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

4 files changed, 24 insertions, 4 deletions

diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index 771c96afe1d5..c91543a617ac 100644
--- a/security/selinux/ss/conditional.c
+++ b/security/selinux/ss/conditional.c
@@ -361,7 +361,6 @@ static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list *
 
 	*ret_list = NULL;
 
-	len = 0;
 	rc = next_entry(buf, fp, sizeof(u32));
 	if (rc)
 		return rc;
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);
+}
diff --git a/security/selinux/ss/hashtab.h b/security/selinux/ss/hashtab.h
index 3e3e42bfd150..6183ee2a2e7a 100644
--- a/security/selinux/ss/hashtab.h
+++ b/security/selinux/ss/hashtab.h
@@ -85,4 +85,8 @@ int hashtab_map(struct hashtab *h,
 /* Fill info with some hash table statistics */
 void hashtab_stat(struct hashtab *h, struct hashtab_info *info);
 
+/* Use kmem_cache for hashtab_node */
+void hashtab_cache_init(void);
+void hashtab_cache_destroy(void);
+
 #endif	/* _SS_HASHTAB_H */
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index e4a1c0dc561a..33cfe5d3d6cb 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -2060,10 +2060,12 @@ int security_load_policy(void *data, size_t len)
 	if (!ss_initialized) {
 		avtab_cache_init();
 		ebitmap_cache_init();
+		hashtab_cache_init();
 		rc = policydb_read(&policydb, fp);
 		if (rc) {
 			avtab_cache_destroy();
 			ebitmap_cache_destroy();
+			hashtab_cache_destroy();
 			goto out;
 		}
 
@@ -2075,6 +2077,7 @@ int security_load_policy(void *data, size_t len)
 			policydb_destroy(&policydb);
 			avtab_cache_destroy();
 			ebitmap_cache_destroy();
+			hashtab_cache_destroy();
 			goto out;
 		}
 
@@ -2083,6 +2086,7 @@ int security_load_policy(void *data, size_t len)
 			policydb_destroy(&policydb);
 			avtab_cache_destroy();
 			ebitmap_cache_destroy();
+			hashtab_cache_destroy();
 			goto out;
 		}