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WSL2-Linux-Kernel/kernel/auditsc.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/* auditsc.c -- System-call auditing support
* Handles all system-call specific auditing features.
*
* Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
* Copyright 2005 Hewlett-Packard Development Company, L.P.
* Copyright (C) 2005, 2006 IBM Corporation
* All Rights Reserved.
*
* 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.
*
* POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
* 2006.
*
* The support of additional filter rules compares (>, <, >=, <=) was
* added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
*
* Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
* filesystem information.
*
* Subject and object context labeling support added by <danjones@us.ibm.com>
* and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <asm/types.h>
#include <linux/atomic.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/mm.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/mount.h>
#include <linux/socket.h>
#include <linux/mqueue.h>
#include <linux/audit.h>
#include <linux/personality.h>
#include <linux/time.h>
#include <linux/netlink.h>
#include <linux/compiler.h>
#include <asm/unistd.h>
#include <linux/security.h>
#include <linux/list.h>
#include <linux/binfmts.h>
#include <linux/highmem.h>
#include <linux/syscalls.h>
#include <asm/syscall.h>
#include <linux/capability.h>
#include <linux/fs_struct.h>
#include <linux/compat.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/fsnotify_backend.h>
#include <uapi/linux/limits.h>
#include <uapi/linux/netfilter/nf_tables.h>
#include <uapi/linux/openat2.h> // struct open_how
#include "audit.h"
/* flags stating the success for a syscall */
#define AUDITSC_INVALID 0
#define AUDITSC_SUCCESS 1
#define AUDITSC_FAILURE 2
/* no execve audit message should be longer than this (userspace limits),
* see the note near the top of audit_log_execve_info() about this value */
#define MAX_EXECVE_AUDIT_LEN 7500
/* max length to print of cmdline/proctitle value during audit */
#define MAX_PROCTITLE_AUDIT_LEN 128
/* number of audit rules */
int audit_n_rules;
/* determines whether we collect data for signals sent */
int audit_signals;
struct audit_aux_data {
struct audit_aux_data *next;
int type;
};
/* Number of target pids per aux struct. */
#define AUDIT_AUX_PIDS 16
struct audit_aux_data_pids {
struct audit_aux_data d;
pid_t target_pid[AUDIT_AUX_PIDS];
kuid_t target_auid[AUDIT_AUX_PIDS];
kuid_t target_uid[AUDIT_AUX_PIDS];
unsigned int target_sessionid[AUDIT_AUX_PIDS];
u32 target_sid[AUDIT_AUX_PIDS];
char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
int pid_count;
};
struct audit_aux_data_bprm_fcaps {
struct audit_aux_data d;
struct audit_cap_data fcap;
unsigned int fcap_ver;
struct audit_cap_data old_pcap;
struct audit_cap_data new_pcap;
};
struct audit_tree_refs {
struct audit_tree_refs *next;
struct audit_chunk *c[31];
};
struct audit_nfcfgop_tab {
enum audit_nfcfgop op;
const char *s;
};
static const struct audit_nfcfgop_tab audit_nfcfgs[] = {
{ AUDIT_XT_OP_REGISTER, "xt_register" },
{ AUDIT_XT_OP_REPLACE, "xt_replace" },
{ AUDIT_XT_OP_UNREGISTER, "xt_unregister" },
{ AUDIT_NFT_OP_TABLE_REGISTER, "nft_register_table" },
{ AUDIT_NFT_OP_TABLE_UNREGISTER, "nft_unregister_table" },
{ AUDIT_NFT_OP_CHAIN_REGISTER, "nft_register_chain" },
{ AUDIT_NFT_OP_CHAIN_UNREGISTER, "nft_unregister_chain" },
{ AUDIT_NFT_OP_RULE_REGISTER, "nft_register_rule" },
{ AUDIT_NFT_OP_RULE_UNREGISTER, "nft_unregister_rule" },
{ AUDIT_NFT_OP_SET_REGISTER, "nft_register_set" },
{ AUDIT_NFT_OP_SET_UNREGISTER, "nft_unregister_set" },
{ AUDIT_NFT_OP_SETELEM_REGISTER, "nft_register_setelem" },
{ AUDIT_NFT_OP_SETELEM_UNREGISTER, "nft_unregister_setelem" },
{ AUDIT_NFT_OP_GEN_REGISTER, "nft_register_gen" },
{ AUDIT_NFT_OP_OBJ_REGISTER, "nft_register_obj" },
{ AUDIT_NFT_OP_OBJ_UNREGISTER, "nft_unregister_obj" },
{ AUDIT_NFT_OP_OBJ_RESET, "nft_reset_obj" },
{ AUDIT_NFT_OP_FLOWTABLE_REGISTER, "nft_register_flowtable" },
{ AUDIT_NFT_OP_FLOWTABLE_UNREGISTER, "nft_unregister_flowtable" },
{ AUDIT_NFT_OP_INVALID, "nft_invalid" },
};
static int audit_match_perm(struct audit_context *ctx, int mask)
{
unsigned n;
if (unlikely(!ctx))
return 0;
n = ctx->major;
switch (audit_classify_syscall(ctx->arch, n)) {
case AUDITSC_NATIVE:
if ((mask & AUDIT_PERM_WRITE) &&
audit_match_class(AUDIT_CLASS_WRITE, n))
return 1;
if ((mask & AUDIT_PERM_READ) &&
audit_match_class(AUDIT_CLASS_READ, n))
return 1;
if ((mask & AUDIT_PERM_ATTR) &&
audit_match_class(AUDIT_CLASS_CHATTR, n))
return 1;
return 0;
case AUDITSC_COMPAT: /* 32bit on biarch */
if ((mask & AUDIT_PERM_WRITE) &&
audit_match_class(AUDIT_CLASS_WRITE_32, n))
return 1;
if ((mask & AUDIT_PERM_READ) &&
audit_match_class(AUDIT_CLASS_READ_32, n))
return 1;
if ((mask & AUDIT_PERM_ATTR) &&
audit_match_class(AUDIT_CLASS_CHATTR_32, n))
return 1;
return 0;
case AUDITSC_OPEN:
return mask & ACC_MODE(ctx->argv[1]);
case AUDITSC_OPENAT:
return mask & ACC_MODE(ctx->argv[2]);
case AUDITSC_SOCKETCALL:
return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
case AUDITSC_EXECVE:
return mask & AUDIT_PERM_EXEC;
case AUDITSC_OPENAT2:
return mask & ACC_MODE((u32)ctx->openat2.flags);
default:
return 0;
}
}
static int audit_match_filetype(struct audit_context *ctx, int val)
{
struct audit_names *n;
umode_t mode = (umode_t)val;
if (unlikely(!ctx))
return 0;
list_for_each_entry(n, &ctx->names_list, list) {
if ((n->ino != AUDIT_INO_UNSET) &&
((n->mode & S_IFMT) == mode))
return 1;
}
return 0;
}
/*
* We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
* ->first_trees points to its beginning, ->trees - to the current end of data.
* ->tree_count is the number of free entries in array pointed to by ->trees.
* Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
* "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously,
* it's going to remain 1-element for almost any setup) until we free context itself.
* References in it _are_ dropped - at the same time we free/drop aux stuff.
*/
static void audit_set_auditable(struct audit_context *ctx)
{
if (!ctx->prio) {
ctx->prio = 1;
ctx->current_state = AUDIT_STATE_RECORD;
}
}
static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
{
struct audit_tree_refs *p = ctx->trees;
int left = ctx->tree_count;
if (likely(left)) {
p->c[--left] = chunk;
ctx->tree_count = left;
return 1;
}
if (!p)
return 0;
p = p->next;
if (p) {
p->c[30] = chunk;
ctx->trees = p;
ctx->tree_count = 30;
return 1;
}
return 0;
}
static int grow_tree_refs(struct audit_context *ctx)
{
struct audit_tree_refs *p = ctx->trees;
ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
if (!ctx->trees) {
ctx->trees = p;
return 0;
}
if (p)
p->next = ctx->trees;
else
ctx->first_trees = ctx->trees;
ctx->tree_count = 31;
return 1;
}
static void unroll_tree_refs(struct audit_context *ctx,
struct audit_tree_refs *p, int count)
{
struct audit_tree_refs *q;
int n;
if (!p) {
/* we started with empty chain */
p = ctx->first_trees;
count = 31;
/* if the very first allocation has failed, nothing to do */
if (!p)
return;
}
n = count;
for (q = p; q != ctx->trees; q = q->next, n = 31) {
while (n--) {
audit_put_chunk(q->c[n]);
q->c[n] = NULL;
}
}
while (n-- > ctx->tree_count) {
audit_put_chunk(q->c[n]);
q->c[n] = NULL;
}
ctx->trees = p;
ctx->tree_count = count;
}
static void free_tree_refs(struct audit_context *ctx)
{
struct audit_tree_refs *p, *q;
for (p = ctx->first_trees; p; p = q) {
q = p->next;
kfree(p);
}
}
static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
{
struct audit_tree_refs *p;
int n;
if (!tree)
return 0;
/* full ones */
for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
for (n = 0; n < 31; n++)
if (audit_tree_match(p->c[n], tree))
return 1;
}
/* partial */
if (p) {
for (n = ctx->tree_count; n < 31; n++)
if (audit_tree_match(p->c[n], tree))
return 1;
}
return 0;
}
static int audit_compare_uid(kuid_t uid,
struct audit_names *name,
struct audit_field *f,
struct audit_context *ctx)
{
struct audit_names *n;
int rc;
if (name) {
rc = audit_uid_comparator(uid, f->op, name->uid);
if (rc)
return rc;
}
if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
rc = audit_uid_comparator(uid, f->op, n->uid);
if (rc)
return rc;
}
}
return 0;
}
static int audit_compare_gid(kgid_t gid,
struct audit_names *name,
struct audit_field *f,
struct audit_context *ctx)
{
struct audit_names *n;
int rc;
if (name) {
rc = audit_gid_comparator(gid, f->op, name->gid);
if (rc)
return rc;
}
if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
rc = audit_gid_comparator(gid, f->op, n->gid);
if (rc)
return rc;
}
}
return 0;
}
static int audit_field_compare(struct task_struct *tsk,
const struct cred *cred,
struct audit_field *f,
struct audit_context *ctx,
struct audit_names *name)
{
switch (f->val) {
/* process to file object comparisons */
case AUDIT_COMPARE_UID_TO_OBJ_UID:
return audit_compare_uid(cred->uid, name, f, ctx);
case AUDIT_COMPARE_GID_TO_OBJ_GID:
return audit_compare_gid(cred->gid, name, f, ctx);
case AUDIT_COMPARE_EUID_TO_OBJ_UID:
return audit_compare_uid(cred->euid, name, f, ctx);
case AUDIT_COMPARE_EGID_TO_OBJ_GID:
return audit_compare_gid(cred->egid, name, f, ctx);
case AUDIT_COMPARE_AUID_TO_OBJ_UID:
return audit_compare_uid(audit_get_loginuid(tsk), name, f, ctx);
case AUDIT_COMPARE_SUID_TO_OBJ_UID:
return audit_compare_uid(cred->suid, name, f, ctx);
case AUDIT_COMPARE_SGID_TO_OBJ_GID:
return audit_compare_gid(cred->sgid, name, f, ctx);
case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
return audit_compare_uid(cred->fsuid, name, f, ctx);
case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
return audit_compare_gid(cred->fsgid, name, f, ctx);
/* uid comparisons */
case AUDIT_COMPARE_UID_TO_AUID:
return audit_uid_comparator(cred->uid, f->op,
audit_get_loginuid(tsk));
case AUDIT_COMPARE_UID_TO_EUID:
return audit_uid_comparator(cred->uid, f->op, cred->euid);
case AUDIT_COMPARE_UID_TO_SUID:
return audit_uid_comparator(cred->uid, f->op, cred->suid);
case AUDIT_COMPARE_UID_TO_FSUID:
return audit_uid_comparator(cred->uid, f->op, cred->fsuid);
/* auid comparisons */
case AUDIT_COMPARE_AUID_TO_EUID:
return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
cred->euid);
case AUDIT_COMPARE_AUID_TO_SUID:
return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
cred->suid);
case AUDIT_COMPARE_AUID_TO_FSUID:
return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
cred->fsuid);
/* euid comparisons */
case AUDIT_COMPARE_EUID_TO_SUID:
return audit_uid_comparator(cred->euid, f->op, cred->suid);
case AUDIT_COMPARE_EUID_TO_FSUID:
return audit_uid_comparator(cred->euid, f->op, cred->fsuid);
/* suid comparisons */
case AUDIT_COMPARE_SUID_TO_FSUID:
return audit_uid_comparator(cred->suid, f->op, cred->fsuid);
/* gid comparisons */
case AUDIT_COMPARE_GID_TO_EGID:
return audit_gid_comparator(cred->gid, f->op, cred->egid);
case AUDIT_COMPARE_GID_TO_SGID:
return audit_gid_comparator(cred->gid, f->op, cred->sgid);
case AUDIT_COMPARE_GID_TO_FSGID:
return audit_gid_comparator(cred->gid, f->op, cred->fsgid);
/* egid comparisons */
case AUDIT_COMPARE_EGID_TO_SGID:
return audit_gid_comparator(cred->egid, f->op, cred->sgid);
case AUDIT_COMPARE_EGID_TO_FSGID:
return audit_gid_comparator(cred->egid, f->op, cred->fsgid);
/* sgid comparison */
case AUDIT_COMPARE_SGID_TO_FSGID:
return audit_gid_comparator(cred->sgid, f->op, cred->fsgid);
default:
WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n");
return 0;
}
return 0;
}
/* Determine if any context name data matches a rule's watch data */
/* Compare a task_struct with an audit_rule. Return 1 on match, 0
* otherwise.
*
* If task_creation is true, this is an explicit indication that we are
* filtering a task rule at task creation time. This and tsk == current are
* the only situations where tsk->cred may be accessed without an rcu read lock.
*/
static int audit_filter_rules(struct task_struct *tsk,
struct audit_krule *rule,
struct audit_context *ctx,
struct audit_names *name,
enum audit_state *state,
bool task_creation)
{
const struct cred *cred;
int i, need_sid = 1;
u32 sid;
unsigned int sessionid;
if (ctx && rule->prio <= ctx->prio)
return 0;
cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
for (i = 0; i < rule->field_count; i++) {
struct audit_field *f = &rule->fields[i];
struct audit_names *n;
int result = 0;
pid_t pid;
switch (f->type) {
case AUDIT_PID:
pid = task_tgid_nr(tsk);
result = audit_comparator(pid, f->op, f->val);
break;
case AUDIT_PPID:
if (ctx) {
if (!ctx->ppid)
ctx->ppid = task_ppid_nr(tsk);
result = audit_comparator(ctx->ppid, f->op, f->val);
}
break;
case AUDIT_EXE:
result = audit_exe_compare(tsk, rule->exe);
if (f->op == Audit_not_equal)
result = !result;
break;
case AUDIT_UID:
result = audit_uid_comparator(cred->uid, f->op, f->uid);
break;
case AUDIT_EUID:
result = audit_uid_comparator(cred->euid, f->op, f->uid);
break;
case AUDIT_SUID:
result = audit_uid_comparator(cred->suid, f->op, f->uid);
break;
case AUDIT_FSUID:
result = audit_uid_comparator(cred->fsuid, f->op, f->uid);
break;
case AUDIT_GID:
result = audit_gid_comparator(cred->gid, f->op, f->gid);
if (f->op == Audit_equal) {
if (!result)
result = groups_search(cred->group_info, f->gid);
} else if (f->op == Audit_not_equal) {
if (result)
result = !groups_search(cred->group_info, f->gid);
}
break;
case AUDIT_EGID:
result = audit_gid_comparator(cred->egid, f->op, f->gid);
if (f->op == Audit_equal) {
if (!result)
result = groups_search(cred->group_info, f->gid);
} else if (f->op == Audit_not_equal) {
if (result)
result = !groups_search(cred->group_info, f->gid);
}
break;
case AUDIT_SGID:
result = audit_gid_comparator(cred->sgid, f->op, f->gid);
break;
case AUDIT_FSGID:
result = audit_gid_comparator(cred->fsgid, f->op, f->gid);
break;
case AUDIT_SESSIONID:
sessionid = audit_get_sessionid(tsk);
result = audit_comparator(sessionid, f->op, f->val);
break;
case AUDIT_PERS:
result = audit_comparator(tsk->personality, f->op, f->val);
break;
case AUDIT_ARCH:
if (ctx)
result = audit_comparator(ctx->arch, f->op, f->val);
break;
case AUDIT_EXIT:
if (ctx && ctx->return_valid != AUDITSC_INVALID)
result = audit_comparator(ctx->return_code, f->op, f->val);
break;
case AUDIT_SUCCESS:
if (ctx && ctx->return_valid != AUDITSC_INVALID) {
if (f->val)
result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
else
result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
}
break;
case AUDIT_DEVMAJOR:
if (name) {
if (audit_comparator(MAJOR(name->dev), f->op, f->val) ||
audit_comparator(MAJOR(name->rdev), f->op, f->val))
++result;
} else if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
++result;
break;
}
}
}
break;
case AUDIT_DEVMINOR:
if (name) {
if (audit_comparator(MINOR(name->dev), f->op, f->val) ||
audit_comparator(MINOR(name->rdev), f->op, f->val))
++result;
} else if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
audit_comparator(MINOR(n->rdev), f->op, f->val)) {
++result;
break;
}
}
}
break;
case AUDIT_INODE:
if (name)
result = audit_comparator(name->ino, f->op, f->val);
else if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
if (audit_comparator(n->ino, f->op, f->val)) {
++result;
break;
}
}
}
break;
case AUDIT_OBJ_UID:
if (name) {
result = audit_uid_comparator(name->uid, f->op, f->uid);
} else if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
if (audit_uid_comparator(n->uid, f->op, f->uid)) {
++result;
break;
}
}
}
break;
case AUDIT_OBJ_GID:
if (name) {
result = audit_gid_comparator(name->gid, f->op, f->gid);
} else if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
if (audit_gid_comparator(n->gid, f->op, f->gid)) {
++result;
break;
}
}
}
break;
case AUDIT_WATCH:
if (name) {
result = audit_watch_compare(rule->watch,
name->ino,
name->dev);
if (f->op == Audit_not_equal)
result = !result;
}
break;
case AUDIT_DIR:
if (ctx) {
result = match_tree_refs(ctx, rule->tree);
if (f->op == Audit_not_equal)
result = !result;
}
break;
case AUDIT_LOGINUID:
result = audit_uid_comparator(audit_get_loginuid(tsk),
f->op, f->uid);
break;
case AUDIT_LOGINUID_SET:
result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val);
break;
case AUDIT_SADDR_FAM:
if (ctx && ctx->sockaddr)
result = audit_comparator(ctx->sockaddr->ss_family,
f->op, f->val);
break;
case AUDIT_SUBJ_USER:
case AUDIT_SUBJ_ROLE:
case AUDIT_SUBJ_TYPE:
case AUDIT_SUBJ_SEN:
case AUDIT_SUBJ_CLR:
/* NOTE: this may return negative values indicating
a temporary error. We simply treat this as a
match for now to avoid losing information that
may be wanted. An error message will also be
logged upon error */
if (f->lsm_rule) {
if (need_sid) {
/* @tsk should always be equal to
* @current with the exception of
* fork()/copy_process() in which case
* the new @tsk creds are still a dup
* of @current's creds so we can still
* use security_current_getsecid_subj()
* here even though it always refs
* @current's creds
*/
security_current_getsecid_subj(&sid);
need_sid = 0;
}
result = security_audit_rule_match(sid, f->type,
f->op,
f->lsm_rule);
}
break;
case AUDIT_OBJ_USER:
case AUDIT_OBJ_ROLE:
case AUDIT_OBJ_TYPE:
case AUDIT_OBJ_LEV_LOW:
case AUDIT_OBJ_LEV_HIGH:
/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
also applies here */
if (f->lsm_rule) {
/* Find files that match */
if (name) {
result = security_audit_rule_match(
name->osid,
f->type,
f->op,
f->lsm_rule);
} else if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
if (security_audit_rule_match(
n->osid,
f->type,
f->op,
f->lsm_rule)) {
++result;
break;
}
}
}
/* Find ipc objects that match */
if (!ctx || ctx->type != AUDIT_IPC)
break;
if (security_audit_rule_match(ctx->ipc.osid,
f->type, f->op,
f->lsm_rule))
++result;
}
break;
case AUDIT_ARG0:
case AUDIT_ARG1:
case AUDIT_ARG2:
case AUDIT_ARG3:
if (ctx)
result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
break;
case AUDIT_FILTERKEY:
/* ignore this field for filtering */
result = 1;
break;
case AUDIT_PERM:
result = audit_match_perm(ctx, f->val);
if (f->op == Audit_not_equal)
result = !result;
break;
case AUDIT_FILETYPE:
result = audit_match_filetype(ctx, f->val);
if (f->op == Audit_not_equal)
result = !result;
break;
case AUDIT_FIELD_COMPARE:
result = audit_field_compare(tsk, cred, f, ctx, name);
break;
}
if (!result)
return 0;
}
if (ctx) {
if (rule->filterkey) {
kfree(ctx->filterkey);
ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
}
ctx->prio = rule->prio;
}
switch (rule->action) {
case AUDIT_NEVER:
*state = AUDIT_STATE_DISABLED;
break;
case AUDIT_ALWAYS:
*state = AUDIT_STATE_RECORD;
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, char **key)
{
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, NULL,
&state, true)) {
if (state == AUDIT_STATE_RECORD)
*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
rcu_read_unlock();
return state;
}
}
rcu_read_unlock();
return AUDIT_STATE_BUILD;
}
static int audit_in_mask(const struct audit_krule *rule, unsigned long val)
{
int word, bit;
if (val > 0xffffffff)
return false;
word = AUDIT_WORD(val);
if (word >= AUDIT_BITMASK_SIZE)
return false;
bit = AUDIT_BIT(val);
return rule->mask[word] & bit;
}
/**
* audit_filter_uring - apply filters to an io_uring operation
* @tsk: associated task
* @ctx: audit context
*/
static void audit_filter_uring(struct task_struct *tsk,
struct audit_context *ctx)
{
struct audit_entry *e;
enum audit_state state;
if (auditd_test_task(tsk))
return;
rcu_read_lock();
list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_URING_EXIT],
list) {
if (audit_in_mask(&e->rule, ctx->uring_op) &&
audit_filter_rules(tsk, &e->rule, ctx, NULL, &state,
false)) {
rcu_read_unlock();
ctx->current_state = state;
return;
}
}
rcu_read_unlock();
}
/* At syscall 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_STATE_BUILD).
*/
static void audit_filter_syscall(struct task_struct *tsk,
struct audit_context *ctx)
{
struct audit_entry *e;
enum audit_state state;
if (auditd_test_task(tsk))
return;
rcu_read_lock();
list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_EXIT], list) {
if (audit_in_mask(&e->rule, ctx->major) &&
audit_filter_rules(tsk, &e->rule, ctx, NULL,
&state, false)) {
rcu_read_unlock();
ctx->current_state = state;
return;
}
}
rcu_read_unlock();
return;
}
/*
* Given an audit_name check the inode hash table to see if they match.
* Called holding the rcu read lock to protect the use of audit_inode_hash
*/
static int audit_filter_inode_name(struct task_struct *tsk,
struct audit_names *n,
struct audit_context *ctx) {
int h = audit_hash_ino((u32)n->ino);
struct list_head *list = &audit_inode_hash[h];
struct audit_entry *e;
enum audit_state state;
list_for_each_entry_rcu(e, list, list) {
if (audit_in_mask(&e->rule, ctx->major) &&
audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
ctx->current_state = state;
return 1;
}
}
return 0;
}
/* At syscall exit time, this filter is called if any audit_names have been
* collected during syscall processing. We only check rules in sublists at hash
* buckets applicable to the inode numbers in audit_names.
* Regarding audit_state, same rules apply as for audit_filter_syscall().
*/
void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
{
struct audit_names *n;
if (auditd_test_task(tsk))
return;
rcu_read_lock();
list_for_each_entry(n, &ctx->names_list, list) {
if (audit_filter_inode_name(tsk, n, ctx))
break;
}
rcu_read_unlock();
}
static inline void audit_proctitle_free(struct audit_context *context)
{
kfree(context->proctitle.value);
context->proctitle.value = NULL;
context->proctitle.len = 0;
}
static inline void audit_free_module(struct audit_context *context)
{
if (context->type == AUDIT_KERN_MODULE) {
kfree(context->module.name);
context->module.name = NULL;
}
}
static inline void audit_free_names(struct audit_context *context)
{
struct audit_names *n, *next;
list_for_each_entry_safe(n, next, &context->names_list, list) {
list_del(&n->list);
if (n->name)
putname(n->name);
if (n->should_free)
kfree(n);
}
context->name_count = 0;
path_put(&context->pwd);
context->pwd.dentry = NULL;
context->pwd.mnt = NULL;
}
static inline void audit_free_aux(struct audit_context *context)
{
struct audit_aux_data *aux;
while ((aux = context->aux)) {
context->aux = aux->next;
kfree(aux);
}
context->aux = NULL;
while ((aux = context->aux_pids)) {
context->aux_pids = aux->next;
kfree(aux);
}
context->aux_pids = NULL;
}
/**
* audit_reset_context - reset a audit_context structure
* @ctx: the audit_context to reset
*
* All fields in the audit_context will be reset to an initial state, all
* references held by fields will be dropped, and private memory will be
* released. When this function returns the audit_context will be suitable
* for reuse, so long as the passed context is not NULL or a dummy context.
*/
static void audit_reset_context(struct audit_context *ctx)
{
if (!ctx)
return;
/* if ctx is non-null, reset the "ctx->context" regardless */
ctx->context = AUDIT_CTX_UNUSED;
if (ctx->dummy)
return;
/*
* NOTE: It shouldn't matter in what order we release the fields, so
* release them in the order in which they appear in the struct;
* this gives us some hope of quickly making sure we are
* resetting the audit_context properly.
*
* Other things worth mentioning:
* - we don't reset "dummy"
* - we don't reset "state", we do reset "current_state"
* - we preserve "filterkey" if "state" is AUDIT_STATE_RECORD
* - much of this is likely overkill, but play it safe for now
* - we really need to work on improving the audit_context struct
*/
ctx->current_state = ctx->state;
ctx->serial = 0;
ctx->major = 0;
ctx->uring_op = 0;
ctx->ctime = (struct timespec64){ .tv_sec = 0, .tv_nsec = 0 };
memset(ctx->argv, 0, sizeof(ctx->argv));
ctx->return_code = 0;
ctx->prio = (ctx->state == AUDIT_STATE_RECORD ? ~0ULL : 0);
ctx->return_valid = AUDITSC_INVALID;
audit_free_names(ctx);
if (ctx->state != AUDIT_STATE_RECORD) {
kfree(ctx->filterkey);
ctx->filterkey = NULL;
}
audit_free_aux(ctx);
kfree(ctx->sockaddr);
ctx->sockaddr = NULL;
ctx->sockaddr_len = 0;
ctx->ppid = 0;
ctx->uid = ctx->euid = ctx->suid = ctx->fsuid = KUIDT_INIT(0);
ctx->gid = ctx->egid = ctx->sgid = ctx->fsgid = KGIDT_INIT(0);
ctx->personality = 0;
ctx->arch = 0;
ctx->target_pid = 0;
ctx->target_auid = ctx->target_uid = KUIDT_INIT(0);
ctx->target_sessionid = 0;
ctx->target_sid = 0;
ctx->target_comm[0] = '\0';
unroll_tree_refs(ctx, NULL, 0);
WARN_ON(!list_empty(&ctx->killed_trees));
audit_free_module(ctx);
ctx->fds[0] = -1;
ctx->type = 0; /* reset last for audit_free_*() */
}
static inline struct audit_context *audit_alloc_context(enum audit_state state)
{
struct audit_context *context;
context = kzalloc(sizeof(*context), GFP_KERNEL);
if (!context)
return NULL;
context->context = AUDIT_CTX_UNUSED;
context->state = state;
context->prio = state == AUDIT_STATE_RECORD ? ~0ULL : 0;
INIT_LIST_HEAD(&context->killed_trees);
INIT_LIST_HEAD(&context->names_list);
context->fds[0] = -1;
context->return_valid = AUDITSC_INVALID;
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;
char *key = NULL;
if (likely(!audit_ever_enabled))
return 0;
state = audit_filter_task(tsk, &key);
if (state == AUDIT_STATE_DISABLED) {
clear_task_syscall_work(tsk, SYSCALL_AUDIT);
return 0;
}
if (!(context = audit_alloc_context(state))) {
kfree(key);
audit_log_lost("out of memory in audit_alloc");
return -ENOMEM;
}
context->filterkey = key;
audit_set_context(tsk, context);
set_task_syscall_work(tsk, SYSCALL_AUDIT);
return 0;
}
static inline void audit_free_context(struct audit_context *context)
{
/* resetting is extra work, but it is likely just noise */
audit_reset_context(context);
audit_proctitle_free(context);
free_tree_refs(context);
kfree(context->filterkey);
kfree(context);
}
static int audit_log_pid_context(struct audit_context *context, pid_t pid,
kuid_t auid, kuid_t uid, unsigned int sessionid,
u32 sid, char *comm)
{
struct audit_buffer *ab;
char *ctx = NULL;
u32 len;
int rc = 0;
ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
if (!ab)
return rc;
audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
from_kuid(&init_user_ns, auid),
from_kuid(&init_user_ns, uid), sessionid);
if (sid) {
if (security_secid_to_secctx(sid, &ctx, &len)) {
audit_log_format(ab, " obj=(none)");
rc = 1;
} else {
audit_log_format(ab, " obj=%s", ctx);
security_release_secctx(ctx, len);
}
}
audit_log_format(ab, " ocomm=");
audit_log_untrustedstring(ab, comm);
audit_log_end(ab);
return rc;
}
static void audit_log_execve_info(struct audit_context *context,
struct audit_buffer **ab)
{
long len_max;
long len_rem;
long len_full;
long len_buf;
long len_abuf = 0;
long len_tmp;
bool require_data;
bool encode;
unsigned int iter;
unsigned int arg;
char *buf_head;
char *buf;
const char __user *p = (const char __user *)current->mm->arg_start;
/* NOTE: this buffer needs to be large enough to hold all the non-arg
* data we put in the audit record for this argument (see the
* code below) ... at this point in time 96 is plenty */
char abuf[96];
/* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the
* current value of 7500 is not as important as the fact that it
* is less than 8k, a setting of 7500 gives us plenty of wiggle
* room if we go over a little bit in the logging below */
WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500);
len_max = MAX_EXECVE_AUDIT_LEN;
/* scratch buffer to hold the userspace args */
buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
if (!buf_head) {
audit_panic("out of memory for argv string");
return;
}
buf = buf_head;
audit_log_format(*ab, "argc=%d", context->execve.argc);
len_rem = len_max;
len_buf = 0;
len_full = 0;
require_data = true;
encode = false;
iter = 0;
arg = 0;
do {
/* NOTE: we don't ever want to trust this value for anything
* serious, but the audit record format insists we
* provide an argument length for really long arguments,
* e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but
* to use strncpy_from_user() to obtain this value for
* recording in the log, although we don't use it
* anywhere here to avoid a double-fetch problem */
if (len_full == 0)
len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1;
/* read more data from userspace */
if (require_data) {
/* can we make more room in the buffer? */
if (buf != buf_head) {
memmove(buf_head, buf, len_buf);
buf = buf_head;
}
/* fetch as much as we can of the argument */
len_tmp = strncpy_from_user(&buf_head[len_buf], p,
len_max - len_buf);
if (len_tmp == -EFAULT) {
/* unable to copy from userspace */
send_sig(SIGKILL, current, 0);
goto out;
} else if (len_tmp == (len_max - len_buf)) {
/* buffer is not large enough */
require_data = true;
/* NOTE: if we are going to span multiple
* buffers force the encoding so we stand
* a chance at a sane len_full value and
* consistent record encoding */
encode = true;
len_full = len_full * 2;
p += len_tmp;
} else {
require_data = false;
if (!encode)
encode = audit_string_contains_control(
buf, len_tmp);
/* try to use a trusted value for len_full */
if (len_full < len_max)
len_full = (encode ?
len_tmp * 2 : len_tmp);
p += len_tmp + 1;
}
len_buf += len_tmp;
buf_head[len_buf] = '\0';
/* length of the buffer in the audit record? */
len_abuf = (encode ? len_buf * 2 : len_buf + 2);
}
/* write as much as we can to the audit log */
if (len_buf >= 0) {
/* NOTE: some magic numbers here - basically if we
* can't fit a reasonable amount of data into the
* existing audit buffer, flush it and start with
* a new buffer */
if ((sizeof(abuf) + 8) > len_rem) {
len_rem = len_max;
audit_log_end(*ab);
*ab = audit_log_start(context,
GFP_KERNEL, AUDIT_EXECVE);
if (!*ab)
goto out;
}
/* create the non-arg portion of the arg record */
len_tmp = 0;
if (require_data || (iter > 0) ||
((len_abuf + sizeof(abuf)) > len_rem)) {
if (iter == 0) {
len_tmp += snprintf(&abuf[len_tmp],
sizeof(abuf) - len_tmp,
" a%d_len=%lu",
arg, len_full);
}
len_tmp += snprintf(&abuf[len_tmp],
sizeof(abuf) - len_tmp,
" a%d[%d]=", arg, iter++);
} else
len_tmp += snprintf(&abuf[len_tmp],
sizeof(abuf) - len_tmp,
" a%d=", arg);
WARN_ON(len_tmp >= sizeof(abuf));
abuf[sizeof(abuf) - 1] = '\0';
/* log the arg in the audit record */
audit_log_format(*ab, "%s", abuf);
len_rem -= len_tmp;
len_tmp = len_buf;
if (encode) {
if (len_abuf > len_rem)
len_tmp = len_rem / 2; /* encoding */
audit_log_n_hex(*ab, buf, len_tmp);
len_rem -= len_tmp * 2;
len_abuf -= len_tmp * 2;
} else {
if (len_abuf > len_rem)
len_tmp = len_rem - 2; /* quotes */
audit_log_n_string(*ab, buf, len_tmp);
len_rem -= len_tmp + 2;
/* don't subtract the "2" because we still need
* to add quotes to the remaining string */
len_abuf -= len_tmp;
}
len_buf -= len_tmp;
buf += len_tmp;
}
/* ready to move to the next argument? */
if ((len_buf == 0) && !require_data) {
arg++;
iter = 0;
len_full = 0;
require_data = true;
encode = false;
}
} while (arg < context->execve.argc);
/* NOTE: the caller handles the final audit_log_end() call */
out:
kfree(buf_head);
}
static void audit_log_cap(struct audit_buffer *ab, char *prefix,
kernel_cap_t *cap)
{
int i;
if (cap_isclear(*cap)) {
audit_log_format(ab, " %s=0", prefix);
return;
}
audit_log_format(ab, " %s=", prefix);
CAP_FOR_EACH_U32(i)
audit_log_format(ab, "%08x", cap->cap[CAP_LAST_U32 - i]);
}
static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
{
if (name->fcap_ver == -1) {
audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?");
return;
}
audit_log_cap(ab, "cap_fp", &name->fcap.permitted);
audit_log_cap(ab, "cap_fi", &name->fcap.inheritable);
audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d",
name->fcap.fE, name->fcap_ver,
from_kuid(&init_user_ns, name->fcap.rootid));
}
static void audit_log_time(struct audit_context *context, struct audit_buffer **ab)
{
const struct audit_ntp_data *ntp = &context->time.ntp_data;
const struct timespec64 *tk = &context->time.tk_injoffset;
static const char * const ntp_name[] = {
"offset",
"freq",
"status",
"tai",
"tick",
"adjust",
};
int type;
if (context->type == AUDIT_TIME_ADJNTPVAL) {
for (type = 0; type < AUDIT_NTP_NVALS; type++) {
if (ntp->vals[type].newval != ntp->vals[type].oldval) {
if (!*ab) {
*ab = audit_log_start(context,
GFP_KERNEL,
AUDIT_TIME_ADJNTPVAL);
if (!*ab)
return;
}
audit_log_format(*ab, "op=%s old=%lli new=%lli",
ntp_name[type],
ntp->vals[type].oldval,
ntp->vals[type].newval);
audit_log_end(*ab);
*ab = NULL;
}
}
}
if (tk->tv_sec != 0 || tk->tv_nsec != 0) {
if (!*ab) {
*ab = audit_log_start(context, GFP_KERNEL,
AUDIT_TIME_INJOFFSET);
if (!*ab)
return;
}
audit_log_format(*ab, "sec=%lli nsec=%li",
(long long)tk->tv_sec, tk->tv_nsec);
audit_log_end(*ab);
*ab = NULL;
}
}
static void show_special(struct audit_context *context, int *call_panic)
{
struct audit_buffer *ab;
int i;
ab = audit_log_start(context, GFP_KERNEL, context->type);
if (!ab)
return;
switch (context->type) {
case AUDIT_SOCKETCALL: {
int nargs = context->socketcall.nargs;
audit_log_format(ab, "nargs=%d", nargs);
for (i = 0; i < nargs; i++)
audit_log_format(ab, " a%d=%lx", i,
context->socketcall.args[i]);
break; }
case AUDIT_IPC: {
u32 osid = context->ipc.osid;
audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
from_kuid(&init_user_ns, context->ipc.uid),
from_kgid(&init_user_ns, context->ipc.gid),
context->ipc.mode);
if (osid) {
char *ctx = NULL;
u32 len;
if (security_secid_to_secctx(osid, &ctx, &len)) {
audit_log_format(ab, " osid=%u", osid);
*call_panic = 1;
} else {
audit_log_format(ab, " obj=%s", ctx);
security_release_secctx(ctx, len);
}
}
if (context->ipc.has_perm) {
audit_log_end(ab);
ab = audit_log_start(context, GFP_KERNEL,
AUDIT_IPC_SET_PERM);
if (unlikely(!ab))
return;
audit_log_format(ab,
"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
context->ipc.qbytes,
context->ipc.perm_uid,
context->ipc.perm_gid,
context->ipc.perm_mode);
}
break; }
case AUDIT_MQ_OPEN:
audit_log_format(ab,
"oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
"mq_msgsize=%ld mq_curmsgs=%ld",
context->mq_open.oflag, context->mq_open.mode,
context->mq_open.attr.mq_flags,
context->mq_open.attr.mq_maxmsg,
context->mq_open.attr.mq_msgsize,
context->mq_open.attr.mq_curmsgs);
break;
case AUDIT_MQ_SENDRECV:
audit_log_format(ab,
"mqdes=%d msg_len=%zd msg_prio=%u "
"abs_timeout_sec=%lld abs_timeout_nsec=%ld",
context->mq_sendrecv.mqdes,
context->mq_sendrecv.msg_len,
context->mq_sendrecv.msg_prio,
(long long) context->mq_sendrecv.abs_timeout.tv_sec,
context->mq_sendrecv.abs_timeout.tv_nsec);
break;
case AUDIT_MQ_NOTIFY:
audit_log_format(ab, "mqdes=%d sigev_signo=%d",
context->mq_notify.mqdes,
context->mq_notify.sigev_signo);
break;
case AUDIT_MQ_GETSETATTR: {
struct mq_attr *attr = &context->mq_getsetattr.mqstat;
audit_log_format(ab,
"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
"mq_curmsgs=%ld ",
context->mq_getsetattr.mqdes,
attr->mq_flags, attr->mq_maxmsg,
attr->mq_msgsize, attr->mq_curmsgs);
break; }
case AUDIT_CAPSET:
audit_log_format(ab, "pid=%d", context->capset.pid);
audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient);
break;
case AUDIT_MMAP:
audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
context->mmap.flags);
break;
case AUDIT_OPENAT2:
audit_log_format(ab, "oflag=0%llo mode=0%llo resolve=0x%llx",
context->openat2.flags,
context->openat2.mode,
context->openat2.resolve);
break;
case AUDIT_EXECVE:
audit_log_execve_info(context, &ab);
break;
case AUDIT_KERN_MODULE:
audit_log_format(ab, "name=");
if (context->module.name) {
audit_log_untrustedstring(ab, context->module.name);
} else
audit_log_format(ab, "(null)");
break;
case AUDIT_TIME_ADJNTPVAL:
case AUDIT_TIME_INJOFFSET:
/* this call deviates from the rest, eating the buffer */
audit_log_time(context, &ab);
break;
}
audit_log_end(ab);
}
static inline int audit_proctitle_rtrim(char *proctitle, int len)
{
char *end = proctitle + len - 1;
while (end > proctitle && !isprint(*end))
end--;
/* catch the case where proctitle is only 1 non-print character */
len = end - proctitle + 1;
len -= isprint(proctitle[len-1]) == 0;
return len;
}
/*
* audit_log_name - produce AUDIT_PATH record from struct audit_names
* @context: audit_context for the task
* @n: audit_names structure with reportable details
* @path: optional path to report instead of audit_names->name
* @record_num: record number to report when handling a list of names
* @call_panic: optional pointer to int that will be updated if secid fails
*/
static void audit_log_name(struct audit_context *context, struct audit_names *n,
const struct path *path, int record_num, int *call_panic)
{
struct audit_buffer *ab;
ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
if (!ab)
return;
audit_log_format(ab, "item=%d", record_num);
if (path)
audit_log_d_path(ab, " name=", path);
else if (n->name) {
switch (n->name_len) {
case AUDIT_NAME_FULL:
/* log the full path */
audit_log_format(ab, " name=");
audit_log_untrustedstring(ab, n->name->name);
break;
case 0:
/* name was specified as a relative path and the
* directory component is the cwd
*/
if (context->pwd.dentry && context->pwd.mnt)
audit_log_d_path(ab, " name=", &context->pwd);
else
audit_log_format(ab, " name=(null)");
break;
default:
/* log the name's directory component */
audit_log_format(ab, " name=");
audit_log_n_untrustedstring(ab, n->name->name,
n->name_len);
}
} else
audit_log_format(ab, " name=(null)");
if (n->ino != AUDIT_INO_UNSET)
audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#ho ouid=%u ogid=%u rdev=%02x:%02x",
n->ino,
MAJOR(n->dev),
MINOR(n->dev),
n->mode,
from_kuid(&init_user_ns, n->uid),
from_kgid(&init_user_ns, n->gid),
MAJOR(n->rdev),
MINOR(n->rdev));
if (n->osid != 0) {
char *ctx = NULL;
u32 len;
if (security_secid_to_secctx(
n->osid, &ctx, &len)) {
audit_log_format(ab, " osid=%u", n->osid);
if (call_panic)
*call_panic = 2;
} else {
audit_log_format(ab, " obj=%s", ctx);
security_release_secctx(ctx, len);
}
}
/* log the audit_names record type */
switch (n->type) {
case AUDIT_TYPE_NORMAL:
audit_log_format(ab, " nametype=NORMAL");
break;
case AUDIT_TYPE_PARENT:
audit_log_format(ab, " nametype=PARENT");
break;
case AUDIT_TYPE_CHILD_DELETE:
audit_log_format(ab, " nametype=DELETE");
break;
case AUDIT_TYPE_CHILD_CREATE:
audit_log_format(ab, " nametype=CREATE");
break;
default:
audit_log_format(ab, " nametype=UNKNOWN");
break;
}
audit_log_fcaps(ab, n);
audit_log_end(ab);
}
static void audit_log_proctitle(void)
{
int res;
char *buf;
char *msg = "(null)";
int len = strlen(msg);
struct audit_context *context = audit_context();
struct audit_buffer *ab;
ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE);
if (!ab)
return; /* audit_panic or being filtered */
audit_log_format(ab, "proctitle=");
/* Not cached */
if (!context->proctitle.value) {
buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL);
if (!buf)
goto out;
/* Historically called this from procfs naming */
res = get_cmdline(current, buf, MAX_PROCTITLE_AUDIT_LEN);
if (res == 0) {
kfree(buf);
goto out;
}
res = audit_proctitle_rtrim(buf, res);
if (res == 0) {
kfree(buf);
goto out;
}
context->proctitle.value = buf;
context->proctitle.len = res;
}
msg = context->proctitle.value;
len = context->proctitle.len;
out:
audit_log_n_untrustedstring(ab, msg, len);
audit_log_end(ab);
}
/**
* audit_log_uring - generate a AUDIT_URINGOP record
* @ctx: the audit context
*/
static void audit_log_uring(struct audit_context *ctx)
{
struct audit_buffer *ab;
const struct cred *cred;
ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_URINGOP);
if (!ab)
return;
cred = current_cred();
audit_log_format(ab, "uring_op=%d", ctx->uring_op);
if (ctx->return_valid != AUDITSC_INVALID)
audit_log_format(ab, " success=%s exit=%ld",
(ctx->return_valid == AUDITSC_SUCCESS ?
"yes" : "no"),
ctx->return_code);
audit_log_format(ab,
" items=%d"
" ppid=%d pid=%d uid=%u gid=%u euid=%u suid=%u"
" fsuid=%u egid=%u sgid=%u fsgid=%u",
ctx->name_count,
task_ppid_nr(current), task_tgid_nr(current),
from_kuid(&init_user_ns, cred->uid),
from_kgid(&init_user_ns, cred->gid),
from_kuid(&init_user_ns, cred->euid),
from_kuid(&init_user_ns, cred->suid),
from_kuid(&init_user_ns, cred->fsuid),
from_kgid(&init_user_ns, cred->egid),
from_kgid(&init_user_ns, cred->sgid),
from_kgid(&init_user_ns, cred->fsgid));
audit_log_task_context(ab);
audit_log_key(ab, ctx->filterkey);
audit_log_end(ab);
}
static void audit_log_exit(void)
{
int i, call_panic = 0;
struct audit_context *context = audit_context();
struct audit_buffer *ab;
struct audit_aux_data *aux;
struct audit_names *n;
context->personality = current->personality;
switch (context->context) {
case AUDIT_CTX_SYSCALL:
ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
if (!ab)
return;
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 != AUDITSC_INVALID)
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",
context->argv[0],
context->argv[1],
context->argv[2],
context->argv[3],
context->name_count);
audit_log_task_info(ab);
audit_log_key(ab, context->filterkey);
audit_log_end(ab);
break;
case AUDIT_CTX_URING:
audit_log_uring(context);
break;
default:
BUG();
break;
}
for (aux = context->aux; aux; aux = aux->next) {
ab = audit_log_start(context, GFP_KERNEL, aux->type);
if (!ab)
continue; /* audit_panic has been called */
switch (aux->type) {
case AUDIT_BPRM_FCAPS: {
struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
audit_log_format(ab, "fver=%x", axs->fcap_ver);
audit_log_cap(ab, "fp", &axs->fcap.permitted);
audit_log_cap(ab, "fi", &axs->fcap.inheritable);
audit_log_format(ab, " fe=%d", axs->fcap.fE);
audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient);
audit_log_cap(ab, "pp", &axs->new_pcap.permitted);
audit_log_cap(ab, "pi", &axs->new_pcap.inheritable);
audit_log_cap(ab, "pe", &axs->new_pcap.effective);
audit_log_cap(ab, "pa", &axs->new_pcap.ambient);
audit_log_format(ab, " frootid=%d",
from_kuid(&init_user_ns,
axs->fcap.rootid));
break; }
}
audit_log_end(ab);
}
if (context->type)
show_special(context, &call_panic);
if (context->fds[0] >= 0) {
ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
if (ab) {
audit_log_format(ab, "fd0=%d fd1=%d",
context->fds[0], context->fds[1]);
audit_log_end(ab);
}
}
if (context->sockaddr_len) {
ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
if (ab) {
audit_log_format(ab, "saddr=");
audit_log_n_hex(ab, (void *)context->sockaddr,
context->sockaddr_len);
audit_log_end(ab);
}
}
for (aux = context->aux_pids; aux; aux = aux->next) {
struct audit_aux_data_pids *axs = (void *)aux;
for (i = 0; i < axs->pid_count; i++)
if (audit_log_pid_context(context, axs->target_pid[i],
axs->target_auid[i],
axs->target_uid[i],
axs->target_sessionid[i],
axs->target_sid[i],
axs->target_comm[i]))
call_panic = 1;
}
if (context->target_pid &&
audit_log_pid_context(context, context->target_pid,
context->target_auid, context->target_uid,
context->target_sessionid,
context->target_sid, context->target_comm))
call_panic = 1;
if (context->pwd.dentry && context->pwd.mnt) {
ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
if (ab) {
audit_log_d_path(ab, "cwd=", &context->pwd);
audit_log_end(ab);
}
}
i = 0;
list_for_each_entry(n, &context->names_list, list) {
if (n->hidden)
continue;
audit_log_name(context, n, NULL, i++, &call_panic);
}
if (context->context == AUDIT_CTX_SYSCALL)
audit_log_proctitle();
/* Send end of event record to help user space know we are finished */
ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
if (ab)
audit_log_end(ab);
if (call_panic)
audit_panic("error in audit_log_exit()");
}
/**
* __audit_free - free a per-task audit context
* @tsk: task whose audit context block to free
*
* Called from copy_process, do_exit, and the io_uring code
*/
void __audit_free(struct task_struct *tsk)
{
struct audit_context *context = tsk->audit_context;
if (!context)
return;
/* this may generate CONFIG_CHANGE records */
if (!list_empty(&context->killed_trees))
audit_kill_trees(context);
/* We are called either by do_exit() or the fork() error handling code;
* in the former case tsk == current and in the latter tsk is a
* random task_struct that doesn't have any meaningful data we
* need to log via audit_log_exit().
*/
if (tsk == current && !context->dummy) {
context->return_valid = AUDITSC_INVALID;
context->return_code = 0;
if (context->context == AUDIT_CTX_SYSCALL) {
audit_filter_syscall(tsk, context);
audit_filter_inodes(tsk, context);
if (context->current_state == AUDIT_STATE_RECORD)
audit_log_exit();
} else if (context->context == AUDIT_CTX_URING) {
/* TODO: verify this case is real and valid */
audit_filter_uring(tsk, context);
audit_filter_inodes(tsk, context);
if (context->current_state == AUDIT_STATE_RECORD)
audit_log_uring(context);
}
}
audit_set_context(tsk, NULL);
audit_free_context(context);
}
/**
* audit_return_fixup - fixup the return codes in the audit_context
* @ctx: the audit_context
* @success: true/false value to indicate if the operation succeeded or not
* @code: operation return code
*
* We need to fixup the return code in the audit logs if the actual return
* codes are later going to be fixed by the arch specific signal handlers.
*/
static void audit_return_fixup(struct audit_context *ctx,
int success, long code)
{
/*
* This is actually a test for:
* (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
* (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
*
* but is faster than a bunch of ||
*/
if (unlikely(code <= -ERESTARTSYS) &&
(code >= -ERESTART_RESTARTBLOCK) &&
(code != -ENOIOCTLCMD))
ctx->return_code = -EINTR;
else
ctx->return_code = code;
ctx->return_valid = (success ? AUDITSC_SUCCESS : AUDITSC_FAILURE);
}
/**
* __audit_uring_entry - prepare the kernel task's audit context for io_uring
* @op: the io_uring opcode
*
* This is similar to audit_syscall_entry() but is intended for use by io_uring
* operations. This function should only ever be called from
* audit_uring_entry() as we rely on the audit context checking present in that
* function.
*/
void __audit_uring_entry(u8 op)
{
struct audit_context *ctx = audit_context();
if (ctx->state == AUDIT_STATE_DISABLED)
return;
/*
* NOTE: It's possible that we can be called from the process' context
* before it returns to userspace, and before audit_syscall_exit()
* is called. In this case there is not much to do, just record
* the io_uring details and return.
*/
ctx->uring_op = op;
if (ctx->context == AUDIT_CTX_SYSCALL)
return;
ctx->dummy = !audit_n_rules;
if (!ctx->dummy && ctx->state == AUDIT_STATE_BUILD)
ctx->prio = 0;
ctx->context = AUDIT_CTX_URING;
ctx->current_state = ctx->state;
ktime_get_coarse_real_ts64(&ctx->ctime);
}
/**
* __audit_uring_exit - wrap up the kernel task's audit context after io_uring
* @success: true/false value to indicate if the operation succeeded or not
* @code: operation return code
*
* This is similar to audit_syscall_exit() but is intended for use by io_uring
* operations. This function should only ever be called from
* audit_uring_exit() as we rely on the audit context checking present in that
* function.
*/
void __audit_uring_exit(int success, long code)
{
struct audit_context *ctx = audit_context();
if (ctx->dummy) {
if (ctx->context != AUDIT_CTX_URING)
return;
goto out;
}
audit_return_fixup(ctx, success, code);
if (ctx->context == AUDIT_CTX_SYSCALL) {
/*
* NOTE: See the note in __audit_uring_entry() about the case
* where we may be called from process context before we
* return to userspace via audit_syscall_exit(). In this
* case we simply emit a URINGOP record and bail, the
* normal syscall exit handling will take care of
* everything else.
* It is also worth mentioning that when we are called,
* the current process creds may differ from the creds
* used during the normal syscall processing; keep that
* in mind if/when we move the record generation code.
*/
/*
* We need to filter on the syscall info here to decide if we
* should emit a URINGOP record. I know it seems odd but this
* solves the problem where users have a filter to block *all*
* syscall records in the "exit" filter; we want to preserve
* the behavior here.
*/
audit_filter_syscall(current, ctx);
if (ctx->current_state != AUDIT_STATE_RECORD)
audit_filter_uring(current, ctx);
audit_filter_inodes(current, ctx);
if (ctx->current_state != AUDIT_STATE_RECORD)
return;
audit_log_uring(ctx);
return;
}
/* this may generate CONFIG_CHANGE records */
if (!list_empty(&ctx->killed_trees))
audit_kill_trees(ctx);
/* run through both filters to ensure we set the filterkey properly */
audit_filter_uring(current, ctx);
audit_filter_inodes(current, ctx);
if (ctx->current_state != AUDIT_STATE_RECORD)
goto out;
audit_log_exit();
out:
audit_reset_context(ctx);
}
/**
* __audit_syscall_entry - fill in an audit record at syscall entry
* @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
* per-task filter or from the per-syscall filter is AUDIT_STATE_RECORD,
* then the record will be written at syscall exit time (otherwise, it
* will only be written if another part of the kernel requests that it
* be written).
*/
void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
unsigned long a3, unsigned long a4)
{
struct audit_context *context = audit_context();
enum audit_state state;
if (!audit_enabled || !context)
return;
WARN_ON(context->context != AUDIT_CTX_UNUSED);
WARN_ON(context->name_count);
if (context->context != AUDIT_CTX_UNUSED || context->name_count) {
audit_panic("unrecoverable error in audit_syscall_entry()");
return;
}
state = context->state;
if (state == AUDIT_STATE_DISABLED)
return;
context->dummy = !audit_n_rules;
if (!context->dummy && state == AUDIT_STATE_BUILD) {
context->prio = 0;
if (auditd_test_task(current))
return;
}
context->arch = syscall_get_arch(current);
context->major = major;
context->argv[0] = a1;
context->argv[1] = a2;
context->argv[2] = a3;
context->argv[3] = a4;
context->context = AUDIT_CTX_SYSCALL;
context->current_state = state;
ktime_get_coarse_real_ts64(&context->ctime);
}
/**
* __audit_syscall_exit - deallocate audit context after a system call
* @success: success value of the syscall
* @return_code: return value of the syscall
*
* Tear down after system call. If the audit context has been marked as
* auditable (either because of the AUDIT_STATE_RECORD state from
* filtering, or because some other part of the kernel wrote an audit
* message), then write out the syscall information. In call cases,
* free the names stored from getname().
*/
void __audit_syscall_exit(int success, long return_code)
{
struct audit_context *context = audit_context();
if (!context || context->dummy ||
context->context != AUDIT_CTX_SYSCALL)
goto out;
/* this may generate CONFIG_CHANGE records */
if (!list_empty(&context->killed_trees))
audit_kill_trees(context);
audit_return_fixup(context, success, return_code);
/* run through both filters to ensure we set the filterkey properly */
audit_filter_syscall(current, context);
audit_filter_inodes(current, context);
if (context->current_state != AUDIT_STATE_RECORD)
goto out;
audit_log_exit();
out:
audit_reset_context(context);
}
static inline void handle_one(const struct inode *inode)
{
struct audit_context *context;
struct audit_tree_refs *p;
struct audit_chunk *chunk;
int count;
if (likely(!inode->i_fsnotify_marks))
return;
context = audit_context();
p = context->trees;
count = context->tree_count;
rcu_read_lock();
chunk = audit_tree_lookup(inode);
rcu_read_unlock();
if (!chunk)
return;
if (likely(put_tree_ref(context, chunk)))
return;
if (unlikely(!grow_tree_refs(context))) {
pr_warn("out of memory, audit has lost a tree reference\n");
audit_set_auditable(context);
audit_put_chunk(chunk);
unroll_tree_refs(context, p, count);
return;
}
put_tree_ref(context, chunk);
}
static void handle_path(const struct dentry *dentry)
{
struct audit_context *context;
struct audit_tree_refs *p;
const struct dentry *d, *parent;
struct audit_chunk *drop;
unsigned long seq;
int count;
context = audit_context();
p = context->trees;
count = context->tree_count;
retry:
drop = NULL;
d = dentry;
rcu_read_lock();
seq = read_seqbegin(&rename_lock);
for(;;) {
struct inode *inode = d_backing_inode(d);
if (inode && unlikely(inode->i_fsnotify_marks)) {
struct audit_chunk *chunk;
chunk = audit_tree_lookup(inode);
if (chunk) {
if (unlikely(!put_tree_ref(context, chunk))) {
drop = chunk;
break;
}
}
}
parent = d->d_parent;
if (parent == d)
break;
d = parent;
}
if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */
rcu_read_unlock();
if (!drop) {
/* just a race with rename */
unroll_tree_refs(context, p, count);
goto retry;
}
audit_put_chunk(drop);
if (grow_tree_refs(context)) {
/* OK, got more space */
unroll_tree_refs(context, p, count);
goto retry;
}
/* too bad */
pr_warn("out of memory, audit has lost a tree reference\n");
unroll_tree_refs(context, p, count);
audit_set_auditable(context);
return;
}
rcu_read_unlock();
}
static struct audit_names *audit_alloc_name(struct audit_context *context,
unsigned char type)
{
struct audit_names *aname;
if (context->name_count < AUDIT_NAMES) {
aname = &context->preallocated_names[context->name_count];
memset(aname, 0, sizeof(*aname));
} else {
aname = kzalloc(sizeof(*aname), GFP_NOFS);
if (!aname)
return NULL;
aname->should_free = true;
}
aname->ino = AUDIT_INO_UNSET;
aname->type = type;
list_add_tail(&aname->list, &context->names_list);
context->name_count++;
if (!context->pwd.dentry)
get_fs_pwd(current->fs, &context->pwd);
return aname;
}
/**
* __audit_reusename - fill out filename with info from existing entry
* @uptr: userland ptr to pathname
*
* Search the audit_names list for the current audit context. If there is an
* existing entry with a matching "uptr" then return the filename
* associated with that audit_name. If not, return NULL.
*/
struct filename *
__audit_reusename(const __user char *uptr)
{
struct audit_context *context = audit_context();
struct audit_names *n;
list_for_each_entry(n, &context->names_list, list) {
if (!n->name)
continue;
if (n->name->uptr == uptr) {
n->name->refcnt++;
return n->name;
}
}
return NULL;
}
/**
* __audit_getname - add a name to the list
* @name: name to add
*
* Add a name to the list of audit names for this context.
* Called from fs/namei.c:getname().
*/
void __audit_getname(struct filename *name)
{
struct audit_context *context = audit_context();
struct audit_names *n;
if (context->context == AUDIT_CTX_UNUSED)
return;
n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
if (!n)
return;
n->name = name;
n->name_len = AUDIT_NAME_FULL;
name->aname = n;
name->refcnt++;
}
static inline int audit_copy_fcaps(struct audit_names *name,
const struct dentry *dentry)
{
struct cpu_vfs_cap_data caps;
int rc;
if (!dentry)
return 0;
rc = get_vfs_caps_from_disk(&init_user_ns, dentry, &caps);
if (rc)
return rc;
name->fcap.permitted = caps.permitted;
name->fcap.inheritable = caps.inheritable;
name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
name->fcap.rootid = caps.rootid;
name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >>
VFS_CAP_REVISION_SHIFT;
return 0;
}
/* Copy inode data into an audit_names. */
static void audit_copy_inode(struct audit_names *name,
const struct dentry *dentry,
struct inode *inode, unsigned int flags)
{
name->ino = inode->i_ino;
name->dev = inode->i_sb->s_dev;
name->mode = inode->i_mode;
name->uid = inode->i_uid;
name->gid = inode->i_gid;
name->rdev = inode->i_rdev;
security_inode_getsecid(inode, &name->osid);
if (flags & AUDIT_INODE_NOEVAL) {
name->fcap_ver = -1;
return;
}
audit_copy_fcaps(name, dentry);
}
/**
* __audit_inode - store the inode and device from a lookup
* @name: name being audited
* @dentry: dentry being audited
* @flags: attributes for this particular entry
*/
void __audit_inode(struct filename *name, const struct dentry *dentry,
unsigned int flags)
{
struct audit_context *context = audit_context();
struct inode *inode = d_backing_inode(dentry);
struct audit_names *n;
bool parent = flags & AUDIT_INODE_PARENT;
struct audit_entry *e;
struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
int i;
if (context->context == AUDIT_CTX_UNUSED)
return;
rcu_read_lock();
list_for_each_entry_rcu(e, list, list) {
for (i = 0; i < e->rule.field_count; i++) {
struct audit_field *f = &e->rule.fields[i];
if (f->type == AUDIT_FSTYPE
&& audit_comparator(inode->i_sb->s_magic,
f->op, f->val)
&& e->rule.action == AUDIT_NEVER) {
rcu_read_unlock();
return;
}
}
}
rcu_read_unlock();
if (!name)
goto out_alloc;
/*
* If we have a pointer to an audit_names entry already, then we can
* just use it directly if the type is correct.
*/
n = name->aname;
if (n) {
if (parent) {
if (n->type == AUDIT_TYPE_PARENT ||
n->type == AUDIT_TYPE_UNKNOWN)
goto out;
} else {
if (n->type != AUDIT_TYPE_PARENT)
goto out;
}
}
list_for_each_entry_reverse(n, &context->names_list, list) {
if (n->ino) {
/* valid inode number, use that for the comparison */
if (n->ino != inode->i_ino ||
n->dev != inode->i_sb->s_dev)
continue;
} else if (n->name) {
/* inode number has not been set, check the name */
if (strcmp(n->name->name, name->name))
continue;
} else
/* no inode and no name (?!) ... this is odd ... */
continue;
/* match the correct record type */
if (parent) {
if (n->type == AUDIT_TYPE_PARENT ||
n->type == AUDIT_TYPE_UNKNOWN)
goto out;
} else {
if (n->type != AUDIT_TYPE_PARENT)
goto out;
}
}
out_alloc:
/* unable to find an entry with both a matching name and type */
n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
if (!n)
return;
if (name) {
n->name = name;
name->refcnt++;
}
out:
if (parent) {
n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
n->type = AUDIT_TYPE_PARENT;
if (flags & AUDIT_INODE_HIDDEN)
n->hidden = true;
} else {
n->name_len = AUDIT_NAME_FULL;
n->type = AUDIT_TYPE_NORMAL;
}
handle_path(dentry);
audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL);
}
void __audit_file(const struct file *file)
{
__audit_inode(NULL, file->f_path.dentry, 0);
}
/**
* __audit_inode_child - collect inode info for created/removed objects
* @parent: inode of dentry parent
* @dentry: dentry being audited
* @type: AUDIT_TYPE_* value that we're looking for
*
* For syscalls that create or remove filesystem objects, audit_inode
* can only collect information for the filesystem object's parent.
* This call updates the audit context with the child's information.
* Syscalls that create a new filesystem object must be hooked after
* the object is created. Syscalls that remove a filesystem object
* must be hooked prior, in order to capture the target inode during
* unsuccessful attempts.
*/
void __audit_inode_child(struct inode *parent,
const struct dentry *dentry,
const unsigned char type)
{
struct audit_context *context = audit_context();
struct inode *inode = d_backing_inode(dentry);
const struct qstr *dname = &dentry->d_name;
struct audit_names *n, *found_parent = NULL, *found_child = NULL;
struct audit_entry *e;
struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
int i;
if (context->context == AUDIT_CTX_UNUSED)
return;
rcu_read_lock();
list_for_each_entry_rcu(e, list, list) {
for (i = 0; i < e->rule.field_count; i++) {
struct audit_field *f = &e->rule.fields[i];
if (f->type == AUDIT_FSTYPE
&& audit_comparator(parent->i_sb->s_magic,
f->op, f->val)
&& e->rule.action == AUDIT_NEVER) {
rcu_read_unlock();
return;
}
}
}
rcu_read_unlock();
if (inode)
handle_one(inode);
/* look for a parent entry first */
list_for_each_entry(n, &context->names_list, list) {
if (!n->name ||
(n->type != AUDIT_TYPE_PARENT &&
n->type != AUDIT_TYPE_UNKNOWN))
continue;
if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev &&
!audit_compare_dname_path(dname,
n->name->name, n->name_len)) {
if (n->type == AUDIT_TYPE_UNKNOWN)
n->type = AUDIT_TYPE_PARENT;
found_parent = n;
break;
}
}
/* is there a matching child entry? */
list_for_each_entry(n, &context->names_list, list) {
/* can only match entries that have a name */
if (!n->name ||
(n->type != type && n->type != AUDIT_TYPE_UNKNOWN))
continue;
if (!strcmp(dname->name, n->name->name) ||
!audit_compare_dname_path(dname, n->name->name,
found_parent ?
found_parent->name_len :
AUDIT_NAME_FULL)) {
if (n->type == AUDIT_TYPE_UNKNOWN)
n->type = type;
found_child = n;
break;
}
}
if (!found_parent) {
/* create a new, "anonymous" parent record */
n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
if (!n)
return;
audit_copy_inode(n, NULL, parent, 0);
}
if (!found_child) {
found_child = audit_alloc_name(context, type);
if (!found_child)
return;
/* Re-use the name belonging to the slot for a matching parent
* directory. All names for this context are relinquished in
* audit_free_names() */
if (found_parent) {
found_child->name = found_parent->name;
found_child->name_len = AUDIT_NAME_FULL;
found_child->name->refcnt++;
}
}
if (inode)
audit_copy_inode(found_child, dentry, inode, 0);
else
found_child->ino = AUDIT_INO_UNSET;
}
EXPORT_SYMBOL_GPL(__audit_inode_child);
/**
* auditsc_get_stamp - get local copies of audit_context values
* @ctx: audit_context for the task
* @t: timespec64 to store time recorded in the audit_context
* @serial: serial value that is recorded in the audit_context
*
* Also sets the context as auditable.
*/
int auditsc_get_stamp(struct audit_context *ctx,
struct timespec64 *t, unsigned int *serial)
{
if (ctx->context == AUDIT_CTX_UNUSED)
return 0;
if (!ctx->serial)
ctx->serial = audit_serial();
t->tv_sec = ctx->ctime.tv_sec;
t->tv_nsec = ctx->ctime.tv_nsec;
*serial = ctx->serial;
if (!ctx->prio) {
ctx->prio = 1;
ctx->current_state = AUDIT_STATE_RECORD;
}
return 1;
}
/**
* __audit_mq_open - record audit data for a POSIX MQ open
* @oflag: open flag
* @mode: mode bits
* @attr: queue attributes
*
*/
void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
{
struct audit_context *context = audit_context();
if (attr)
memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
else
memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
context->mq_open.oflag = oflag;
context->mq_open.mode = mode;
context->type = AUDIT_MQ_OPEN;
}
/**
* __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
* @mqdes: MQ descriptor
* @msg_len: Message length
* @msg_prio: Message priority
* @abs_timeout: Message timeout in absolute time
*
*/
void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
const struct timespec64 *abs_timeout)
{
struct audit_context *context = audit_context();
struct timespec64 *p = &context->mq_sendrecv.abs_timeout;
if (abs_timeout)
memcpy(p, abs_timeout, sizeof(*p));
else
memset(p, 0, sizeof(*p));
context->mq_sendrecv.mqdes = mqdes;
context->mq_sendrecv.msg_len = msg_len;
context->mq_sendrecv.msg_prio = msg_prio;
context->type = AUDIT_MQ_SENDRECV;
}
/**
* __audit_mq_notify - record audit data for a POSIX MQ notify
* @mqdes: MQ descriptor
* @notification: Notification event
*
*/
void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
{
struct audit_context *context = audit_context();
if (notification)
context->mq_notify.sigev_signo = notification->sigev_signo;
else
context->mq_notify.sigev_signo = 0;
context->mq_notify.mqdes = mqdes;
context->type = AUDIT_MQ_NOTIFY;
}
/**
* __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
* @mqdes: MQ descriptor
* @mqstat: MQ flags
*
*/
void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
{
struct audit_context *context = audit_context();
context->mq_getsetattr.mqdes = mqdes;
context->mq_getsetattr.mqstat = *mqstat;
context->type = AUDIT_MQ_GETSETATTR;
}
/**
* __audit_ipc_obj - record audit data for ipc object
* @ipcp: ipc permissions
*
*/
void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
{
struct audit_context *context = audit_context();
context->ipc.uid = ipcp->uid;
context->ipc.gid = ipcp->gid;
context->ipc.mode = ipcp->mode;
context->ipc.has_perm = 0;
security_ipc_getsecid(ipcp, &context->ipc.osid);
context->type = AUDIT_IPC;
}
/**
* __audit_ipc_set_perm - record audit data for new ipc permissions
* @qbytes: msgq bytes
* @uid: msgq user id
* @gid: msgq group id
* @mode: msgq mode (permissions)
*
* Called only after audit_ipc_obj().
*/
void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
{
struct audit_context *context = audit_context();
context->ipc.qbytes = qbytes;
context->ipc.perm_uid = uid;
context->ipc.perm_gid = gid;
context->ipc.perm_mode = mode;
context->ipc.has_perm = 1;
}
void __audit_bprm(struct linux_binprm *bprm)
{
struct audit_context *context = audit_context();
context->type = AUDIT_EXECVE;
context->execve.argc = bprm->argc;
}
/**
* __audit_socketcall - record audit data for sys_socketcall
* @nargs: number of args, which should not be more than AUDITSC_ARGS.
* @args: args array
*
*/
int __audit_socketcall(int nargs, unsigned long *args)
{
struct audit_context *context = audit_context();
if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
return -EINVAL;
context->type = AUDIT_SOCKETCALL;
context->socketcall.nargs = nargs;
memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
return 0;
}
/**
* __audit_fd_pair - record audit data for pipe and socketpair
* @fd1: the first file descriptor
* @fd2: the second file descriptor
*
*/
void __audit_fd_pair(int fd1, int fd2)
{
struct audit_context *context = audit_context();
context->fds[0] = fd1;
context->fds[1] = fd2;
}
/**
* __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
* @len: data length in user space
* @a: data address in kernel space
*
* Returns 0 for success or NULL context or < 0 on error.
*/
int __audit_sockaddr(int len, void *a)
{
struct audit_context *context = audit_context();
if (!context->sockaddr) {
void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
if (!p)
return -ENOMEM;
context->sockaddr = p;
}
context->sockaddr_len = len;
memcpy(context->sockaddr, a, len);
return 0;
}
void __audit_ptrace(struct task_struct *t)
{
struct audit_context *context = audit_context();
context->target_pid = task_tgid_nr(t);
context->target_auid = audit_get_loginuid(t);
context->target_uid = task_uid(t);
context->target_sessionid = audit_get_sessionid(t);
security_task_getsecid_obj(t, &context->target_sid);
memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
}
/**
* audit_signal_info_syscall - record signal info for syscalls
* @t: task being signaled
*
* If the audit subsystem is being terminated, record the task (pid)
* and uid that is doing that.
*/
int audit_signal_info_syscall(struct task_struct *t)
{
struct audit_aux_data_pids *axp;
struct audit_context *ctx = audit_context();
kuid_t t_uid = task_uid(t);
if (!audit_signals || audit_dummy_context())
return 0;
/* optimize the common case by putting first signal recipient directly
* in audit_context */
if (!ctx->target_pid) {
ctx->target_pid = task_tgid_nr(t);
ctx->target_auid = audit_get_loginuid(t);
ctx->target_uid = t_uid;
ctx->target_sessionid = audit_get_sessionid(t);
security_task_getsecid_obj(t, &ctx->target_sid);
memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
return 0;
}
axp = (void *)ctx->aux_pids;
if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
if (!axp)
return -ENOMEM;
axp->d.type = AUDIT_OBJ_PID;
axp->d.next = ctx->aux_pids;
ctx->aux_pids = (void *)axp;
}
BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
axp->target_pid[axp->pid_count] = task_tgid_nr(t);
axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
axp->target_uid[axp->pid_count] = t_uid;
axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
security_task_getsecid_obj(t, &axp->target_sid[axp->pid_count]);
memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
axp->pid_count++;
return 0;
}
/**
* __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
* @bprm: pointer to the bprm being processed
* @new: the proposed new credentials
* @old: the old credentials
*
* Simply check if the proc already has the caps given by the file and if not
* store the priv escalation info for later auditing at the end of the syscall
*
* -Eric
*/
int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
const struct cred *new, const struct cred *old)
{
struct audit_aux_data_bprm_fcaps *ax;
struct audit_context *context = audit_context();
struct cpu_vfs_cap_data vcaps;
ax = kmalloc(sizeof(*ax), GFP_KERNEL);
if (!ax)
return -ENOMEM;
ax->d.type = AUDIT_BPRM_FCAPS;
ax->d.next = context->aux;
context->aux = (void *)ax;
get_vfs_caps_from_disk(&init_user_ns,
bprm->file->f_path.dentry, &vcaps);
ax->fcap.permitted = vcaps.permitted;
ax->fcap.inheritable = vcaps.inheritable;
ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
ax->fcap.rootid = vcaps.rootid;
ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
ax->old_pcap.permitted = old->cap_permitted;
ax->old_pcap.inheritable = old->cap_inheritable;
ax->old_pcap.effective = old->cap_effective;
ax->old_pcap.ambient = old->cap_ambient;
ax->new_pcap.permitted = new->cap_permitted;
ax->new_pcap.inheritable = new->cap_inheritable;
ax->new_pcap.effective = new->cap_effective;
ax->new_pcap.ambient = new->cap_ambient;
return 0;
}
/**
* __audit_log_capset - store information about the arguments to the capset syscall
* @new: the new credentials
* @old: the old (current) credentials
*
* Record the arguments userspace sent to sys_capset for later printing by the
* audit system if applicable
*/
void __audit_log_capset(const struct cred *new, const struct cred *old)
{
struct audit_context *context = audit_context();
context->capset.pid = task_tgid_nr(current);
context->capset.cap.effective = new->cap_effective;
context->capset.cap.inheritable = new->cap_effective;
context->capset.cap.permitted = new->cap_permitted;
context->capset.cap.ambient = new->cap_ambient;
context->type = AUDIT_CAPSET;
}
void __audit_mmap_fd(int fd, int flags)
{
struct audit_context *context = audit_context();
context->mmap.fd = fd;
context->mmap.flags = flags;
context->type = AUDIT_MMAP;
}
void __audit_openat2_how(struct open_how *how)
{
struct audit_context *context = audit_context();
context->openat2.flags = how->flags;
context->openat2.mode = how->mode;
context->openat2.resolve = how->resolve;
context->type = AUDIT_OPENAT2;
}
void __audit_log_kern_module(char *name)
{
struct audit_context *context = audit_context();
context->module.name = kstrdup(name, GFP_KERNEL);
if (!context->module.name)
audit_log_lost("out of memory in __audit_log_kern_module");
context->type = AUDIT_KERN_MODULE;
}
void __audit_fanotify(unsigned int response)
{
audit_log(audit_context(), GFP_KERNEL,
AUDIT_FANOTIFY, "resp=%u", response);
}
void __audit_tk_injoffset(struct timespec64 offset)
{
struct audit_context *context = audit_context();
/* only set type if not already set by NTP */
if (!context->type)
context->type = AUDIT_TIME_INJOFFSET;
memcpy(&context->time.tk_injoffset, &offset, sizeof(offset));
}
void __audit_ntp_log(const struct audit_ntp_data *ad)
{
struct audit_context *context = audit_context();
int type;
for (type = 0; type < AUDIT_NTP_NVALS; type++)
if (ad->vals[type].newval != ad->vals[type].oldval) {
/* unconditionally set type, overwriting TK */
context->type = AUDIT_TIME_ADJNTPVAL;
memcpy(&context->time.ntp_data, ad, sizeof(*ad));
break;
}
}
void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries,
enum audit_nfcfgop op, gfp_t gfp)
{
struct audit_buffer *ab;
char comm[sizeof(current->comm)];
ab = audit_log_start(audit_context(), gfp, AUDIT_NETFILTER_CFG);
if (!ab)
return;
audit_log_format(ab, "table=%s family=%u entries=%u op=%s",
name, af, nentries, audit_nfcfgs[op].s);
audit_log_format(ab, " pid=%u", task_pid_nr(current));
audit_log_task_context(ab); /* subj= */
audit_log_format(ab, " comm=");
audit_log_untrustedstring(ab, get_task_comm(comm, current));
audit_log_end(ab);
}
EXPORT_SYMBOL_GPL(__audit_log_nfcfg);
static void audit_log_task(struct audit_buffer *ab)
{
kuid_t auid, uid;
kgid_t gid;
unsigned int sessionid;
char comm[sizeof(current->comm)];
auid = audit_get_loginuid(current);
sessionid = audit_get_sessionid(current);
current_uid_gid(&uid, &gid);
audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
from_kuid(&init_user_ns, auid),
from_kuid(&init_user_ns, uid),
from_kgid(&init_user_ns, gid),
sessionid);
audit_log_task_context(ab);
audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current));
audit_log_untrustedstring(ab, get_task_comm(comm, current));
audit_log_d_path_exe(ab, current->mm);
}
/**
* audit_core_dumps - record information about processes that end abnormally
* @signr: signal value
*
* If a process ends with a core dump, something fishy is going on and we
* should record the event for investigation.
*/
void audit_core_dumps(long signr)
{
struct audit_buffer *ab;
if (!audit_enabled)
return;
if (signr == SIGQUIT) /* don't care for those */
return;
ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_ABEND);
if (unlikely(!ab))
return;
audit_log_task(ab);
audit_log_format(ab, " sig=%ld res=1", signr);
audit_log_end(ab);
}
/**
* audit_seccomp - record information about a seccomp action
* @syscall: syscall number
* @signr: signal value
* @code: the seccomp action
*
* Record the information associated with a seccomp action. Event filtering for
* seccomp actions that are not to be logged is done in seccomp_log().
* Therefore, this function forces auditing independent of the audit_enabled
* and dummy context state because seccomp actions should be logged even when
* audit is not in use.
*/
void audit_seccomp(unsigned long syscall, long signr, int code)
{
struct audit_buffer *ab;
ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_SECCOMP);
if (unlikely(!ab))
return;
audit_log_task(ab);
audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x",
signr, syscall_get_arch(current), syscall,
in_compat_syscall(), KSTK_EIP(current), code);
audit_log_end(ab);
}
void audit_seccomp_actions_logged(const char *names, const char *old_names,
int res)
{
struct audit_buffer *ab;
if (!audit_enabled)
return;
ab = audit_log_start(audit_context(), GFP_KERNEL,
AUDIT_CONFIG_CHANGE);
if (unlikely(!ab))
return;
audit_log_format(ab,
"op=seccomp-logging actions=%s old-actions=%s res=%d",
names, old_names, res);
audit_log_end(ab);
}
struct list_head *audit_killed_trees(void)
{
struct audit_context *ctx = audit_context();
if (likely(!ctx || ctx->context == AUDIT_CTX_UNUSED))
return NULL;
return &ctx->killed_trees;
}
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