Merge branch 'linux-linaro-lsk-v4.4-android' of git://git.linaro.org/kernel/linux-linaro-stable.git

* linux-linaro-lsk-v4.4-android: (1212 commits)
  ANDROID: sdcardfs: Change current->fs under lock
  ANDROID: sdcardfs: Don't use OVERRIDE_CRED macro
  ANDROID: restrict store of prefer_idle as boolean
  BACKPORT: arm/syscalls: Optimize address limit check
  UPSTREAM: syscalls: Use CHECK_DATA_CORRUPTION for addr_limit_user_check
  BACKPORT: arm64/syscalls: Check address limit on user-mode return
  BACKPORT: x86/syscalls: Check address limit on user-mode return
  BACKPORT: lkdtm: add bad USER_DS test
  UPSTREAM: bug: switch data corruption check to __must_check
  BACKPORT: lkdtm: Add tests for struct list corruption
  UPSTREAM: bug: Provide toggle for BUG on data corruption
  UPSTREAM: list: Split list_del() debug checking into separate function
  UPSTREAM: rculist: Consolidate DEBUG_LIST for list_add_rcu()
  BACKPORT: list: Split list_add() debug checking into separate function
  FROMLIST: ANDROID: binder: Add BINDER_GET_NODE_INFO_FOR_REF ioctl.
  BACKPORT: arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW
  ANDROID: arm64: mm: fix 4.4.154 merge
  BACKPORT: zsmalloc: introduce zs_huge_class_size()
  BACKPORT: zram: drop max_zpage_size and use zs_huge_class_size()
  ANDROID: tracing: fix race condition reading saved tgids
  ...

Change-Id: I9f23db35eb926b6fa0d7af7dbbb55c9a37d536fc

1 files changed, 55 insertions, 0 deletions

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index d1dfbe34fa7c..d739baf6cad2 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -4655,6 +4655,42 @@ out:
 	return ret;
 }
 
+static int binder_ioctl_get_node_info_for_ref(struct binder_proc *proc,
+		struct binder_node_info_for_ref *info)
+{
+	struct binder_node *node;
+	struct binder_context *context = proc->context;
+	__u32 handle = info->handle;
+
+	if (info->strong_count || info->weak_count || info->reserved1 ||
+	    info->reserved2 || info->reserved3) {
+		binder_user_error("%d BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero.",
+				  proc->pid);
+		return -EINVAL;
+	}
+
+	/* This ioctl may only be used by the context manager */
+	mutex_lock(&context->context_mgr_node_lock);
+	if (!context->binder_context_mgr_node ||
+		context->binder_context_mgr_node->proc != proc) {
+		mutex_unlock(&context->context_mgr_node_lock);
+		return -EPERM;
+	}
+	mutex_unlock(&context->context_mgr_node_lock);
+
+	node = binder_get_node_from_ref(proc, handle, true, NULL);
+	if (!node)
+		return -EINVAL;
+
+	info->strong_count = node->local_strong_refs +
+		node->internal_strong_refs;
+	info->weak_count = node->local_weak_refs;
+
+	binder_put_node(node);
+
+	return 0;
+}
+
 static int binder_ioctl_get_node_debug_info(struct binder_proc *proc,
 				struct binder_node_debug_info *info) {
 	struct rb_node *n;
@@ -4748,6 +4784,25 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		}
 		break;
 	}
+	case BINDER_GET_NODE_INFO_FOR_REF: {
+		struct binder_node_info_for_ref info;
+
+		if (copy_from_user(&info, ubuf, sizeof(info))) {
+			ret = -EFAULT;
+			goto err;
+		}
+
+		ret = binder_ioctl_get_node_info_for_ref(proc, &info);
+		if (ret < 0)
+			goto err;
+
+		if (copy_to_user(ubuf, &info, sizeof(info))) {
+			ret = -EFAULT;
+			goto err;
+		}
+
+		break;
+	}
 	case BINDER_GET_NODE_DEBUG_INFO: {
 		struct binder_node_debug_info info;