diff options
Diffstat (limited to 'kernel/sys.c')
| -rw-r--r-- | kernel/sys.c | 25 |
1 files changed, 14 insertions, 11 deletions
diff --git a/kernel/sys.c b/kernel/sys.c index d37d1f882b7d..374f83e95239 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1441,13 +1441,7 @@ static int do_prlimit(struct task_struct *tsk, unsigned int resource, return -EPERM; } - /* protect tsk->signal and tsk->sighand from disappearing */ - read_lock(&tasklist_lock); - if (!tsk->sighand) { - retval = -ESRCH; - goto out; - } - + /* Holding a refcount on tsk protects tsk->signal from disappearing. */ rlim = tsk->signal->rlim + resource; task_lock(tsk->group_leader); if (new_rlim) { @@ -1476,10 +1470,19 @@ static int do_prlimit(struct task_struct *tsk, unsigned int resource, */ if (!retval && new_rlim && resource == RLIMIT_CPU && new_rlim->rlim_cur != RLIM_INFINITY && - IS_ENABLED(CONFIG_POSIX_TIMERS)) - update_rlimit_cpu(tsk, new_rlim->rlim_cur); -out: - read_unlock(&tasklist_lock); + IS_ENABLED(CONFIG_POSIX_TIMERS)) { + /* + * update_rlimit_cpu can fail if the task is exiting, but there + * may be other tasks in the thread group that are not exiting, + * and they need their cpu timers adjusted. + * + * The group_leader is the last task to be released, so if we + * cannot update_rlimit_cpu on it, then the entire process is + * exiting and we do not need to update at all. + */ + update_rlimit_cpu(tsk->group_leader, new_rlim->rlim_cur); + } + return retval; } |