selinux: refactor sidtab conversion

This is a purely cosmetic change that encapsulates the three-step sidtab
conversion logic (shutdown -> clone -> map) into a single function
defined in sidtab.c (as opposed to services.c).

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: whitespaces fixes to make checkpatch happy]
Signed-off-by: Paul Moore <paul@paul-moore.com>

3 files changed, 42 insertions, 41 deletions

diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index 12e414394530..7337db24a6a8 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -1880,19 +1880,6 @@ int security_change_sid(struct selinux_state *state,
                                     out_sid, false);
 }
 
-/* Clone the SID into the new SID table. */
-static int clone_sid(u32 sid,
-                     struct context *context,
-                     void *arg)
-{
-        struct sidtab *s = arg;
-
-        if (sid > SECINITSID_NUM)
-                return sidtab_insert(s, sid, context);
-        else
-                return 0;
-}
-
 static inline int convert_context_handle_invalid_context(
         struct selinux_state *state,
         struct context *context)
@@ -2186,13 +2173,6 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len)
                 goto err;
         }
 
-        /* Clone the SID table. */
-        sidtab_shutdown(sidtab);
-
-        rc = sidtab_map(sidtab, clone_sid, &newsidtab);
-        if (rc)
-                goto err;
-
         /*
          * Convert the internal representations of contexts
          * in the new SID table.
@@ -2200,7 +2180,7 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len)
         args.state = state;
         args.oldp = policydb;
         args.newp = newpolicydb;
-        rc = sidtab_map(&newsidtab, convert_context, &args);
+        rc = sidtab_convert(sidtab, &newsidtab, convert_context, &args);
         if (rc) {
                 pr_err("SELinux:  unable to convert the internal"
                         " representation of contexts in the new SID"
diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c
index fd75a12fa8fc..ccc0ea230df4 100644
--- a/security/selinux/ss/sidtab.c
+++ b/security/selinux/ss/sidtab.c
@@ -116,11 +116,11 @@ struct context *sidtab_search_force(struct sidtab *s, u32 sid)
         return sidtab_search_core(s, sid, 1);
 }
 
-int sidtab_map(struct sidtab *s,
-               int (*apply) (u32 sid,
-                             struct context *context,
-                             void *args),
-               void *args)
+static int sidtab_map(struct sidtab *s,
+                      int (*apply)(u32 sid,
+                                   struct context *context,
+                                   void *args),
+                      void *args)
 {
         int i, rc = 0;
         struct sidtab_node *cur;
@@ -141,6 +141,37 @@ out:
         return rc;
 }
 
+/* Clone the SID into the new SID table. */
+static int clone_sid(u32 sid, struct context *context, void *arg)
+{
+        struct sidtab *s = arg;
+
+        if (sid > SECINITSID_NUM)
+                return sidtab_insert(s, sid, context);
+        else
+                return 0;
+}
+
+int sidtab_convert(struct sidtab *s, struct sidtab *news,
+                   int (*convert)(u32 sid,
+                                  struct context *context,
+                                  void *args),
+                   void *args)
+{
+        unsigned long flags;
+        int rc;
+
+        spin_lock_irqsave(&s->lock, flags);
+        s->shutdown = 1;
+        spin_unlock_irqrestore(&s->lock, flags);
+
+        rc = sidtab_map(s, clone_sid, news);
+        if (rc)
+                return rc;
+
+        return sidtab_map(news, convert, args);
+}
+
 static void sidtab_update_cache(struct sidtab *s, struct sidtab_node *n, int loc)
 {
         BUG_ON(loc >= SIDTAB_CACHE_LEN);
@@ -295,12 +326,3 @@ void sidtab_set(struct sidtab *dst, struct sidtab *src)
                 dst->cache[i] = NULL;
         spin_unlock_irqrestore(&src->lock, flags);
 }
-
-void sidtab_shutdown(struct sidtab *s)
-{
-        unsigned long flags;
-
-        spin_lock_irqsave(&s->lock, flags);
-        s->shutdown = 1;
-        spin_unlock_irqrestore(&s->lock, flags);
-}
diff --git a/security/selinux/ss/sidtab.h b/security/selinux/ss/sidtab.h
index a1a1d2617b6f..e1d1f0beb17c 100644
--- a/security/selinux/ss/sidtab.h
+++ b/security/selinux/ss/sidtab.h
@@ -37,11 +37,11 @@ int sidtab_insert(struct sidtab *s, u32 sid, struct context *context);
 struct context *sidtab_search(struct sidtab *s, u32 sid);
 struct context *sidtab_search_force(struct sidtab *s, u32 sid);
 
-int sidtab_map(struct sidtab *s,
-               int (*apply) (u32 sid,
-                             struct context *context,
-                             void *args),
-               void *args);
+int sidtab_convert(struct sidtab *s, struct sidtab *news,
+                   int (*apply)(u32 sid,
+                                struct context *context,
+                                void *args),
+                   void *args);
 
 int sidtab_context_to_sid(struct sidtab *s,
                           struct context *context,
@@ -50,7 +50,6 @@ int sidtab_context_to_sid(struct sidtab *s,
 void sidtab_hash_eval(struct sidtab *h, char *tag);
 void sidtab_destroy(struct sidtab *s);
 void sidtab_set(struct sidtab *dst, struct sidtab *src);
-void sidtab_shutdown(struct sidtab *s);
 
 #endif  /* _SS_SIDTAB_H_ */