Merge git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-nommu

[linux-2.6-omap-h63xx.git] / kernel / fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index 495da2e9a8b4d92a1b464b98196228f818c892e7..1d68f1255dd824cf2fd1c06a1e6464bac718d26f 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -47,6 +47,7 @@
 #include <linux/mount.h>
 #include <linux/audit.h>
 #include <linux/memcontrol.h>
+#include <linux/ftrace.h>
 #include <linux/profile.h>
 #include <linux/rmap.h>
 #include <linux/acct.h>
@@ -80,6 +81,8 @@ DEFINE_PER_CPU(unsigned long, process_counts) = 0;
 
 __cacheline_aligned DEFINE_RWLOCK(tasklist_lock);  /* outer */
 
+DEFINE_TRACE(sched_process_fork);
+
 int nr_processes(void)
 {
        int cpu;
@@ -137,6 +140,7 @@ void free_task(struct task_struct *tsk)
        prop_local_destroy_single(&tsk->dirties);
        free_thread_info(tsk->stack);
        rt_mutex_debug_task_free(tsk);
+       ftrace_graph_exit_task(tsk);
        free_task_struct(tsk);
 }
 EXPORT_SYMBOL(free_task);
@@ -147,9 +151,8 @@ void __put_task_struct(struct task_struct *tsk)
        WARN_ON(atomic_read(&tsk->usage));
        WARN_ON(tsk == current);
 
-       security_task_free(tsk);
-       free_uid(tsk->user);
-       put_group_info(tsk->group_info);
+       put_cred(tsk->real_cred);
+       put_cred(tsk->cred);
        delayacct_tsk_free(tsk);
 
        if (!profile_handoff_task(tsk))
@@ -397,6 +400,18 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock);
 #define allocate_mm()  (kmem_cache_alloc(mm_cachep, GFP_KERNEL))
 #define free_mm(mm)    (kmem_cache_free(mm_cachep, (mm)))
 
+static unsigned long default_dump_filter = MMF_DUMP_FILTER_DEFAULT;
+
+static int __init coredump_filter_setup(char *s)
+{
+       default_dump_filter =
+               (simple_strtoul(s, NULL, 0) << MMF_DUMP_FILTER_SHIFT) &
+               MMF_DUMP_FILTER_MASK;
+       return 1;
+}
+
+__setup("coredump_filter=", coredump_filter_setup);
+
 #include <linux/init_task.h>
 
 static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p)
@@ -405,15 +420,14 @@ static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p)
        atomic_set(&mm->mm_count, 1);
        init_rwsem(&mm->mmap_sem);
        INIT_LIST_HEAD(&mm->mmlist);
-       mm->flags = (current->mm) ? current->mm->flags
-                                 : MMF_DUMP_FILTER_DEFAULT;
+       mm->flags = (current->mm) ? current->mm->flags : default_dump_filter;
        mm->core_state = NULL;
        mm->nr_ptes = 0;
        set_mm_counter(mm, file_rss, 0);
        set_mm_counter(mm, anon_rss, 0);
        spin_lock_init(&mm->page_table_lock);
-       rwlock_init(&mm->ioctx_list_lock);
-       mm->ioctx_list = NULL;
+       spin_lock_init(&mm->ioctx_lock);
+       INIT_HLIST_HEAD(&mm->ioctx_list);
        mm->free_area_cache = TASK_UNMAPPED_BASE;
        mm->cached_hole_size = ~0UL;
        mm_init_owner(mm, p);
@@ -755,7 +769,7 @@ static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk)
 {
        struct sighand_struct *sig;
 
-       if (clone_flags & (CLONE_SIGHAND | CLONE_THREAD)) {
+       if (clone_flags & CLONE_SIGHAND) {
                atomic_inc(&current->sighand->count);
                return 0;
        }
@@ -818,12 +832,6 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
        if (!sig)
                return -ENOMEM;
 
-       ret = copy_thread_group_keys(tsk);
-       if (ret < 0) {
-               kmem_cache_free(signal_cachep, sig);
-               return ret;
-       }
-
        atomic_set(&sig->count, 1);
        atomic_set(&sig->live, 1);
        init_waitqueue_head(&sig->wait_chldexit);
@@ -868,7 +876,6 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
 void __cleanup_signal(struct signal_struct *sig)
 {
        thread_group_cputime_free(sig);
-       exit_thread_group_keys(sig);
        tty_kref_put(sig->tty);
        kmem_cache_free(signal_cachep, sig);
 }
@@ -984,16 +991,16 @@ static struct task_struct *copy_process(unsigned long clone_flags,
        DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
 #endif
        retval = -EAGAIN;
-       if (atomic_read(&p->user->processes) >=
+       if (atomic_read(&p->real_cred->user->processes) >=
                        p->signal->rlim[RLIMIT_NPROC].rlim_cur) {
                if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE) &&
-                   p->user != current->nsproxy->user_ns->root_user)
+                   p->real_cred->user != INIT_USER)
                        goto bad_fork_free;
        }
 
-       atomic_inc(&p->user->__count);
-       atomic_inc(&p->user->processes);
-       get_group_info(p->group_info);
+       retval = copy_creds(p, clone_flags);
+       if (retval < 0)
+               goto bad_fork_free;
 
        /*
         * If multiple threads are within copy_process(), then this check
@@ -1048,10 +1055,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
        do_posix_clock_monotonic_gettime(&p->start_time);
        p->real_start_time = p->start_time;
        monotonic_to_bootbased(&p->real_start_time);
-#ifdef CONFIG_SECURITY
-       p->security = NULL;
-#endif
-       p->cap_bset = current->cap_bset;
        p->io_context = NULL;
        p->audit_context = NULL;
        cgroup_fork(p);
@@ -1092,14 +1095,14 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 #ifdef CONFIG_DEBUG_MUTEXES
        p->blocked_on = NULL; /* not blocked yet */
 #endif
+       if (unlikely(ptrace_reparented(current)))
+               ptrace_fork(p, clone_flags);
 
        /* Perform scheduler related setup. Assign this task to a CPU. */
        sched_fork(p, clone_flags);
 
-       if ((retval = security_task_alloc(p)))
-               goto bad_fork_cleanup_policy;
        if ((retval = audit_alloc(p)))
-               goto bad_fork_cleanup_security;
+               goto bad_fork_cleanup_policy;
        /* copy all the process information */
        if ((retval = copy_semundo(clone_flags, p)))
                goto bad_fork_cleanup_audit;
@@ -1113,10 +1116,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                goto bad_fork_cleanup_sighand;
        if ((retval = copy_mm(clone_flags, p)))
                goto bad_fork_cleanup_signal;
-       if ((retval = copy_keys(clone_flags, p)))
-               goto bad_fork_cleanup_mm;
        if ((retval = copy_namespaces(clone_flags, p)))
-               goto bad_fork_cleanup_keys;
+               goto bad_fork_cleanup_mm;
        if ((retval = copy_io(clone_flags, p)))
                goto bad_fork_cleanup_namespaces;
        retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs);
@@ -1125,17 +1126,19 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 
        if (pid != &init_struct_pid) {
                retval = -ENOMEM;
-               pid = alloc_pid(task_active_pid_ns(p));
+               pid = alloc_pid(p->nsproxy->pid_ns);
                if (!pid)
                        goto bad_fork_cleanup_io;
 
                if (clone_flags & CLONE_NEWPID) {
-                       retval = pid_ns_prepare_proc(task_active_pid_ns(p));
+                       retval = pid_ns_prepare_proc(p->nsproxy->pid_ns);
                        if (retval < 0)
                                goto bad_fork_free_pid;
                }
        }
 
+       ftrace_graph_init_task(p);
+
        p->pid = pid_nr(pid);
        p->tgid = p->pid;
        if (clone_flags & CLONE_THREAD)
@@ -1144,7 +1147,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
        if (current->nsproxy != p->nsproxy) {
                retval = ns_cgroup_clone(p, pid);
                if (retval)
-                       goto bad_fork_free_pid;
+                       goto bad_fork_free_graph;
        }
 
        p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
@@ -1237,7 +1240,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                spin_unlock(&current->sighand->siglock);
                write_unlock_irq(&tasklist_lock);
                retval = -ERESTARTNOINTR;
-               goto bad_fork_free_pid;
+               goto bad_fork_free_graph;
        }
 
        if (clone_flags & CLONE_THREAD) {
@@ -1274,6 +1277,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
        cgroup_post_fork(p);
        return p;
 
+bad_fork_free_graph:
+       ftrace_graph_exit_task(p);
 bad_fork_free_pid:
        if (pid != &init_struct_pid)
                free_pid(pid);
@@ -1281,8 +1286,6 @@ bad_fork_cleanup_io:
        put_io_context(p->io_context);
 bad_fork_cleanup_namespaces:
        exit_task_namespaces(p);
-bad_fork_cleanup_keys:
-       exit_keys(p);
 bad_fork_cleanup_mm:
        if (p->mm)
                mmput(p->mm);
@@ -1298,8 +1301,6 @@ bad_fork_cleanup_semundo:
        exit_sem(p);
 bad_fork_cleanup_audit:
        audit_free(p);
-bad_fork_cleanup_security:
-       security_task_free(p);
 bad_fork_cleanup_policy:
 #ifdef CONFIG_NUMA
        mpol_put(p->mempolicy);
@@ -1312,9 +1313,9 @@ bad_fork_cleanup_cgroup:
 bad_fork_cleanup_put_domain:
        module_put(task_thread_info(p)->exec_domain->module);
 bad_fork_cleanup_count:
-       put_group_info(p->group_info);
-       atomic_dec(&p->user->processes);
-       free_uid(p->user);
+       atomic_dec(&p->cred->user->processes);
+       put_cred(p->real_cred);
+       put_cred(p->cred);
 bad_fork_free:
        free_task(p);
 fork_out:
@@ -1357,6 +1358,21 @@ long do_fork(unsigned long clone_flags,
        int trace = 0;
        long nr;
 
+       /*
+        * Do some preliminary argument and permissions checking before we
+        * actually start allocating stuff
+        */
+       if (clone_flags & CLONE_NEWUSER) {
+               if (clone_flags & CLONE_THREAD)
+                       return -EINVAL;
+               /* hopefully this check will go away when userns support is
+                * complete
+                */
+               if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SETUID) ||
+                               !capable(CAP_SETGID))
+                       return -EPERM;
+       }
+
        /*
         * We hope to recycle these flags after 2.6.26
         */
@@ -1465,12 +1481,10 @@ void __init proc_caches_init(void)
        fs_cachep = kmem_cache_create("fs_cache",
                        sizeof(struct fs_struct), 0,
                        SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
-       vm_area_cachep = kmem_cache_create("vm_area_struct",
-                       sizeof(struct vm_area_struct), 0,
-                       SLAB_PANIC, NULL);
        mm_cachep = kmem_cache_create("mm_struct",
                        sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN,
                        SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+       mmap_init();
 }
 
 /*
@@ -1605,8 +1619,7 @@ asmlinkage long sys_unshare(unsigned long unshare_flags)
        err = -EINVAL;
        if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND|
                                CLONE_VM|CLONE_FILES|CLONE_SYSVSEM|
-                               CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWUSER|
-                               CLONE_NEWNET))
+                               CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET))
                goto bad_unshare_out;
 
        /*