2:57 p.m.
- PID will be reported in the relevant querying PID namespace.
- Refuse to change the current audit_pid if the new value does not
point to an existing process.
- Refuse to set the current audit_pid if the new value is not its own PID
(unless it is being unset).
- Convert audit_pid into the initial pid namespace for reports
(informed by ebiederman's 5bf431da)
Cc: "Eric W. Biederman" <ebiederm(a)xmission.com>
Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com>
---
kernel/audit.c | 40 ++++++++++++++++++++++++++++++----------
kernel/audit.h | 4 ++--
kernel/auditsc.c | 6 +++---
3 files changed, 35 insertions(+), 15 deletions(-)
diff --git a/kernel/audit.c b/kernel/audit.c
index f5ea718..015003c 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -95,7 +95,7 @@ static u32 audit_failure = AUDIT_FAIL_PRINTK;
* contains the pid of the auditd process and audit_nlk_portid contains
* the portid to use to send netlink messages to that process.
*/
-int audit_pid;
+struct pid *audit_pid;
static __u32 audit_nlk_portid;
/* If audit_rate_limit is non-zero, limit the rate of sending audit records
@@ -411,9 +411,12 @@ static void kauditd_send_skb(struct sk_buff *skb)
if (err < 0) {
BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */
if (audit_pid) {
- pr_err("*NO* daemon at audit_pid=%d\n", audit_pid);
+ struct pid *temp_pid = audit_pid;
+ pr_err("*NO* daemon at audit_pid=%d\n", pid_nr(audit_pid));
audit_log_lost("auditd disappeared\n");
- audit_pid = 0;
+ audit_pid = NULL;
+ smp_mb();
+ put_pid(temp_pid);
audit_sock = NULL;
}
/* we might get lucky and get this in the next auditd */
@@ -787,7 +790,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr
*nlh)
memset(&s, 0, sizeof(s));
s.enabled = audit_enabled;
s.failure = audit_failure;
- s.pid = audit_pid;
+ s.pid = pid_vnr(audit_pid);
s.rate_limit = audit_rate_limit;
s.backlog_limit = audit_backlog_limit;
s.lost = atomic_read(&audit_lost);
@@ -814,12 +817,29 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr
*nlh)
return err;
}
if (s.mask & AUDIT_STATUS_PID) {
- int new_pid = s.pid;
-
- if ((!new_pid) && (task_tgid_vnr(current) != audit_pid))
- return -EACCES;
+ struct pid *new_pid = NULL;
+
+ if (s.pid) {
+ rcu_read_lock();
+ new_pid = get_pid(task_tgid(find_task_by_vpid(s.pid)));
+ rcu_read_unlock();
+ if (!new_pid)
+ return -ESRCH;
+ /* check that non-zero pid it is trying to set
+ * is its own*/
+ if (new_pid != task_tgid(current)) {
+ put_pid(new_pid);
+ return -EPERM;
+ }
+ } else {
+ /* check that it isn't orphaning another process */
+ if (task_pid_vnr(current) != pid_vnr(audit_pid))
+ return -EACCES;
+ }
if (audit_enabled != AUDIT_OFF)
- audit_log_config_change("audit_pid", new_pid, audit_pid, 1);
+ audit_log_config_change("audit_pid", pid_nr(new_pid),
+ pid_nr(audit_pid), 1);
+ put_pid(audit_pid);
audit_pid = new_pid;
audit_nlk_portid = NETLINK_CB(skb).portid;
audit_sock = skb->sk;
@@ -1316,7 +1336,7 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx,
gfp_t gfp_mask,
return NULL;
if (gfp_mask & __GFP_WAIT) {
- if (audit_pid && audit_pid == current->pid)
+ if (audit_pid == task_tgid(current))
gfp_mask &= ~__GFP_WAIT;
else
reserve = 0;
diff --git a/kernel/audit.h b/kernel/audit.h
index 57cc64d..e0924bc 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -221,7 +221,7 @@ extern void audit_log_name(struct audit_context *context,
struct audit_names *n, struct path *path,
int record_num, int *call_panic);
-extern int audit_pid;
+extern struct pid *audit_pid;
#define AUDIT_INODE_BUCKETS 32
extern struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
@@ -318,7 +318,7 @@ extern u32 audit_sig_sid;
extern int __audit_signal_info(int sig, struct task_struct *t);
static inline int audit_signal_info(int sig, struct task_struct *t)
{
- if (unlikely((audit_pid && t->tgid == audit_pid) ||
+ if (unlikely((audit_pid && task_tgid(t) == audit_pid) ||
(audit_signals && !audit_dummy_context())))
return __audit_signal_info(sig, t);
return 0;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index b909715..a747afb 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -734,7 +734,7 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk,
struct audit_entry *e;
enum audit_state state;
- if (audit_pid && tsk->tgid == audit_pid)
+ if (audit_pid && task_tgid(tsk) == audit_pid)
return AUDIT_DISABLED;
rcu_read_lock();
@@ -795,7 +795,7 @@ void audit_filter_inodes(struct task_struct *tsk, struct audit_context
*ctx)
{
struct audit_names *n;
- if (audit_pid && tsk->tgid == audit_pid)
+ if (audit_pid && task_tgid(tsk) == audit_pid)
return;
rcu_read_lock();
@@ -2231,7 +2231,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
struct audit_context *ctx = tsk->audit_context;
kuid_t uid = current_uid(), t_uid = task_uid(t);
- if (audit_pid && t->tgid == audit_pid) {
+ if (audit_pid && task_tgid(t) == audit_pid) {
if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
audit_sig_pid = tsk->pid;
if (uid_valid(tsk->loginuid))
--
1.7.1