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Diffstat (limited to 'kernel/audit.c')
-rw-r--r--kernel/audit.c624
1 files changed, 463 insertions, 161 deletions
diff --git a/kernel/audit.c b/kernel/audit.c
index 7b0e23a740c..3ef2e0e797e 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -41,8 +41,10 @@
* Example user-space utilities: http://people.redhat.com/sgrubb/audit/
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <linux/init.h>
-#include <asm/types.h>
+#include <linux/types.h>
#include <linux/atomic.h>
#include <linux/mm.h>
#include <linux/export.h>
@@ -60,10 +62,10 @@
#ifdef CONFIG_SECURITY
#include <linux/security.h>
#endif
-#include <net/netlink.h>
#include <linux/freezer.h>
#include <linux/tty.h>
#include <linux/pid_namespace.h>
+#include <net/netns/generic.h>
#include "audit.h"
@@ -77,16 +79,16 @@ static int audit_initialized;
#define AUDIT_OFF 0
#define AUDIT_ON 1
#define AUDIT_LOCKED 2
-int audit_enabled;
-int audit_ever_enabled;
+u32 audit_enabled;
+u32 audit_ever_enabled;
EXPORT_SYMBOL_GPL(audit_enabled);
/* Default state when kernel boots without any parameters. */
-static int audit_default;
+static u32 audit_default;
/* If auditing cannot proceed, audit_failure selects what happens. */
-static int audit_failure = AUDIT_FAIL_PRINTK;
+static u32 audit_failure = AUDIT_FAIL_PRINTK;
/*
* If audit records are to be written to the netlink socket, audit_pid
@@ -94,17 +96,19 @@ static int audit_failure = AUDIT_FAIL_PRINTK;
* the portid to use to send netlink messages to that process.
*/
int audit_pid;
-static int audit_nlk_portid;
+static __u32 audit_nlk_portid;
/* If audit_rate_limit is non-zero, limit the rate of sending audit records
* to that number per second. This prevents DoS attacks, but results in
* audit records being dropped. */
-static int audit_rate_limit;
+static u32 audit_rate_limit;
-/* Number of outstanding audit_buffers allowed. */
-static int audit_backlog_limit = 64;
-static int audit_backlog_wait_time = 60 * HZ;
-static int audit_backlog_wait_overflow = 0;
+/* Number of outstanding audit_buffers allowed.
+ * When set to zero, this means unlimited. */
+static u32 audit_backlog_limit = 64;
+#define AUDIT_BACKLOG_WAIT_TIME (60 * HZ)
+static u32 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
+static u32 audit_backlog_wait_overflow = 0;
/* The identity of the user shutting down the audit system. */
kuid_t audit_sig_uid = INVALID_UID;
@@ -122,6 +126,7 @@ static atomic_t audit_lost = ATOMIC_INIT(0);
/* The netlink socket. */
static struct sock *audit_sock;
+int audit_net_id;
/* Hash for inode-based rules */
struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
@@ -140,6 +145,17 @@ static struct task_struct *kauditd_task;
static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
+static struct audit_features af = {.vers = AUDIT_FEATURE_VERSION,
+ .mask = -1,
+ .features = 0,
+ .lock = 0,};
+
+static char *audit_feature_names[2] = {
+ "only_unset_loginuid",
+ "loginuid_immutable",
+};
+
+
/* Serialize requests from userspace. */
DEFINE_MUTEX(audit_cmd_mutex);
@@ -165,27 +181,27 @@ struct audit_buffer {
};
struct audit_reply {
- int pid;
+ __u32 portid;
+ struct net *net;
struct sk_buff *skb;
};
-static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
+static void audit_set_portid(struct audit_buffer *ab, __u32 portid)
{
if (ab) {
struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
- nlh->nlmsg_pid = pid;
+ nlh->nlmsg_pid = portid;
}
}
void audit_panic(const char *message)
{
- switch (audit_failure)
- {
+ switch (audit_failure) {
case AUDIT_FAIL_SILENT:
break;
case AUDIT_FAIL_PRINTK:
if (printk_ratelimit())
- printk(KERN_ERR "audit: %s\n", message);
+ pr_err("%s\n", message);
break;
case AUDIT_FAIL_PANIC:
/* test audit_pid since printk is always losey, why bother? */
@@ -256,9 +272,7 @@ void audit_log_lost(const char *message)
if (print) {
if (printk_ratelimit())
- printk(KERN_WARNING
- "audit: audit_lost=%d audit_rate_limit=%d "
- "audit_backlog_limit=%d\n",
+ pr_warn("audit_lost=%u audit_rate_limit=%u audit_backlog_limit=%u\n",
atomic_read(&audit_lost),
audit_rate_limit,
audit_backlog_limit);
@@ -266,7 +280,7 @@ void audit_log_lost(const char *message)
}
}
-static int audit_log_config_change(char *function_name, int new, int old,
+static int audit_log_config_change(char *function_name, u32 new, u32 old,
int allow_changes)
{
struct audit_buffer *ab;
@@ -275,7 +289,7 @@ static int audit_log_config_change(char *function_name, int new, int old,
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
if (unlikely(!ab))
return rc;
- audit_log_format(ab, "%s=%d old=%d", function_name, new, old);
+ audit_log_format(ab, "%s=%u old=%u", function_name, new, old);
audit_log_session_info(ab);
rc = audit_log_task_context(ab);
if (rc)
@@ -285,9 +299,10 @@ static int audit_log_config_change(char *function_name, int new, int old,
return rc;
}
-static int audit_do_config_change(char *function_name, int *to_change, int new)
+static int audit_do_config_change(char *function_name, u32 *to_change, u32 new)
{
- int allow_changes, rc = 0, old = *to_change;
+ int allow_changes, rc = 0;
+ u32 old = *to_change;
/* check if we are locked */
if (audit_enabled == AUDIT_LOCKED)
@@ -310,17 +325,23 @@ static int audit_do_config_change(char *function_name, int *to_change, int new)
return rc;
}
-static int audit_set_rate_limit(int limit)
+static int audit_set_rate_limit(u32 limit)
{
return audit_do_config_change("audit_rate_limit", &audit_rate_limit, limit);
}
-static int audit_set_backlog_limit(int limit)
+static int audit_set_backlog_limit(u32 limit)
{
return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit, limit);
}
-static int audit_set_enabled(int state)
+static int audit_set_backlog_wait_time(u32 timeout)
+{
+ return audit_do_config_change("audit_backlog_wait_time",
+ &audit_backlog_wait_time, timeout);
+}
+
+static int audit_set_enabled(u32 state)
{
int rc;
if (state < AUDIT_OFF || state > AUDIT_LOCKED)
@@ -333,7 +354,7 @@ static int audit_set_enabled(int state)
return rc;
}
-static int audit_set_failure(int state)
+static int audit_set_failure(u32 state)
{
if (state != AUDIT_FAIL_SILENT
&& state != AUDIT_FAIL_PRINTK
@@ -355,7 +376,8 @@ static int audit_set_failure(int state)
static void audit_hold_skb(struct sk_buff *skb)
{
if (audit_default &&
- skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit)
+ (!audit_backlog_limit ||
+ skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit))
skb_queue_tail(&audit_skb_hold_queue, skb);
else
kfree_skb(skb);
@@ -372,9 +394,9 @@ static void audit_printk_skb(struct sk_buff *skb)
if (nlh->nlmsg_type != AUDIT_EOE) {
if (printk_ratelimit())
- printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, data);
+ pr_notice("type=%d %s\n", nlh->nlmsg_type, data);
else
- audit_log_lost("printk limit exceeded\n");
+ audit_log_lost("printk limit exceeded");
}
audit_hold_skb(skb);
@@ -388,9 +410,12 @@ static void kauditd_send_skb(struct sk_buff *skb)
err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0);
if (err < 0) {
BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */
- printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
- audit_log_lost("auditd disappeared\n");
- audit_pid = 0;
+ if (audit_pid) {
+ pr_err("*NO* daemon at audit_pid=%d\n", audit_pid);
+ audit_log_lost("auditd disappeared");
+ audit_pid = 0;
+ audit_sock = NULL;
+ }
/* we might get lucky and get this in the next auditd */
audit_hold_skb(skb);
} else
@@ -399,6 +424,38 @@ static void kauditd_send_skb(struct sk_buff *skb)
}
/*
+ * kauditd_send_multicast_skb - send the skb to multicast userspace listeners
+ *
+ * This function doesn't consume an skb as might be expected since it has to
+ * copy it anyways.
+ */
+static void kauditd_send_multicast_skb(struct sk_buff *skb)
+{
+ struct sk_buff *copy;
+ struct audit_net *aunet = net_generic(&init_net, audit_net_id);
+ struct sock *sock = aunet->nlsk;
+
+ if (!netlink_has_listeners(sock, AUDIT_NLGRP_READLOG))
+ return;
+
+ /*
+ * The seemingly wasteful skb_copy() rather than bumping the refcount
+ * using skb_get() is necessary because non-standard mods are made to
+ * the skb by the original kaudit unicast socket send routine. The
+ * existing auditd daemon assumes this breakage. Fixing this would
+ * require co-ordinating a change in the established protocol between
+ * the kaudit kernel subsystem and the auditd userspace code. There is
+ * no reason for new multicast clients to continue with this
+ * non-compliance.
+ */
+ copy = skb_copy(skb, GFP_KERNEL);
+ if (!copy)
+ return;
+
+ nlmsg_multicast(sock, copy, 0, AUDIT_NLGRP_READLOG, GFP_KERNEL);
+}
+
+/*
* flush_hold_queue - empty the hold queue if auditd appears
*
* If auditd just started, drain the queue of messages already
@@ -447,8 +504,10 @@ static int kauditd_thread(void *dummy)
flush_hold_queue();
skb = skb_dequeue(&audit_skb_queue);
- wake_up(&audit_backlog_wait);
+
if (skb) {
+ if (skb_queue_len(&audit_skb_queue) <= audit_backlog_limit)
+ wake_up(&audit_backlog_wait);
if (audit_pid)
kauditd_send_skb(skb);
else
@@ -472,22 +531,24 @@ static int kauditd_thread(void *dummy)
int audit_send_list(void *_dest)
{
struct audit_netlink_list *dest = _dest;
- int pid = dest->pid;
struct sk_buff *skb;
+ struct net *net = dest->net;
+ struct audit_net *aunet = net_generic(net, audit_net_id);
/* wait for parent to finish and send an ACK */
mutex_lock(&audit_cmd_mutex);
mutex_unlock(&audit_cmd_mutex);
while ((skb = __skb_dequeue(&dest->q)) != NULL)
- netlink_unicast(audit_sock, skb, pid, 0);
+ netlink_unicast(aunet->nlsk, skb, dest->portid, 0);
+ put_net(net);
kfree(dest);
return 0;
}
-struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
+struct sk_buff *audit_make_reply(__u32 portid, int seq, int type, int done,
int multi, const void *payload, int size)
{
struct sk_buff *skb;
@@ -500,7 +561,7 @@ struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
if (!skb)
return NULL;
- nlh = nlmsg_put(skb, pid, seq, t, size, flags);
+ nlh = nlmsg_put(skb, portid, seq, t, size, flags);
if (!nlh)
goto out_kfree_skb;
data = nlmsg_data(nlh);
@@ -515,19 +576,22 @@ out_kfree_skb:
static int audit_send_reply_thread(void *arg)
{
struct audit_reply *reply = (struct audit_reply *)arg;
+ struct net *net = reply->net;
+ struct audit_net *aunet = net_generic(net, audit_net_id);
mutex_lock(&audit_cmd_mutex);
mutex_unlock(&audit_cmd_mutex);
/* Ignore failure. It'll only happen if the sender goes away,
because our timeout is set to infinite. */
- netlink_unicast(audit_sock, reply->skb, reply->pid, 0);
+ netlink_unicast(aunet->nlsk , reply->skb, reply->portid, 0);
+ put_net(net);
kfree(reply);
return 0;
}
/**
* audit_send_reply - send an audit reply message via netlink
- * @pid: process id to send reply to
+ * @request_skb: skb of request we are replying to (used to target the reply)
* @seq: sequence number
* @type: audit message type
* @done: done (last) flag
@@ -535,12 +599,14 @@ static int audit_send_reply_thread(void *arg)
* @payload: payload data
* @size: payload size
*
- * Allocates an skb, builds the netlink message, and sends it to the pid.
+ * Allocates an skb, builds the netlink message, and sends it to the port id.
* No failure notifications.
*/
-static void audit_send_reply(int pid, int seq, int type, int done, int multi,
- const void *payload, int size)
+static void audit_send_reply(struct sk_buff *request_skb, int seq, int type, int done,
+ int multi, const void *payload, int size)
{
+ u32 portid = NETLINK_CB(request_skb).portid;
+ struct net *net = sock_net(NETLINK_CB(request_skb).sk);
struct sk_buff *skb;
struct task_struct *tsk;
struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
@@ -549,11 +615,12 @@ static void audit_send_reply(int pid, int seq, int type, int done, int multi,
if (!reply)
return;
- skb = audit_make_reply(pid, seq, type, done, multi, payload, size);
+ skb = audit_make_reply(portid, seq, type, done, multi, payload, size);
if (!skb)
goto out;
- reply->pid = pid;
+ reply->net = get_net(net);
+ reply->portid = portid;
reply->skb = skb;
tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
@@ -572,10 +639,19 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
{
int err = 0;
- /* Only support the initial namespaces for now. */
- if ((current_user_ns() != &init_user_ns) ||
- (task_active_pid_ns(current) != &init_pid_ns))
- return -EPERM;
+ /* Only support initial user namespace for now. */
+ /*
+ * We return ECONNREFUSED because it tricks userspace into thinking
+ * that audit was not configured into the kernel. Lots of users
+ * configure their PAM stack (because that's what the distro does)
+ * to reject login if unable to send messages to audit. If we return
+ * ECONNREFUSED the PAM stack thinks the kernel does not have audit
+ * configured in and will let login proceed. If we return EPERM
+ * userspace will reject all logins. This should be removed when we
+ * support non init namespaces!!
+ */
+ if (current_user_ns() != &init_user_ns)
+ return -ECONNREFUSED;
switch (msg_type) {
case AUDIT_LIST:
@@ -584,6 +660,8 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
return -EOPNOTSUPP;
case AUDIT_GET:
case AUDIT_SET:
+ case AUDIT_GET_FEATURE:
+ case AUDIT_SET_FEATURE:
case AUDIT_LIST_RULES:
case AUDIT_ADD_RULE:
case AUDIT_DEL_RULE:
@@ -592,13 +670,18 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
case AUDIT_TTY_SET:
case AUDIT_TRIM:
case AUDIT_MAKE_EQUIV:
- if (!capable(CAP_AUDIT_CONTROL))
+ /* Only support auditd and auditctl in initial pid namespace
+ * for now. */
+ if ((task_active_pid_ns(current) != &init_pid_ns))
+ return -EPERM;
+
+ if (!netlink_capable(skb, CAP_AUDIT_CONTROL))
err = -EPERM;
break;
case AUDIT_USER:
case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
- if (!capable(CAP_AUDIT_WRITE))
+ if (!netlink_capable(skb, CAP_AUDIT_WRITE))
err = -EPERM;
break;
default: /* bad msg */
@@ -612,8 +695,9 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
{
int rc = 0;
uid_t uid = from_kuid(&init_user_ns, current_uid());
+ pid_t pid = task_tgid_nr(current);
- if (!audit_enabled) {
+ if (!audit_enabled && msg_type != AUDIT_USER_AVC) {
*ab = NULL;
return rc;
}
@@ -621,18 +705,108 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
*ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
if (unlikely(!*ab))
return rc;
- audit_log_format(*ab, "pid=%d uid=%u", task_tgid_vnr(current), uid);
+ audit_log_format(*ab, "pid=%d uid=%u", pid, uid);
audit_log_session_info(*ab);
audit_log_task_context(*ab);
return rc;
}
+int is_audit_feature_set(int i)
+{
+ return af.features & AUDIT_FEATURE_TO_MASK(i);
+}
+
+
+static int audit_get_feature(struct sk_buff *skb)
+{
+ u32 seq;
+
+ seq = nlmsg_hdr(skb)->nlmsg_seq;
+
+ audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &af, sizeof(af));
+
+ return 0;
+}
+
+static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature,
+ u32 old_lock, u32 new_lock, int res)
+{
+ struct audit_buffer *ab;
+
+ if (audit_enabled == AUDIT_OFF)
+ return;
+
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE);
+ audit_log_task_info(ab, current);
+ audit_log_format(ab, "feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d",
+ audit_feature_names[which], !!old_feature, !!new_feature,
+ !!old_lock, !!new_lock, res);
+ audit_log_end(ab);
+}
+
+static int audit_set_feature(struct sk_buff *skb)
+{
+ struct audit_features *uaf;
+ int i;
+
+ BUILD_BUG_ON(AUDIT_LAST_FEATURE + 1 > sizeof(audit_feature_names)/sizeof(audit_feature_names[0]));
+ uaf = nlmsg_data(nlmsg_hdr(skb));
+
+ /* if there is ever a version 2 we should handle that here */
+
+ for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
+ u32 feature = AUDIT_FEATURE_TO_MASK(i);
+ u32 old_feature, new_feature, old_lock, new_lock;
+
+ /* if we are not changing this feature, move along */
+ if (!(feature & uaf->mask))
+ continue;
+
+ old_feature = af.features & feature;
+ new_feature = uaf->features & feature;
+ new_lock = (uaf->lock | af.lock) & feature;
+ old_lock = af.lock & feature;
+
+ /* are we changing a locked feature? */
+ if (old_lock && (new_feature != old_feature)) {
+ audit_log_feature_change(i, old_feature, new_feature,
+ old_lock, new_lock, 0);
+ return -EPERM;
+ }
+ }
+ /* nothing invalid, do the changes */
+ for (i = 0; i <= AUDIT_LAST_FEATURE; i++) {
+ u32 feature = AUDIT_FEATURE_TO_MASK(i);
+ u32 old_feature, new_feature, old_lock, new_lock;
+
+ /* if we are not changing this feature, move along */
+ if (!(feature & uaf->mask))
+ continue;
+
+ old_feature = af.features & feature;
+ new_feature = uaf->features & feature;
+ old_lock = af.lock & feature;
+ new_lock = (uaf->lock | af.lock) & feature;
+
+ if (new_feature != old_feature)
+ audit_log_feature_change(i, old_feature, new_feature,
+ old_lock, new_lock, 1);
+
+ if (new_feature)
+ af.features |= feature;
+ else
+ af.features &= ~feature;
+ af.lock |= new_lock;
+ }
+
+ return 0;
+}
+
static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
{
u32 seq;
void *data;
- struct audit_status *status_get, status_set;
int err;
struct audit_buffer *ab;
u16 msg_type = nlh->nlmsg_type;
@@ -658,46 +832,78 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
data = nlmsg_data(nlh);
switch (msg_type) {
- case AUDIT_GET:
- status_set.enabled = audit_enabled;
- status_set.failure = audit_failure;
- status_set.pid = audit_pid;
- status_set.rate_limit = audit_rate_limit;
- status_set.backlog_limit = audit_backlog_limit;
- status_set.lost = atomic_read(&audit_lost);
- status_set.backlog = skb_queue_len(&audit_skb_queue);
- audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_GET, 0, 0,
- &status_set, sizeof(status_set));
+ case AUDIT_GET: {
+ struct audit_status s;
+ memset(&s, 0, sizeof(s));
+ s.enabled = audit_enabled;
+ s.failure = audit_failure;
+ s.pid = audit_pid;
+ s.rate_limit = audit_rate_limit;
+ s.backlog_limit = audit_backlog_limit;
+ s.lost = atomic_read(&audit_lost);
+ s.backlog = skb_queue_len(&audit_skb_queue);
+ s.version = AUDIT_VERSION_LATEST;
+ s.backlog_wait_time = audit_backlog_wait_time;
+ audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &s, sizeof(s));
break;
- case AUDIT_SET:
- if (nlh->nlmsg_len < sizeof(struct audit_status))
- return -EINVAL;
- status_get = (struct audit_status *)data;
- if (status_get->mask & AUDIT_STATUS_ENABLED) {
- err = audit_set_enabled(status_get->enabled);
+ }
+ case AUDIT_SET: {
+ struct audit_status s;
+ memset(&s, 0, sizeof(s));
+ /* guard against past and future API changes */
+ memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
+ if (s.mask & AUDIT_STATUS_ENABLED) {
+ err = audit_set_enabled(s.enabled);
if (err < 0)
return err;
}
- if (status_get->mask & AUDIT_STATUS_FAILURE) {
- err = audit_set_failure(status_get->failure);
+ if (s.mask & AUDIT_STATUS_FAILURE) {
+ err = audit_set_failure(s.failure);
if (err < 0)
return err;
}
- if (status_get->mask & AUDIT_STATUS_PID) {
- int new_pid = status_get->pid;
+ if (s.mask & AUDIT_STATUS_PID) {
+ int new_pid = s.pid;
+ if ((!new_pid) && (task_tgid_vnr(current) != audit_pid))
+ return -EACCES;
if (audit_enabled != AUDIT_OFF)
audit_log_config_change("audit_pid", new_pid, audit_pid, 1);
audit_pid = new_pid;
audit_nlk_portid = NETLINK_CB(skb).portid;
+ audit_sock = skb->sk;
+ }
+ if (s.mask & AUDIT_STATUS_RATE_LIMIT) {
+ err = audit_set_rate_limit(s.rate_limit);
+ if (err < 0)
+ return err;
+ }
+ if (s.mask & AUDIT_STATUS_BACKLOG_LIMIT) {
+ err = audit_set_backlog_limit(s.backlog_limit);
+ if (err < 0)
+ return err;
}
- if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) {
- err = audit_set_rate_limit(status_get->rate_limit);
+ if (s.mask & AUDIT_STATUS_BACKLOG_WAIT_TIME) {
+ if (sizeof(s) > (size_t)nlh->nlmsg_len)
+ return -EINVAL;
+ if (s.backlog_wait_time < 0 ||
+ s.backlog_wait_time > 10*AUDIT_BACKLOG_WAIT_TIME)
+ return -EINVAL;
+ err = audit_set_backlog_wait_time(s.backlog_wait_time);
if (err < 0)
return err;
}
- if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
- err = audit_set_backlog_limit(status_get->backlog_limit);
+ break;
+ }
+ case AUDIT_GET_FEATURE:
+ err = audit_get_feature(skb);
+ if (err)
+ return err;
+ break;
+ case AUDIT_SET_FEATURE:
+ err = audit_set_feature(skb);
+ if (err)
+ return err;
break;
case AUDIT_USER:
case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
@@ -706,16 +912,18 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
return 0;
err = audit_filter_user(msg_type);
- if (err == 1) {
+ if (err == 1) { /* match or error */
err = 0;
if (msg_type == AUDIT_USER_TTY) {
err = tty_audit_push_current();
if (err)
break;
}
+ mutex_unlock(&audit_cmd_mutex);
audit_log_common_recv_msg(&ab, msg_type);
if (msg_type != AUDIT_USER_TTY)
- audit_log_format(ab, " msg='%.1024s'",
+ audit_log_format(ab, " msg='%.*s'",
+ AUDIT_MESSAGE_TEXT_MAX,
(char *)data);
else {
int size;
@@ -727,8 +935,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
size--;
audit_log_n_untrustedstring(ab, data, size);
}
- audit_set_pid(ab, NETLINK_CB(skb).portid);
+ audit_set_portid(ab, NETLINK_CB(skb).portid);
audit_log_end(ab);
+ mutex_lock(&audit_cmd_mutex);
}
break;
case AUDIT_ADD_RULE:
@@ -741,11 +950,12 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
audit_log_end(ab);
return -EPERM;
}
- /* fallthrough */
- case AUDIT_LIST_RULES:
- err = audit_receive_filter(msg_type, NETLINK_CB(skb).portid,
+ err = audit_rule_change(msg_type, NETLINK_CB(skb).portid,
seq, data, nlmsg_len(nlh));
break;
+ case AUDIT_LIST_RULES:
+ err = audit_list_rules_send(skb, seq);
+ break;
case AUDIT_TRIM:
audit_trim_trees();
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
@@ -809,8 +1019,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
memcpy(sig_data->ctx, ctx, len);
security_release_secctx(ctx, len);
}
- audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_SIGNAL_INFO,
- 0, 0, sig_data, sizeof(*sig_data) + len);
+ audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
+ sig_data, sizeof(*sig_data) + len);
kfree(sig_data);
break;
case AUDIT_TTY_GET: {
@@ -818,29 +1028,41 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
struct task_struct *tsk = current;
spin_lock(&tsk->sighand->siglock);
- s.enabled = tsk->signal->audit_tty != 0;
+ s.enabled = tsk->signal->audit_tty;
s.log_passwd = tsk->signal->audit_tty_log_passwd;
spin_unlock(&tsk->sighand->siglock);
- audit_send_reply(NETLINK_CB(skb).portid, seq,
- AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
+ audit_send_reply(skb, seq, AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
break;
}
case AUDIT_TTY_SET: {
- struct audit_tty_status s;
+ struct audit_tty_status s, old;
struct task_struct *tsk = current;
+ struct audit_buffer *ab;
memset(&s, 0, sizeof(s));
/* guard against past and future API changes */
- memcpy(&s, data, min(sizeof(s), (size_t)nlh->nlmsg_len));
+ memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
+ /* check if new data is valid */
if ((s.enabled != 0 && s.enabled != 1) ||
(s.log_passwd != 0 && s.log_passwd != 1))
- return -EINVAL;
+ err = -EINVAL;
spin_lock(&tsk->sighand->siglock);
- tsk->signal->audit_tty = s.enabled;
- tsk->signal->audit_tty_log_passwd = s.log_passwd;
+ old.enabled = tsk->signal->audit_tty;
+ old.log_passwd = tsk->signal->audit_tty_log_passwd;
+ if (!err) {
+ tsk->signal->audit_tty = s.enabled;
+ tsk->signal->audit_tty_log_passwd = s.log_passwd;
+ }
spin_unlock(&tsk->sighand->siglock);
+
+ audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
+ audit_log_format(ab, " op=tty_set old-enabled=%d new-enabled=%d"
+ " old-log_passwd=%d new-log_passwd=%d res=%d",
+ old.enabled, s.enabled, old.log_passwd,
+ s.log_passwd, !err);
+ audit_log_end(ab);
break;
}
default:
@@ -886,24 +1108,67 @@ static void audit_receive(struct sk_buff *skb)
mutex_unlock(&audit_cmd_mutex);
}
-/* Initialize audit support at boot time. */
-static int __init audit_init(void)
+/* Run custom bind function on netlink socket group connect or bind requests. */
+static int audit_bind(int group)
+{
+ if (!capable(CAP_AUDIT_READ))
+ return -EPERM;
+
+ return 0;
+}
+
+static int __net_init audit_net_init(struct net *net)
{
- int i;
struct netlink_kernel_cfg cfg = {
.input = audit_receive,
+ .bind = audit_bind,
+ .flags = NL_CFG_F_NONROOT_RECV,
+ .groups = AUDIT_NLGRP_MAX,
};
+ struct audit_net *aunet = net_generic(net, audit_net_id);
+
+ aunet->nlsk = netlink_kernel_create(net, NETLINK_AUDIT, &cfg);
+ if (aunet->nlsk == NULL) {
+ audit_panic("cannot initialize netlink socket in namespace");
+ return -ENOMEM;
+ }
+ aunet->nlsk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
+ return 0;
+}
+
+static void __net_exit audit_net_exit(struct net *net)
+{
+ struct audit_net *aunet = net_generic(net, audit_net_id);
+ struct sock *sock = aunet->nlsk;
+ if (sock == audit_sock) {
+ audit_pid = 0;
+ audit_sock = NULL;
+ }
+
+ RCU_INIT_POINTER(aunet->nlsk, NULL);
+ synchronize_net();
+ netlink_kernel_release(sock);
+}
+
+static struct pernet_operations audit_net_ops __net_initdata = {
+ .init = audit_net_init,
+ .exit = audit_net_exit,
+ .id = &audit_net_id,
+ .size = sizeof(struct audit_net),
+};
+
+/* Initialize audit support at boot time. */
+static int __init audit_init(void)
+{
+ int i;
+
if (audit_initialized == AUDIT_DISABLED)
return 0;
- printk(KERN_INFO "audit: initializing netlink socket (%s)\n",
- audit_default ? "enabled" : "disabled");
- audit_sock = netlink_kernel_create(&init_net, NETLINK_AUDIT, &cfg);
- if (!audit_sock)
- audit_panic("cannot initialize netlink socket");
- else
- audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
+ pr_info("initializing netlink subsys (%s)\n",
+ audit_default ? "enabled" : "disabled");
+ register_pernet_subsys(&audit_net_ops);
skb_queue_head_init(&audit_skb_queue);
skb_queue_head_init(&audit_skb_hold_queue);
@@ -927,22 +1192,32 @@ static int __init audit_enable(char *str)
if (!audit_default)
audit_initialized = AUDIT_DISABLED;
- printk(KERN_INFO "audit: %s", audit_default ? "enabled" : "disabled");
+ pr_info("%s\n", audit_default ?
+ "enabled (after initialization)" : "disabled (until reboot)");
- if (audit_initialized == AUDIT_INITIALIZED) {
- audit_enabled = audit_default;
- audit_ever_enabled |= !!audit_default;
- } else if (audit_initialized == AUDIT_UNINITIALIZED) {
- printk(" (after initialization)");
- } else {
- printk(" (until reboot)");
+ return 1;
+}
+__setup("audit=", audit_enable);
+
+/* Process kernel command-line parameter at boot time.
+ * audit_backlog_limit=<n> */
+static int __init audit_backlog_limit_set(char *str)
+{
+ u32 audit_backlog_limit_arg;
+
+ pr_info("audit_backlog_limit: ");
+ if (kstrtouint(str, 0, &audit_backlog_limit_arg)) {
+ pr_cont("using default of %u, unable to parse %s\n",
+ audit_backlog_limit, str);
+ return 1;
}
- printk("\n");
+
+ audit_backlog_limit = audit_backlog_limit_arg;
+ pr_cont("%d\n", audit_backlog_limit);
return 1;
}
-
-__setup("audit=", audit_enable);
+__setup("audit_backlog_limit=", audit_backlog_limit_set);
static void audit_buffer_free(struct audit_buffer *ab)
{
@@ -1053,26 +1328,21 @@ static inline void audit_get_stamp(struct audit_context *ctx,
/*
* Wait for auditd to drain the queue a little
*/
-static void wait_for_auditd(unsigned long sleep_time)
+static long wait_for_auditd(long sleep_time)
{
DECLARE_WAITQUEUE(wait, current);
set_current_state(TASK_UNINTERRUPTIBLE);
- add_wait_queue(&audit_backlog_wait, &wait);
+ add_wait_queue_exclusive(&audit_backlog_wait, &wait);
if (audit_backlog_limit &&
skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
- schedule_timeout(sleep_time);
+ sleep_time = schedule_timeout(sleep_time);
__set_current_state(TASK_RUNNING);
remove_wait_queue(&audit_backlog_wait, &wait);
-}
-/* Obtain an audit buffer. This routine does locking to obtain the
- * audit buffer, but then no locking is required for calls to
- * audit_log_*format. If the tsk is a task that is currently in a
- * syscall, then the syscall is marked as auditable and an audit record
- * will be written at syscall exit. If there is no associated task, tsk
- * should be NULL. */
+ return sleep_time;
+}
/**
* audit_log_start - obtain an audit buffer
@@ -1095,7 +1365,8 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
struct audit_buffer *ab = NULL;
struct timespec t;
unsigned int uninitialized_var(serial);
- int reserve;
+ int reserve = 5; /* Allow atomic callers to go up to five
+ entries over the normal backlog limit */
unsigned long timeout_start = jiffies;
if (audit_initialized != AUDIT_INITIALIZED)
@@ -1104,36 +1375,37 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
if (unlikely(audit_filter_type(type)))
return NULL;
- if (gfp_mask & __GFP_WAIT)
- reserve = 0;
- else
- reserve = 5; /* Allow atomic callers to go up to five
- entries over the normal backlog limit */
+ if (gfp_mask & __GFP_WAIT) {
+ if (audit_pid && audit_pid == current->pid)
+ gfp_mask &= ~__GFP_WAIT;
+ else
+ reserve = 0;
+ }
while (audit_backlog_limit
&& skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) {
- unsigned long sleep_time;
+ long sleep_time;
- sleep_time = timeout_start + audit_backlog_wait_time -
- jiffies;
- if ((long)sleep_time > 0) {
- wait_for_auditd(sleep_time);
- continue;
+ sleep_time = timeout_start + audit_backlog_wait_time - jiffies;
+ if (sleep_time > 0) {
+ sleep_time = wait_for_auditd(sleep_time);
+ if (sleep_time > 0)
+ continue;
}
}
if (audit_rate_check() && printk_ratelimit())
- printk(KERN_WARNING
- "audit: audit_backlog=%d > "
- "audit_backlog_limit=%d\n",
- skb_queue_len(&audit_skb_queue),
- audit_backlog_limit);
+ pr_warn("audit_backlog=%d > audit_backlog_limit=%d\n",
+ skb_queue_len(&audit_skb_queue),
+ audit_backlog_limit);
audit_log_lost("backlog limit exceeded");
audit_backlog_wait_time = audit_backlog_wait_overflow;
wake_up(&audit_backlog_wait);
return NULL;
}
+ audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
+
ab = audit_buffer_alloc(ctx, gfp_mask, type);
if (!ab) {
audit_log_lost("out of memory in audit_log_start");
@@ -1251,7 +1523,6 @@ void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
int i, avail, new_len;
unsigned char *ptr;
struct sk_buff *skb;
- static const unsigned char *hex = "0123456789ABCDEF";
if (!ab)
return;
@@ -1269,10 +1540,8 @@ void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
}
ptr = skb_tail_pointer(skb);
- for (i=0; i<len; i++) {
- *ptr++ = hex[(buf[i] & 0xF0)>>4]; /* Upper nibble */
- *ptr++ = hex[buf[i] & 0x0F]; /* Lower nibble */
- }
+ for (i = 0; i < len; i++)
+ ptr = hex_byte_pack_upper(ptr, buf[i]);
*ptr = 0;
skb_put(skb, len << 1); /* new string is twice the old string */
}
@@ -1386,10 +1655,10 @@ void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
void audit_log_session_info(struct audit_buffer *ab)
{
- u32 sessionid = audit_get_sessionid(current);
+ unsigned int sessionid = audit_get_sessionid(current);
uid_t auid = from_kuid(&init_user_ns, audit_get_loginuid(current));
- audit_log_format(ab, " auid=%u ses=%u\n", auid, sessionid);
+ audit_log_format(ab, " auid=%u ses=%u", auid, sessionid);
}
void audit_log_key(struct audit_buffer *ab, char *key)
@@ -1536,6 +1805,26 @@ void audit_log_name(struct audit_context *context, struct audit_names *n,
}
}
+ /* log the audit_names record type */
+ audit_log_format(ab, " nametype=");
+ switch(n->type) {
+ case AUDIT_TYPE_NORMAL:
+ audit_log_format(ab, "NORMAL");
+ break;
+ case AUDIT_TYPE_PARENT:
+ audit_log_format(ab, "PARENT");
+ break;
+ case AUDIT_TYPE_CHILD_DELETE:
+ audit_log_format(ab, "DELETE");
+ break;
+ case AUDIT_TYPE_CHILD_CREATE:
+ audit_log_format(ab, "CREATE");
+ break;
+ default:
+ audit_log_format(ab, "UNKNOWN");
+ break;
+ }
+
audit_log_fcaps(ab, n);
audit_log_end(ab);
}
@@ -1589,11 +1878,11 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
spin_unlock_irq(&tsk->sighand->siglock);
audit_log_format(ab,
- " ppid=%ld pid=%d auid=%u uid=%u gid=%u"
+ " ppid=%d pid=%d auid=%u uid=%u gid=%u"
" euid=%u suid=%u fsuid=%u"
- " egid=%u sgid=%u fsgid=%u ses=%u tty=%s",
- sys_getppid(),
- tsk->pid,
+ " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
+ task_ppid_nr(tsk),
+ task_pid_nr(tsk),
from_kuid(&init_user_ns, audit_get_loginuid(tsk)),
from_kuid(&init_user_ns, cred->uid),
from_kgid(&init_user_ns, cred->gid),
@@ -1603,7 +1892,7 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
from_kgid(&init_user_ns, cred->egid),
from_kgid(&init_user_ns, cred->sgid),
from_kgid(&init_user_ns, cred->fsgid),
- audit_get_sessionid(tsk), tty);
+ tty, audit_get_sessionid(tsk));
get_task_comm(name, tsk);
audit_log_format(ab, " comm=");
@@ -1614,7 +1903,8 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
if (mm->exe_file)
audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
up_read(&mm->mmap_sem);
- }
+ } else
+ audit_log_format(ab, " exe=(null)");
audit_log_task_context(ab);
}
EXPORT_SYMBOL(audit_log_task_info);
@@ -1655,10 +1945,10 @@ out:
* audit_log_end - end one audit record
* @ab: the audit_buffer
*
- * The netlink_* functions cannot be called inside an irq context, so
- * the audit buffer is placed on a queue and a tasklet is scheduled to
- * remove them from the queue outside the irq context. May be called in
- * any context.
+ * netlink_unicast() cannot be called inside an irq context because it blocks
+ * (last arg, flags, is not set to MSG_DONTWAIT), so the audit buffer is placed
+ * on a queue and a tasklet is scheduled to remove them from the queue outside
+ * the irq context. May be called in any context.
*/
void audit_log_end(struct audit_buffer *ab)
{
@@ -1668,6 +1958,18 @@ void audit_log_end(struct audit_buffer *ab)
audit_log_lost("rate limit exceeded");
} else {
struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
+
+ kauditd_send_multicast_skb(ab->skb);
+
+ /*
+ * The original kaudit unicast socket sends up messages with
+ * nlmsg_len set to the payload length rather than the entire
+ * message length. This breaks the standard set by netlink.
+ * The existing auditd daemon assumes this breakage. Fixing
+ * this would require co-ordinating a change in the established
+ * protocol between the kaudit kernel subsystem and the auditd
+ * userspace code.
+ */
nlh->nlmsg_len = ab->skb->len - NLMSG_HDRLEN;
if (audit_pid) {
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-04 01:27:20 +0000