From 2cd850987436405547384feb707200c7dad4a675 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/sched/core.c | 1 +
 kernel/sched/wait.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 7893ea161d770..066f90a4f572f 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -814,6 +814,7 @@ struct file *close_fd_get_file(unsigned int fd)
 
 	return file;
 }
+EXPORT_SYMBOL_GPL(close_fd_get_file);
 
 void do_close_on_exec(struct files_struct *files)
 {
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0d18c3969f904..d1e20b1aad9c3 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7183,6 +7183,7 @@ static bool is_nice_reduction(const struct task_struct *p, const int nice)
 
 	return (nice_rlim <= task_rlimit(p, RLIMIT_NICE));
 }
+EXPORT_SYMBOL_GPL(can_nice);
 
 /*
  * can_nice - check if a task can reduce its nice value
diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c
index 133b74730738b..a2a3381ede737 100644
--- a/kernel/sched/wait.c
+++ b/kernel/sched/wait.c
@@ -247,6 +247,7 @@ void __wake_up_pollfree(struct wait_queue_head *wq_head)
 	/* POLLFREE must have cleared the queue. */
 	WARN_ON_ONCE(waitqueue_active(wq_head));
 }
+EXPORT_SYMBOL_GPL(__wake_up_pollfree);
 
 /*
  * Note: we use "set_current_state()" _after_ the wait-queue add,
diff --git a/kernel/task_work.c b/kernel/task_work.c
index 065e1ef8fc8d7..7d06ea82a53e4 100644
--- a/kernel/task_work.c
+++ b/kernel/task_work.c
@@ -73,6 +73,7 @@ int task_work_add(struct task_struct *task, struct callback_head *work,
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(task_work_add);
 
 /**
  * task_work_cancel_match - cancel a pending work added by task_work_add()
diff --git a/mm/memory.c b/mm/memory.c
index 01a23ad48a042..8762b48854243 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1728,6 +1728,7 @@ void zap_page_range_single(struct vm_area_struct *vma, unsigned long address,
 	mmu_notifier_invalidate_range_end(&range);
 	tlb_finish_mmu(&tlb);
 }
+EXPORT_SYMBOL_GPL(zap_page_range_single);
 
 /**
  * zap_vma_ptes - remove ptes mapping the vma
diff --git a/mm/shmem.c b/mm/shmem.c
index 448f393d8ab2b..b14ac0867f27d 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -4318,6 +4318,7 @@ int shmem_zero_setup(struct vm_area_struct *vma)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(shmem_zero_setup);
 
 /**
  * shmem_read_folio_gfp - read into page cache, using specified page allocation flags.
diff --git a/security/security.c b/security/security.c
index cf6cc576736f3..5401a0c5a1472 100644
--- a/security/security.c
+++ b/security/security.c
@@ -782,24 +782,28 @@ int security_binder_set_context_mgr(const struct cred *mgr)
 {
 	return call_int_hook(binder_set_context_mgr, 0, mgr);
 }
+EXPORT_SYMBOL_GPL(security_binder_set_context_mgr);
 
 int security_binder_transaction(const struct cred *from,
 				const struct cred *to)
 {
 	return call_int_hook(binder_transaction, 0, from, to);
 }
+EXPORT_SYMBOL_GPL(security_binder_transaction);
 
 int security_binder_transfer_binder(const struct cred *from,
 				    const struct cred *to)
 {
 	return call_int_hook(binder_transfer_binder, 0, from, to);
 }
+EXPORT_SYMBOL_GPL(security_binder_transfer_binder);
 
 int security_binder_transfer_file(const struct cred *from,
 				  const struct cred *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)
 {
-- 
2.40.1