the task
851 * structure at this point, we can only check uid and gid.
852 */
853static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
854{
855    struct audit_entry *e;
856    enum audit_state state;
857
858    rcu_read_lock();
859    list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
860        if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
861                       &state, true)) {
862            if (state == AUDIT_RECORD_CONTEXT)
863                *key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
864            rcu_read_unlock();
865            return state;
866        }
867    }
868    rcu_read_unlock();
869    return AUDIT_BUILD_CONTEXT;
870}
871
872/* At syscall entry and exit time, this filter is called if the
873 * audit_state is not low enough that auditing cannot take place, but is
874 * also not high enough that we already know we have to write an audit
875 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
876 */
877static enum audit_state audit_filter_syscall(struct task_struct *tsk,
878                         struct audit_context *ctx,
879                         struct list_head *list)
880{
881    struct audit_entry *e;
882    enum audit_state state;
883
884    if (audit_pid && tsk->tgid == audit_pid)
885        return AUDIT_DISABLED;
886
887    rcu_read_lock();
888    if (!list_empty(list)) {
889        int word = AUDIT_WORD(ctx->major);
890        int bit = AUDIT_BIT(ctx->major);
891
892        list_for_each_entry_rcu(e, list, list) {
893            if ((e->rule.mask[word] & bit) == bit &&
894                audit_filter_rules(tsk, &e->rule, ctx, NULL,
895                           &state, false)) {
896                rcu_read_unlock();
897                ctx->current_state = state;
898                return state;
899            }
900        }
901    }
902    rcu_read_unlock();
903    return AUDIT_BUILD_CONTEXT;
904}
905
906/*
907 * Given an audit_name check the inode hash table to see if they match.
908 * Called holding the rcu read lock to protect the use of audit_inode_hash
909 */
910static int audit_filter_inode_name(struct task_struct *tsk,
911                   struct audit_names *n,
912                   struct audit_context *ctx) {
913    int word, bit;
914    int h = audit_hash_ino((u32)n->ino);
915    struct list_head *list = &audit_inode_hash[h];
916    struct audit_entry *e;
917    enum audit_state state;
918
919    word = AUDIT_WORD(ctx->major);
920    bit = AUDIT_BIT(ctx->major);
921
922    if (list_empty(list))
923        return 0;
924
925    list_for_each_entry_rcu(e, list, list) {
926        if ((e->rule.mask[word] & bit) == bit &&
927            audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
928            ctx->current_state = state;
929            return 1;
930        }
931    }
932
933    return 0;
934}
935
936/* At syscall exit time, this filter is called if any audit_names have been
937 * collected during syscall processing. We only check rules in sublists at hash
938 * buckets applicable to the inode numbers in audit_names.
939 * Regarding audit_state, same rules apply as for audit_filter_syscall().
940 */
941void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
942{
943    struct audit_names *n;
944
945    if (audit_pid && tsk->tgid == audit_pid)
946        return;
947
948    rcu_read_lock();
949
950    list_for_each_entry(n, &ctx->names_list, list) {
951        if (audit_filter_inode_name(tsk, n, ctx))
952            break;
953    }
954    rcu_read_unlock();
955}
956
957static inline struct audit_context *audit_get_context(struct task_struct *tsk,
958                              int return_valid,
959                              long return_code)
960{
961    struct audit_context *context = tsk->audit_context;
962
963    if (!context)
964        return NULL;
965    context->return_valid = return_valid;
966
967    /*
968     * we need to fix up the return code in the audit logs if the actual
969     * return codes are later going to be fixed up by the arch specific
970     * signal handlers
971     *
972     * This is actually a test for:
973     * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
974     * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
975     *
976     * but is faster than a bunch of ||
977     */
978    if (unlikely(return_code <= -ERESTARTSYS) &&
979        (return_code >= -ERESTART_RESTARTBLOCK) &&
980        (return_code != -ENOIOCTLCMD))
981        context->return_code = -EINTR;
982    else
983        context->return_code = return_code;
984
985    if (context->in_syscall && !context->dummy) {
986        audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
987        audit_filter_inodes(tsk, context);
988    }
989
990    tsk->audit_context = NULL;
991    return context;
992}
993
994static inline void audit_free_names(struct audit_context *context)
995{
996    struct audit_names *n, *next;
997
998#if AUDIT_DEBUG == 2
999    if (context->put_count + context->ino_count != context->name_count) {
1000        printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
1001               " name_count=%d put_count=%d"
1002               " ino_count=%d [NOT freeing]\n",
1003               __FILE__, __LINE__,
1004               context->serial, context->major, context->in_syscall,
1005               context->name_count, context->put_count,
1006               context->ino_count);
1007        list_for_each_entry(n, &context->names_list, list) {
1008            printk(KERN_ERR "names[%d] = %p = %s\n", i,
1009                   n->name, n->name ?: "(null)");
1010        }
1011        dump_stack();
1012        return;
1013    }
1014#endif
1015#if AUDIT_DEBUG
1016    context->put_count = 0;
1017    context->ino_count = 0;
1018#endif
1019
1020    list_for_each_entry_safe(n, next, &context->names_list, list) {
1021        list_del(&n->list);
1022        if (n->name && n->name_put)
1023            __putname(n->name);
1024        if (n->should_free)
1025            kfree(n);
1026    }
1027    context->name_count = 0;
1028    path_put(&context->pwd);
1029    context->pwd.dentry = NULL;
1030    context->pwd.mnt = NULL;
1031}
1032
1033static inline void audit_free_aux(struct audit_context *context)
1034{
1035    struct audit_aux_data *aux;
1036
1037    while ((aux = context->aux)) {
1038        context->aux = aux->next;
1039        kfree(aux);
1040    }
1041    while ((aux = context->aux_pids)) {
1042        context->aux_pids = aux->next;
1043        kfree(aux);
1044    }
1045}
1046
1047static inline void audit_zero_context(struct audit_context *context,
1048                      enum audit_state state)
1049{
1050    memset(context, 0, sizeof(*context));
1051    context->state = state;
1052    context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1053}
1054
1055static inline struct audit_context *audit_alloc_context(enum audit_state state)
1056{
1057    struct audit_context *context;
1058
1059    if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
1060        return NULL;
1061    audit_zero_context(context, state);
1062    INIT_LIST_HEAD(&context->killed_trees);
1063    INIT_LIST_HEAD(&context->names_list);
1064    return context;
1065}
1066
1067/**
1068 * audit_alloc - allocate an audit context block for a task
1069 * @tsk: task
1070 *
1071 * Filter on the task information and allocate a per-task audit context
1072 * if necessary. Doing so turns on system call auditing for the
1073 * specified task. This is called from copy_process, so no lock is
1074 * needed.
1075 */
1076int audit_alloc(struct task_struct *tsk)
1077{
1078    struct audit_context *context;
1079    enum audit_state state;
1080    char *key = NULL;
1081
1082    if (likely(!audit_ever_enabled))
1083        return 0; /* Return if not auditing. */
1084
1085    state = audit_filter_task(tsk, &key);
1086    if (state == AUDIT_DISABLED)
1087        return 0;
1088
1089    if (!(context = audit_alloc_context(state))) {
1090        kfree(key);
1091        audit_log_lost("out of memory in audit_alloc");
1092        return -ENOMEM;
1093    }
1094    context->filterkey = key;
1095
1096    tsk->audit_context = context;
1097    set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
1098    return 0;
1099}
1100
1101static inline void audit_free_context(struct audit_context *context)
1102{
1103    struct audit_context *previous;
1104    int count = 0;
1105
1106    do {
1107        previous = context->previous;
1108        if (previous || (count && count < 10)) {
1109            ++count;
1110            printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
1111                   " freeing multiple contexts (%d)\n",
1112                   context->serial, context->major,
1113                   context->name_count, count);
1114        }
1115        audit_free_names(context);
1116        unroll_tree_refs(context, NULL, 0);
1117        free_tree_refs(context);
1118        audit_free_aux(context);
1119        kfree(context->filterkey);
1120        kfree(context->sockaddr);
1121        kfree(context);
1122        context = previous;
1123    } while (context);
1124    if (count >= 10)
1125        printk(KERN_ERR "audit: freed %d contexts\n", count);
1126}
1127
1128void audit_log_task_context(struct audit_buffer *ab)
1129{
1130    char *ctx = NULL;
1131    unsigned len;
1132    int error;
1133    u32 sid;
1134
1135    security_task_getsecid(current, &sid);
1136    if (!sid)
1137        return;
1138
1139    error = security_secid_to_secctx(sid, &ctx, &len);
1140    if (error) {
1141        if (error != -EINVAL)
1142            goto error_path;
1143        return;
1144    }
1145
1146    audit_log_format(ab, " subj=%s", ctx);
1147    security_release_secctx(ctx, len);
1148    return;
1149
1150error_path:
1151    audit_panic("error in audit_log_task_context");
1152    return;
1153}
1154
1155EXPORT_SYMBOL(audit_log_task_context);
1156
1157static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
1158{
1159    char name[sizeof(tsk->comm)];
1160    struct mm_struct *mm = tsk->mm;
1161    struct vm_area_struct *vma;
1162
1163    /* tsk == current */
1164
1165    get_task_comm(name, tsk);
1166    audit_log_format(ab, " comm=");
1167    audit_log_untrustedstring(ab, name);
1168
1169    if (mm) {
1170        down_read(&mm->mmap_sem);
1171        vma = mm->mmap;
1172        while (vma) {
1173            if ((vma->vm_flags & VM_EXECUTABLE) &&
1174                vma->vm_file) {
1175                audit_log_d_path(ab, " exe=",
1176                         &vma->vm_file->f_path);
1177                break;
1178            }
1179            vma = vma->vm_next;
1180        }
1181        up_read(&mm->mmap_sem);
1182    }
1183    audit_log_task_context(ab);
1184}
1185
1186static int audit_log_pid_context(struct audit_context *context, pid_t pid,
1187                 uid_t auid, uid_t uid, unsigned int sessionid,
1188                 u32 sid, char *comm)
1189{
1190    struct audit_buffer *ab;
1191    char *ctx = NULL;
1192    u32 len;
1193    int rc = 0;
1194
1195    ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
1196    if (!ab)
1197        return rc;
1198
1199    audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
1200             uid, sessionid);
1201    if (security_secid_to_secctx(sid, &ctx, &len)) {
1202        audit_log_format(ab, " obj=(none)");
1203        rc = 1;
1204    } else {
1205        audit_log_format(ab, " obj=%s", ctx);
1206        security_release_secctx(ctx, len);
1207    }
1208    audit_log_format(ab, " ocomm=");
1209    audit_log_untrustedstring(ab, comm);
1210    audit_log_end(ab);
1211
1212    return rc;
1213}
1214
1215/*
1216 * to_send and len_sent accounting are very loose estimates. We aren't
1217 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
1218 * within about 500 bytes (next page boundary)
1219 *
1220 * why snprintf? an int is up to 12 digits long. if we just assumed when
1221 * logging that a[%d]= was going to be 16 characters long we would be wasting
1222 * space in every audit message. In one 7500 byte message we can log up to
1223 * about 1000 min size arguments. That comes down to about 50% waste of space
1224 * if we didn't do the snprintf to find out how long arg_num_len was.
1225 */
1226static int audit_log_single_execve_arg(struct audit_context *context,
1227                    struct audit_buffer **ab,
1228                    int arg_num,
1229                    size_t *len_sent,
1230                    const char __user *p,
1231                    char *buf)
1232{
1233    char arg_num_len_buf[12];
1234    const char __user *tmp_p = p;
1235    /* how many digits are in arg_num? 5 is the length of ' a=""' */
1236    size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5;
1237    size_t len, len_left, to_send;
1238    size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1239    unsigned int i, has_cntl = 0, too_long = 0;
1240    int ret;
1241
1242    /* strnlen_user includes the null we don't want to send */
1243    len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1244
1245    /*
1246     * We just created this mm, if we can't find the strings
1247     * we just copied into it something is _very_ wrong. Similar
1248     * for strings that are too long, we should not have created
1249     * any.
1250     */
1251    if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1252        WARN_ON(1);
1253        send_sig(SIGKILL, current, 0);
1254        return -1;
1255    }
1256
1257    /* walk the whole argument looking for non-ascii chars */
1258    do {
1259        if (len_left > MAX_EXECVE_AUDIT_LEN)
1260            to_send = MAX_EXECVE_AUDIT_LEN;
1261        else
1262            to_send = len_left;
1263        ret = copy_from_user(buf, tmp_p, to_send);
1264        /*
1265         * There is no reason for this copy to be short. We just
1266         * copied them here, and the mm hasn't been exposed to user-
1267         * space yet.
1268         */
1269        if (ret) {
1270            WARN_ON(1);
1271            send_sig(SIGKILL, current, 0);
1272            return -1;
1273        }
1274        buf[to_send] = '\0';
1275        has_cntl = audit_string_contains_control(buf, to_send);
1276        if (has_cntl) {
1277            /*
1278             * hex messages get logged as 2 bytes, so we can only
1279             * send half as much in each message
1280             */
1281            max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1282            break;
1283        }
1284        len_left -= to_send;
1285        tmp_p += to_send;
1286    } while (len_left > 0);
1287
1288    len_left = len;
1289
1290    if (len > max_execve_audit_len)
1291        too_long = 1;
1292
1293    /* rewalk the argument actually logging the message */
1294    for (i = 0; len_left > 0; i++) {
1295        int room_left;
1296
1297        if (len_left > max_execve_audit_len)
1298            to_send = max_execve_audit_len;
1299        else
1300            to_send = len_left;
1301
1302        /* do we have space left to send this argument in this ab? */
1303        room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1304        if (has_cntl)
1305            room_left -= (to_send * 2);
1306        else
1307            room_left -= to_send;
1308        if (room_left < 0) {
1309            *len_sent = 0;
1310            audit_log_end(*ab);
1311            *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1312            if (!*ab)
1313                return 0;
1314        }
1315
1316        /*
1317         * first record needs to say how long the original string was
1318         * so we can be sure nothing was lost.
1319         */
1320        if ((i == 0) && (too_long))
1321            audit_log_format(*ab, " a%d_len=%zu", arg_num,
1322                     has_cntl ? 2*len : len);
1323
1324        /*
1325         * normally arguments are small enough to fit and we already
1326         * filled buf above when we checked for control characters
1327         * so don't bother with another copy_from_user
1328         */
1329        if (len >= max_execve_audit_len)
1330            ret = copy_from_user(buf, p, to_send);
1331        else
1332            ret = 0;
1333        if (ret) {
1334            WARN_ON(1);
1335            send_sig(SIGKILL, current, 0);
1336            return -1;
1337        }
1338        buf[to_send] = '\0';
1339
1340        /* actually log it */
1341        audit_log_format(*ab, " a%d", arg_num);
1342        if (too_long)
1343            audit_log_format(*ab, "[%d]", i);
1344        audit_log_format(*ab, "=");
1345        if (has_cntl)
1346            audit_log_n_hex(*ab, buf, to_send);
1347        else
1348            audit_log_string(*ab, buf);
1349
1350        p += to_send;
1351        len_left -= to_send;
1352        *len_sent += arg_num_len;
1353        if (has_cntl)
1354            *len_sent += to_send * 2;
1355        else
1356            *len_sent += to_send;
1357    }
1358    /* include the null we didn't log */
1359    return len + 1;
1360}
1361
1362static void audit_log_execve_info(struct audit_context *context,
1363                  struct audit_buffer **ab,
1364                  struct audit_aux_data_execve *axi)
1365{
1366    int i, len;
1367    size_t len_sent = 0;
1368    const char __user *p;
1369    char *buf;
1370
1371    if (axi->mm != current->mm)
1372        return; /* execve failed, no additional info */
1373
1374    p = (const char __user *)axi->mm->arg_start;
1375
1376    audit_log_format(*ab, "argc=%d", axi->argc);
1377
1378    /*
1379     * we need some kernel buffer to hold the userspace args. Just
1380     * allocate one big one rather than allocating one of the right size
1381     * for every single argument inside audit_log_single_execve_arg()
1382     * should be <8k allocation so should be pretty safe.
1383     */
1384    buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1385    if (!buf) {
1386        audit_panic("out of memory for argv string\n");
1387        return;
1388    }
1389
1390    for (i = 0; i < axi->argc; i++) {
1391        len = audit_log_single_execve_arg(context, ab, i,
1392                          &len_sent, p, buf);
1393        if (len <= 0)
1394            break;
1395        p += len;
1396    }
1397    kfree(buf);
1398}
1399
1400static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
1401{
1402    int i;
1403
1404    audit_log_format(ab, " %s=", prefix);
1405    CAP_FOR_EACH_U32(i) {
1406        audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
1407    }
1408}
1409
1410static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1411{
1412    kernel_cap_t *perm = &name->fcap.permitted;
1413    kernel_cap_t *inh = &name->fcap.inheritable;
1414    int log = 0;
1415
1416    if (!cap_isclear(*perm)) {
1417        audit_log_cap(ab, "cap_fp", perm);
1418        log = 1;
1419    }
1420    if (!cap_isclear(*inh)) {
1421        audit_log_cap(ab, "cap_fi", inh);
1422        log = 1;
1423    }
1424
1425    if (log)
1426        audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver);
1427}
1428
1429static void show_special(struct audit_context *context, int *call_panic)
1430{
1431    struct audit_buffer *ab;
1432    int i;
1433
1434    ab = audit_log_start(context, GFP_KERNEL, context->type);
1435    if (!ab)
1436        return;
1437
1438    switch (context->type) {
1439    case AUDIT_SOCKETCALL: {
1440        int nargs = context->socketcall.nargs;
1441        audit_log_format(ab, "nargs=%d", nargs);
1442        for (i = 0; i < nargs; i++)
1443            audit_log_format(ab, " a%d=%lx", i,
1444                context->socketcall.args[i]);
1445        break; }
1446    case AUDIT_IPC: {
1447        u32 osid = context->ipc.osid;
1448
1449        audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1450             context->ipc.uid, context->ipc.gid, context->ipc.mode);
1451        if (osid) {
1452            char *ctx = NULL;
1453            u32 len;
1454            if (security_secid_to_secctx(osid, &ctx, &len)) {
1455                audit_log_format(ab, " osid=%u", osid);
1456                *call_panic = 1;
1457            } else {
1458                audit_log_format(ab, " obj=%s", ctx);
1459                security_release_secctx(ctx, len);
1460            }
1461        }
1462        if (context->ipc.has_perm) {
1463            audit_log_end(ab);
1464            ab = audit_log_start(context, GFP_KERNEL,
1465                         AUDIT_IPC_SET_PERM);
1466            audit_log_format(ab,
1467                "qbytes=%lx ouid=%u ogid=%u mode=%#ho",
1468                context->ipc.qbytes,
1469                context->ipc.perm_uid,
1470                context->ipc.perm_gid,
1471                context->ipc.perm_mode);
1472            if (!ab)
1473                return;
1474        }
1475        break; }
1476    case AUDIT_MQ_OPEN: {
1477        audit_log_format(ab,
1478            "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
1479            "mq_msgsize=%ld mq_curmsgs=%ld",
1480            context->mq_open.oflag, context->mq_open.mode,
1481            context->mq_open.attr.mq_flags,
1482            context->mq_open.attr.mq_maxmsg,
1483            context->mq_open.attr.mq_msgsize,
1484            context->mq_open.attr.mq_curmsgs);
1485        break; }
1486    case AUDIT_MQ_SENDRECV: {
1487        audit_log_format(ab,
1488            "mqdes=%d msg_len=%zd msg_prio=%u "
1489            "abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1490            context->mq_sendrecv.mqdes,
1491            context->mq_sendrecv.msg_len,
1492            context->mq_sendrecv.msg_prio,
1493            context->mq_sendrecv.abs_timeout.tv_sec,
1494            context->mq_sendrecv.abs_timeout.tv_nsec);
1495        break; }
1496    case AUDIT_MQ_NOTIFY: {
1497        audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1498                context->mq_notify.mqdes,
1499                context->mq_notify.sigev_signo);
1500        break; }
1501    case AUDIT_MQ_GETSETATTR: {
1502        struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1503        audit_log_format(ab,
1504            "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1505            "mq_curmsgs=%ld ",
1506            context->mq_getsetattr.mqdes,
1507            attr->mq_flags, attr->mq_maxmsg,
1508            attr->mq_msgsize, attr->mq_curmsgs);
1509        break; }
1510    case AUDIT_CAPSET: {
1511        audit_log_format(ab, "pid=%d", context->capset.pid);
1512        audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1513        audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1514        audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1515        break; }
1516    case AUDIT_MMAP: {
1517        audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
1518                 context->mmap.flags);
1519        break; }
1520    }
1521    audit_log_end(ab);
1522}
1523
1524static void audit_log_name(struct audit_context *context, struct audit_names *n,
1525               int record_num, int *call_panic)
1526{
1527    struct audit_buffer *ab;
1528    ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1529    if (!ab)
1530        return; /* audit_panic has been called */
1531
1532    audit_log_format(ab, "item=%d", record_num);
1533
1534    if (n->name) {
1535        switch (n->name_len) {
1536        case AUDIT_NAME_FULL:
1537            /* log the full path */
1538            audit_log_format(ab, " name=");
1539            audit_log_untrustedstring(ab, n->name);
1540            break;
1541        case 0:
1542            /* name was specified as a relative path and the
1543             * directory component is the cwd */
1544            audit_log_d_path(ab, " name=", &context->pwd);
1545            break;
1546        default:
1547            /* log the name's directory component */
1548            audit_log_format(ab, " name=");
1549            audit_log_n_untrustedstring(ab, n->name,
1550                            n->name_len);
1551        }
1552    } else
1553        audit_log_format(ab, " name=(null)");
1554
1555    if (n->ino != (unsigned long)-1) {
1556        audit_log_format(ab, " inode=%lu"
1557                 " dev=%02x:%02x mode=%#ho"
1558                 " ouid=%u ogid=%u rdev=%02x:%02x",
1559                 n->ino,
1560                 MAJOR(n->dev),
1561                 MINOR(n->dev),
1562                 n->mode,
1563                 n->uid,
1564                 n->gid,
1565                 MAJOR(n->rdev),
1566                 MINOR(n->rdev));
1567    }
1568    if (n->osid != 0) {
1569        char *ctx = NULL;
1570        u32 len;
1571        if (security_secid_to_secctx(
1572            n->osid, &ctx, &len)) {
1573            audit_log_format(ab, " osid=%u", n->osid);
1574            *call_panic = 2;
1575        } else {
1576            audit_log_format(ab, " obj=%s", ctx);
1577            security_release_secctx(ctx, len);
1578        }
1579    }
1580
1581    audit_log_fcaps(ab, n);
1582
1583    audit_log_end(ab);
1584}
1585
1586static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1587{
1588    const struct cred *cred;
1589    int i, call_panic = 0;
1590    struct audit_buffer *ab;
1591    struct audit_aux_data *aux;
1592    const char *tty;
1593    struct audit_names *n;
1594
1595    /* tsk == current */
1596    context->pid = tsk->pid;
1597    if (!context->ppid)
1598        context->ppid = sys_getppid();
1599    cred = current_cred();
1600    context->uid = cred->uid;
1601    context->gid = cred->gid;
1602    context->euid = cred->euid;
1603    context->suid = cred->suid;
1604    context->fsuid = cred->fsuid;
1605    context->egid = cred->egid;
1606    context->sgid = cred->sgid;
1607    context->fsgid = cred->fsgid;
1608    context->personality = tsk->personality;
1609
1610    ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1611    if (!ab)
1612        return; /* audit_panic has been called */
1613    audit_log_format(ab, "arch=%x syscall=%d",
1614             context->arch, context->major);
1615    if (context->personality != PER_LINUX)
1616        audit_log_format(ab, " per=%lx", context->personality);
1617    if (context->return_valid)
1618        audit_log_format(ab, " success=%s exit=%ld",
1619                 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1620                 context->return_code);
1621
1622    spin_lock_irq(&tsk->sighand->siglock);
1623    if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1624        tty = tsk->signal->tty->name;
1625    else
1626        tty = "(none)";
1627    spin_unlock_irq(&tsk->sighand->siglock);
1628
1629    audit_log_format(ab,
1630          " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
1631          " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1632          " euid=%u suid=%u fsuid=%u"
1633          " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1634          context->argv[0],
1635          context->argv[1],
1636          context->argv[2],
1637          context->argv[3],
1638          context->name_count,
1639          context->ppid,
1640          context->pid,
1641          tsk->loginuid,
1642          context->uid,
1643          context->gid,
1644          context->euid, context->suid, context->fsuid,
1645          context->egid, context->sgid, context->fsgid, tty,
1646          tsk->sessionid);
1647
1648
1649    audit_log_task_info(ab, tsk);
1650    audit_log_key(ab, context->filterkey);
1651    audit_log_end(ab);
1652
1653    for (aux = context->aux; aux; aux = aux->next) {
1654
1655        ab = audit_log_start(context, GFP_KERNEL, aux->type);
1656        if (!ab)
1657            continue; /* audit_panic has been called */
1658
1659        switch (aux->type) {
1660
1661        case AUDIT_EXECVE: {
1662            struct audit_aux_data_execve *axi = (void *)aux;
1663            audit_log_execve_info(context, &ab, axi);
1664            break; }
1665
1666        case AUDIT_BPRM_FCAPS: {
1667            struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1668            audit_log_format(ab, "fver=%x", axs->fcap_ver);
1669            audit_log_cap(ab, "fp", &axs->fcap.permitted);
1670            audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1671            audit_log_format(ab, " fe=%d", axs->fcap.fE);
1672            audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1673            audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1674            audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1675            audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
1676            audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
1677            audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
1678            break; }
1679
1680        }
1681        audit_log_end(ab);
1682    }
1683
1684    if (context->type)
1685        show_special(context, &call_panic);
1686
1687    if (context->fds[0] >= 0) {
1688        ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1689        if (ab) {
1690            audit_log_format(ab, "fd0=%d fd1=%d",
1691                    context->fds[0], context->fds[1]);
1692            audit_log_end(ab);
1693        }
1694    }
1695
1696    if (context->sockaddr_len) {
1697        ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1698        if (ab) {
1699            audit_log_format(ab, "saddr=");
1700            audit_log_n_hex(ab, (void *)context->sockaddr,
1701                    context->sockaddr_len);
1702            audit_log_end(ab);
1703        }
1704    }
1705
1706    for (aux = context->aux_pids; aux; aux = aux->next) {
1707        struct audit_aux_data_pids *axs = (void *)aux;
1708
1709        for (i = 0; i < axs->pid_count; i++)
1710            if (audit_log_pid_context(context, axs->target_pid[i],
1711                          axs->target_auid[i],
1712                          axs->target_uid[i],
1713                          axs->target_sessionid[i],
1714                          axs->target_sid[i],
1715                          axs->target_comm[i]))
1716                call_panic = 1;
1717    }
1718
1719    if (context->target_pid &&
1720        audit_log_pid_context(context, context->target_pid,
1721                  context->target_auid, context->target_uid,
1722                  context->target_sessionid,
1723                  context->target_sid, context->target_comm))
1724            call_panic = 1;
1725
1726    if (context->pwd.dentry && context->pwd.mnt) {
1727        ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1728        if (ab) {
1729            audit_log_d_path(ab, " cwd=", &context->pwd);
1730            audit_log_end(ab);
1731        }
1732    }
1733
1734    i = 0;
1735    list_for_each_entry(n, &context->names_list, list)
1736        audit_log_name(context, n, i++, &call_panic);
1737
1738    /* Send end of event record to help user space know we are finished */
1739    ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1740    if (ab)
1741        audit_log_end(ab);
1742    if (call_panic)
1743        audit_panic("error converting sid to string");
1744}
1745
1746/**
1747 * audit_free - free a per-task audit context
1748 * @tsk: task whose audit context block to free
1749 *
1750 * Called from copy_process and do_exit
1751 */
1752void __audit_free(struct task_struct *tsk)
1753{
1754    struct audit_context *context;
1755
1756    context = audit_get_context(tsk, 0, 0);
1757    if (!context)
1758        return;
1759
1760    /* Check for system calls that do not go through the exit
1761     * function (e.g., exit_group), then free context block.
1762     * We use GFP_ATOMIC here because we might be doing this
1763     * in the context of the idle thread */
1764    /* that can happen only if we are called from do_exit() */
1765    if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1766        audit_log_exit(context, tsk);
1767    if (!list_empty(&context->killed_trees))
1768        audit_kill_trees(&context->killed_trees);
1769
1770    audit_free_context(context);
1771}
1772
1773/**
1774 * audit_syscall_entry - fill in an audit record at syscall entry
1775 * @arch: architecture type
1776 * @major: major syscall type (function)
1777 * @a1: additional syscall register 1
1778 * @a2: additional syscall register 2
1779 * @a3: additional syscall register 3
1780 * @a4: additional syscall register 4
1781 *
1782 * Fill in audit context at syscall entry. This only happens if the
1783 * audit context was created when the task was created and the state or
1784 * filters demand the audit context be built. If the state from the
1785 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1786 * then the record will be written at syscall exit time (otherwise, it
1787 * will only be written if another part of the kernel requests that it
1788 * be written).
1789 */
1790void __audit_syscall_entry(int arch, int major,
1791             unsigned long a1, unsigned long a2,
1792             unsigned long a3, unsigned long a4)
1793{
1794    struct task_struct *tsk = current;
1795    struct audit_context *context = tsk->audit_context;
1796    enum audit_state state;
1797
1798    if (!context)
1799        return;
1800
1801    /*
1802     * This happens only on certain architectures that make system
1803     * calls in kernel_thread via the entry.S interface, instead of
1804     * with direct calls. (If you are porting to a new
1805     * architecture, hitting this condition can indicate that you
1806     * got the _exit/_leave calls backward in entry.S.)
1807     *
1808     * i386 no
1809     * x86_64 no
1810     * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S)
1811     *
1812     * This also happens with vm86 emulation in a non-nested manner
1813     * (entries without exits), so this case must be caught.
1814     */
1815    if (context->in_syscall) {
1816        struct audit_context *newctx;
1817
1818#if AUDIT_DEBUG
1819        printk(KERN_ERR
1820               "audit(:%d) pid=%d in syscall=%d;"
1821               " entering syscall=%d\n",
1822               context->serial, tsk->pid, context->major, major);
1823#endif
1824        newctx = audit_alloc_context(context->state);
1825        if (newctx) {
1826            newctx->previous = context;
1827            context = newctx;
1828            tsk->audit_context = newctx;
1829        } else {
1830            /* If we can't alloc a new context, the best we
1831             * can do is to leak memory (any pending putname
1832             * will be lost). The only other alternative is
1833             * to abandon auditing. */
1834            audit_zero_context(context, context->state);
1835        }
1836    }
1837    BUG_ON(context->in_syscall || context->name_count);
1838
1839    if (!audit_enabled)
1840        return;
1841
1842    context->arch = arch;
1843    context->major = major;
1844    context->argv[0] = a1;
1845    context->argv[1] = a2;
1846    context->argv[2] = a3;
1847    context->argv[3] = a4;
1848
1849    state = context->state;
1850    context->dummy = !audit_n_rules;
1851    if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
1852        context->prio = 0;
1853        state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1854    }
1855    if (state == AUDIT_DISABLED)
1856        return;
1857
1858    context->serial = 0;
1859    context->ctime = CURRENT_TIME;
1860    context->in_syscall = 1;
1861    context->current_state = state;
1862    context->ppid = 0;
1863}
1864
1865/**
1866 * audit_syscall_exit - deallocate audit context after a system call
1867 * @success: success value of the syscall
1868 * @return_code: return value of the syscall
1869 *
1870 * Tear down after system call. If the audit context has been marked as
1871 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1872 * filtering, or because some other part of the kernel wrote an audit
1873 * message), then write out the syscall information. In call cases,
1874 * free the names stored from getname().
1875 */
1876void __audit_syscall_exit(int success, long return_code)
1877{
1878    struct task_struct *tsk = current;
1879    struct audit_context *context;
1880
1881    if (success)
1882        success = AUDITSC_SUCCESS;
1883    else
1884        success = AUDITSC_FAILURE;
1885
1886    context = audit_get_context(tsk, success, return_code);
1887    if (!context)
1888        return;
1889
1890    if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1891        audit_log_exit(context, tsk);
1892
1893    context->in_syscall = 0;
1894    context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1895
1896    if (!list_empty(&context->killed_trees))
1897        audit_kill_trees(&context->killed_trees);
1898
1899    if (context->previous) {
1900        struct audit_context *new_context = context->previous;
1901        context->previous = NULL;
1902        audit_free_context(context);
1903        tsk->audit_context = new_context;
1904    } else {
1905        audit_free_names(context);
1906        unroll_tree_refs(context, NULL, 0);
1907        audit_free_aux(context);
1908        context->aux = NULL;
1909        context->aux_pids = NULL;
1910        context->target_pid = 0;
1911        context->target_sid = 0;
1912        context->sockaddr_len = 0;
1913        context->type = 0;
1914        context->fds[0] = -1;
1915        if (context->state != AUDIT_RECORD_CONTEXT) {
1916            kfree(context->filterkey);
1917            context->filterkey = NULL;
1918        }
1919        tsk->audit_context = context;
1920    }
1921}
1922
1923static inline void handle_one(const struct inode *inode)
1924{
1925#ifdef CONFIG_AUDIT_TREE
1926    struct audit_context *context;
1927    struct audit_tree_refs *p;
1928    struct audit_chunk *chunk;
1929    int count;
1930    if (likely(hlist_empty(&inode->i_fsnotify_marks)))
1931        return;
1932    context = current->audit_context;
1933    p = context->trees;
1934    count = context->tree_count;
1935    rcu_read_lock();
1936    chunk = audit_tree_lookup(inode);
1937    rcu_read_unlock();
1938    if (!chunk)
1939        return;
1940    if (likely(put_tree_ref(context, chunk)))
1941        return;
1942    if (unlikely(!grow_tree_refs(context))) {
1943        printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
1944        audit_set_auditable(context);
1945        audit_put_chunk(chunk);
1946        unroll_tree_refs(context, p, count);
1947        return;
1948    }
1949    put_tree_ref(context, chunk);
1950#endif
1951}
1952
1953static void handle_path(const struct dentry *dentry)
1954{
1955#ifdef CONFIG_AUDIT_TREE
1956    struct audit_context *context;
1957    struct audit_tree_refs *p;
1958    const struct dentry *d, *parent;
1959    struct audit_chunk *drop;
1960    unsigned long seq;
1961    int count;
1962
1963    context = current->audit_context;
1964    p = context->trees;
1965    count = context->tree_count;
1966retry:
1967    drop = NULL;
1968    d = dentry;
1969    rcu_read_lock();
1970    seq = read_seqbegin(&rename_lock);
1971    for(;;) {
1972        struct inode *inode = d->d_inode;
1973        if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
1974            struct audit_chunk *chunk;
1975            chunk = audit_tree_lookup(inode);
1976            if (chunk) {
1977                if (unlikely(!put_tree_ref(context, chunk))) {
1978                    drop = chunk;
1979                    break;
1980                }
1981            }
1982        }
1983        parent = d->d_parent;
1984        if (parent == d)
1985            break;
1986        d = parent;
1987    }
1988    if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */
1989        rcu_read_unlock();
1990        if (!drop) {
1991            /* just a race with rename */
1992            unroll_tree_refs(context, p, count);
1993            goto retry;
1994        }
1995        audit_put_chunk(drop);
1996        if (grow_tree_refs(context)) {
1997            /* OK, got more space */
1998            unroll_tree_refs(context, p, count);
1999            goto retry;
2000        }
2001        /* too bad */
2002        printk(KERN_WARNING
2003            "out of memory, audit has lost a tree reference\n");
2004        unroll_tree_refs(context, p, count);
2005        audit_set_auditable(context);
2006        return;
2007    }
2008    rcu_read_unlock();
2009#endif
2010}
2011
2012static struct audit_names *audit_alloc_name(struct audit_context *context)
2013{
2014    struct audit_names *aname;
2015
2016    if (context->name_count < AUDIT_NAMES) {
2017        aname = &context->preallocated_names[context->name_count];
2018        memset(aname, 0, sizeof(*aname));
2019    } else {
2020        aname = kzalloc(sizeof(*aname), GFP_NOFS);
2021        if (!aname)
2022            return NULL;
2023        aname->should_free = true;
2024    }
2025
2026    aname->ino = (unsigned long)-1;
2027    list_add_tail(&aname->list, &context->names_list);
2028
2029    context->name_count++;
2030#if AUDIT_DEBUG
2031    context->ino_count++;
2032#endif
2033    return aname;
2034}
2035
2036/**
2037 * audit_getname - add a name to the list
2038 * @name: name to add
2039 *
2040 * Add a name to the list of audit names for this context.
2041 * Called from fs/namei.c:getname().
2042 */
2043void __audit_getname(const char *name)
2044{
2045    struct audit_context *context = current->audit_context;
2046    struct audit_names *n;
2047
2048    if (!context->in_syscall) {
2049#if AUDIT_DEBUG == 2
2050        printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
2051               __FILE__, __LINE__, context->serial, name);
2052        dump_stack();
2053#endif
2054        return;
2055    }
2056
2057    n = audit_alloc_name(context);
2058    if (!n)
2059        return;
2060
2061    n->name = name;
2062    n->name_len = AUDIT_NAME_FULL;
2063    n->name_put = true;
2064
2065    if (!context->pwd.dentry)
2066        get_fs_pwd(current->fs, &context->pwd);
2067}
2068
2069/* audit_putname - intercept a putname request
2070 * @name: name to intercept and delay for putname
2071 *
2072 * If we have stored the name from getname in the audit context,
2073 * then we delay the putname until syscall exit.
2074 * Called from include/linux/fs.h:putname().
2075 */
2076void audit_putname(const char *name)
2077{
2078    struct audit_context *context = current->audit_context;
2079
2080    BUG_ON(!context);
2081    if (!context->in_syscall) {
2082#if AUDIT_DEBUG == 2
2083        printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
2084               __FILE__, __LINE__, context->serial, name);
2085        if (context->name_count) {
2086            struct audit_names *n;
2087            int i;
2088
2089            list_for_each_entry(n, &context->names_list, list)
2090                printk(KERN_ERR "name[%d] = %p = %s\n", i,
2091                       n->name, n->name ?: "(null)");
2092            }
2093#endif
2094        __putname(name);
2095    }
2096#if AUDIT_DEBUG
2097    else {
2098        ++context->put_count;
2099        if (context->put_count > context->name_count) {
2100            printk(KERN_ERR "%s:%d(:%d): major=%d"
2101                   " in_syscall=%d putname(%p) name_count=%d"
2102                   " put_count=%d\n",
2103                   __FILE__, __LINE__,
2104                   context->serial, context->major,
2105                   context->in_syscall, name, context->name_count,
2106                   context->put_count);
2107            dump_stack();
2108        }
2109    }
2110#endif
2111}
2112
2113static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry)
2114{
2115    struct cpu_vfs_cap_data caps;
2116    int rc;
2117
2118    if (!dentry)
2119        return 0;
2120
2121    rc = get_vfs_caps_from_disk(dentry, &caps);
2122    if (rc)
2123        return rc;
2124
2125    name->fcap.permitted = caps.permitted;
2126    name->fcap.inheritable = caps.inheritable;
2127    name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2128    name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2129
2130    return 0;
2131}
2132
2133
2134/* Copy inode data into an audit_names. */
2135static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
2136                 const struct inode *inode)
2137{
2138    name->ino = inode->i_ino;
2139    name->dev = inode->i_sb->s_dev;
2140    name->mode = inode->i_mode;
2141    name->uid = inode->i_uid;
2142    name->gid = inode->i_gid;
2143    name->rdev = inode->i_rdev;
2144    security_inode_getsecid(inode, &name->osid);
2145    audit_copy_fcaps(name, dentry);
2146}
2147
2148/**
2149 * audit_inode - store the inode and device from a lookup
2150 * @name: name being audited
2151 * @dentry: dentry being audited
2152 *
2153 * Called from fs/namei.c:path_lookup().
2154 */
2155void __audit_inode(const char *name, const struct dentry *dentry)
2156{
2157    struct audit_context *context = current->audit_context;
2158    const struct inode *inode = dentry->d_inode;
2159    struct audit_names *n;
2160
2161    if (!context->in_syscall)
2162        return;
2163
2164    list_for_each_entry_reverse(n, &context->names_list, list) {
2165        if (n->name && (n->name == name))
2166            goto out;
2167    }
2168
2169    /* unable to find the name from a previous getname() */
2170    n = audit_alloc_name(context);
2171    if (!n)
2172        return;
2173out:
2174    handle_path(dentry);
2175    audit_copy_inode(n, dentry, inode);
2176}
2177
2178/**
2179 * audit_inode_child - collect inode info for created/removed objects
2180 * @dentry: dentry being audited
2181 * @parent: inode of dentry parent
2182 *
2183 * For syscalls that create or remove filesystem objects, audit_inode
2184 * can only collect information for the filesystem object's parent.
2185 * This call updates the audit context with the child's information.
2186 * Syscalls that create a new filesystem object must be hooked after
2187 * the object is created. Syscalls that remove a filesystem object
2188 * must be hooked prior, in order to capture the target inode during
2189 * unsuccessful attempts.
2190 */
2191void __audit_inode_child(const struct dentry *dentry,
2192             const struct inode *parent)
2193{
2194    struct audit_context *context = current->audit_context;
2195    const char *found_parent = NULL, *found_child = NULL;
2196    const struct inode *inode = dentry->d_inode;
2197    const char *dname = dentry->d_name.name;
2198    struct audit_names *n;
2199    int dirlen = 0;
2200
2201    if (!context->in_syscall)
2202        return;
2203
2204    if (inode)
2205        handle_one(inode);
2206
2207    /* parent is more likely, look for it first */
2208    list_for_each_entry(n, &context->names_list, list) {
2209        if (!n->name)
2210            continue;
2211
2212        if (n->ino == parent->i_ino &&
2213            !audit_compare_dname_path(dname, n->name, &dirlen)) {
2214            n->name_len = dirlen; /* update parent data in place */
2215            found_parent = n->name;
2216            goto add_names;
2217        }
2218    }
2219
2220    /* no matching parent, look for matching child */
2221    list_for_each_entry(n, &context->names_list, list) {
2222        if (!n->name)
2223            continue;
2224
2225        /* strcmp() is the more likely scenario */
2226        if (!strcmp(dname, n->name) ||
2227             !audit_compare_dname_path(dname, n->name, &dirlen)) {
2228            if (inode)
2229                audit_copy_inode(n, NULL, inode);
2230            else
2231                n->ino = (unsigned long)-1;
2232            found_child = n->name;
2233            goto add_names;
2234        }
2235    }
2236
2237add_names:
2238    if (!found_parent) {
2239        n = audit_alloc_name(context);
2240        if (!n)
2241            return;
2242        audit_copy_inode(n, NULL, parent);
2243    }
2244
2245    if (!found_child) {
2246        n = audit_alloc_name(context);
2247        if (!n)
2248            return;
2249
2250        /* Re-use the name belonging to the slot for a matching parent
2251         * directory. All names for this context are relinquished in
2252         * audit_free_names() */
2253        if (found_parent) {
2254            n->name = found_parent;
2255            n->name_len = AUDIT_NAME_FULL;
2256            /* don't call __putname() */
2257            n->name_put = false;
2258        }
2259
2260        if (inode)
2261            audit_copy_inode(n, NULL, inode);
2262    }
2263}
2264EXPORT_SYMBOL_GPL(__audit_inode_child);
2265
2266/**
2267 * auditsc_get_stamp - get local copies of audit_context values
2268 * @ctx: audit_context for the task
2269 * @t: timespec to store time recorded in the audit_context
2270 * @serial: serial value that is recorded in the audit_context
2271 *
2272 * Also sets the context as auditable.
2273 */
2274int auditsc_get_stamp(struct audit_context *ctx,
2275               struct timespec *t, unsigned int *serial)
2276{
2277    if (!ctx->in_syscall)
2278        return 0;
2279    if (!ctx->serial)
2280        ctx->serial = audit_serial();
2281    t->tv_sec = ctx->ctime.tv_sec;
2282    t->tv_nsec = ctx->ctime.tv_nsec;
2283    *serial = ctx->serial;
2284    if (!ctx->prio) {
2285        ctx->prio = 1;
2286        ctx->current_state = AUDIT_RECORD_CONTEXT;
2287    }
2288    return 1;
2289}
2290
2291/* global counter which is incremented every time something logs in */
2292static atomic_t session_id = ATOMIC_INIT(0);
2293
2294/**
2295 * audit_set_loginuid - set current task's audit_context loginuid
2296 * @loginuid: loginuid value
2297 *
2298 * Returns 0.
2299 *
2300 * Called (set) from fs/proc/base.c::proc_loginuid_write().
2301 */
2302int audit_set_loginuid(uid_t loginuid)
2303{
2304    struct task_struct *task = current;
2305    struct audit_context *context = task->audit_context;
2306    unsigned int sessionid;
2307
2308#ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE
2309    if (task->loginuid != -1)
2310        return -EPERM;
2311#else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
2312    if (!capable(CAP_AUDIT_CONTROL))
2313        return -EPERM;
2314#endif /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
2315
2316    sessionid = atomic_inc_return(&session_id);
2317    if (context && context->in_syscall) {
2318        struct audit_buffer *ab;
2319
2320        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
2321        if (ab) {
2322            audit_log_format(ab, "login pid=%d uid=%u "
2323                "old auid=%u new auid=%u"
2324                " old ses=%u new ses=%u",
2325                task->pid, task_uid(task),
2326                task->loginuid, loginuid,
2327                task->sessionid, sessionid);
2328            audit_log_end(ab);
2329        }
2330    }
2331    task->sessionid = sessionid;
2332    task->loginuid = loginuid;
2333    return 0;
2334}
2335
2336/**
2337 * __audit_mq_open - record audit data for a POSIX MQ open
2338 * @oflag: open flag
2339 * @mode: mode bits
2340 * @attr: queue attributes
2341 *
2342 */
2343void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2344{
2345    struct audit_context *context = current->audit_context;
2346
2347    if (attr)
2348        memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2349    else
2350        memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2351
2352    context->mq_open.oflag = oflag;
2353    context->mq_open.mode = mode;
2354
2355    context->type = AUDIT_MQ_OPEN;
2356}
2357
2358/**
2359 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2360 * @mqdes: MQ descriptor
2361 * @msg_len: Message length
2362 * @msg_prio: Message priority
2363 * @abs_timeout: Message timeout in absolute time
2364 *
2365 */
2366void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2367            const struct timespec *abs_timeout)
2368{
2369    struct audit_context *context = current->audit_context;
2370    struct timespec *p = &context->mq_sendrecv.abs_timeout;
2371
2372    if (abs_timeout)
2373        memcpy(p, abs_timeout, sizeof(struct timespec));
2374    else
2375        memset(p, 0, sizeof(struct timespec));
2376
2377    context->mq_sendrecv.mqdes = mqdes;
2378    context->mq_sendrecv.msg_len = msg_len;
2379    context->mq_sendrecv.msg_prio = msg_prio;
2380
2381    context->type = AUDIT_MQ_SENDRECV;
2382}
2383
2384/**
2385 * __audit_mq_notify - record audit data for a POSIX MQ notify
2386 * @mqdes: MQ descriptor
2387 * @notification: Notification event
2388 *
2389 */
2390
2391void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2392{
2393    struct audit_context *context = current->audit_context;
2394
2395    if (notification)
2396        context->mq_notify.sigev_signo = notification->sigev_signo;
2397    else
2398        context->mq_notify.sigev_signo = 0;
2399
2400    context->mq_notify.mqdes = mqdes;
2401    context->type = AUDIT_MQ_NOTIFY;
2402}
2403
2404/**
2405 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2406 * @mqdes: MQ descriptor
2407 * @mqstat: MQ flags
2408 *
2409 */
2410void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2411{
2412    struct audit_context *context = current->audit_context;
2413    context->mq_getsetattr.mqdes = mqdes;
2414    context->mq_getsetattr.mqstat = *mqstat;
2415    context->type = AUDIT_MQ_GETSETATTR;
2416}
2417
2418/**
2419 * audit_ipc_obj - record audit data for ipc object
2420 * @ipcp: ipc permissions
2421 *
2422 */
2423void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2424{
2425    struct audit_context *context = current->audit_context;
2426    context->ipc.uid = ipcp->uid;
2427    context->ipc.gid = ipcp->gid;
2428    context->ipc.mode = ipcp->mode;
2429    context->ipc.has_perm = 0;
2430    security_ipc_getsecid(ipcp, &context->ipc.osid);
2431    context->type = AUDIT_IPC;
2432}
2433
2434/**
2435 * audit_ipc_set_perm - record audit data for new ipc permissions
2436 * @qbytes: msgq bytes
2437 * @uid: msgq user id
2438 * @gid: msgq group id
2439 * @mode: msgq mode (permissions)
2440 *
2441 * Called only after audit_ipc_obj().
2442 */
2443void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
2444{
2445    struct audit_context *context = current->audit_context;
2446
2447    context->ipc.qbytes = qbytes;
2448    context->ipc.perm_uid = uid;
2449    context->ipc.perm_gid = gid;
2450    context->ipc.perm_mode = mode;
2451    context->ipc.has_perm = 1;
2452}
2453
2454int __audit_bprm(struct linux_binprm *bprm)
2455{
2456    struct audit_aux_data_execve *ax;
2457    struct audit_context *context = current->audit_context;
2458
2459    ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2460    if (!ax)
2461        return -ENOMEM;
2462
2463    ax->argc = bprm->argc;
2464    ax->envc = bprm->envc;
2465    ax->mm = bprm->mm;
2466    ax->d.type = AUDIT_EXECVE;
2467    ax->d.next = context->aux;
2468    context->aux = (void *)ax;
2469    return 0;
2470}
2471
2472
2473/**
2474 * audit_socketcall - record audit data for sys_socketcall
2475 * @nargs: number of args
2476 * @args: args array
2477 *
2478 */
2479void __audit_socketcall(int nargs, unsigned long *args)
2480{
2481    struct audit_context *context = current->audit_context;
2482
2483    context->type = AUDIT_SOCKETCALL;
2484    context->socketcall.nargs = nargs;
2485    memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2486}
2487
2488/**
2489 * __audit_fd_pair - record audit data for pipe and socketpair
2490 * @fd1: the first file descriptor
2491 * @fd2: the second file descriptor
2492 *
2493 */
2494void __audit_fd_pair(int fd1, int fd2)
2495{
2496    struct audit_context *context = current->audit_context;
2497    context->fds[0] = fd1;
2498    context->fds[1] = fd2;
2499}
2500
2501/**
2502 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2503 * @len: data length in user space
2504 * @a: data address in kernel space
2505 *
2506 * Returns 0 for success or NULL context or < 0 on error.
2507 */
2508int __audit_sockaddr(int len, void *a)
2509{
2510    struct audit_context *context = current->audit_context;
2511
2512    if (!context->sockaddr) {
2513        void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2514        if (!p)
2515            return -ENOMEM;
2516        context->sockaddr = p;
2517    }
2518
2519    context->sockaddr_len = len;
2520    memcpy(context->sockaddr, a, len);
2521    return 0;
2522}
2523
2524void __audit_ptrace(struct task_struct *t)
2525{
2526    struct audit_context *context = current->audit_context;
2527
2528    context->target_pid = t->pid;
2529    context->target_auid = audit_get_loginuid(t);
2530    context->target_uid = task_uid(t);
2531    context->target_sessionid = audit_get_sessionid(t);
2532    security_task_getsecid(t, &context->target_sid);
2533    memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2534}
2535
2536/**
2537 * audit_signal_info - record signal info for shutting down audit subsystem
2538 * @sig: signal value
2539 * @t: task being signaled
2540 *
2541 * If the audit subsystem is being terminated, record the task (pid)
2542 * and uid that is doing that.
2543 */
2544int __audit_signal_info(int sig, struct task_struct *t)
2545{
2546    struct audit_aux_data_pids *axp;
2547    struct task_struct *tsk = current;
2548    struct audit_context *ctx = tsk->audit_context;
2549    uid_t uid = current_uid(), t_uid = task_uid(t);
2550
2551    if (audit_pid && t->tgid == audit_pid) {
2552        if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
2553            audit_sig_pid = tsk->pid;
2554            if (tsk->loginuid != -1)
2555                audit_sig_uid = tsk->loginuid;
2556            else
2557                audit_sig_uid = uid;
2558            security_task_getsecid(tsk, &audit_sig_sid);
2559        }
2560        if (!audit_signals || audit_dummy_context())
2561            return 0;
2562    }
2563
2564    /* optimize the common case by putting first signal recipient directly
2565     * in audit_context */
2566    if (!ctx->target_pid) {
2567        ctx->target_pid = t->tgid;
2568        ctx->target_auid = audit_get_loginuid(t);
2569        ctx->target_uid = t_uid;
2570        ctx->target_sessionid = audit_get_sessionid(t);
2571        security_task_getsecid(t, &ctx->target_sid);
2572        memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2573        return 0;
2574    }
2575
2576    axp = (void *)ctx->aux_pids;
2577    if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2578        axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2579        if (!axp)
2580            return -ENOMEM;
2581
2582        axp->d.type = AUDIT_OBJ_PID;
2583        axp->d.next = ctx->aux_pids;
2584        ctx->aux_pids = (void *)axp;
2585    }
2586    BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2587
2588    axp->target_pid[axp->pid_count] = t->tgid;
2589    axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2590    axp->target_uid[axp->pid_count] = t_uid;
2591    axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2592    security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2593    memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2594    axp->pid_count++;
2595
2596    return 0;
2597}
2598
2599/**
2600 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2601 * @bprm: pointer to the bprm being processed
2602 * @new: the proposed new credentials
2603 * @old: the old credentials
2604 *
2605 * Simply check if the proc already has the caps given by the file and if not
2606 * store the priv escalation info for later auditing at the end of the syscall
2607 *
2608 * -Eric
2609 */
2610int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2611               const struct cred *new, const struct cred *old)
2612{
2613    struct audit_aux_data_bprm_fcaps *ax;
2614    struct audit_context *context = current->audit_context;
2615    struct cpu_vfs_cap_data vcaps;
2616    struct dentry *dentry;
2617
2618    ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2619    if (!ax)
2620        return -ENOMEM;
2621
2622    ax->d.type = AUDIT_BPRM_FCAPS;
2623    ax->d.next = context->aux;
2624    context->aux = (void *)ax;
2625
2626    dentry = dget(bprm->file->f_dentry);
2627    get_vfs_caps_from_disk(dentry, &vcaps);
2628    dput(dentry);
2629
2630    ax->fcap.permitted = vcaps.permitted;
2631    ax->fcap.inheritable = vcaps.inheritable;
2632    ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2633    ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2634
2635    ax->old_pcap.permitted = old->cap_permitted;
2636    ax->old_pcap.inheritable = old->cap_inheritable;
2637    ax->old_pcap.effective = old->cap_effective;
2638
2639    ax->new_pcap.permitted = new->cap_permitted;
2640    ax->new_pcap.inheritable = new->cap_inheritable;
2641    ax->new_pcap.effective = new->cap_effective;
2642    return 0;
2643}
2644
2645/**
2646 * __audit_log_capset - store information about the arguments to the capset syscall
2647 * @pid: target pid of the capset call
2648 * @new: the new credentials
2649 * @old: the old (current) credentials
2650 *
2651 * Record the aguments userspace sent to sys_capset for later printing by the
2652 * audit system if applicable
2653 */
2654void __audit_log_capset(pid_t pid,
2655               const struct cred *new, const struct cred *old)
2656{
2657    struct audit_context *context = current->audit_context;
2658    context->capset.pid = pid;
2659    context->capset.cap.effective = new->cap_effective;
2660    context->capset.cap.inheritable = new->cap_effective;
2661    context->capset.cap.permitted = new->cap_permitted;
2662    context->type = AUDIT_CAPSET;
2663}
2664
2665void __audit_mmap_fd(int fd, int flags)
2666{
2667    struct audit_context *context = current->audit_context;
2668    context->mmap.fd = fd;
2669    context->mmap.flags = flags;
2670    context->type = AUDIT_MMAP;
2671}
2672
2673static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
2674{
2675    uid_t auid, uid;
2676    gid_t gid;
2677    unsigned int sessionid;
2678
2679    auid = audit_get_loginuid(current);
2680    sessionid = audit_get_sessionid(current);
2681    current_uid_gid(&uid, &gid);
2682
2683    audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2684             auid, uid, gid, sessionid);
2685    audit_log_task_context(ab);
2686    audit_log_format(ab, " pid=%d comm=", current->pid);
2687    audit_log_untrustedstring(ab, current->comm);
2688    audit_log_format(ab, " reason=");
2689    audit_log_string(ab, reason);
2690    audit_log_format(ab, " sig=%ld", signr);
2691}
2692/**
2693 * audit_core_dumps - record information about processes that end abnormally
2694 * @signr: signal value
2695 *
2696 * If a process ends with a core dump, something fishy is going on and we
2697 * should record the event for investigation.
2698 */
2699void audit_core_dumps(long signr)
2700{
2701    struct audit_buffer *ab;
2702
2703    if (!audit_enabled)
2704        return;
2705
2706    if (signr == SIGQUIT) /* don't care for those */
2707        return;
2708
2709    ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2710    audit_log_abend(ab, "memory violation", signr);
2711    audit_log_end(ab);
2712}
2713
2714void __audit_seccomp(unsigned long syscall, long signr, int code)
2715{
2716    struct audit_buffer *ab;
2717
2718    ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2719    audit_log_abend(ab, "seccomp", signr);
2720    audit_log_format(ab, " syscall=%ld", syscall);
2721    audit_log_format(ab, " compat=%d", is_compat_task());
2722    audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current));
2723    audit_log_format(ab, " code=0x%x", code);
2724    audit_log_end(ab);
2725}
2726
2727struct list_head *audit_killed_trees(void)
2728{
2729    struct audit_context *ctx = current->audit_context;
2730    if (likely(!ctx || !ctx->in_syscall))
2731        return NULL;
2732    return &ctx->killed_trees;
2733}
2734

Archive Download this file



interactive