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auditsc.c
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/* auditsc.c -- System-call auditing support
* Handles all system-call specific auditing features.
*
* Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
* Copyright (C) 2005 IBM Corporation
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Written by Rickard E. (Rik) Faith <faith@redhat.com>
*
* Many of the ideas implemented here are from Stephen C. Tweedie,
* especially the idea of avoiding a copy by using getname.
*
* The method for actual interception of syscall entry and exit (not in
* this file -- see entry.S) is based on a GPL'd patch written by
* okir@suse.de and Copyright 2003 SuSE Linux AG.
*
* The support of additional filter rules compares (>, <, >=, <=) was
* added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
*
*/
#include <linux/init.h>
#include <asm/types.h>
#include <asm/atomic.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/mount.h>
#include <linux/socket.h>
#include <linux/audit.h>
#include <linux/personality.h>
#include <linux/time.h>
#include <linux/kthread.h>
#include <linux/netlink.h>
#include <linux/compiler.h>
#include <asm/unistd.h>
/* 0 = no checking
1 = put_count checking
2 = verbose put_count checking
*/
#define AUDIT_DEBUG 0
/* No syscall auditing will take place unless audit_enabled != 0. */
extern int audit_enabled;
/* AUDIT_NAMES is the number of slots we reserve in the audit_context
* for saving names from getname(). */
#define AUDIT_NAMES 20
/* AUDIT_NAMES_RESERVED is the number of slots we reserve in the
* audit_context from being used for nameless inodes from
* path_lookup. */
#define AUDIT_NAMES_RESERVED 7
/* At task start time, the audit_state is set in the audit_context using
a per-task filter. At syscall entry, the audit_state is augmented by
the syscall filter. */
enum audit_state {
AUDIT_DISABLED, /* Do not create per-task audit_context.
* No syscall-specific audit records can
* be generated. */
AUDIT_SETUP_CONTEXT, /* Create the per-task audit_context,
* but don't necessarily fill it in at
* syscall entry time (i.e., filter
* instead). */
AUDIT_BUILD_CONTEXT, /* Create the per-task audit_context,
* and always fill it in at syscall
* entry time. This makes a full
* syscall record available if some
* other part of the kernel decides it
* should be recorded. */
AUDIT_RECORD_CONTEXT /* Create the per-task audit_context,
* always fill it in at syscall entry
* time, and always write out the audit
* record at syscall exit time. */
};
/* When fs/namei.c:getname() is called, we store the pointer in name and
* we don't let putname() free it (instead we free all of the saved
* pointers at syscall exit time).
*
* Further, in fs/namei.c:path_lookup() we store the inode and device. */
struct audit_names {
const char *name;
unsigned long ino;
dev_t dev;
umode_t mode;
uid_t uid;
gid_t gid;
dev_t rdev;
unsigned flags;
};
struct audit_aux_data {
struct audit_aux_data *next;
int type;
};
#define AUDIT_AUX_IPCPERM 0
struct audit_aux_data_ipcctl {
struct audit_aux_data d;
struct ipc_perm p;
unsigned long qbytes;
uid_t uid;
gid_t gid;
mode_t mode;
};
struct audit_aux_data_socketcall {
struct audit_aux_data d;
int nargs;
unsigned long args[0];
};
struct audit_aux_data_sockaddr {
struct audit_aux_data d;
int len;
char a[0];
};
struct audit_aux_data_path {
struct audit_aux_data d;
struct dentry *dentry;
struct vfsmount *mnt;
};
/* The per-task audit context. */
struct audit_context {
int in_syscall; /* 1 if task is in a syscall */
enum audit_state state;
unsigned int serial; /* serial number for record */
struct timespec ctime; /* time of syscall entry */
uid_t loginuid; /* login uid (identity) */
int major; /* syscall number */
unsigned long argv[4]; /* syscall arguments */
int return_valid; /* return code is valid */
long return_code;/* syscall return code */
int auditable; /* 1 if record should be written */
int name_count;
struct audit_names names[AUDIT_NAMES];
struct dentry * pwd;
struct vfsmount * pwdmnt;
struct audit_context *previous; /* For nested syscalls */
struct audit_aux_data *aux;
/* Save things to print about task_struct */
pid_t pid;
uid_t uid, euid, suid, fsuid;
gid_t gid, egid, sgid, fsgid;
unsigned long personality;
int arch;
#if AUDIT_DEBUG
int put_count;
int ino_count;
#endif
};
/* Public API */
/* There are three lists of rules -- one to search at task creation
* time, one to search at syscall entry time, and another to search at
* syscall exit time. */
static struct list_head audit_filter_list[AUDIT_NR_FILTERS] = {
LIST_HEAD_INIT(audit_filter_list[0]),
LIST_HEAD_INIT(audit_filter_list[1]),
LIST_HEAD_INIT(audit_filter_list[2]),
LIST_HEAD_INIT(audit_filter_list[3]),
LIST_HEAD_INIT(audit_filter_list[4]),
#if AUDIT_NR_FILTERS != 5
#error Fix audit_filter_list initialiser
#endif
};
struct audit_entry {
struct list_head list;
struct rcu_head rcu;
struct audit_rule rule;
};
extern int audit_pid;
/* Copy rule from user-space to kernel-space. Called from
* audit_add_rule during AUDIT_ADD. */
static inline int audit_copy_rule(struct audit_rule *d, struct audit_rule *s)
{
int i;
if (s->action != AUDIT_NEVER
&& s->action != AUDIT_POSSIBLE
&& s->action != AUDIT_ALWAYS)
return -1;
if (s->field_count < 0 || s->field_count > AUDIT_MAX_FIELDS)
return -1;
if ((s->flags & ~AUDIT_FILTER_PREPEND) >= AUDIT_NR_FILTERS)
return -1;
d->flags = s->flags;
d->action = s->action;
d->field_count = s->field_count;
for (i = 0; i < d->field_count; i++) {
d->fields[i] = s->fields[i];
d->values[i] = s->values[i];
}
for (i = 0; i < AUDIT_BITMASK_SIZE; i++) d->mask[i] = s->mask[i];
return 0;
}
/* Check to see if two rules are identical. It is called from
* audit_add_rule during AUDIT_ADD and
* audit_del_rule during AUDIT_DEL. */
static inline int audit_compare_rule(struct audit_rule *a, struct audit_rule *b)
{
int i;
if (a->flags != b->flags)
return 1;
if (a->action != b->action)
return 1;
if (a->field_count != b->field_count)
return 1;
for (i = 0; i < a->field_count; i++) {
if (a->fields[i] != b->fields[i]
|| a->values[i] != b->values[i])
return 1;
}
for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
if (a->mask[i] != b->mask[i])
return 1;
return 0;
}
/* Note that audit_add_rule and audit_del_rule are called via
* audit_receive() in audit.c, and are protected by
* audit_netlink_sem. */
static inline int audit_add_rule(struct audit_rule *rule,
struct list_head *list)
{
struct audit_entry *entry;
int i;
/* Do not use the _rcu iterator here, since this is the only
* addition routine. */
list_for_each_entry(entry, list, list) {
if (!audit_compare_rule(rule, &entry->rule)) {
return -EEXIST;
}
}
for (i = 0; i < rule->field_count; i++) {
if (rule->fields[i] & AUDIT_UNUSED_BITS)
return -EINVAL;
if ( rule->fields[i] & AUDIT_NEGATE )
rule->fields[i] |= AUDIT_NOT_EQUAL;
else if ( (rule->fields[i] & AUDIT_OPERATORS) == 0 )
rule->fields[i] |= AUDIT_EQUAL;
rule->fields[i] &= (~AUDIT_NEGATE);
}
if (!(entry = kmalloc(sizeof(*entry), GFP_KERNEL)))
return -ENOMEM;
if (audit_copy_rule(&entry->rule, rule)) {
kfree(entry);
return -EINVAL;
}
if (entry->rule.flags & AUDIT_FILTER_PREPEND) {
entry->rule.flags &= ~AUDIT_FILTER_PREPEND;
list_add_rcu(&entry->list, list);
} else {
list_add_tail_rcu(&entry->list, list);
}
return 0;
}
static inline void audit_free_rule(struct rcu_head *head)
{
struct audit_entry *e = container_of(head, struct audit_entry, rcu);
kfree(e);
}
/* Note that audit_add_rule and audit_del_rule are called via
* audit_receive() in audit.c, and are protected by
* audit_netlink_sem. */
static inline int audit_del_rule(struct audit_rule *rule,
struct list_head *list)
{
struct audit_entry *e;
/* Do not use the _rcu iterator here, since this is the only
* deletion routine. */
list_for_each_entry(e, list, list) {
if (!audit_compare_rule(rule, &e->rule)) {
list_del_rcu(&e->list);
call_rcu(&e->rcu, audit_free_rule);
return 0;
}
}
return -ENOENT; /* No matching rule */
}
static int audit_list_rules(void *_dest)
{
int pid, seq;
int *dest = _dest;
struct audit_entry *entry;
int i;
pid = dest[0];
seq = dest[1];
kfree(dest);
down(&audit_netlink_sem);
/* The *_rcu iterators not needed here because we are
always called with audit_netlink_sem held. */
for (i=0; i<AUDIT_NR_FILTERS; i++) {
list_for_each_entry(entry, &audit_filter_list[i], list)
audit_send_reply(pid, seq, AUDIT_LIST, 0, 1,
&entry->rule, sizeof(entry->rule));
}
audit_send_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0);
up(&audit_netlink_sem);
return 0;
}
/**
* audit_receive_filter - apply all rules to the specified message type
* @type: audit message type
* @pid: target pid for netlink audit messages
* @uid: target uid for netlink audit messages
* @seq: netlink audit message sequence (serial) number
* @data: payload data
* @loginuid: loginuid of sender
*/
int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
uid_t loginuid)
{
struct task_struct *tsk;
int *dest;
int err = 0;
unsigned listnr;
switch (type) {
case AUDIT_LIST:
/* We can't just spew out the rules here because we might fill
* the available socket buffer space and deadlock waiting for
* auditctl to read from it... which isn't ever going to
* happen if we're actually running in the context of auditctl
* trying to _send_ the stuff */
dest = kmalloc(2 * sizeof(int), GFP_KERNEL);
if (!dest)
return -ENOMEM;
dest[0] = pid;
dest[1] = seq;
tsk = kthread_run(audit_list_rules, dest, "audit_list_rules");
if (IS_ERR(tsk)) {
kfree(dest);
err = PTR_ERR(tsk);
}
break;
case AUDIT_ADD:
listnr =((struct audit_rule *)data)->flags & ~AUDIT_FILTER_PREPEND;
if (listnr >= AUDIT_NR_FILTERS)
return -EINVAL;
err = audit_add_rule(data, &audit_filter_list[listnr]);
if (!err)
audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
"auid=%u added an audit rule\n", loginuid);
break;
case AUDIT_DEL:
listnr =((struct audit_rule *)data)->flags & ~AUDIT_FILTER_PREPEND;
if (listnr >= AUDIT_NR_FILTERS)
return -EINVAL;
err = audit_del_rule(data, &audit_filter_list[listnr]);
if (!err)
audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
"auid=%u removed an audit rule\n", loginuid);
break;
default:
return -EINVAL;
}
return err;
}
static int audit_comparator(const u32 left, const u32 op, const u32 right)
{
switch (op) {
case AUDIT_EQUAL:
return (left == right);
case AUDIT_NOT_EQUAL:
return (left != right);
case AUDIT_LESS_THAN:
return (left < right);
case AUDIT_LESS_THAN_OR_EQUAL:
return (left <= right);
case AUDIT_GREATER_THAN:
return (left > right);
case AUDIT_GREATER_THAN_OR_EQUAL:
return (left >= right);
default:
return -EINVAL;
}
}
/* Compare a task_struct with an audit_rule. Return 1 on match, 0
* otherwise. */
static int audit_filter_rules(struct task_struct *tsk,
struct audit_rule *rule,
struct audit_context *ctx,
enum audit_state *state)
{
int i, j;
for (i = 0; i < rule->field_count; i++) {
u32 field = rule->fields[i] & ~AUDIT_OPERATORS;
u32 op = rule->fields[i] & AUDIT_OPERATORS;
u32 value = rule->values[i];
int result = 0;
switch (field) {
case AUDIT_PID:
result = audit_comparator(tsk->pid, op, value);
break;
case AUDIT_UID:
result = audit_comparator(tsk->uid, op, value);
break;
case AUDIT_EUID:
result = audit_comparator(tsk->euid, op, value);
break;
case AUDIT_SUID:
result = audit_comparator(tsk->suid, op, value);
break;
case AUDIT_FSUID:
result = audit_comparator(tsk->fsuid, op, value);
break;
case AUDIT_GID:
result = audit_comparator(tsk->gid, op, value);
break;
case AUDIT_EGID:
result = audit_comparator(tsk->egid, op, value);
break;
case AUDIT_SGID:
result = audit_comparator(tsk->sgid, op, value);
break;
case AUDIT_FSGID:
result = audit_comparator(tsk->fsgid, op, value);
break;
case AUDIT_PERS:
result = audit_comparator(tsk->personality, op, value);
break;
case AUDIT_ARCH:
if (ctx)
result = audit_comparator(ctx->arch, op, value);
break;
case AUDIT_EXIT:
if (ctx && ctx->return_valid)
result = audit_comparator(ctx->return_code, op, value);
break;
case AUDIT_SUCCESS:
if (ctx && ctx->return_valid) {
if (value)
result = audit_comparator(ctx->return_valid, op, AUDITSC_SUCCESS);
else
result = audit_comparator(ctx->return_valid, op, AUDITSC_FAILURE);
}
break;
case AUDIT_DEVMAJOR:
if (ctx) {
for (j = 0; j < ctx->name_count; j++) {
if (audit_comparator(MAJOR(ctx->names[j].dev), op, value)) {
++result;
break;
}
}
}
break;
case AUDIT_DEVMINOR:
if (ctx) {
for (j = 0; j < ctx->name_count; j++) {
if (audit_comparator(MINOR(ctx->names[j].dev), op, value)) {
++result;
break;
}
}
}
break;
case AUDIT_INODE:
if (ctx) {
for (j = 0; j < ctx->name_count; j++) {
if ( audit_comparator(ctx->names[j].ino, op, value)) {
++result;
break;
}
}
}
break;
case AUDIT_LOGINUID:
result = 0;
if (ctx)
result = audit_comparator(ctx->loginuid, op, value);
break;
case AUDIT_ARG0:
case AUDIT_ARG1:
case AUDIT_ARG2:
case AUDIT_ARG3:
if (ctx)
result = audit_comparator(ctx->argv[field-AUDIT_ARG0], op, value);
break;
}
if (!result)
return 0;
}
switch (rule->action) {
case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
case AUDIT_POSSIBLE: *state = AUDIT_BUILD_CONTEXT; break;
case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
}
return 1;
}
/* At process creation time, we can determine if system-call auditing is
* completely disabled for this task. Since we only have the task
* structure at this point, we can only check uid and gid.
*/
static enum audit_state audit_filter_task(struct task_struct *tsk)
{
struct audit_entry *e;
enum audit_state state;
rcu_read_lock();
list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
if (audit_filter_rules(tsk, &e->rule, NULL, &state)) {
rcu_read_unlock();
return state;
}
}
rcu_read_unlock();
return AUDIT_BUILD_CONTEXT;
}
/* At syscall entry and exit time, this filter is called if the
* audit_state is not low enough that auditing cannot take place, but is
* also not high enough that we already know we have to write an audit
* record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
*/
static enum audit_state audit_filter_syscall(struct task_struct *tsk,
struct audit_context *ctx,
struct list_head *list)
{
struct audit_entry *e;
enum audit_state state;
if (audit_pid && tsk->tgid == audit_pid)
return AUDIT_DISABLED;
rcu_read_lock();
if (!list_empty(list)) {
int word = AUDIT_WORD(ctx->major);
int bit = AUDIT_BIT(ctx->major);
list_for_each_entry_rcu(e, list, list) {
if ((e->rule.mask[word] & bit) == bit
&& audit_filter_rules(tsk, &e->rule, ctx, &state)) {
rcu_read_unlock();
return state;
}
}
}
rcu_read_unlock();
return AUDIT_BUILD_CONTEXT;
}
static int audit_filter_user_rules(struct netlink_skb_parms *cb,
struct audit_rule *rule,
enum audit_state *state)
{
int i;
for (i = 0; i < rule->field_count; i++) {
u32 field = rule->fields[i] & ~AUDIT_OPERATORS;
u32 op = rule->fields[i] & AUDIT_OPERATORS;
u32 value = rule->values[i];
int result = 0;
switch (field) {
case AUDIT_PID:
result = audit_comparator(cb->creds.pid, op, value);
break;
case AUDIT_UID:
result = audit_comparator(cb->creds.uid, op, value);
break;
case AUDIT_GID:
result = audit_comparator(cb->creds.gid, op, value);
break;
case AUDIT_LOGINUID:
result = audit_comparator(cb->loginuid, op, value);
break;
}
if (!result)
return 0;
}
switch (rule->action) {
case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
case AUDIT_POSSIBLE: *state = AUDIT_BUILD_CONTEXT; break;
case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
}
return 1;
}
int audit_filter_user(struct netlink_skb_parms *cb, int type)
{
struct audit_entry *e;
enum audit_state state;
int ret = 1;
rcu_read_lock();
list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) {
if (audit_filter_user_rules(cb, &e->rule, &state)) {
if (state == AUDIT_DISABLED)
ret = 0;
break;
}
}
rcu_read_unlock();
return ret; /* Audit by default */
}
/* This should be called with task_lock() held. */
static inline struct audit_context *audit_get_context(struct task_struct *tsk,
int return_valid,
int return_code)
{
struct audit_context *context = tsk->audit_context;
if (likely(!context))
return NULL;
context->return_valid = return_valid;
context->return_code = return_code;
if (context->in_syscall && !context->auditable) {
enum audit_state state;
state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
if (state == AUDIT_RECORD_CONTEXT)
context->auditable = 1;
}
context->pid = tsk->pid;
context->uid = tsk->uid;
context->gid = tsk->gid;
context->euid = tsk->euid;
context->suid = tsk->suid;
context->fsuid = tsk->fsuid;
context->egid = tsk->egid;
context->sgid = tsk->sgid;
context->fsgid = tsk->fsgid;
context->personality = tsk->personality;
tsk->audit_context = NULL;
return context;
}
static inline void audit_free_names(struct audit_context *context)
{
int i;
#if AUDIT_DEBUG == 2
if (context->auditable
||context->put_count + context->ino_count != context->name_count) {
printk(KERN_ERR "audit.c:%d(:%d): major=%d in_syscall=%d"
" name_count=%d put_count=%d"
" ino_count=%d [NOT freeing]\n",
__LINE__,
context->serial, context->major, context->in_syscall,
context->name_count, context->put_count,
context->ino_count);
for (i = 0; i < context->name_count; i++)
printk(KERN_ERR "names[%d] = %p = %s\n", i,
context->names[i].name,
context->names[i].name);
dump_stack();
return;
}
#endif
#if AUDIT_DEBUG
context->put_count = 0;
context->ino_count = 0;
#endif
for (i = 0; i < context->name_count; i++)
if (context->names[i].name)
__putname(context->names[i].name);
context->name_count = 0;
if (context->pwd)
dput(context->pwd);
if (context->pwdmnt)
mntput(context->pwdmnt);
context->pwd = NULL;
context->pwdmnt = NULL;
}
static inline void audit_free_aux(struct audit_context *context)
{
struct audit_aux_data *aux;
while ((aux = context->aux)) {
if (aux->type == AUDIT_AVC_PATH) {
struct audit_aux_data_path *axi = (void *)aux;
dput(axi->dentry);
mntput(axi->mnt);
}
context->aux = aux->next;
kfree(aux);
}
}
static inline void audit_zero_context(struct audit_context *context,
enum audit_state state)
{
uid_t loginuid = context->loginuid;
memset(context, 0, sizeof(*context));
context->state = state;
context->loginuid = loginuid;
}
static inline struct audit_context *audit_alloc_context(enum audit_state state)
{
struct audit_context *context;
if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
return NULL;
audit_zero_context(context, state);
return context;
}
/**
* audit_alloc - allocate an audit context block for a task
* @tsk: task
*
* Filter on the task information and allocate a per-task audit context
* if necessary. Doing so turns on system call auditing for the
* specified task. This is called from copy_process, so no lock is
* needed.
*/
int audit_alloc(struct task_struct *tsk)
{
struct audit_context *context;
enum audit_state state;
if (likely(!audit_enabled))
return 0; /* Return if not auditing. */
state = audit_filter_task(tsk);
if (likely(state == AUDIT_DISABLED))
return 0;
if (!(context = audit_alloc_context(state))) {
audit_log_lost("out of memory in audit_alloc");
return -ENOMEM;
}
/* Preserve login uid */
context->loginuid = -1;
if (current->audit_context)
context->loginuid = current->audit_context->loginuid;
tsk->audit_context = context;
set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
return 0;
}
static inline void audit_free_context(struct audit_context *context)
{
struct audit_context *previous;
int count = 0;
do {
previous = context->previous;
if (previous || (count && count < 10)) {
++count;
printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
" freeing multiple contexts (%d)\n",
context->serial, context->major,
context->name_count, count);
}
audit_free_names(context);
audit_free_aux(context);
kfree(context);
context = previous;
} while (context);
if (count >= 10)
printk(KERN_ERR "audit: freed %d contexts\n", count);
}
static void audit_log_task_info(struct audit_buffer *ab)
{
char name[sizeof(current->comm)];
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
get_task_comm(name, current);
audit_log_format(ab, " comm=");
audit_log_untrustedstring(ab, name);
if (!mm)
return;
down_read(&mm->mmap_sem);
vma = mm->mmap;
while (vma) {
if ((vma->vm_flags & VM_EXECUTABLE) &&
vma->vm_file) {
audit_log_d_path(ab, "exe=",
vma->vm_file->f_dentry,
vma->vm_file->f_vfsmnt);
break;
}
vma = vma->vm_next;
}
up_read(&mm->mmap_sem);
}
static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask)
{
int i;
struct audit_buffer *ab;
struct audit_aux_data *aux;
ab = audit_log_start(context, gfp_mask, AUDIT_SYSCALL);
if (!ab)
return; /* audit_panic has been called */
audit_log_format(ab, "arch=%x syscall=%d",
context->arch, context->major);
if (context->personality != PER_LINUX)
audit_log_format(ab, " per=%lx", context->personality);
if (context->return_valid)
audit_log_format(ab, " success=%s exit=%ld",
(context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
context->return_code);
audit_log_format(ab,
" a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
" pid=%d auid=%u uid=%u gid=%u"
" euid=%u suid=%u fsuid=%u"
" egid=%u sgid=%u fsgid=%u",
context->argv[0],
context->argv[1],
context->argv[2],
context->argv[3],
context->name_count,
context->pid,
context->loginuid,
context->uid,
context->gid,
context->euid, context->suid, context->fsuid,
context->egid, context->sgid, context->fsgid);
audit_log_task_info(ab);
audit_log_end(ab);
for (aux = context->aux; aux; aux = aux->next) {
ab = audit_log_start(context, gfp_mask, aux->type);
if (!ab)
continue; /* audit_panic has been called */
switch (aux->type) {
case AUDIT_IPC: {
struct audit_aux_data_ipcctl *axi = (void *)aux;
audit_log_format(ab,
" qbytes=%lx iuid=%u igid=%u mode=%x",
axi->qbytes, axi->uid, axi->gid, axi->mode);
break; }
case AUDIT_SOCKETCALL: {
int i;
struct audit_aux_data_socketcall *axs = (void *)aux;
audit_log_format(ab, "nargs=%d", axs->nargs);
for (i=0; i<axs->nargs; i++)
audit_log_format(ab, " a%d=%lx", i, axs->args[i]);
break; }
case AUDIT_SOCKADDR: {
struct audit_aux_data_sockaddr *axs = (void *)aux;
audit_log_format(ab, "saddr=");
audit_log_hex(ab, axs->a, axs->len);
break; }
case AUDIT_AVC_PATH: {
struct audit_aux_data_path *axi = (void *)aux;
audit_log_d_path(ab, "path=", axi->dentry, axi->mnt);
break; }
}
audit_log_end(ab);
}
if (context->pwd && context->pwdmnt) {
ab = audit_log_start(context, gfp_mask, AUDIT_CWD);
if (ab) {
audit_log_d_path(ab, "cwd=", context->pwd, context->pwdmnt);
audit_log_end(ab);
}
}
for (i = 0; i < context->name_count; i++) {
ab = audit_log_start(context, gfp_mask, AUDIT_PATH);
if (!ab)
continue; /* audit_panic has been called */
audit_log_format(ab, "item=%d", i);
if (context->names[i].name) {
audit_log_format(ab, " name=");
audit_log_untrustedstring(ab, context->names[i].name);
}
audit_log_format(ab, " flags=%x\n", context->names[i].flags);
if (context->names[i].ino != (unsigned long)-1)
audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#o"
" ouid=%u ogid=%u rdev=%02x:%02x",
context->names[i].ino,
MAJOR(context->names[i].dev),
MINOR(context->names[i].dev),
context->names[i].mode,
context->names[i].uid,
context->names[i].gid,
MAJOR(context->names[i].rdev),
MINOR(context->names[i].rdev));
audit_log_end(ab);
}
}
/**
* audit_free - free a per-task audit context
* @tsk: task whose audit context block to free
*
* Called from copy_process and __put_task_struct.
*/
void audit_free(struct task_struct *tsk)
{
struct audit_context *context;
task_lock(tsk);
context = audit_get_context(tsk, 0, 0);
task_unlock(tsk);
if (likely(!context))
return;
/* Check for system calls that do not go through the exit
* function (e.g., exit_group), then free context block.
* We use GFP_ATOMIC here because we might be doing this
* in the context of the idle thread */
if (context->in_syscall && context->auditable)
audit_log_exit(context, GFP_ATOMIC);
audit_free_context(context);
}
/**
* audit_syscall_entry - fill in an audit record at syscall entry
* @tsk: task being audited
* @arch: architecture type
* @major: major syscall type (function)
* @a1: additional syscall register 1
* @a2: additional syscall register 2
* @a3: additional syscall register 3
* @a4: additional syscall register 4
*
* Fill in audit context at syscall entry. This only happens if the
* audit context was created when the task was created and the state or
* filters demand the audit context be built. If the state from the