+// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/kernel/fork.c
*
unsigned long total_forks; /* Handle normal Linux uptimes. */
int nr_threads; /* The idle threads do not count.. */
-int max_threads; /* tunable limit on nr_threads */
+static int max_threads; /* tunable limit on nr_threads */
DEFINE_PER_CPU(unsigned long, process_counts) = 0;
struct page *page = alloc_pages_node(node, THREADINFO_GFP,
THREAD_SIZE_ORDER);
- return page ? page_address(page) : NULL;
+ if (likely(page)) {
+ tsk->stack = page_address(page);
+ return tsk->stack;
+ }
+ return NULL;
#endif
}
#ifdef CONFIG_STACKPROTECTOR
tsk->stack_canary = get_random_canary();
#endif
+ if (orig->cpus_ptr == &orig->cpus_mask)
+ tsk->cpus_ptr = &tsk->cpus_mask;
/*
* One for us, one for whoever does the "release_task()" (usually
#endif
};
-/**
- * pidfd_create() - Create a new pid file descriptor.
- *
- * @pid: struct pid that the pidfd will reference
- *
- * This creates a new pid file descriptor with the O_CLOEXEC flag set.
- *
- * Note, that this function can only be called after the fd table has
- * been unshared to avoid leaking the pidfd to the new process.
- *
- * Return: On success, a cloexec pidfd is returned.
- * On error, a negative errno number will be returned.
- */
-static int pidfd_create(struct pid *pid)
-{
- int fd;
-
- fd = anon_inode_getfd("[pidfd]", &pidfd_fops, get_pid(pid),
- O_RDWR | O_CLOEXEC);
- if (fd < 0)
- put_pid(pid);
-
- return fd;
-}
-
static void __delayed_free_task(struct rcu_head *rhp)
{
struct task_struct *tsk = container_of(rhp, struct task_struct, rcu);
int pidfd = -1, retval;
struct task_struct *p;
struct multiprocess_signals delayed;
+ struct file *pidfile = NULL;
/*
* Don't allow sharing the root directory with processes in a different
}
if (clone_flags & CLONE_PIDFD) {
- int reserved;
-
/*
* - CLONE_PARENT_SETTID is useless for pidfds and also
* parent_tidptr is used to return pidfds.
if (clone_flags &
(CLONE_DETACHED | CLONE_PARENT_SETTID | CLONE_THREAD))
return ERR_PTR(-EINVAL);
-
- /*
- * Verify that parent_tidptr is sane so we can potentially
- * reuse it later.
- */
- if (get_user(reserved, parent_tidptr))
- return ERR_PTR(-EFAULT);
-
- if (reserved != 0)
- return ERR_PTR(-EINVAL);
}
/*
p->pagefault_disabled = 0;
#ifdef CONFIG_LOCKDEP
- p->lockdep_depth = 0; /* no locks held yet */
- p->curr_chain_key = 0;
- p->lockdep_recursion = 0;
lockdep_init_task(p);
#endif
* if the fd table isn't shared).
*/
if (clone_flags & CLONE_PIDFD) {
- retval = pidfd_create(pid);
+ retval = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
if (retval < 0)
goto bad_fork_free_pid;
pidfd = retval;
+
+ pidfile = anon_inode_getfile("[pidfd]", &pidfd_fops, pid,
+ O_RDWR | O_CLOEXEC);
+ if (IS_ERR(pidfile)) {
+ put_unused_fd(pidfd);
+ retval = PTR_ERR(pidfile);
+ goto bad_fork_free_pid;
+ }
+ get_pid(pid); /* held by pidfile now */
+
retval = put_user(pidfd, parent_tidptr);
if (retval)
goto bad_fork_put_pidfd;
*/
p->start_time = ktime_get_ns();
- p->real_start_time = ktime_get_boot_ns();
+ p->real_start_time = ktime_get_boottime_ns();
/*
* Make it visible to the rest of the system, but dont wake it up yet.
goto bad_fork_cancel_cgroup;
}
+ /* past the last point of failure */
+ if (pidfile)
+ fd_install(pidfd, pidfile);
init_task_pid_links(p);
if (likely(p->pid)) {
bad_fork_cgroup_threadgroup_change_end:
cgroup_threadgroup_change_end(current);
bad_fork_put_pidfd:
- if (clone_flags & CLONE_PIDFD)
- ksys_close(pidfd);
+ if (clone_flags & CLONE_PIDFD) {
+ fput(pidfile);
+ put_unused_fd(pidfd);
+ }
bad_fork_free_pid:
if (pid != &init_struct_pid)
free_pid(pid);