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Diffstat (limited to 'kernel/audit.c')
-rw-r--r--kernel/audit.c249
1 files changed, 173 insertions, 76 deletions
diff --git a/kernel/audit.c b/kernel/audit.c
index a7b16086d36..b7d3709cc45 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -126,6 +126,8 @@ static int audit_freelist_count;
static LIST_HEAD(audit_freelist);
static struct sk_buff_head audit_skb_queue;
+/* queue of skbs to send to auditd when/if it comes back */
+static struct sk_buff_head audit_skb_hold_queue;
static struct task_struct *kauditd_task;
static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
@@ -154,6 +156,11 @@ struct audit_buffer {
gfp_t gfp_mask;
};
+struct audit_reply {
+ int pid;
+ struct sk_buff *skb;
+};
+
static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
{
if (ab) {
@@ -252,14 +259,15 @@ void audit_log_lost(const char *message)
}
static int audit_log_config_change(char *function_name, int new, int old,
- uid_t loginuid, u32 sid, int allow_changes)
+ uid_t loginuid, u32 sessionid, u32 sid,
+ int allow_changes)
{
struct audit_buffer *ab;
int rc = 0;
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
- audit_log_format(ab, "%s=%d old=%d by auid=%u", function_name, new,
- old, loginuid);
+ audit_log_format(ab, "%s=%d old=%d auid=%u ses=%u", function_name, new,
+ old, loginuid, sessionid);
if (sid) {
char *ctx = NULL;
u32 len;
@@ -279,7 +287,8 @@ static int audit_log_config_change(char *function_name, int new, int old,
}
static int audit_do_config_change(char *function_name, int *to_change,
- int new, uid_t loginuid, u32 sid)
+ int new, uid_t loginuid, u32 sessionid,
+ u32 sid)
{
int allow_changes, rc = 0, old = *to_change;
@@ -290,8 +299,8 @@ static int audit_do_config_change(char *function_name, int *to_change,
allow_changes = 1;
if (audit_enabled != AUDIT_OFF) {
- rc = audit_log_config_change(function_name, new, old,
- loginuid, sid, allow_changes);
+ rc = audit_log_config_change(function_name, new, old, loginuid,
+ sessionid, sid, allow_changes);
if (rc)
allow_changes = 0;
}
@@ -305,26 +314,28 @@ static int audit_do_config_change(char *function_name, int *to_change,
return rc;
}
-static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sid)
+static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sessionid,
+ u32 sid)
{
return audit_do_config_change("audit_rate_limit", &audit_rate_limit,
- limit, loginuid, sid);
+ limit, loginuid, sessionid, sid);
}
-static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid)
+static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sessionid,
+ u32 sid)
{
return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit,
- limit, loginuid, sid);
+ limit, loginuid, sessionid, sid);
}
-static int audit_set_enabled(int state, uid_t loginuid, u32 sid)
+static int audit_set_enabled(int state, uid_t loginuid, u32 sessionid, u32 sid)
{
int rc;
if (state < AUDIT_OFF || state > AUDIT_LOCKED)
return -EINVAL;
rc = audit_do_config_change("audit_enabled", &audit_enabled, state,
- loginuid, sid);
+ loginuid, sessionid, sid);
if (!rc)
audit_ever_enabled |= !!state;
@@ -332,7 +343,7 @@ static int audit_set_enabled(int state, uid_t loginuid, u32 sid)
return rc;
}
-static int audit_set_failure(int state, uid_t loginuid, u32 sid)
+static int audit_set_failure(int state, uid_t loginuid, u32 sessionid, u32 sid)
{
if (state != AUDIT_FAIL_SILENT
&& state != AUDIT_FAIL_PRINTK
@@ -340,7 +351,43 @@ static int audit_set_failure(int state, uid_t loginuid, u32 sid)
return -EINVAL;
return audit_do_config_change("audit_failure", &audit_failure, state,
- loginuid, sid);
+ loginuid, sessionid, sid);
+}
+
+/*
+ * Queue skbs to be sent to auditd when/if it comes back. These skbs should
+ * already have been sent via prink/syslog and so if these messages are dropped
+ * it is not a huge concern since we already passed the audit_log_lost()
+ * notification and stuff. This is just nice to get audit messages during
+ * boot before auditd is running or messages generated while auditd is stopped.
+ * This only holds messages is audit_default is set, aka booting with audit=1
+ * or building your kernel that way.
+ */
+static void audit_hold_skb(struct sk_buff *skb)
+{
+ if (audit_default &&
+ skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit)
+ skb_queue_tail(&audit_skb_hold_queue, skb);
+ else
+ kfree_skb(skb);
+}
+
+static void kauditd_send_skb(struct sk_buff *skb)
+{
+ int err;
+ /* take a reference in case we can't send it and we want to hold it */
+ skb_get(skb);
+ err = netlink_unicast(audit_sock, skb, audit_nlk_pid, 0);
+ if (err < 0) {
+ BUG_ON(err != -ECONNREFUSED); /* Shoudn't happen */
+ printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
+ audit_log_lost("auditd dissapeared\n");
+ audit_pid = 0;
+ /* we might get lucky and get this in the next auditd */
+ audit_hold_skb(skb);
+ } else
+ /* drop the extra reference if sent ok */
+ kfree_skb(skb);
}
static int kauditd_thread(void *dummy)
@@ -349,24 +396,41 @@ static int kauditd_thread(void *dummy)
set_freezable();
while (!kthread_should_stop()) {
+ /*
+ * if auditd just started drain the queue of messages already
+ * sent to syslog/printk. remember loss here is ok. we already
+ * called audit_log_lost() if it didn't go out normally. so the
+ * race between the skb_dequeue and the next check for audit_pid
+ * doesn't matter.
+ *
+ * if you ever find kauditd to be too slow we can get a perf win
+ * by doing our own locking and keeping better track if there
+ * are messages in this queue. I don't see the need now, but
+ * in 5 years when I want to play with this again I'll see this
+ * note and still have no friggin idea what i'm thinking today.
+ */
+ if (audit_default && audit_pid) {
+ skb = skb_dequeue(&audit_skb_hold_queue);
+ if (unlikely(skb)) {
+ while (skb && audit_pid) {
+ kauditd_send_skb(skb);
+ skb = skb_dequeue(&audit_skb_hold_queue);
+ }
+ }
+ }
+
skb = skb_dequeue(&audit_skb_queue);
wake_up(&audit_backlog_wait);
if (skb) {
- if (audit_pid) {
- int err = netlink_unicast(audit_sock, skb, audit_nlk_pid, 0);
- if (err < 0) {
- BUG_ON(err != -ECONNREFUSED); /* Shoudn't happen */
- printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
- audit_log_lost("auditd dissapeared\n");
- audit_pid = 0;
- }
- } else {
+ if (audit_pid)
+ kauditd_send_skb(skb);
+ else {
if (printk_ratelimit())
- printk(KERN_NOTICE "%s\n", skb->data +
- NLMSG_SPACE(0));
+ printk(KERN_NOTICE "%s\n", skb->data + NLMSG_SPACE(0));
else
audit_log_lost("printk limit exceeded\n");
- kfree_skb(skb);
+
+ audit_hold_skb(skb);
}
} else {
DECLARE_WAITQUEUE(wait, current);
@@ -385,13 +449,13 @@ static int kauditd_thread(void *dummy)
return 0;
}
-static int audit_prepare_user_tty(pid_t pid, uid_t loginuid)
+static int audit_prepare_user_tty(pid_t pid, uid_t loginuid, u32 sessionid)
{
struct task_struct *tsk;
int err;
read_lock(&tasklist_lock);
- tsk = find_task_by_pid(pid);
+ tsk = find_task_by_vpid(pid);
err = -ESRCH;
if (!tsk)
goto out;
@@ -404,7 +468,7 @@ static int audit_prepare_user_tty(pid_t pid, uid_t loginuid)
if (err)
goto out;
- tty_audit_push_task(tsk, loginuid);
+ tty_audit_push_task(tsk, loginuid, sessionid);
out:
read_unlock(&tasklist_lock);
return err;
@@ -469,6 +533,19 @@ nlmsg_failure: /* Used by NLMSG_PUT */
return NULL;
}
+static int audit_send_reply_thread(void *arg)
+{
+ struct audit_reply *reply = (struct audit_reply *)arg;
+
+ 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);
+ kfree(reply);
+ return 0;
+}
/**
* audit_send_reply - send an audit reply message via netlink
* @pid: process id to send reply to
@@ -485,14 +562,26 @@ nlmsg_failure: /* Used by NLMSG_PUT */
void audit_send_reply(int pid, int seq, int type, int done, int multi,
void *payload, int size)
{
- struct sk_buff *skb;
+ struct sk_buff *skb;
+ struct task_struct *tsk;
+ struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
+ GFP_KERNEL);
+
+ if (!reply)
+ return;
+
skb = audit_make_reply(pid, seq, type, done, multi, payload, size);
if (!skb)
return;
- /* Ignore failure. It'll only happen if the sender goes away,
- because our timeout is set to infinite. */
- netlink_unicast(audit_sock, skb, pid, 0);
- return;
+
+ reply->pid = pid;
+ reply->skb = skb;
+
+ tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
+ if (IS_ERR(tsk)) {
+ kfree(reply);
+ kfree_skb(skb);
+ }
}
/*
@@ -534,7 +623,8 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
}
static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
- u32 pid, u32 uid, uid_t auid, u32 sid)
+ u32 pid, u32 uid, uid_t auid, u32 ses,
+ u32 sid)
{
int rc = 0;
char *ctx = NULL;
@@ -546,8 +636,8 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
}
*ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
- audit_log_format(*ab, "user pid=%d uid=%u auid=%u",
- pid, uid, auid);
+ audit_log_format(*ab, "user pid=%d uid=%u auid=%u ses=%u",
+ pid, uid, auid, ses);
if (sid) {
rc = security_secid_to_secctx(sid, &ctx, &len);
if (rc)
@@ -570,6 +660,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
struct audit_buffer *ab;
u16 msg_type = nlh->nlmsg_type;
uid_t loginuid; /* loginuid of sender */
+ u32 sessionid;
struct audit_sig_info *sig_data;
char *ctx = NULL;
u32 len;
@@ -591,6 +682,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
pid = NETLINK_CREDS(skb)->pid;
uid = NETLINK_CREDS(skb)->uid;
loginuid = NETLINK_CB(skb).loginuid;
+ sessionid = NETLINK_CB(skb).sessionid;
sid = NETLINK_CB(skb).sid;
seq = nlh->nlmsg_seq;
data = NLMSG_DATA(nlh);
@@ -613,12 +705,12 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
status_get = (struct audit_status *)data;
if (status_get->mask & AUDIT_STATUS_ENABLED) {
err = audit_set_enabled(status_get->enabled,
- loginuid, sid);
+ loginuid, sessionid, sid);
if (err < 0) return err;
}
if (status_get->mask & AUDIT_STATUS_FAILURE) {
err = audit_set_failure(status_get->failure,
- loginuid, sid);
+ loginuid, sessionid, sid);
if (err < 0) return err;
}
if (status_get->mask & AUDIT_STATUS_PID) {
@@ -627,17 +719,17 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
if (audit_enabled != AUDIT_OFF)
audit_log_config_change("audit_pid", new_pid,
audit_pid, loginuid,
- sid, 1);
+ sessionid, sid, 1);
audit_pid = new_pid;
audit_nlk_pid = NETLINK_CB(skb).pid;
}
if (status_get->mask & AUDIT_STATUS_RATE_LIMIT)
err = audit_set_rate_limit(status_get->rate_limit,
- loginuid, sid);
+ loginuid, sessionid, sid);
if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
err = audit_set_backlog_limit(status_get->backlog_limit,
- loginuid, sid);
+ loginuid, sessionid, sid);
break;
case AUDIT_USER:
case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
@@ -649,12 +741,13 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
if (err == 1) {
err = 0;
if (msg_type == AUDIT_USER_TTY) {
- err = audit_prepare_user_tty(pid, loginuid);
+ err = audit_prepare_user_tty(pid, loginuid,
+ sessionid);
if (err)
break;
}
audit_log_common_recv_msg(&ab, msg_type, pid, uid,
- loginuid, sid);
+ loginuid, sessionid, sid);
if (msg_type != AUDIT_USER_TTY)
audit_log_format(ab, " msg='%.1024s'",
@@ -664,8 +757,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
audit_log_format(ab, " msg=");
size = nlmsg_len(nlh);
- audit_log_n_untrustedstring(ab, size,
- data);
+ audit_log_n_untrustedstring(ab, data, size);
}
audit_set_pid(ab, pid);
audit_log_end(ab);
@@ -677,7 +769,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
return -EINVAL;
if (audit_enabled == AUDIT_LOCKED) {
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
- uid, loginuid, sid);
+ uid, loginuid, sessionid, sid);
audit_log_format(ab, " audit_enabled=%d res=0",
audit_enabled);
@@ -688,7 +780,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
case AUDIT_LIST:
err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
uid, seq, data, nlmsg_len(nlh),
- loginuid, sid);
+ loginuid, sessionid, sid);
break;
case AUDIT_ADD_RULE:
case AUDIT_DEL_RULE:
@@ -696,7 +788,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
return -EINVAL;
if (audit_enabled == AUDIT_LOCKED) {
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
- uid, loginuid, sid);
+ uid, loginuid, sessionid, sid);
audit_log_format(ab, " audit_enabled=%d res=0",
audit_enabled);
@@ -707,13 +799,13 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
case AUDIT_LIST_RULES:
err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
uid, seq, data, nlmsg_len(nlh),
- loginuid, sid);
+ loginuid, sessionid, sid);
break;
case AUDIT_TRIM:
audit_trim_trees();
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
- uid, loginuid, sid);
+ uid, loginuid, sessionid, sid);
audit_log_format(ab, " op=trim res=1");
audit_log_end(ab);
@@ -721,21 +813,21 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
case AUDIT_MAKE_EQUIV: {
void *bufp = data;
u32 sizes[2];
- size_t len = nlmsg_len(nlh);
+ size_t msglen = nlmsg_len(nlh);
char *old, *new;
err = -EINVAL;
- if (len < 2 * sizeof(u32))
+ if (msglen < 2 * sizeof(u32))
break;
memcpy(sizes, bufp, 2 * sizeof(u32));
bufp += 2 * sizeof(u32);
- len -= 2 * sizeof(u32);
- old = audit_unpack_string(&bufp, &len, sizes[0]);
+ msglen -= 2 * sizeof(u32);
+ old = audit_unpack_string(&bufp, &msglen, sizes[0]);
if (IS_ERR(old)) {
err = PTR_ERR(old);
break;
}
- new = audit_unpack_string(&bufp, &len, sizes[1]);
+ new = audit_unpack_string(&bufp, &msglen, sizes[1]);
if (IS_ERR(new)) {
err = PTR_ERR(new);
kfree(old);
@@ -745,7 +837,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
err = audit_tag_tree(old, new);
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
- uid, loginuid, sid);
+ uid, loginuid, sessionid, sid);
audit_log_format(ab, " op=make_equiv old=");
audit_log_untrustedstring(ab, old);
@@ -779,7 +871,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
struct task_struct *tsk;
read_lock(&tasklist_lock);
- tsk = find_task_by_pid(pid);
+ tsk = find_task_by_vpid(pid);
if (!tsk)
err = -ESRCH;
else {
@@ -802,7 +894,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
if (s->enabled != 0 && s->enabled != 1)
return -EINVAL;
read_lock(&tasklist_lock);
- tsk = find_task_by_pid(pid);
+ tsk = find_task_by_vpid(pid);
if (!tsk)
err = -ESRCH;
else {
@@ -877,6 +969,7 @@ static int __init audit_init(void)
audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
skb_queue_head_init(&audit_skb_queue);
+ skb_queue_head_init(&audit_skb_hold_queue);
audit_initialized = 1;
audit_enabled = audit_default;
audit_ever_enabled |= !!audit_default;
@@ -1199,7 +1292,7 @@ void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
* This function will take the passed buf and convert it into a string of
* ascii hex digits. The new string is placed onto the skb.
*/
-void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf,
+void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
size_t len)
{
int i, avail, new_len;
@@ -1235,8 +1328,8 @@ void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf,
* Format a string of no more than slen characters into the audit buffer,
* enclosed in quote marks.
*/
-static void audit_log_n_string(struct audit_buffer *ab, size_t slen,
- const char *string)
+void audit_log_n_string(struct audit_buffer *ab, const char *string,
+ size_t slen)
{
int avail, new_len;
unsigned char *ptr;
@@ -1292,13 +1385,13 @@ int audit_string_contains_control(const char *string, size_t len)
* The caller specifies the number of characters in the string to log, which may
* or may not be the entire string.
*/
-void audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len,
- const char *string)
+void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string,
+ size_t len)
{
if (audit_string_contains_control(string, len))
- audit_log_hex(ab, string, len);
+ audit_log_n_hex(ab, string, len);
else
- audit_log_n_string(ab, len, string);
+ audit_log_n_string(ab, string, len);
}
/**
@@ -1311,7 +1404,7 @@ void audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len,
*/
void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
{
- audit_log_n_untrustedstring(ab, strlen(string), string);
+ audit_log_n_untrustedstring(ab, string, strlen(string));
}
/* This is a helper-function to print the escaped d_path */
@@ -1355,19 +1448,23 @@ void audit_log_end(struct audit_buffer *ab)
audit_log_lost("rate limit exceeded");
} else {
struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
+ nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0);
+
if (audit_pid) {
- nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0);
skb_queue_tail(&audit_skb_queue, ab->skb);
- ab->skb = NULL;
wake_up_interruptible(&kauditd_wait);
- } else if (nlh->nlmsg_type != AUDIT_EOE) {
- if (printk_ratelimit()) {
- printk(KERN_NOTICE "type=%d %s\n",
- nlh->nlmsg_type,
- ab->skb->data + NLMSG_SPACE(0));
- } else
- audit_log_lost("printk limit exceeded\n");
+ } else {
+ if (nlh->nlmsg_type != AUDIT_EOE) {
+ if (printk_ratelimit()) {
+ printk(KERN_NOTICE "type=%d %s\n",
+ nlh->nlmsg_type,
+ ab->skb->data + NLMSG_SPACE(0));
+ } else
+ audit_log_lost("printk limit exceeded\n");
+ }
+ audit_hold_skb(ab->skb);
}
+ ab->skb = NULL;
}
audit_buffer_free(ab);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-29 05:01:09 +0000