diff options
Diffstat (limited to 'kernel/events')
| -rw-r--r-- | kernel/events/uprobes.c | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 5cbebac27c01..c38bf37d0aca 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -614,6 +614,18 @@ static int prepare_uprobe(struct uprobe *uprobe, struct file *file, return ret; } +static bool filter_chain(struct uprobe *uprobe) +{ + /* + * TODO: + * for_each_consumer(uc) + * if (uc->filter(...)) + * return true; + * return false; + */ + return uprobe->consumers != NULL; +} + static int install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, struct vm_area_struct *vma, unsigned long vaddr) @@ -624,11 +636,10 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, /* * If probe is being deleted, unregister thread could be done with * the vma-rmap-walk through. Adding a probe now can be fatal since - * nobody will be able to cleanup. Also we could be from fork or - * mremap path, where the probe might have already been inserted. - * Hence behave as if probe already existed. + * nobody will be able to cleanup. But in this case filter_chain() + * must return false, all consumers have gone away. */ - if (!uprobe->consumers) + if (!filter_chain(uprobe)) return 0; ret = prepare_uprobe(uprobe, vma->vm_file, mm, vaddr); @@ -655,10 +666,12 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, static int remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, unsigned long vaddr) { - /* can happen if uprobe_register() fails */ if (!test_bit(MMF_HAS_UPROBES, &mm->flags)) return 0; + if (filter_chain(uprobe)) + return 0; + set_bit(MMF_RECALC_UPROBES, &mm->flags); return set_orig_insn(&uprobe->arch, mm, vaddr); } @@ -1382,6 +1395,7 @@ static void mmf_recalc_uprobes(struct mm_struct *mm) * This is not strictly accurate, we can race with * uprobe_unregister() and see the already removed * uprobe if delete_uprobe() was not yet called. + * Or this uprobe can be filtered out. */ if (vma_has_uprobes(vma, vma->vm_start, vma->vm_end)) return; |