summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt14
-rw-r--r--MAINTAINERS1
-rw-r--r--fs/namei.c5
-rw-r--r--include/linux/audit.h6
-rw-r--r--kernel/audit.c108
-rw-r--r--kernel/audit.h3
-rw-r--r--kernel/audit_tree.c8
-rw-r--r--kernel/auditfilter.c5
-rw-r--r--kernel/auditsc.c22
9 files changed, 106 insertions, 66 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 3c87a69cffcb..7efed1ccddc9 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -389,15 +389,15 @@
Use software keyboard repeat
audit= [KNL] Enable the audit sub-system
- Format: { "0" | "1" } (0 = disabled, 1 = enabled)
- 0 - kernel audit is disabled and can not be enabled
- until the next reboot
+ Format: { "0" | "1" | "off" | "on" }
+ 0 | off - kernel audit is disabled and can not be
+ enabled until the next reboot
unset - kernel audit is initialized but disabled and
will be fully enabled by the userspace auditd.
- 1 - kernel audit is initialized and partially enabled,
- storing at most audit_backlog_limit messages in
- RAM until it is fully enabled by the userspace
- auditd.
+ 1 | on - kernel audit is initialized and partially
+ enabled, storing at most audit_backlog_limit
+ messages in RAM until it is fully enabled by the
+ userspace auditd.
Default: unset
audit_backlog_limit= [KNL] Set the audit queue size limit.
diff --git a/MAINTAINERS b/MAINTAINERS
index 881d328020df..f1be26eb7e80 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2504,7 +2504,6 @@ M: Paul Moore <paul@paul-moore.com>
M: Eric Paris <eparis@redhat.com>
L: linux-audit@redhat.com (moderated for non-subscribers)
W: https://github.com/linux-audit
-W: https://people.redhat.com/sgrubb/audit
T: git git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit.git
S: Supported
F: include/linux/audit.h
diff --git a/fs/namei.c b/fs/namei.c
index 5661da1972cd..a66ed5a1622a 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -929,7 +929,8 @@ static inline int may_follow_link(struct nameidata *nd)
if (nd->flags & LOOKUP_RCU)
return -ECHILD;
- audit_log_link_denied("follow_link", &nd->stack[0].link);
+ audit_inode(nd->name, nd->stack[0].link.dentry, 0);
+ audit_log_link_denied("follow_link");
return -EACCES;
}
@@ -995,7 +996,7 @@ static int may_linkat(struct path *link)
if (safe_hardlink_source(inode) || inode_owner_or_capable(inode))
return 0;
- audit_log_link_denied("linkat", link);
+ audit_log_link_denied("linkat");
return -EPERM;
}
diff --git a/include/linux/audit.h b/include/linux/audit.h
index af410d9fbf2d..75d5b031e802 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -146,8 +146,7 @@ extern void audit_log_d_path(struct audit_buffer *ab,
const struct path *path);
extern void audit_log_key(struct audit_buffer *ab,
char *key);
-extern void audit_log_link_denied(const char *operation,
- const struct path *link);
+extern void audit_log_link_denied(const char *operation);
extern void audit_log_lost(const char *message);
extern int audit_log_task_context(struct audit_buffer *ab);
@@ -194,8 +193,7 @@ static inline void audit_log_d_path(struct audit_buffer *ab,
{ }
static inline void audit_log_key(struct audit_buffer *ab, char *key)
{ }
-static inline void audit_log_link_denied(const char *string,
- const struct path *link)
+static inline void audit_log_link_denied(const char *string)
{ }
static inline int audit_log_task_context(struct audit_buffer *ab)
{
diff --git a/kernel/audit.c b/kernel/audit.c
index d97e8f0f73ca..670665c6e2a6 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -38,7 +38,8 @@
* 6) Support low-overhead kernel-based filtering to minimize the
* information that must be passed to user-space.
*
- * Example user-space utilities: http://people.redhat.com/sgrubb/audit/
+ * Audit userspace, documentation, tests, and bug/issue trackers:
+ * https://github.com/linux-audit
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -180,9 +181,21 @@ static char *audit_feature_names[2] = {
"loginuid_immutable",
};
-
-/* Serialize requests from userspace. */
-DEFINE_MUTEX(audit_cmd_mutex);
+/**
+ * struct audit_ctl_mutex - serialize requests from userspace
+ * @lock: the mutex used for locking
+ * @owner: the task which owns the lock
+ *
+ * Description:
+ * This is the lock struct used to ensure we only process userspace requests
+ * in an orderly fashion. We can't simply use a mutex/lock here because we
+ * need to track lock ownership so we don't end up blocking the lock owner in
+ * audit_log_start() or similar.
+ */
+static struct audit_ctl_mutex {
+ struct mutex lock;
+ void *owner;
+} audit_cmd_mutex;
/* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
* audit records. Since printk uses a 1024 byte buffer, this buffer
@@ -227,6 +240,36 @@ int auditd_test_task(struct task_struct *task)
}
/**
+ * audit_ctl_lock - Take the audit control lock
+ */
+void audit_ctl_lock(void)
+{
+ mutex_lock(&audit_cmd_mutex.lock);
+ audit_cmd_mutex.owner = current;
+}
+
+/**
+ * audit_ctl_unlock - Drop the audit control lock
+ */
+void audit_ctl_unlock(void)
+{
+ audit_cmd_mutex.owner = NULL;
+ mutex_unlock(&audit_cmd_mutex.lock);
+}
+
+/**
+ * audit_ctl_owner_current - Test to see if the current task owns the lock
+ *
+ * Description:
+ * Return true if the current task owns the audit control lock, false if it
+ * doesn't own the lock.
+ */
+static bool audit_ctl_owner_current(void)
+{
+ return (current == audit_cmd_mutex.owner);
+}
+
+/**
* auditd_pid_vnr - Return the auditd PID relative to the namespace
*
* Description:
@@ -860,8 +903,8 @@ int audit_send_list(void *_dest)
struct sock *sk = audit_get_sk(dest->net);
/* wait for parent to finish and send an ACK */
- mutex_lock(&audit_cmd_mutex);
- mutex_unlock(&audit_cmd_mutex);
+ audit_ctl_lock();
+ audit_ctl_unlock();
while ((skb = __skb_dequeue(&dest->q)) != NULL)
netlink_unicast(sk, skb, dest->portid, 0);
@@ -902,8 +945,8 @@ static int audit_send_reply_thread(void *arg)
struct audit_reply *reply = (struct audit_reply *)arg;
struct sock *sk = audit_get_sk(reply->net);
- mutex_lock(&audit_cmd_mutex);
- mutex_unlock(&audit_cmd_mutex);
+ audit_ctl_lock();
+ audit_ctl_unlock();
/* Ignore failure. It'll only happen if the sender goes away,
because our timeout is set to infinite. */
@@ -1058,6 +1101,8 @@ static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature
return;
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE);
+ if (!ab)
+ return;
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,
@@ -1466,7 +1511,7 @@ static void audit_receive(struct sk_buff *skb)
nlh = nlmsg_hdr(skb);
len = skb->len;
- mutex_lock(&audit_cmd_mutex);
+ audit_ctl_lock();
while (nlmsg_ok(nlh, len)) {
err = audit_receive_msg(skb, nlh);
/* if err or if this message says it wants a response */
@@ -1475,7 +1520,7 @@ static void audit_receive(struct sk_buff *skb)
nlh = nlmsg_next(nlh, &len);
}
- mutex_unlock(&audit_cmd_mutex);
+ audit_ctl_unlock();
}
/* Run custom bind function on netlink socket group connect or bind requests. */
@@ -1547,6 +1592,9 @@ static int __init audit_init(void)
for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
INIT_LIST_HEAD(&audit_inode_hash[i]);
+ mutex_init(&audit_cmd_mutex.lock);
+ audit_cmd_mutex.owner = NULL;
+
pr_info("initializing netlink subsys (%s)\n",
audit_default ? "enabled" : "disabled");
register_pernet_subsys(&audit_net_ops);
@@ -1567,19 +1615,26 @@ static int __init audit_init(void)
}
postcore_initcall(audit_init);
-/* Process kernel command-line parameter at boot time. audit=0 or audit=1. */
+/*
+ * Process kernel command-line parameter at boot time.
+ * audit={0|off} or audit={1|on}.
+ */
static int __init audit_enable(char *str)
{
- long val;
-
- if (kstrtol(str, 0, &val))
- panic("audit: invalid 'audit' parameter value (%s)\n", str);
- audit_default = (val ? AUDIT_ON : AUDIT_OFF);
+ if (!strcasecmp(str, "off") || !strcmp(str, "0"))
+ audit_default = AUDIT_OFF;
+ else if (!strcasecmp(str, "on") || !strcmp(str, "1"))
+ audit_default = AUDIT_ON;
+ else {
+ pr_err("audit: invalid 'audit' parameter value (%s)\n", str);
+ audit_default = AUDIT_ON;
+ }
if (audit_default == AUDIT_OFF)
audit_initialized = AUDIT_DISABLED;
if (audit_set_enabled(audit_default))
- panic("audit: error setting audit state (%d)\n", audit_default);
+ pr_err("audit: error setting audit state (%d)\n",
+ audit_default);
pr_info("%s\n", audit_default ?
"enabled (after initialization)" : "disabled (until reboot)");
@@ -1710,8 +1765,7 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
* using a PID anchored in the caller's namespace
* 2. generator holding the audit_cmd_mutex - we don't want to block
* while holding the mutex */
- if (!(auditd_test_task(current) ||
- (current == __mutex_owner(&audit_cmd_mutex)))) {
+ if (!(auditd_test_task(current) || audit_ctl_owner_current())) {
long stime = audit_backlog_wait_time;
while (audit_backlog_limit &&
@@ -2254,33 +2308,23 @@ EXPORT_SYMBOL(audit_log_task_info);
/**
* audit_log_link_denied - report a link restriction denial
* @operation: specific link operation
- * @link: the path that triggered the restriction
*/
-void audit_log_link_denied(const char *operation, const struct path *link)
+void audit_log_link_denied(const char *operation)
{
struct audit_buffer *ab;
- struct audit_names *name;
- name = kzalloc(sizeof(*name), GFP_NOFS);
- if (!name)
+ if (!audit_enabled || audit_dummy_context())
return;
/* Generate AUDIT_ANOM_LINK with subject, operation, outcome. */
ab = audit_log_start(current->audit_context, GFP_KERNEL,
AUDIT_ANOM_LINK);
if (!ab)
- goto out;
+ return;
audit_log_format(ab, "op=%s", operation);
audit_log_task_info(ab, current);
audit_log_format(ab, " res=0");
audit_log_end(ab);
-
- /* Generate AUDIT_PATH record with object. */
- name->type = AUDIT_TYPE_NORMAL;
- audit_copy_inode(name, link->dentry, d_backing_inode(link->dentry));
- audit_log_name(current->audit_context, name, link, 0, NULL);
-out:
- kfree(name);
}
/**
diff --git a/kernel/audit.h b/kernel/audit.h
index af5bc59487ed..214e14948370 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -341,4 +341,5 @@ extern struct list_head *audit_killed_trees(void);
#define audit_filter_inodes(t,c) AUDIT_DISABLED
#endif
-extern struct mutex audit_cmd_mutex;
+extern void audit_ctl_lock(void);
+extern void audit_ctl_unlock(void);
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index fd353120e0d9..67e6956c0b61 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -709,7 +709,7 @@ static int prune_tree_thread(void *unused)
schedule();
}
- mutex_lock(&audit_cmd_mutex);
+ audit_ctl_lock();
mutex_lock(&audit_filter_mutex);
while (!list_empty(&prune_list)) {
@@ -727,7 +727,7 @@ static int prune_tree_thread(void *unused)
}
mutex_unlock(&audit_filter_mutex);
- mutex_unlock(&audit_cmd_mutex);
+ audit_ctl_unlock();
}
return 0;
}
@@ -924,7 +924,7 @@ static void audit_schedule_prune(void)
*/
void audit_kill_trees(struct list_head *list)
{
- mutex_lock(&audit_cmd_mutex);
+ audit_ctl_lock();
mutex_lock(&audit_filter_mutex);
while (!list_empty(list)) {
@@ -942,7 +942,7 @@ void audit_kill_trees(struct list_head *list)
}
mutex_unlock(&audit_filter_mutex);
- mutex_unlock(&audit_cmd_mutex);
+ audit_ctl_unlock();
}
/*
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 4a1758adb222..d7a807e81451 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -258,8 +258,8 @@ static inline struct audit_entry *audit_to_entry_common(struct audit_rule_data *
goto exit_err;
#ifdef CONFIG_AUDITSYSCALL
case AUDIT_FILTER_ENTRY:
- if (rule->action == AUDIT_ALWAYS)
- goto exit_err;
+ pr_err("AUDIT_FILTER_ENTRY is deprecated\n");
+ goto exit_err;
case AUDIT_FILTER_EXIT:
case AUDIT_FILTER_TASK:
#endif
@@ -496,7 +496,6 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
if (!gid_valid(f->gid))
goto exit_free;
break;
- case AUDIT_SESSIONID:
case AUDIT_ARCH:
entry->rule.arch_f = f;
break;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index e80459f7e132..4e0a4ac803db 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1511,30 +1511,28 @@ void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
struct audit_context *context = tsk->audit_context;
enum audit_state state;
- if (!context)
+ if (!audit_enabled || !context)
return;
BUG_ON(context->in_syscall || context->name_count);
- if (!audit_enabled)
+ state = context->state;
+ if (state == AUDIT_DISABLED)
return;
+ context->dummy = !audit_n_rules;
+ if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
+ context->prio = 0;
+ if (auditd_test_task(tsk))
+ return;
+ }
+
context->arch = syscall_get_arch();
context->major = major;
context->argv[0] = a1;
context->argv[1] = a2;
context->argv[2] = a3;
context->argv[3] = a4;
-
- state = context->state;
- context->dummy = !audit_n_rules;
- if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
- context->prio = 0;
- state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
- }
- if (state == AUDIT_DISABLED)
- return;
-
context->serial = 0;
context->ctime = current_kernel_time64();
context->in_syscall = 1;
generated by cgit (git 2.34.1) at 2024-06-08 18:07:15 +0000