diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/uprobes.c | 35 | ||||
| -rw-r--r-- | kernel/trace/trace_uprobe.c | 46 |
2 files changed, 47 insertions, 34 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index d1edc5e..3b02c72 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -127,7 +127,7 @@ struct xol_area { */ static bool valid_vma(struct vm_area_struct *vma, bool is_register) { - vm_flags_t flags = VM_HUGETLB | VM_MAYEXEC | VM_SHARED; + vm_flags_t flags = VM_HUGETLB | VM_MAYEXEC | VM_MAYSHARE; if (is_register) flags |= VM_WRITE; @@ -279,18 +279,13 @@ static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t * supported by that architecture then we need to modify is_trap_at_addr and * uprobe_write_opcode accordingly. This would never be a problem for archs * that have fixed length instructions. - */ - -/* + * * uprobe_write_opcode - write the opcode at a given virtual address. * @mm: the probed process address space. * @vaddr: the virtual address to store the opcode. * @opcode: opcode to be written at @vaddr. * - * Called with mm->mmap_sem held (for read and with a reference to - * mm). - * - * For mm @mm, write the opcode at @vaddr. + * Called with mm->mmap_sem held for write. * Return 0 (success) or a negative errno. */ int uprobe_write_opcode(struct mm_struct *mm, unsigned long vaddr, @@ -310,21 +305,25 @@ retry: if (ret <= 0) goto put_old; + ret = anon_vma_prepare(vma); + if (ret) + goto put_old; + ret = -ENOMEM; new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, vaddr); if (!new_page) goto put_old; - __SetPageUptodate(new_page); + if (mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL)) + goto put_new; + __SetPageUptodate(new_page); copy_highpage(new_page, old_page); copy_to_page(new_page, vaddr, &opcode, UPROBE_SWBP_INSN_SIZE); - ret = anon_vma_prepare(vma); - if (ret) - goto put_new; - ret = __replace_page(vma, vaddr, old_page, new_page); + if (ret) + mem_cgroup_uncharge_page(new_page); put_new: page_cache_release(new_page); @@ -1352,6 +1351,16 @@ unsigned long __weak uprobe_get_swbp_addr(struct pt_regs *regs) return instruction_pointer(regs) - UPROBE_SWBP_INSN_SIZE; } +unsigned long uprobe_get_trap_addr(struct pt_regs *regs) +{ + struct uprobe_task *utask = current->utask; + + if (unlikely(utask && utask->active_uprobe)) + return utask->vaddr; + + return instruction_pointer(regs); +} + /* * Called with no locks held. * Called in context of a exiting or a exec-ing thread. diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index c082a74..5a7f1a6 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -1009,56 +1009,60 @@ uprobe_filter_event(struct trace_uprobe *tu, struct perf_event *event) return __uprobe_perf_filter(&tu->filter, event->hw.tp_target->mm); } -static int uprobe_perf_open(struct trace_uprobe *tu, struct perf_event *event) +static int uprobe_perf_close(struct trace_uprobe *tu, struct perf_event *event) { bool done; write_lock(&tu->filter.rwlock); if (event->hw.tp_target) { - /* - * event->parent != NULL means copy_process(), we can avoid - * uprobe_apply(). current->mm must be probed and we can rely - * on dup_mmap() which preserves the already installed bp's. - * - * attr.enable_on_exec means that exec/mmap will install the - * breakpoints we need. - */ + list_del(&event->hw.tp_list); done = tu->filter.nr_systemwide || - event->parent || event->attr.enable_on_exec || + (event->hw.tp_target->flags & PF_EXITING) || uprobe_filter_event(tu, event); - list_add(&event->hw.tp_list, &tu->filter.perf_events); } else { + tu->filter.nr_systemwide--; done = tu->filter.nr_systemwide; - tu->filter.nr_systemwide++; } write_unlock(&tu->filter.rwlock); if (!done) - uprobe_apply(tu->inode, tu->offset, &tu->consumer, true); + return uprobe_apply(tu->inode, tu->offset, &tu->consumer, false); return 0; } -static int uprobe_perf_close(struct trace_uprobe *tu, struct perf_event *event) +static int uprobe_perf_open(struct trace_uprobe *tu, struct perf_event *event) { bool done; + int err; write_lock(&tu->filter.rwlock); if (event->hw.tp_target) { - list_del(&event->hw.tp_list); + /* + * event->parent != NULL means copy_process(), we can avoid + * uprobe_apply(). current->mm must be probed and we can rely + * on dup_mmap() which preserves the already installed bp's. + * + * attr.enable_on_exec means that exec/mmap will install the + * breakpoints we need. + */ done = tu->filter.nr_systemwide || - (event->hw.tp_target->flags & PF_EXITING) || + event->parent || event->attr.enable_on_exec || uprobe_filter_event(tu, event); + list_add(&event->hw.tp_list, &tu->filter.perf_events); } else { - tu->filter.nr_systemwide--; done = tu->filter.nr_systemwide; + tu->filter.nr_systemwide++; } write_unlock(&tu->filter.rwlock); - if (!done) - uprobe_apply(tu->inode, tu->offset, &tu->consumer, false); - - return 0; + err = 0; + if (!done) { + err = uprobe_apply(tu->inode, tu->offset, &tu->consumer, true); + if (err) + uprobe_perf_close(tu, event); + } + return err; } static bool uprobe_perf_filter(struct uprobe_consumer *uc, |
