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authorIngo Molnar <mingo@elte.hu>2008-12-31 08:31:57 +0100
committerIngo Molnar <mingo@elte.hu>2008-12-31 08:31:57 +0100
commita9de18eb761f7c1c860964b2e5addc1a35c7e861 (patch)
tree886e75fdfd09690cd262ca69cb7f5d1d42b48602 /kernel/fork.c
parentb2aaf8f74cdc84a9182f6cabf198b7763bcb9d40 (diff)
parent6a94cb73064c952255336cc57731904174b2c58f (diff)
downloadop-kernel-dev-a9de18eb761f7c1c860964b2e5addc1a35c7e861.zip
op-kernel-dev-a9de18eb761f7c1c860964b2e5addc1a35c7e861.tar.gz
Merge branch 'linus' into stackprotector
Conflicts: arch/x86/include/asm/pda.h kernel/fork.c
Diffstat (limited to 'kernel/fork.c')
-rw-r--r--kernel/fork.c204
1 files changed, 118 insertions, 86 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 99c5c65..913284e 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -40,12 +40,14 @@
#include <linux/jiffies.h>
#include <linux/tracehook.h>
#include <linux/futex.h>
+#include <linux/compat.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/rcupdate.h>
#include <linux/ptrace.h>
#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>
@@ -58,6 +60,7 @@
#include <linux/tty.h>
#include <linux/proc_fs.h>
#include <linux/blkdev.h>
+#include <trace/sched.h>
#include <linux/magic.h>
#include <asm/pgtable.h>
@@ -79,6 +82,8 @@ 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;
@@ -136,6 +141,7 @@ 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);
@@ -146,9 +152,8 @@ 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))
@@ -318,17 +323,20 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
file = tmp->vm_file;
if (file) {
struct inode *inode = file->f_path.dentry->d_inode;
+ struct address_space *mapping = file->f_mapping;
+
get_file(file);
if (tmp->vm_flags & VM_DENYWRITE)
atomic_dec(&inode->i_writecount);
-
- /* insert tmp into the share list, just after mpnt */
- spin_lock(&file->f_mapping->i_mmap_lock);
+ spin_lock(&mapping->i_mmap_lock);
+ if (tmp->vm_flags & VM_SHARED)
+ mapping->i_mmap_writable++;
tmp->vm_truncate_count = mpnt->vm_truncate_count;
- flush_dcache_mmap_lock(file->f_mapping);
+ flush_dcache_mmap_lock(mapping);
+ /* insert tmp into the share list, just after mpnt */
vma_prio_tree_add(tmp, mpnt);
- flush_dcache_mmap_unlock(file->f_mapping);
- spin_unlock(&file->f_mapping->i_mmap_lock);
+ flush_dcache_mmap_unlock(mapping);
+ spin_unlock(&mapping->i_mmap_lock);
}
/*
@@ -412,8 +420,8 @@ static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p)
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);
@@ -523,6 +531,16 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
{
struct completion *vfork_done = tsk->vfork_done;
+ /* Get rid of any futexes when releasing the mm */
+#ifdef CONFIG_FUTEX
+ if (unlikely(tsk->robust_list))
+ exit_robust_list(tsk);
+#ifdef CONFIG_COMPAT
+ if (unlikely(tsk->compat_robust_list))
+ compat_exit_robust_list(tsk);
+#endif
+#endif
+
/* Get rid of any cached register state */
deactivate_mm(tsk, mm);
@@ -764,27 +782,50 @@ void __cleanup_sighand(struct sighand_struct *sighand)
kmem_cache_free(sighand_cachep, sighand);
}
+
+/*
+ * Initialize POSIX timer handling for a thread group.
+ */
+static void posix_cpu_timers_init_group(struct signal_struct *sig)
+{
+ /* Thread group counters. */
+ thread_group_cputime_init(sig);
+
+ /* Expiration times and increments. */
+ sig->it_virt_expires = cputime_zero;
+ sig->it_virt_incr = cputime_zero;
+ sig->it_prof_expires = cputime_zero;
+ sig->it_prof_incr = cputime_zero;
+
+ /* Cached expiration times. */
+ sig->cputime_expires.prof_exp = cputime_zero;
+ sig->cputime_expires.virt_exp = cputime_zero;
+ sig->cputime_expires.sched_exp = 0;
+
+ /* The timer lists. */
+ INIT_LIST_HEAD(&sig->cpu_timers[0]);
+ INIT_LIST_HEAD(&sig->cpu_timers[1]);
+ INIT_LIST_HEAD(&sig->cpu_timers[2]);
+}
+
static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
{
struct signal_struct *sig;
int ret;
if (clone_flags & CLONE_THREAD) {
- atomic_inc(&current->signal->count);
- atomic_inc(&current->signal->live);
- return 0;
+ ret = thread_group_cputime_clone_thread(current);
+ if (likely(!ret)) {
+ atomic_inc(&current->signal->count);
+ atomic_inc(&current->signal->live);
+ }
+ return ret;
}
sig = kmem_cache_alloc(signal_cachep, GFP_KERNEL);
tsk->signal = sig;
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);
@@ -800,40 +841,25 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
sig->it_real_incr.tv64 = 0;
sig->real_timer.function = it_real_fn;
- sig->it_virt_expires = cputime_zero;
- sig->it_virt_incr = cputime_zero;
- sig->it_prof_expires = cputime_zero;
- sig->it_prof_incr = cputime_zero;
-
sig->leader = 0; /* session leadership doesn't inherit */
sig->tty_old_pgrp = NULL;
sig->tty = NULL;
- sig->utime = sig->stime = sig->cutime = sig->cstime = cputime_zero;
+ sig->cutime = sig->cstime = cputime_zero;
sig->gtime = cputime_zero;
sig->cgtime = cputime_zero;
sig->nvcsw = sig->nivcsw = sig->cnvcsw = sig->cnivcsw = 0;
sig->min_flt = sig->maj_flt = sig->cmin_flt = sig->cmaj_flt = 0;
sig->inblock = sig->oublock = sig->cinblock = sig->coublock = 0;
task_io_accounting_init(&sig->ioac);
- sig->sum_sched_runtime = 0;
- INIT_LIST_HEAD(&sig->cpu_timers[0]);
- INIT_LIST_HEAD(&sig->cpu_timers[1]);
- INIT_LIST_HEAD(&sig->cpu_timers[2]);
taskstats_tgid_init(sig);
task_lock(current->group_leader);
memcpy(sig->rlim, current->signal->rlim, sizeof sig->rlim);
task_unlock(current->group_leader);
- if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
- /*
- * New sole thread in the process gets an expiry time
- * of the whole CPU time limit.
- */
- tsk->it_prof_expires =
- secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur);
- }
+ posix_cpu_timers_init_group(sig);
+
acct_init_pacct(&sig->pacct);
tty_audit_fork(sig);
@@ -843,7 +869,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
void __cleanup_signal(struct signal_struct *sig)
{
- exit_thread_group_keys(sig);
+ thread_group_cputime_free(sig);
tty_kref_put(sig->tty);
kmem_cache_free(signal_cachep, sig);
}
@@ -893,6 +919,19 @@ void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
#endif /* CONFIG_MM_OWNER */
/*
+ * Initialize POSIX timer handling for a single task.
+ */
+static void posix_cpu_timers_init(struct task_struct *tsk)
+{
+ tsk->cputime_expires.prof_exp = cputime_zero;
+ tsk->cputime_expires.virt_exp = cputime_zero;
+ tsk->cputime_expires.sched_exp = 0;
+ INIT_LIST_HEAD(&tsk->cpu_timers[0]);
+ INIT_LIST_HEAD(&tsk->cpu_timers[1]);
+ INIT_LIST_HEAD(&tsk->cpu_timers[2]);
+}
+
+/*
* This creates a new process as a copy of the old one,
* but does not actually start it yet.
*
@@ -946,16 +985,16 @@ 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
@@ -994,6 +1033,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->prev_utime = cputime_zero;
p->prev_stime = cputime_zero;
+ p->default_timer_slack_ns = current->timer_slack_ns;
+
#ifdef CONFIG_DETECT_SOFTLOCKUP
p->last_switch_count = 0;
p->last_switch_timestamp = 0;
@@ -1002,21 +1043,12 @@ static struct task_struct *copy_process(unsigned long clone_flags,
task_io_accounting_init(&p->ioac);
acct_clear_integrals(p);
- p->it_virt_expires = cputime_zero;
- p->it_prof_expires = cputime_zero;
- p->it_sched_expires = 0;
- INIT_LIST_HEAD(&p->cpu_timers[0]);
- INIT_LIST_HEAD(&p->cpu_timers[1]);
- INIT_LIST_HEAD(&p->cpu_timers[2]);
+ posix_cpu_timers_init(p);
p->lock_depth = -1; /* -1 = no lock */
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);
@@ -1057,14 +1089,14 @@ 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;
@@ -1078,10 +1110,8 @@ 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);
@@ -1101,6 +1131,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
}
}
+ ftrace_graph_init_task(p);
+
p->pid = pid_nr(pid);
p->tgid = p->pid;
if (clone_flags & CLONE_THREAD)
@@ -1109,7 +1141,7 @@ 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;
@@ -1202,27 +1234,12 @@ 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) {
p->group_leader = current->group_leader;
list_add_tail_rcu(&p->thread_group, &p->group_leader->thread_group);
-
- if (!cputime_eq(current->signal->it_virt_expires,
- cputime_zero) ||
- !cputime_eq(current->signal->it_prof_expires,
- cputime_zero) ||
- current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY ||
- !list_empty(&current->signal->cpu_timers[0]) ||
- !list_empty(&current->signal->cpu_timers[1]) ||
- !list_empty(&current->signal->cpu_timers[2])) {
- /*
- * Have child wake up on its first tick to check
- * for process CPU timers.
- */
- p->it_prof_expires = jiffies_to_cputime(1);
- }
}
if (likely(p->pid)) {
@@ -1254,6 +1271,8 @@ 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);
@@ -1261,8 +1280,6 @@ 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);
@@ -1278,8 +1295,6 @@ 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);
@@ -1292,9 +1307,9 @@ 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:
@@ -1338,6 +1353,21 @@ long do_fork(unsigned long clone_flags,
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
*/
if (unlikely(clone_flags & CLONE_STOPPED)) {
@@ -1369,6 +1399,8 @@ long do_fork(unsigned long clone_flags,
if (!IS_ERR(p)) {
struct completion vfork;
+ trace_sched_process_fork(current, p);
+
nr = task_pid_vnr(p);
if (clone_flags & CLONE_PARENT_SETTID)
@@ -1379,6 +1411,7 @@ long do_fork(unsigned long clone_flags,
init_completion(&vfork);
}
+ audit_finish_fork(p);
tracehook_report_clone(trace, regs, clone_flags, nr, p);
/*
@@ -1582,8 +1615,7 @@ 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;
/*
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