diff options
| -rw-r--r-- | kernel/fork.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 27f6a67f692e..7dc86b50f925 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1265,9 +1265,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, posix_cpu_timers_init(p); - do_posix_clock_monotonic_gettime(&p->start_time); - p->real_start_time = p->start_time; - monotonic_to_bootbased(&p->real_start_time); p->io_context = NULL; p->audit_context = NULL; if (clone_flags & CLONE_THREAD) @@ -1423,6 +1420,18 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->task_works = NULL; /* + * From this point on we must avoid any synchronous user-space + * communication until we take the tasklist-lock. In particular, we do + * not want user-space to be able to predict the process start-time by + * stalling fork(2) after we recorded the start_time but before it is + * visible to the system. + */ + + do_posix_clock_monotonic_gettime(&p->start_time); + p->real_start_time = p->start_time; + monotonic_to_bootbased(&p->real_start_time); + + /* * Make it visible to the rest of the system, but dont wake it up yet. * Need tasklist lock for parent etc handling! */ |