diff options
Diffstat (limited to 'kernel/events/uprobes.c')
| -rw-r--r-- | kernel/events/uprobes.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 1c6cda68a555..9f282e14925d 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -35,6 +35,7 @@ #include <linux/kdebug.h> /* notifier mechanism */ #include "../../mm/internal.h" /* munlock_vma_page */ #include <linux/percpu-rwsem.h> +#include <linux/task_work.h> #include <linux/uprobes.h> @@ -1400,6 +1401,17 @@ static void uprobe_warn(struct task_struct *t, const char *msg) current->comm, current->pid, msg); } +static void dup_xol_work(struct callback_head *work) +{ + kfree(work); + + if (current->flags & PF_EXITING) + return; + + if (!__create_xol_area(current->utask->vaddr)) + uprobe_warn(current, "dup xol area"); +} + /* * Called in context of a new clone/fork from copy_process. */ @@ -1407,6 +1419,8 @@ void uprobe_copy_process(struct task_struct *t) { struct uprobe_task *utask = current->utask; struct mm_struct *mm = current->mm; + struct callback_head *work; + struct xol_area *area; t->utask = NULL; @@ -1415,6 +1429,20 @@ void uprobe_copy_process(struct task_struct *t) if (dup_utask(t, utask)) return uprobe_warn(t, "dup ret instances"); + + /* The task can fork() after dup_xol_work() fails */ + area = mm->uprobes_state.xol_area; + if (!area) + return uprobe_warn(t, "dup xol area"); + + /* TODO: move it into the union in uprobe_task */ + work = kmalloc(sizeof(*work), GFP_KERNEL); + if (!work) + return uprobe_warn(t, "dup xol area"); + + utask->vaddr = area->vaddr; + init_task_work(work, dup_xol_work); + task_work_add(t, work, true); } /* |