SELinux: pass a superblock to security_fs_use

Rather than passing pointers to memory locations, strings, and other
stuff just give up on the separation and give security_fs_use the
superblock.  It just makes the code easier to read (even if not easier to
reuse on some other OS)

Signed-off-by: Eric Paris <eparis@redhat.com>

3 files changed, 11 insertions, 15 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 5596dc51e21b..ec15a5694b9e 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -677,7 +677,7 @@ static int selinux_set_mnt_opts(struct super_block *sb,
                 sbsec->flags |= SE_SBPROC;
 
         /* Determine the labeling behavior to use for this filesystem type. */
-        rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
+        rc = security_fs_use(sb);
         if (rc) {
                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
                        __func__, sb->s_type->name, rc);
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index 1a73fcd51d56..01a0382c43ca 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -171,8 +171,7 @@ int security_get_allow_unknown(void);
 #define SECURITY_FS_USE_NONE            5 /* no labeling support */
 #define SECURITY_FS_USE_MNTPOINT        6 /* use mountpoint labeling */
 
-int security_fs_use(const char *fstype, short unsigned int *behavior,
-        u32 *sid);
+int security_fs_use(struct super_block *sb);
 
 int security_genfs_sid(const char *fstype, char *name, u16 sclass,
         u32 *sid);
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index 603c638434bb..a90721771615 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -2323,17 +2323,14 @@ out:
 
 /**
  * security_fs_use - Determine how to handle labeling for a filesystem.
- * @fstype: filesystem type
- * @behavior: labeling behavior
- * @sid: SID for filesystem (superblock)
+ * @sb: superblock in question
  */
-int security_fs_use(
-        const char *fstype,
-        short unsigned int *behavior,
-        u32 *sid)
+int security_fs_use(struct super_block *sb)
 {
         int rc = 0;
         struct ocontext *c;
+        struct superblock_security_struct *sbsec = sb->s_security;
+        const char *fstype = sb->s_type->name;
 
         read_lock(&policy_rwlock);
 
@@ -2345,21 +2342,21 @@ int security_fs_use(
         }
 
         if (c) {
-                *behavior = c->v.behavior;
+                sbsec->behavior = c->v.behavior;
                 if (!c->sid[0]) {
                         rc = sidtab_context_to_sid(&sidtab, &c->context[0],
                                                    &c->sid[0]);
                         if (rc)
                                 goto out;
                 }
-                *sid = c->sid[0];
+                sbsec->sid = c->sid[0];
         } else {
-                rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
+                rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, &sbsec->sid);
                 if (rc) {
-                        *behavior = SECURITY_FS_USE_NONE;
+                        sbsec->behavior = SECURITY_FS_USE_NONE;
                         rc = 0;
                 } else {
-                        *behavior = SECURITY_FS_USE_GENFS;
+                        sbsec->behavior = SECURITY_FS_USE_GENFS;
                 }
         }