diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 7d12a45842a7..1c6cda68a555 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1366,12 +1366,55 @@ static struct uprobe_task *get_utask(void) return current->utask; } +static int dup_utask(struct task_struct *t, struct uprobe_task *o_utask) +{ + struct uprobe_task *n_utask; + struct return_instance **p, *o, *n; + + n_utask = kzalloc(sizeof(struct uprobe_task), GFP_KERNEL); + if (!n_utask) + return -ENOMEM; + t->utask = n_utask; + + p = &n_utask->return_instances; + for (o = o_utask->return_instances; o; o = o->next) { + n = kmalloc(sizeof(struct return_instance), GFP_KERNEL); + if (!n) + return -ENOMEM; + + *n = *o; + atomic_inc(&n->uprobe->ref); + n->next = NULL; + + *p = n; + p = &n->next; + n_utask->depth++; + } + + return 0; +} + +static void uprobe_warn(struct task_struct *t, const char *msg) +{ + pr_warn("uprobe: %s:%d failed to %s\n", + current->comm, current->pid, msg); +} + /* * Called in context of a new clone/fork from copy_process. */ void uprobe_copy_process(struct task_struct *t) { + struct uprobe_task *utask = current->utask; + struct mm_struct *mm = current->mm; + t->utask = NULL; + + if (mm == t->mm || !utask || !utask->return_instances) + return; + + if (dup_utask(t, utask)) + return uprobe_warn(t, "dup ret instances"); } /*