userns: Convert audit to work with user namespaces enabled

- Explicitly format uids gids in audit messges in the initial user
  namespace. This is safe because auditd is restrected to be in
  the initial user namespace.

- Convert audit_sig_uid into a kuid_t.

- Enable building the audit code and user namespaces at the same time.

The net result is that the audit subsystem now uses kuid_t and kgid_t whenever
possible making it almost impossible to confuse a raw uid_t with a kuid_t
preventing bugs.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

diff --git a/drivers/tty/tty_audit.c b/drivers/tty/tty_audit.c
index 5b59bd7f422720e0d415888505920af7f851a2a9..b0b39b823ccf16ec2e0b82264721a0be7e54005f 100644 (file)
--- a/drivers/tty/tty_audit.c
+++ b/drivers/tty/tty_audit.c
@@ -69,11 +69,12 @@ static void tty_audit_log(const char *description, struct task_struct *tsk,
        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_TTY);
        if (ab) {
                char name[sizeof(tsk->comm)];
-               uid_t uid = task_uid(tsk);
+               kuid_t uid = task_uid(tsk);
 
                audit_log_format(ab, "%s pid=%u uid=%u auid=%u ses=%u "
                                 "major=%d minor=%d comm=", description,
-                                tsk->pid, uid,
+                                tsk->pid,
+                                from_kuid(&init_user_ns, uid),
                                 from_kuid(&init_user_ns, loginuid),
                                 sessionid,
                                 major, minor);

diff --git a/init/Kconfig b/init/Kconfig
index fd8696b1a81e3299e6aa0308315369a2f7a4fd47..b5ecb4e7551862232ae2e90ddb16e437b2b99b4c 100644 (file)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -927,8 +927,6 @@ config UIDGID_CONVERTED
        # Features
        depends on IMA = n
        depends on EVM = n
-       depends on AUDIT = n
-       depends on AUDITSYSCALL = n
        depends on TASKSTATS = n
        depends on TRACING = n
        depends on FS_POSIX_ACL = n

diff --git a/kernel/audit.c b/kernel/audit.c
index 44a4b13c9f0067550ecb256e010152c8faa9fabb..511488a7bc71d0f1f6265ed9c3fe62838923a18b 100644 (file)
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -105,7 +105,7 @@ static int  audit_backlog_wait_time = 60 * HZ;
 static int     audit_backlog_wait_overflow = 0;
 
 /* The identity of the user shutting down the audit system. */
-uid_t          audit_sig_uid = -1;
+kuid_t         audit_sig_uid = INVALID_UID;
 pid_t          audit_sig_pid = -1;
 u32            audit_sig_sid = 0;
 
@@ -853,7 +853,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                                security_release_secctx(ctx, len);
                        return -ENOMEM;
                }
-               sig_data->uid = audit_sig_uid;
+               sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
                sig_data->pid = audit_sig_pid;
                if (audit_sig_sid) {
                        memcpy(sig_data->ctx, ctx, len);

diff --git a/kernel/audit.h b/kernel/audit.h
index 4b428bb41ea31f5e4fd141b1d108d341f751e3fb..9eb3d79482b64ca398ed38ae4b9ab861048a17a1 100644 (file)
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -146,7 +146,7 @@ extern void audit_kill_trees(struct list_head *);
 extern char *audit_unpack_string(void **, size_t *, size_t);
 
 extern pid_t audit_sig_pid;
-extern uid_t audit_sig_uid;
+extern kuid_t audit_sig_uid;
 extern u32 audit_sig_sid;
 
 #ifdef CONFIG_AUDITSYSCALL

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 26fdfc092e356513d3ea7f400daa62921fe647a6..ff4798fcb4884d371f5b393c11dbcd8c585e1fbb 100644 (file)
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -150,7 +150,7 @@ struct audit_aux_data_pids {
        struct audit_aux_data   d;
        pid_t                   target_pid[AUDIT_AUX_PIDS];
        kuid_t                  target_auid[AUDIT_AUX_PIDS];
-       uid_t                   target_uid[AUDIT_AUX_PIDS];
+       kuid_t                  target_uid[AUDIT_AUX_PIDS];
        unsigned int            target_sessionid[AUDIT_AUX_PIDS];
        u32                     target_sid[AUDIT_AUX_PIDS];
        char                    target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
@@ -208,14 +208,14 @@ struct audit_context {
        size_t sockaddr_len;
                                /* Save things to print about task_struct */
        pid_t               pid, ppid;
-       uid_t               uid, euid, suid, fsuid;
-       gid_t               gid, egid, sgid, fsgid;
+       kuid_t              uid, euid, suid, fsuid;
+       kgid_t              gid, egid, sgid, fsgid;
        unsigned long       personality;
        int                 arch;
 
        pid_t               target_pid;
        kuid_t              target_auid;
-       uid_t               target_uid;
+       kuid_t              target_uid;
        unsigned int        target_sessionid;
        u32                 target_sid;
        char                target_comm[TASK_COMM_LEN];
@@ -231,8 +231,8 @@ struct audit_context {
                        long args[6];
                } socketcall;
                struct {
-                       uid_t                   uid;
-                       gid_t                   gid;
+                       kuid_t                  uid;
+                       kgid_t                  gid;
                        umode_t                 mode;
                        u32                     osid;
                        int                     has_perm;
@@ -1176,7 +1176,7 @@ static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk
 }
 
 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
-                                kuid_t auid, uid_t uid, unsigned int sessionid,
+                                kuid_t auid, kuid_t uid, unsigned int sessionid,
                                 u32 sid, char *comm)
 {
        struct audit_buffer *ab;
@@ -1190,7 +1190,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 
        audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
                         from_kuid(&init_user_ns, auid),
-                        uid, sessionid);
+                        from_kuid(&init_user_ns, uid), sessionid);
        if (security_secid_to_secctx(sid, &ctx, &len)) {
                audit_log_format(ab, " obj=(none)");
                rc = 1;
@@ -1440,7 +1440,9 @@ static void show_special(struct audit_context *context, int *call_panic)
                u32 osid = context->ipc.osid;
 
                audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
-                        context->ipc.uid, context->ipc.gid, context->ipc.mode);
+                                from_kuid(&init_user_ns, context->ipc.uid),
+                                from_kgid(&init_user_ns, context->ipc.gid),
+                                context->ipc.mode);
                if (osid) {
                        char *ctx = NULL;
                        u32 len;
@@ -1553,8 +1555,8 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
                                 MAJOR(n->dev),
                                 MINOR(n->dev),
                                 n->mode,
-                                n->uid,
-                                n->gid,
+                                from_kuid(&init_user_ns, n->uid),
+                                from_kgid(&init_user_ns, n->gid),
                                 MAJOR(n->rdev),
                                 MINOR(n->rdev));
        }
@@ -1632,10 +1634,15 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
                  context->ppid,
                  context->pid,
                  from_kuid(&init_user_ns, tsk->loginuid),
-                 context->uid,
-                 context->gid,
-                 context->euid, context->suid, context->fsuid,
-                 context->egid, context->sgid, context->fsgid, tty,
+                 from_kuid(&init_user_ns, context->uid),
+                 from_kgid(&init_user_ns, context->gid),
+                 from_kuid(&init_user_ns, context->euid),
+                 from_kuid(&init_user_ns, context->suid),
+                 from_kuid(&init_user_ns, context->fsuid),
+                 from_kgid(&init_user_ns, context->egid),
+                 from_kgid(&init_user_ns, context->sgid),
+                 from_kgid(&init_user_ns, context->fsgid),
+                 tty,
                  tsk->sessionid);
 
 
@@ -2315,7 +2322,8 @@ int audit_set_loginuid(kuid_t loginuid)
                        audit_log_format(ab, "login pid=%d uid=%u "
                                "old auid=%u new auid=%u"
                                " old ses=%u new ses=%u",
-                               task->pid, task_uid(task),
+                               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);
@@ -2540,7 +2548,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
        struct audit_aux_data_pids *axp;
        struct task_struct *tsk = current;
        struct audit_context *ctx = tsk->audit_context;
-       uid_t uid = current_uid(), t_uid = task_uid(t);
+       kuid_t uid = current_uid(), t_uid = task_uid(t);
 
        if (audit_pid && t->tgid == audit_pid) {
                if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
@@ -2666,8 +2674,8 @@ void __audit_mmap_fd(int fd, int flags)
 
 static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
 {
-       uid_t auid, uid;
-       gid_t gid;
+       kuid_t auid, uid;
+       kgid_t gid;
        unsigned int sessionid;
 
        auid = audit_get_loginuid(current);
@@ -2675,7 +2683,10 @@ static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
        current_uid_gid(&uid, &gid);
 
        audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
-                        auid, uid, gid, sessionid);
+                        from_kuid(&init_user_ns, auid),
+                        from_kuid(&init_user_ns, uid),
+                        from_kgid(&init_user_ns, gid),
+                        sessionid);
        audit_log_task_context(ab);
        audit_log_format(ab, " pid=%d comm=", current->pid);
        audit_log_untrustedstring(ab, current->comm);