From 74d85dbec88016a13ab6d24ea0f63817f6554dbd Mon Sep 17 00:00:00 2001
From: Eric Paris <eparis@redhat.com>
Date: Wed, 13 Oct 2010 17:50:31 -0400
Subject: [PATCH] --- yaml --- r: 211685 b: refs/heads/master c:
 845ca30fe9691f1bab7cfbf30b6d11c944eb4abd h: refs/heads/master i:   211683:
 b328356a508dcbc4677b3b7370eb7f3988ea346b v: v3

---
 [refs]                               |  2 +-
 trunk/security/selinux/selinuxfs.c   | 44 ++++++++++++++++++++++++++++
 trunk/security/selinux/ss/services.c |  2 +-
 3 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 9615db054cf7..5de60898bd13 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: cee74f47a6baba0ac457e87687fdcf0abd599f0a
+refs/heads/master: 845ca30fe9691f1bab7cfbf30b6d11c944eb4abd
diff --git a/trunk/security/selinux/selinuxfs.c b/trunk/security/selinux/selinuxfs.c
index 8eb102c72606..87e0556bae70 100644
--- a/trunk/security/selinux/selinuxfs.c
+++ b/trunk/security/selinux/selinuxfs.c
@@ -439,9 +439,53 @@ static ssize_t sel_read_policy(struct file *filp, char __user *buf,
 	return ret;
 }
 
+static int sel_mmap_policy_fault(struct vm_area_struct *vma,
+				 struct vm_fault *vmf)
+{
+	struct policy_load_memory *plm = vma->vm_file->private_data;
+	unsigned long offset;
+	struct page *page;
+
+	if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
+		return VM_FAULT_SIGBUS;
+
+	offset = vmf->pgoff << PAGE_SHIFT;
+	if (offset >= roundup(plm->len, PAGE_SIZE))
+		return VM_FAULT_SIGBUS;
+
+	page = vmalloc_to_page(plm->data + offset);
+	get_page(page);
+
+	vmf->page = page;
+
+	return 0;
+}
+
+static struct vm_operations_struct sel_mmap_policy_ops = {
+	.fault = sel_mmap_policy_fault,
+	.page_mkwrite = sel_mmap_policy_fault,
+};
+
+int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
+{
+	if (vma->vm_flags & VM_SHARED) {
+		/* do not allow mprotect to make mapping writable */
+		vma->vm_flags &= ~VM_MAYWRITE;
+
+		if (vma->vm_flags & VM_WRITE)
+			return -EACCES;
+	}
+
+	vma->vm_flags |= VM_RESERVED;
+	vma->vm_ops = &sel_mmap_policy_ops;
+
+	return 0;
+}
+
 static const struct file_operations sel_policy_ops = {
 	.open		= sel_open_policy,
 	.read		= sel_read_policy,
+	.mmap		= sel_mmap_policy,
 	.release	= sel_release_policy,
 };
 
diff --git a/trunk/security/selinux/ss/services.c b/trunk/security/selinux/ss/services.c
index 7565d16aac31..3a1739b33b78 100644
--- a/trunk/security/selinux/ss/services.c
+++ b/trunk/security/selinux/ss/services.c
@@ -3169,7 +3169,7 @@ int security_read_policy(void **data, ssize_t *len)
 
 	*len = security_policydb_len();
 
-	*data = vmalloc(*len);
+	*data = vmalloc_user(*len);
 	if (!*data)
 		return -ENOMEM;