audit: Use current instead of NETLINK_CREDS() in audit_filter

Get caller process uid and gid and pid values from the current task
instead of the NETLINK_CB.  This is simpler than passing NETLINK_CREDS
from from audit_receive_msg to audit_filter_user_rules and avoid the
chance of being hit by the occassional bugs in netlink uid/gid
credential passing.  This is a safe changes because all netlink
requests are processed in the task of the sending process.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman 2012-09-10 23:10:16 -07:00
parent 34e36d8ecb
commit 02276bda4a
3 changed files with 8 additions and 9 deletions

View file

@ -700,7 +700,7 @@ extern void audit_log_secctx(struct audit_buffer *ab, u32 secid);
extern int audit_update_lsm_rules(void);
/* Private API (for audit.c only) */
extern int audit_filter_user(struct netlink_skb_parms *cb);
extern int audit_filter_user(void);
extern int audit_filter_type(int type);
extern int audit_receive_filter(int type, int pid, int uid, int seq,
void *data, size_t datasz, uid_t loginuid,

View file

@ -744,7 +744,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
if (!audit_enabled && msg_type != AUDIT_USER_AVC)
return 0;
err = audit_filter_user(&NETLINK_CB(skb));
err = audit_filter_user();
if (err == 1) {
err = 0;
if (msg_type == AUDIT_USER_TTY) {

View file

@ -1236,8 +1236,7 @@ int audit_compare_dname_path(const char *dname, const char *path,
return strncmp(p, dname, dlen);
}
static int audit_filter_user_rules(struct netlink_skb_parms *cb,
struct audit_krule *rule,
static int audit_filter_user_rules(struct audit_krule *rule,
enum audit_state *state)
{
int i;
@ -1249,13 +1248,13 @@ static int audit_filter_user_rules(struct netlink_skb_parms *cb,
switch (f->type) {
case AUDIT_PID:
result = audit_comparator(cb->creds.pid, f->op, f->val);
result = audit_comparator(task_pid_vnr(current), f->op, f->val);
break;
case AUDIT_UID:
result = audit_comparator(cb->creds.uid, f->op, f->val);
result = audit_comparator(current_uid(), f->op, f->val);
break;
case AUDIT_GID:
result = audit_comparator(cb->creds.gid, f->op, f->val);
result = audit_comparator(current_gid(), f->op, f->val);
break;
case AUDIT_LOGINUID:
result = audit_comparator(audit_get_loginuid(current),
@ -1287,7 +1286,7 @@ static int audit_filter_user_rules(struct netlink_skb_parms *cb,
return 1;
}
int audit_filter_user(struct netlink_skb_parms *cb)
int audit_filter_user(void)
{
enum audit_state state = AUDIT_DISABLED;
struct audit_entry *e;
@ -1295,7 +1294,7 @@ int audit_filter_user(struct netlink_skb_parms *cb)
rcu_read_lock();
list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) {
if (audit_filter_user_rules(cb, &e->rule, &state)) {
if (audit_filter_user_rules(&e->rule, &state)) {
if (state == AUDIT_DISABLED)
ret = 0;
break;