From 7f62394deb9ffe9dcb4bda81daf76f4d5a06733e Mon Sep 17 00:00:00 2001
From: Ben Hutchings <ben@decadent.org.uk>
Date: Mon, 7 Sep 2020 02:51:53 +0100
Subject: [PATCH 1/2] Export symbols needed by Android drivers

We want to enable use of the Android ashmem and binder drivers to
support Anbox, but they should not be built-in as that would waste
resources and increase security attack surface on systems that don't
need them.

Export the currently un-exported symbols they depend on.
---
 fs/file.c           | 1 +
 kernel/fork.c       | 1 +
 kernel/sched/core.c | 1 +
 kernel/task_work.c  | 1 +
 mm/memory.c         | 1 +
 mm/shmem.c          | 1 +
 security/security.c | 4 ++++
 7 files changed, 10 insertions(+)

diff --git a/fs/file.c b/fs/file.c
index dab120b71e44..66f7ae2125b2 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -761,6 +761,7 @@ int close_fd_get_file(unsigned int fd, struct file **res)
 	*res = NULL;
 	return -ENOENT;
 }
+EXPORT_SYMBOL(close_fd_get_file);
 
 void do_close_on_exec(struct files_struct *files)
 {
diff --git a/kernel/fork.c b/kernel/fork.c
index d66cd1014211..ff215b3fdb15 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1120,6 +1120,7 @@ void mmput_async(struct mm_struct *mm)
 		schedule_work(&mm->async_put_work);
 	}
 }
+EXPORT_SYMBOL_GPL(mmput_async);
 #endif
 
 /**
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index ff74fca39ed2..943239122b29 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5575,6 +5575,7 @@ int can_nice(const struct task_struct *p, const int nice)
 	return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) ||
 		capable(CAP_SYS_NICE));
 }
+EXPORT_SYMBOL_GPL(can_nice);
 
 #ifdef __ARCH_WANT_SYS_NICE
 
diff --git a/kernel/task_work.c b/kernel/task_work.c
index 9cde961875c0..5c8dea45d4f8 100644
--- a/kernel/task_work.c
+++ b/kernel/task_work.c
@@ -57,6 +57,7 @@ int task_work_add(struct task_struct *task, struct callback_head *work,
 
 	return 0;
 }
+EXPORT_SYMBOL(task_work_add);
 
 /**
  * task_work_cancel - cancel a pending work added by task_work_add()
diff --git a/mm/memory.c b/mm/memory.c
index feff48e1465a..9e9b0fd92e38 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1542,6 +1542,7 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long start,
 	mmu_notifier_invalidate_range_end(&range);
 	tlb_finish_mmu(&tlb, start, range.end);
 }
+EXPORT_SYMBOL_GPL(zap_page_range);
 
 /**
  * zap_page_range_single - remove user pages in a given range
diff --git a/mm/shmem.c b/mm/shmem.c
index 7c6b6d8f6c39..83151e1345e6 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -4287,6 +4287,7 @@ int shmem_zero_setup(struct vm_area_struct *vma)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(shmem_zero_setup);
 
 /**
  * shmem_read_mapping_page_gfp - read into page cache, using specified page allocation flags.
diff --git a/security/security.c b/security/security.c
index 7b09cfbae94f..5eaec62c51f2 100644
--- a/security/security.c
+++ b/security/security.c
@@ -727,24 +727,28 @@ int security_binder_set_context_mgr(struct task_struct *mgr)
 {
 	return call_int_hook(binder_set_context_mgr, 0, mgr);
 }
+EXPORT_SYMBOL_GPL(security_binder_set_context_mgr);
 
 int security_binder_transaction(struct task_struct *from,
 				struct task_struct *to)
 {
 	return call_int_hook(binder_transaction, 0, from, to);
 }
+EXPORT_SYMBOL_GPL(security_binder_transaction);
 
 int security_binder_transfer_binder(struct task_struct *from,
 				    struct task_struct *to)
 {
 	return call_int_hook(binder_transfer_binder, 0, from, to);
 }
+EXPORT_SYMBOL_GPL(security_binder_transfer_binder);
 
 int security_binder_transfer_file(struct task_struct *from,
 				  struct task_struct *to, struct file *file)
 {
 	return call_int_hook(binder_transfer_file, 0, from, to, file);
 }
+EXPORT_SYMBOL_GPL(security_binder_transfer_file);
 
 int security_ptrace_access_check(struct task_struct *child, unsigned int mode)
 {
-- 
2.30.1