sched/membarrier: Return -ENOMEM to userspace on memory allocation failure

[linux.git] / kernel / signal.c

diff --git a/kernel/signal.c b/kernel/signal.c
index e667be6907d71333c44546cd43ebfdde6c9eab3c..c4da1ef56fdfcd7a522e403600c9786efc26bd94 100644 (file)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -90,6 +90,11 @@ static bool sig_task_ignored(struct task_struct *t, int sig, bool force)
            handler == SIG_DFL && !(force && sig_kernel_only(sig)))
                return true;
 
+       /* Only allow kernel generated signals to this kthread */
+       if (unlikely((t->flags & PF_KTHREAD) &&
+                    (handler == SIG_KTHREAD_KERNEL) && !force))
+               return true;
+
        return sig_handler_ignored(handler, sig);
 }
 
@@ -3673,8 +3678,11 @@ static int copy_siginfo_from_user_any(kernel_siginfo_t *kinfo, siginfo_t *info)
 
 static struct pid *pidfd_to_pid(const struct file *file)
 {
-       if (file->f_op == &pidfd_fops)
-               return file->private_data;
+       struct pid *pid;
+
+       pid = pidfd_pid(file);
+       if (!IS_ERR(pid))
+               return pid;
 
        return tgid_pidfd_to_pid(file);
 }