Merge branch 'mpi-master' into wip-k-fmlpwip-k-fmlp

Conflicts:
	litmus/sched_cedf.c

1 files changed, 360 insertions, 0 deletions

diff --git a/drivers/tty/tty_audit.c b/drivers/tty/tty_audit.c
new file mode 100644
index 000000000000..7c5866920622
--- /dev/null
+++ b/drivers/tty/tty_audit.c
@@ -0,0 +1,360 @@
+/*
+ * Creating audit events from TTY input.
+ *
+ * Copyright (C) 2007 Red Hat, Inc.  All rights reserved.  This copyrighted
+ * material is made available to anyone wishing to use, modify, copy, or
+ * redistribute it subject to the terms and conditions of the GNU General
+ * Public License v.2.
+ *
+ * Authors: Miloslav Trmac <mitr@redhat.com>
+ */
+
+#include <linux/audit.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+
+struct tty_audit_buf {
+        atomic_t count;
+        struct mutex mutex;     /* Protects all data below */
+        int major, minor;       /* The TTY which the data is from */
+        unsigned icanon:1;
+        size_t valid;
+        unsigned char *data;    /* Allocated size N_TTY_BUF_SIZE */
+};
+
+static struct tty_audit_buf *tty_audit_buf_alloc(int major, int minor,
+                                                 int icanon)
+{
+        struct tty_audit_buf *buf;
+
+        buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+        if (!buf)
+                goto err;
+        buf->data = kmalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
+        if (!buf->data)
+                goto err_buf;
+        atomic_set(&buf->count, 1);
+        mutex_init(&buf->mutex);
+        buf->major = major;
+        buf->minor = minor;
+        buf->icanon = icanon;
+        buf->valid = 0;
+        return buf;
+
+err_buf:
+        kfree(buf);
+err:
+        return NULL;
+}
+
+static void tty_audit_buf_free(struct tty_audit_buf *buf)
+{
+        WARN_ON(buf->valid != 0);
+        kfree(buf->data);
+        kfree(buf);
+}
+
+static void tty_audit_buf_put(struct tty_audit_buf *buf)
+{
+        if (atomic_dec_and_test(&buf->count))
+                tty_audit_buf_free(buf);
+}
+
+static void tty_audit_log(const char *description, struct task_struct *tsk,
+                          uid_t loginuid, unsigned sessionid, int major,
+                          int minor, unsigned char *data, size_t size)
+{
+        struct audit_buffer *ab;
+
+        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_TTY);
+        if (ab) {
+                char name[sizeof(tsk->comm)];
+                uid_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, loginuid, sessionid,
+                                 major, minor);
+                get_task_comm(name, tsk);
+                audit_log_untrustedstring(ab, name);
+                audit_log_format(ab, " data=");
+                audit_log_n_hex(ab, data, size);
+                audit_log_end(ab);
+        }
+}
+
+/**
+ *      tty_audit_buf_push      -       Push buffered data out
+ *
+ *      Generate an audit message from the contents of @buf, which is owned by
+ *      @tsk with @loginuid.  @buf->mutex must be locked.
+ */
+static void tty_audit_buf_push(struct task_struct *tsk, uid_t loginuid,
+                               unsigned int sessionid,
+                               struct tty_audit_buf *buf)
+{
+        if (buf->valid == 0)
+                return;
+        if (audit_enabled == 0) {
+                buf->valid = 0;
+                return;
+        }
+        tty_audit_log("tty", tsk, loginuid, sessionid, buf->major, buf->minor,
+                      buf->data, buf->valid);
+        buf->valid = 0;
+}
+
+/**
+ *      tty_audit_buf_push_current      -       Push buffered data out
+ *
+ *      Generate an audit message from the contents of @buf, which is owned by
+ *      the current task.  @buf->mutex must be locked.
+ */
+static void tty_audit_buf_push_current(struct tty_audit_buf *buf)
+{
+        uid_t auid = audit_get_loginuid(current);
+        unsigned int sessionid = audit_get_sessionid(current);
+        tty_audit_buf_push(current, auid, sessionid, buf);
+}
+
+/**
+ *      tty_audit_exit  -       Handle a task exit
+ *
+ *      Make sure all buffered data is written out and deallocate the buffer.
+ *      Only needs to be called if current->signal->tty_audit_buf != %NULL.
+ */
+void tty_audit_exit(void)
+{
+        struct tty_audit_buf *buf;
+
+        spin_lock_irq(&current->sighand->siglock);
+        buf = current->signal->tty_audit_buf;
+        current->signal->tty_audit_buf = NULL;
+        spin_unlock_irq(&current->sighand->siglock);
+        if (!buf)
+                return;
+
+        mutex_lock(&buf->mutex);
+        tty_audit_buf_push_current(buf);
+        mutex_unlock(&buf->mutex);
+
+        tty_audit_buf_put(buf);
+}
+
+/**
+ *      tty_audit_fork  -       Copy TTY audit state for a new task
+ *
+ *      Set up TTY audit state in @sig from current.  @sig needs no locking.
+ */
+void tty_audit_fork(struct signal_struct *sig)
+{
+        spin_lock_irq(&current->sighand->siglock);
+        sig->audit_tty = current->signal->audit_tty;
+        spin_unlock_irq(&current->sighand->siglock);
+}
+
+/**
+ *      tty_audit_tiocsti       -       Log TIOCSTI
+ */
+void tty_audit_tiocsti(struct tty_struct *tty, char ch)
+{
+        struct tty_audit_buf *buf;
+        int major, minor, should_audit;
+
+        spin_lock_irq(&current->sighand->siglock);
+        should_audit = current->signal->audit_tty;
+        buf = current->signal->tty_audit_buf;
+        if (buf)
+                atomic_inc(&buf->count);
+        spin_unlock_irq(&current->sighand->siglock);
+
+        major = tty->driver->major;
+        minor = tty->driver->minor_start + tty->index;
+        if (buf) {
+                mutex_lock(&buf->mutex);
+                if (buf->major == major && buf->minor == minor)
+                        tty_audit_buf_push_current(buf);
+                mutex_unlock(&buf->mutex);
+                tty_audit_buf_put(buf);
+        }
+
+        if (should_audit && audit_enabled) {
+                uid_t auid;
+                unsigned int sessionid;
+
+                auid = audit_get_loginuid(current);
+                sessionid = audit_get_sessionid(current);
+                tty_audit_log("ioctl=TIOCSTI", current, auid, sessionid, major,
+                              minor, &ch, 1);
+        }
+}
+
+/**
+ * tty_audit_push_task  -       Flush task's pending audit data
+ * @tsk:                task pointer
+ * @loginuid:           sender login uid
+ * @sessionid:          sender session id
+ *
+ * Called with a ref on @tsk held. Try to lock sighand and get a
+ * reference to the tty audit buffer if available.
+ * Flush the buffer or return an appropriate error code.
+ */
+int tty_audit_push_task(struct task_struct *tsk, uid_t loginuid, u32 sessionid)
+{
+        struct tty_audit_buf *buf = ERR_PTR(-EPERM);
+        unsigned long flags;
+
+        if (!lock_task_sighand(tsk, &flags))
+                return -ESRCH;
+
+        if (tsk->signal->audit_tty) {
+                buf = tsk->signal->tty_audit_buf;
+                if (buf)
+                        atomic_inc(&buf->count);
+        }
+        unlock_task_sighand(tsk, &flags);
+
+        /*
+         * Return 0 when signal->audit_tty set
+         * but tsk->signal->tty_audit_buf == NULL.
+         */
+        if (!buf || IS_ERR(buf))
+                return PTR_ERR(buf);
+
+        mutex_lock(&buf->mutex);
+        tty_audit_buf_push(tsk, loginuid, sessionid, buf);
+        mutex_unlock(&buf->mutex);
+
+        tty_audit_buf_put(buf);
+        return 0;
+}
+
+/**
+ *      tty_audit_buf_get       -       Get an audit buffer.
+ *
+ *      Get an audit buffer for @tty, allocate it if necessary.  Return %NULL
+ *      if TTY auditing is disabled or out of memory.  Otherwise, return a new
+ *      reference to the buffer.
+ */
+static struct tty_audit_buf *tty_audit_buf_get(struct tty_struct *tty)
+{
+        struct tty_audit_buf *buf, *buf2;
+
+        buf = NULL;
+        buf2 = NULL;
+        spin_lock_irq(&current->sighand->siglock);
+        if (likely(!current->signal->audit_tty))
+                goto out;
+        buf = current->signal->tty_audit_buf;
+        if (buf) {
+                atomic_inc(&buf->count);
+                goto out;
+        }
+        spin_unlock_irq(&current->sighand->siglock);
+
+        buf2 = tty_audit_buf_alloc(tty->driver->major,
+                                   tty->driver->minor_start + tty->index,
+                                   tty->icanon);
+        if (buf2 == NULL) {
+                audit_log_lost("out of memory in TTY auditing");
+                return NULL;
+        }
+
+        spin_lock_irq(&current->sighand->siglock);
+        if (!current->signal->audit_tty)
+                goto out;
+        buf = current->signal->tty_audit_buf;
+        if (!buf) {
+                current->signal->tty_audit_buf = buf2;
+                buf = buf2;
+                buf2 = NULL;
+        }
+        atomic_inc(&buf->count);
+        /* Fall through */
+ out:
+        spin_unlock_irq(&current->sighand->siglock);
+        if (buf2)
+                tty_audit_buf_free(buf2);
+        return buf;
+}
+
+/**
+ *      tty_audit_add_data      -       Add data for TTY auditing.
+ *
+ *      Audit @data of @size from @tty, if necessary.
+ */
+void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
+                        size_t size)
+{
+        struct tty_audit_buf *buf;
+        int major, minor;
+
+        if (unlikely(size == 0))
+                return;
+
+        if (tty->driver->type == TTY_DRIVER_TYPE_PTY
+            && tty->driver->subtype == PTY_TYPE_MASTER)
+                return;
+
+        buf = tty_audit_buf_get(tty);
+        if (!buf)
+                return;
+
+        mutex_lock(&buf->mutex);
+        major = tty->driver->major;
+        minor = tty->driver->minor_start + tty->index;
+        if (buf->major != major || buf->minor != minor
+            || buf->icanon != tty->icanon) {
+                tty_audit_buf_push_current(buf);
+                buf->major = major;
+                buf->minor = minor;
+                buf->icanon = tty->icanon;
+        }
+        do {
+                size_t run;
+
+                run = N_TTY_BUF_SIZE - buf->valid;
+                if (run > size)
+                        run = size;
+                memcpy(buf->data + buf->valid, data, run);
+                buf->valid += run;
+                data += run;
+                size -= run;
+                if (buf->valid == N_TTY_BUF_SIZE)
+                        tty_audit_buf_push_current(buf);
+        } while (size != 0);
+        mutex_unlock(&buf->mutex);
+        tty_audit_buf_put(buf);
+}
+
+/**
+ *      tty_audit_push  -       Push buffered data out
+ *
+ *      Make sure no audit data is pending for @tty on the current process.
+ */
+void tty_audit_push(struct tty_struct *tty)
+{
+        struct tty_audit_buf *buf;
+
+        spin_lock_irq(&current->sighand->siglock);
+        if (likely(!current->signal->audit_tty)) {
+                spin_unlock_irq(&current->sighand->siglock);
+                return;
+        }
+        buf = current->signal->tty_audit_buf;
+        if (buf)
+                atomic_inc(&buf->count);
+        spin_unlock_irq(&current->sighand->siglock);
+
+        if (buf) {
+                int major, minor;
+
+                major = tty->driver->major;
+                minor = tty->driver->minor_start + tty->index;
+                mutex_lock(&buf->mutex);
+                if (buf->major == major && buf->minor == minor)
+                        tty_audit_buf_push_current(buf);
+                mutex_unlock(&buf->mutex);
+                tty_audit_buf_put(buf);
+        }
+}