Assign integer IDs to ncr.h contexts

2 files changed, 24 insertions, 0 deletions

diff --git a/crypto/userspace/ncr-int.h b/crypto/userspace/ncr-int.h
index 42c500f83da..60e2f080fff 100644
--- a/crypto/userspace/ncr-int.h
+++ b/crypto/userspace/ncr-int.h
@@ -108,6 +108,8 @@ struct key_item_st {
  * are here.
  */
 struct ncr_lists {
+	int id;			/* Used only for auditing */
+
 	struct mutex key_idr_mutex;
 	struct idr key_idr;
 
diff --git a/crypto/userspace/ncr.c b/crypto/userspace/ncr.c
index e643fe139a0..6cae7167c9d 100644
--- a/crypto/userspace/ncr.c
+++ b/crypto/userspace/ncr.c
@@ -26,6 +26,7 @@
 #include <linux/crypto.h>
 #include <linux/ioctl.h>
 #include <linux/mm.h>
+#include <linux/mutex.h>
 #include <linux/highmem.h>
 #include <linux/random.h>
 #include <linux/uaccess.h>
@@ -42,6 +43,9 @@
  */
 struct key_item_st master_key;
 
+static struct mutex lists_ida_mutex;
+static DEFINE_IDA(lists_ida);
+
 void* ncr_init_lists(void)
 {
 	struct ncr_lists *lst;
@@ -54,6 +58,19 @@ void* ncr_init_lists(void)
 
 	memset(lst, 0, sizeof(*lst));
 
+	mutex_init(&lists_ida_mutex);
+	mutex_lock(&lists_ida_mutex);
+	/* ida_pre_get() should preallocate enough, and, due to lists_ida_mutex,
+	   nobody else can use the preallocated data.  Therefore the loop
+	   recommended in idr_get_new() documentation is not necessary. */
+	if (ida_pre_get(&lists_ida, GFP_KERNEL) == 0 ||
+	    ida_get_new(&lists_ida, &lst->id) != 0) {
+		mutex_unlock(&lists_ida_mutex);
+		kfree(lst);
+		return NULL;
+	}
+	mutex_unlock(&lists_ida_mutex);
+
 	mutex_init(&lst->key_idr_mutex);
 	idr_init(&lst->key_idr);
 
@@ -68,6 +85,11 @@ void ncr_deinit_lists(struct ncr_lists *lst)
 	if(lst) {
 		ncr_key_list_deinit(lst);
 		ncr_sessions_list_deinit(lst);
+
+		mutex_lock(&lists_ida_mutex);
+		ida_remove(&lists_ida, lst->id);
+		mutex_unlock(&lists_ida_mutex);
+
 		kfree(lst);
 	}
 }