4 files changed, 32 insertions, 4 deletions

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index dbc6aacd07a3..4fe23f28514e 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -3002,6 +3002,12 @@ static void binder_transaction(struct binder_proc *proc,
 			goto err_dead_binder;
 		}
 		e->to_node = target_node->debug_id;
+		if (WARN_ON(proc == target_proc)) {
+			return_error = BR_FAILED_REPLY;
+			return_error_param = -EINVAL;
+			return_error_line = __LINE__;
+			goto err_invalid_target_handle;
+		}
 		if (security_binder_transaction(proc->tsk,
 						target_proc->tsk) < 0) {
 			return_error = BR_FAILED_REPLY;
@@ -3655,10 +3661,17 @@ static int binder_thread_write(struct binder_proc *proc,
 				struct binder_node *ctx_mgr_node;
 				mutex_lock(&context->context_mgr_node_lock);
 				ctx_mgr_node = context->binder_context_mgr_node;
-				if (ctx_mgr_node)
+				if (ctx_mgr_node) {
+					if (ctx_mgr_node->proc == proc) {
+						binder_user_error("%d:%d context manager tried to acquire desc 0\n",
+								  proc->pid, thread->pid);
+						mutex_unlock(&context->context_mgr_node_lock);
+						return -EINVAL;
+					}
 					ret = binder_inc_ref_for_node(
 							proc, ctx_mgr_node,
 							strong, NULL, &rdata);
+				}
 				mutex_unlock(&context->context_mgr_node_lock);
 			}
 			if (ret)
@@ -4706,8 +4719,15 @@ static struct binder_thread *binder_get_thread(struct binder_proc *proc)
 
 static void binder_free_proc(struct binder_proc *proc)
 {
+	struct binder_device *device;
+
 	BUG_ON(!list_empty(&proc->todo));
 	BUG_ON(!list_empty(&proc->delivered_death));
+	device = container_of(proc->context, struct binder_device, context);
+	if (refcount_dec_and_test(&device->ref)) {
+		kfree(proc->context->name);
+		kfree(device);
+	}
 	binder_alloc_deferred_release(&proc->alloc);
 	put_task_struct(proc->tsk);
 	binder_stats_deleted(BINDER_STAT_PROC);
@@ -5242,6 +5262,7 @@ static int binder_open(struct inode *nodp, struct file *filp)
 	else
 		binder_dev = container_of(filp->private_data,
 					  struct binder_device, miscdev);
+	refcount_inc(&binder_dev->ref);
 	proc->context = &binder_dev->context;
 	binder_alloc_init(&proc->alloc);
 
@@ -6061,6 +6082,7 @@ static int __init init_binder_device(const char *name)
 	binder_device->miscdev.minor = MISC_DYNAMIC_MINOR;
 	binder_device->miscdev.name = name;
 
+	refcount_set(&binder_device->ref, 1);
 	binder_device->context.binder_context_mgr_uid = INVALID_UID;
 	binder_device->context.name = name;
 	mutex_init(&binder_device->context.context_mgr_node_lock);
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index bb0a732cd98a..f8953fcbcc0e 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -948,7 +948,7 @@ enum lru_status binder_alloc_free_page(struct list_head *item,
 		trace_binder_unmap_user_end(alloc, index);
 	}
 	up_read(&mm->mmap_sem);
-	mmput(mm);
+	mmput_async(mm);
 
 	trace_binder_unmap_kernel_start(alloc, index);
 
diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h
index 045b3e42d98b..31da3d935039 100644
--- a/drivers/android/binder_internal.h
+++ b/drivers/android/binder_internal.h
@@ -8,6 +8,7 @@
 #include <linux/list.h>
 #include <linux/miscdevice.h>
 #include <linux/mutex.h>
+#include <linux/refcount.h>
 #include <linux/stddef.h>
 #include <linux/types.h>
 #include <linux/uidgid.h>
@@ -33,6 +34,7 @@ struct binder_device {
 	struct miscdevice miscdev;
 	struct binder_context context;
 	struct inode *binderfs_inode;
+	refcount_t ref;
 };
 
 extern const struct file_operations binder_fops;
diff --git a/drivers/android/binderfs.c b/drivers/android/binderfs.c
index e773f45d19d9..67982cabe068 100644
--- a/drivers/android/binderfs.c
+++ b/drivers/android/binderfs.c
@@ -176,6 +176,7 @@ static int binderfs_binder_device_create(struct inode *ref_inode,
 	if (!name)
 		goto err;
 
+	refcount_set(&device->ref, 1);
 	device->binderfs_inode = inode;
 	device->context.binder_context_mgr_uid = INVALID_UID;
 	device->context.name = name;
@@ -280,8 +281,10 @@ static void binderfs_evict_inode(struct inode *inode)
 	ida_free(&binderfs_minors, device->miscdev.minor);
 	mutex_unlock(&binderfs_minors_mutex);
 
-	kfree(device->context.name);
-	kfree(device);
+	if (refcount_dec_and_test(&device->ref)) {
+		kfree(device->context.name);
+		kfree(device);
+	}
 }
 
 /**
@@ -436,6 +439,7 @@ static int binderfs_binder_ctl_create(struct super_block *sb)
 	inode->i_uid = info->root_uid;
 	inode->i_gid = info->root_gid;
 
+	refcount_set(&device->ref, 1);
 	device->binderfs_inode = inode;
 	device->miscdev.minor = minor;