diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index c9f1e1e56b158..d3538b6c08312 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1472,9 +1472,15 @@ static vm_fault_t xol_fault(const struct vm_special_mapping *sm, return 0; } +static int xol_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) +{ + return -EPERM; +} + static const struct vm_special_mapping xol_mapping = { .name = "[uprobes]", .fault = xol_fault, + .mremap = xol_mremap, }; /* Slot allocation for XOL */ @@ -1667,21 +1673,19 @@ static void xol_free_insn_slot(struct uprobe_task *utask) { struct xol_area *area = current->mm->uprobes_state.xol_area; unsigned long offset = utask->xol_vaddr - area->vaddr; + unsigned int slot_nr; utask->xol_vaddr = 0; - /* - * xol_vaddr must fit into [area->vaddr, area->vaddr + PAGE_SIZE). - * This check can only fail if the "[uprobes]" vma was mremap'ed. - */ - if (offset < PAGE_SIZE) { - int slot_nr = offset / UPROBE_XOL_SLOT_BYTES; - - clear_bit(slot_nr, area->bitmap); - atomic_dec(&area->slot_count); - smp_mb__after_atomic(); /* pairs with prepare_to_wait() */ - if (waitqueue_active(&area->wq)) - wake_up(&area->wq); - } + /* xol_vaddr must fit into [area->vaddr, area->vaddr + PAGE_SIZE) */ + if (WARN_ON_ONCE(offset >= PAGE_SIZE)) + return; + + slot_nr = offset / UPROBE_XOL_SLOT_BYTES; + clear_bit(slot_nr, area->bitmap); + atomic_dec(&area->slot_count); + smp_mb__after_atomic(); /* pairs with prepare_to_wait() */ + if (waitqueue_active(&area->wq)) + wake_up(&area->wq); } void __weak arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr,