Merge tag 'selinux-pr-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux updates from Paul Moore:
 "Seven SELinux patches for v4.15, although five of the seven are small
  build fixes and cleanups.

  Of the remaining two patches, the only one worth really calling out is
  Eric's fix for the SELinux filesystem xattr set/remove code; the other
  patch simply converts the SELinux hash table implementation to use
  kmem_cache.

  Eric's setxattr/removexattr tweak converts SELinux back to calling the
  commoncap implementations when the xattr is not SELinux related. The
  immediate win is to fixup filesystem capabilities in user namespaces,
  but it makes things a bit saner overall; more information in the
  commit description"

* tag 'selinux-pr-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: remove extraneous initialization of slots_used and max_chain_len
  selinux: remove redundant assignment to len
  selinux: remove redundant assignment to str
  selinux: fix build warning
  selinux: fix build warning by removing the unused sid variable
  selinux: Perform both commoncap and selinux xattr checks
  selinux: Use kmem_cache for hashtab_node

1 files changed, 16 insertions, 3 deletions

diff --git a/security/selinux/ss/hashtab.c b/security/selinux/ss/hashtab.c
index 6bd6dcd954fa..fe25b3fb2154 100644
--- a/security/selinux/ss/hashtab.c
+++ b/security/selinux/ss/hashtab.c
@@ -10,6 +10,8 @@
 #include <linux/sched.h>
 #include "hashtab.h"
 
+static struct kmem_cache *hashtab_node_cachep;
+
 struct hashtab *hashtab_create(u32 (*hash_value)(struct hashtab *h, const void *key),
 			       int (*keycmp)(struct hashtab *h, const void *key1, const void *key2),
 			       u32 size)
@@ -58,7 +60,7 @@ int hashtab_insert(struct hashtab *h, void *key, void *datum)
 	if (cur && (h->keycmp(h, key, cur->key) == 0))
 		return -EEXIST;
 
-	newnode = kzalloc(sizeof(*newnode), GFP_KERNEL);
+	newnode = kmem_cache_zalloc(hashtab_node_cachep, GFP_KERNEL);
 	if (!newnode)
 		return -ENOMEM;
 	newnode->key = key;
@@ -107,7 +109,7 @@ void hashtab_destroy(struct hashtab *h)
 		while (cur) {
 			temp = cur;
 			cur = cur->next;
-			kfree(temp);
+			kmem_cache_free(hashtab_node_cachep, temp);
 		}
 		h->htable[i] = NULL;
 	}
@@ -149,7 +151,7 @@ void hashtab_stat(struct hashtab *h, struct hashtab_info *info)
 
 	slots_used = 0;
 	max_chain_len = 0;
-	for (slots_used = max_chain_len = i = 0; i < h->size; i++) {
+	for (i = 0; i < h->size; i++) {
 		cur = h->htable[i];
 		if (cur) {
 			slots_used++;
@@ -167,3 +169,14 @@ void hashtab_stat(struct hashtab *h, struct hashtab_info *info)
 	info->slots_used = slots_used;
 	info->max_chain_len = max_chain_len;
 }
+void hashtab_cache_init(void)
+{
+		hashtab_node_cachep = kmem_cache_create("hashtab_node",
+			sizeof(struct hashtab_node),
+			0, SLAB_PANIC, NULL);
+}
+
+void hashtab_cache_destroy(void)
+{
+		kmem_cache_destroy(hashtab_node_cachep);
+}