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authorLinus Torvalds <torvalds@linux-foundation.org>2013-11-21 19:18:14 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-11-21 19:18:14 -0800
commit3eaded86ac3e7f00fb3eeb8162d89e9a34e42fb0 (patch)
tree4c48b9f1739dcb034186956bf39908803b524154 /kernel
parent527d1511310a89650000081869260394e20c7013 (diff)
parent9175c9d2aed528800175ef81c90569d00d23f9be (diff)
Merge git://git.infradead.org/users/eparis/audit
Pull audit updates from Eric Paris: "Nothing amazing. Formatting, small bug fixes, couple of fixes where we didn't get records due to some old VFS changes, and a change to how we collect execve info..." Fixed conflict in fs/exec.c as per Eric and linux-next. * git://git.infradead.org/users/eparis/audit: (28 commits) audit: fix type of sessionid in audit_set_loginuid() audit: call audit_bprm() only once to add AUDIT_EXECVE information audit: move audit_aux_data_execve contents into audit_context union audit: remove unused envc member of audit_aux_data_execve audit: Kill the unused struct audit_aux_data_capset audit: do not reject all AUDIT_INODE filter types audit: suppress stock memalloc failure warnings since already managed audit: log the audit_names record type audit: add child record before the create to handle case where create fails audit: use given values in tty_audit enable api audit: use nlmsg_len() to get message payload length audit: use memset instead of trying to initialize field by field audit: fix info leak in AUDIT_GET requests audit: update AUDIT_INODE filter rule to comparator function audit: audit feature to set loginuid immutable audit: audit feature to only allow unsetting the loginuid audit: allow unsetting the loginuid (with priv) audit: remove CONFIG_AUDIT_LOGINUID_IMMUTABLE audit: loginuid functions coding style selinux: apply selinux checks on new audit message types ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/audit.c153
-rw-r--r--kernel/audit.h3
-rw-r--r--kernel/auditfilter.c3
-rw-r--r--kernel/auditsc.c133
4 files changed, 210 insertions, 82 deletions
diff --git a/kernel/audit.c b/kernel/audit.c
index 7b0e23a740ce..906ae5a0233a 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -60,7 +60,6 @@
#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>
@@ -140,6 +139,17 @@ 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);
@@ -584,6 +594,8 @@ 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:
@@ -613,7 +625,7 @@ 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());
- if (!audit_enabled) {
+ if (!audit_enabled && msg_type != AUDIT_USER_AVC) {
*ab = NULL;
return rc;
}
@@ -628,6 +640,94 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
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(NETLINK_CB(skb).portid, 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;
+
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE);
+ audit_log_format(ab, "feature=%s new=%d old=%d old_lock=%d new_lock=%d 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 ((af.lock & feature) && (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;
@@ -659,6 +759,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
switch (msg_type) {
case AUDIT_GET:
+ memset(&status_set, 0, sizeof(status_set));
status_set.enabled = audit_enabled;
status_set.failure = audit_failure;
status_set.pid = audit_pid;
@@ -670,7 +771,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
&status_set, sizeof(status_set));
break;
case AUDIT_SET:
- if (nlh->nlmsg_len < sizeof(struct audit_status))
+ if (nlmsg_len(nlh) < sizeof(struct audit_status))
return -EINVAL;
status_get = (struct audit_status *)data;
if (status_get->mask & AUDIT_STATUS_ENABLED) {
@@ -699,6 +800,16 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
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:
case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
@@ -715,7 +826,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
}
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;
@@ -818,7 +930,7 @@ 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);
@@ -832,7 +944,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
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)));
if ((s.enabled != 0 && s.enabled != 1) ||
(s.log_passwd != 0 && s.log_passwd != 1))
return -EINVAL;
@@ -1067,13 +1179,6 @@ static void wait_for_auditd(unsigned long sleep_time)
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. */
-
/**
* audit_log_start - obtain an audit buffer
* @ctx: audit_context (may be NULL)
@@ -1389,7 +1494,7 @@ void audit_log_session_info(struct audit_buffer *ab)
u32 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 +1641,26 @@ 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);
}
diff --git a/kernel/audit.h b/kernel/audit.h
index 123c9b7c3979..b779642b29af 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -197,6 +197,9 @@ struct audit_context {
int fd;
int flags;
} mmap;
+ struct {
+ int argc;
+ } execve;
};
int fds[2];
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index f7aee8be7fb2..51f3fd4c1ed3 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -343,6 +343,7 @@ static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
case AUDIT_DEVMINOR:
case AUDIT_EXIT:
case AUDIT_SUCCESS:
+ case AUDIT_INODE:
/* bit ops are only useful on syscall args */
if (f->op == Audit_bitmask || f->op == Audit_bittest)
return -EINVAL;
@@ -423,7 +424,7 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
f->lsm_rule = NULL;
/* Support legacy tests for a valid loginuid */
- if ((f->type == AUDIT_LOGINUID) && (f->val == ~0U)) {
+ if ((f->type == AUDIT_LOGINUID) && (f->val == AUDIT_UID_UNSET)) {
f->type = AUDIT_LOGINUID_SET;
f->val = 0;
}
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 9845cb32b60a..90594c9f7552 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -95,13 +95,6 @@ struct audit_aux_data {
/* Number of target pids per aux struct. */
#define AUDIT_AUX_PIDS 16
-struct audit_aux_data_execve {
- struct audit_aux_data d;
- int argc;
- int envc;
- struct mm_struct *mm;
-};
-
struct audit_aux_data_pids {
struct audit_aux_data d;
pid_t target_pid[AUDIT_AUX_PIDS];
@@ -121,12 +114,6 @@ struct audit_aux_data_bprm_fcaps {
struct audit_cap_data new_pcap;
};
-struct audit_aux_data_capset {
- struct audit_aux_data d;
- pid_t pid;
- struct audit_cap_data cap;
-};
-
struct audit_tree_refs {
struct audit_tree_refs *next;
struct audit_chunk *c[31];
@@ -566,7 +553,7 @@ static int audit_filter_rules(struct task_struct *tsk,
break;
case AUDIT_INODE:
if (name)
- result = (name->ino == f->val);
+ 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)) {
@@ -943,8 +930,10 @@ int audit_alloc(struct task_struct *tsk)
return 0; /* Return if not auditing. */
state = audit_filter_task(tsk, &key);
- if (state == AUDIT_DISABLED)
+ if (state == AUDIT_DISABLED) {
+ clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
return 0;
+ }
if (!(context = audit_alloc_context(state))) {
kfree(key);
@@ -1149,20 +1138,16 @@ static int audit_log_single_execve_arg(struct audit_context *context,
}
static void audit_log_execve_info(struct audit_context *context,
- struct audit_buffer **ab,
- struct audit_aux_data_execve *axi)
+ struct audit_buffer **ab)
{
int i, len;
size_t len_sent = 0;
const char __user *p;
char *buf;
- if (axi->mm != current->mm)
- return; /* execve failed, no additional info */
-
- p = (const char __user *)axi->mm->arg_start;
+ p = (const char __user *)current->mm->arg_start;
- audit_log_format(*ab, "argc=%d", axi->argc);
+ audit_log_format(*ab, "argc=%d", context->execve.argc);
/*
* we need some kernel buffer to hold the userspace args. Just
@@ -1176,7 +1161,7 @@ static void audit_log_execve_info(struct audit_context *context,
return;
}
- for (i = 0; i < axi->argc; i++) {
+ for (i = 0; i < context->execve.argc; i++) {
len = audit_log_single_execve_arg(context, ab, i,
&len_sent, p, buf);
if (len <= 0)
@@ -1279,6 +1264,9 @@ static void show_special(struct audit_context *context, int *call_panic)
audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
context->mmap.flags);
break; }
+ case AUDIT_EXECVE: {
+ audit_log_execve_info(context, &ab);
+ break; }
}
audit_log_end(ab);
}
@@ -1325,11 +1313,6 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
switch (aux->type) {
- case AUDIT_EXECVE: {
- struct audit_aux_data_execve *axi = (void *)aux;
- audit_log_execve_info(context, &ab, axi);
- break; }
-
case AUDIT_BPRM_FCAPS: {
struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
audit_log_format(ab, "fver=%x", axs->fcap_ver);
@@ -1964,6 +1947,43 @@ int auditsc_get_stamp(struct audit_context *ctx,
/* global counter which is incremented every time something logs in */
static atomic_t session_id = ATOMIC_INIT(0);
+static int audit_set_loginuid_perm(kuid_t loginuid)
+{
+ /* if we are unset, we don't need privs */
+ if (!audit_loginuid_set(current))
+ return 0;
+ /* if AUDIT_FEATURE_LOGINUID_IMMUTABLE means never ever allow a change*/
+ if (is_audit_feature_set(AUDIT_FEATURE_LOGINUID_IMMUTABLE))
+ return -EPERM;
+ /* it is set, you need permission */
+ if (!capable(CAP_AUDIT_CONTROL))
+ return -EPERM;
+ /* reject if this is not an unset and we don't allow that */
+ if (is_audit_feature_set(AUDIT_FEATURE_ONLY_UNSET_LOGINUID) && uid_valid(loginuid))
+ return -EPERM;
+ return 0;
+}
+
+static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid,
+ unsigned int oldsessionid, unsigned int sessionid,
+ int rc)
+{
+ struct audit_buffer *ab;
+ uid_t uid, ologinuid, nloginuid;
+
+ uid = from_kuid(&init_user_ns, task_uid(current));
+ ologinuid = from_kuid(&init_user_ns, koldloginuid);
+ nloginuid = from_kuid(&init_user_ns, kloginuid),
+
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
+ if (!ab)
+ return;
+ audit_log_format(ab, "pid=%d uid=%u old auid=%u new auid=%u old "
+ "ses=%u new ses=%u res=%d", current->pid, uid, ologinuid,
+ nloginuid, oldsessionid, sessionid, !rc);
+ audit_log_end(ab);
+}
+
/**
* audit_set_loginuid - set current task's audit_context loginuid
* @loginuid: loginuid value
@@ -1975,37 +1995,26 @@ static atomic_t session_id = ATOMIC_INIT(0);
int audit_set_loginuid(kuid_t loginuid)
{
struct task_struct *task = current;
- struct audit_context *context = task->audit_context;
- unsigned int sessionid;
+ unsigned int oldsessionid, sessionid = (unsigned int)-1;
+ kuid_t oldloginuid;
+ int rc;
-#ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE
- if (audit_loginuid_set(task))
- return -EPERM;
-#else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
- if (!capable(CAP_AUDIT_CONTROL))
- return -EPERM;
-#endif /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
+ oldloginuid = audit_get_loginuid(current);
+ oldsessionid = audit_get_sessionid(current);
- sessionid = atomic_inc_return(&session_id);
- if (context && context->in_syscall) {
- struct audit_buffer *ab;
+ rc = audit_set_loginuid_perm(loginuid);
+ if (rc)
+ goto out;
+
+ /* are we setting or clearing? */
+ if (uid_valid(loginuid))
+ sessionid = atomic_inc_return(&session_id);
- ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
- if (ab) {
- audit_log_format(ab, "login pid=%d uid=%u "
- "old auid=%u new auid=%u"
- " old ses=%u new ses=%u",
- task->pid,
- from_kuid(&init_user_ns, task_uid(task)),
- from_kuid(&init_user_ns, task->loginuid),
- from_kuid(&init_user_ns, loginuid),
- task->sessionid, sessionid);
- audit_log_end(ab);
- }
- }
task->sessionid = sessionid;
task->loginuid = loginuid;
- return 0;
+out:
+ audit_log_set_loginuid(oldloginuid, loginuid, oldsessionid, sessionid, rc);
+ return rc;
}
/**
@@ -2126,22 +2135,12 @@ void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mo
context->ipc.has_perm = 1;
}
-int __audit_bprm(struct linux_binprm *bprm)
+void __audit_bprm(struct linux_binprm *bprm)
{
- struct audit_aux_data_execve *ax;
struct audit_context *context = current->audit_context;
- ax = kmalloc(sizeof(*ax), GFP_KERNEL);
- if (!ax)
- return -ENOMEM;
-
- ax->argc = bprm->argc;
- ax->envc = bprm->envc;
- ax->mm = bprm->mm;
- ax->d.type = AUDIT_EXECVE;
- ax->d.next = context->aux;
- context->aux = (void *)ax;
- return 0;
+ context->type = AUDIT_EXECVE;
+ context->execve.argc = bprm->argc;
}