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-rw-r--r--kernel/events/uprobes.c35
-rw-r--r--kernel/trace/trace_uprobe.c46
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,
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