|
@@ -579,6 +579,11 @@ static int prepare_uprobe(struct uprobe *uprobe, struct file *file,
|
|
|
return ret;
|
|
|
}
|
|
|
|
|
|
+static inline bool consumer_filter(struct uprobe_consumer *uc)
|
|
|
+{
|
|
|
+ return true; /* TODO: !uc->filter || uc->filter(...) */
|
|
|
+}
|
|
|
+
|
|
|
static bool filter_chain(struct uprobe *uprobe)
|
|
|
{
|
|
|
struct uprobe_consumer *uc;
|
|
@@ -586,8 +591,7 @@ static bool filter_chain(struct uprobe *uprobe)
|
|
|
|
|
|
down_read(&uprobe->consumer_rwsem);
|
|
|
for (uc = uprobe->consumers; uc; uc = uc->next) {
|
|
|
- /* TODO: ret = uc->filter(...) */
|
|
|
- ret = true;
|
|
|
+ ret = consumer_filter(uc);
|
|
|
if (ret)
|
|
|
break;
|
|
|
}
|
|
@@ -603,15 +607,6 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
|
|
|
bool first_uprobe;
|
|
|
int ret;
|
|
|
|
|
|
- /*
|
|
|
- * 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. But in this case filter_chain()
|
|
|
- * must return false, all consumers have gone away.
|
|
|
- */
|
|
|
- if (!filter_chain(uprobe))
|
|
|
- return 0;
|
|
|
-
|
|
|
ret = prepare_uprobe(uprobe, vma->vm_file, mm, vaddr);
|
|
|
if (ret)
|
|
|
return ret;
|
|
@@ -636,12 +631,6 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
|
|
|
static int
|
|
|
remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, unsigned long vaddr)
|
|
|
{
|
|
|
- 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);
|
|
|
}
|
|
@@ -781,10 +770,14 @@ static int register_for_each_vma(struct uprobe *uprobe, bool is_register)
|
|
|
vaddr_to_offset(vma, info->vaddr) != uprobe->offset)
|
|
|
goto unlock;
|
|
|
|
|
|
- if (is_register)
|
|
|
- err = install_breakpoint(uprobe, mm, vma, info->vaddr);
|
|
|
- else
|
|
|
- err |= remove_breakpoint(uprobe, mm, info->vaddr);
|
|
|
+ if (is_register) {
|
|
|
+ /* consult only the "caller", new consumer. */
|
|
|
+ if (consumer_filter(uprobe->consumers))
|
|
|
+ err = install_breakpoint(uprobe, mm, vma, info->vaddr);
|
|
|
+ } else if (test_bit(MMF_HAS_UPROBES, &mm->flags)) {
|
|
|
+ if (!filter_chain(uprobe))
|
|
|
+ err |= remove_breakpoint(uprobe, mm, info->vaddr);
|
|
|
+ }
|
|
|
|
|
|
unlock:
|
|
|
up_write(&mm->mmap_sem);
|
|
@@ -968,9 +961,14 @@ int uprobe_mmap(struct vm_area_struct *vma)
|
|
|
|
|
|
mutex_lock(uprobes_mmap_hash(inode));
|
|
|
build_probe_list(inode, vma, vma->vm_start, vma->vm_end, &tmp_list);
|
|
|
-
|
|
|
+ /*
|
|
|
+ * We can race with uprobe_unregister(), this uprobe can be already
|
|
|
+ * removed. But in this case filter_chain() must return false, all
|
|
|
+ * consumers have gone away.
|
|
|
+ */
|
|
|
list_for_each_entry_safe(uprobe, u, &tmp_list, pending_list) {
|
|
|
- if (!fatal_signal_pending(current)) {
|
|
|
+ if (!fatal_signal_pending(current) &&
|
|
|
+ filter_chain(uprobe)) {
|
|
|
unsigned long vaddr = offset_to_vaddr(vma, uprobe->offset);
|
|
|
install_breakpoint(uprobe, vma->vm_mm, vma, vaddr);
|
|
|
}
|