xnu-3789.41.3.tar.gz

[apple/xnu.git] / security / mac_vfs_subr.c

diff --git a/security/mac_vfs_subr.c b/security/mac_vfs_subr.c
index e418342b056b1982084d2c4c6babf31cad7a8cb8..f8b2263b90ebb662cb1aaab739f0e5b132d7b283 100644 (file)
--- a/security/mac_vfs_subr.c
+++ b/security/mac_vfs_subr.c
@@ -34,34 +34,44 @@
 #include <sys/mount_internal.h>
 #include <sys/uio_internal.h>
 #include <sys/xattr.h>
+#include "../bsd/sys/fsevents.h"
 
 #include <security/mac_internal.h>
 
 /*
- * Caller holds reference or sets VNODE_LABEL_NEEDREF to non-zero.
- *
- * Function will drop lock and reference on return.
+ * Caller holds I/O reference on vnode
  */
 int
 vnode_label(struct mount *mp, struct vnode *dvp, struct vnode *vp,
            struct componentname *cnp, int flags, vfs_context_t ctx)
 {
-       int error;
+       int error = 0;
 
-       error = 0;
 
-       vnode_lock(vp);
+       /* fast path checks... */
 
-       if (vp->v_lflag & VL_LABELED) {
-               if (!(flags & VNODE_LABEL_NEEDREF))
-                       vnode_put_locked(vp);
-               vnode_unlock(vp);
-               return (0);
+       /* are we labeling vnodes? If not still notify of create */
+       if (mac_label_vnodes == 0) {
+               if (flags & VNODE_LABEL_CREATE)
+                       error = mac_vnode_notify_create(ctx,
+                           mp, dvp, vp, cnp);
+               return 0;
        }
 
-       if ((flags & VNODE_LABEL_NEEDREF) && vnode_get_locked(vp)) {
+       /* if already VL_LABELED */
+       if (vp->v_lflag & VL_LABELED)
+               return (0);
+
+       vnode_lock_spin(vp);
+
+       /*
+        * must revalidate state once we hold the lock
+        * since we could have blocked and someone else
+        * has since labeled this vnode
+        */
+       if (vp->v_lflag & VL_LABELED) {
                vnode_unlock(vp);
-               return (ENOENT);
+               return (0);
        }
 
        if ((vp->v_lflag & VL_LABEL) == 0) {
@@ -69,12 +79,17 @@ vnode_label(struct mount *mp, struct vnode *dvp, struct vnode *vp,
 
                /* Could sleep on disk I/O, drop lock. */
                vnode_unlock(vp);
+
+               if (vp->v_label == NULL)
+                       vp->v_label = mac_vnode_label_alloc();
+
                if (flags & VNODE_LABEL_CREATE)
                        error = mac_vnode_notify_create(ctx,
                            mp, dvp, vp, cnp);
                else
                        error = mac_vnode_label_associate(mp, vp, ctx);
-               vnode_lock(vp);
+
+               vnode_lock_spin(vp);
 
                if ((error == 0) && (vp->v_flag & VNCACHEABLE))
                        vp->v_lflag |= VL_LABELED;
@@ -82,10 +97,8 @@ vnode_label(struct mount *mp, struct vnode *dvp, struct vnode *vp,
 
                if (vp->v_lflag & VL_LABELWAIT) {
                        vp->v_lflag &= ~VL_LABELWAIT;
-                       wakeup(vp->v_label);
+                       wakeup(&vp->v_label);
                }
-               vnode_put_locked(vp);
-               vnode_unlock(vp);
        } else {
                struct timespec ts;
 
@@ -94,18 +107,19 @@ vnode_label(struct mount *mp, struct vnode *dvp, struct vnode *vp,
 
                while (vp->v_lflag & VL_LABEL) {
                        vp->v_lflag |= VL_LABELWAIT;
-                       error = msleep(vp->v_label, &vp->v_lock, PVFS|PDROP,
-                           "vnode_label", &ts);
-                       vnode_lock(vp);
+
+                       error = msleep(&vp->v_label, &vp->v_lock, PVFS|PDROP,
+                                      "vnode_label", &ts);
+                       vnode_lock_spin(vp);
+
                        if (error == EWOULDBLOCK) {
                                vprint("vnode label timeout", vp);
                                break;
                        }
                }
                /* XXX: what should be done if labeling failed (above)? */
-               vnode_put_locked(vp);
-               vnode_unlock(vp);
        }
+       vnode_unlock(vp);
 
        return (error);
 }
@@ -126,7 +140,7 @@ vnode_relabel(struct vnode *vp)
        /* Wait for any other labeling to complete. */
        while (vp->v_lflag & VL_LABEL) {
                vp->v_lflag |= VL_LABELWAIT;
-               (void)msleep(vp->v_label, &vp->v_lock, PVFS, "vnode_relabel", 0);
+               (void)msleep(&vp->v_label, &vp->v_lock, PVFS, "vnode_relabel", 0);
        }
 
        /* Clear labeled flag */
@@ -157,6 +171,13 @@ mac_vnop_setxattr (struct vnode *vp, const char *name, char *buf, size_t len)
        uio_addiov(auio, CAST_USER_ADDR_T(buf), len);
 
        error = vn_setxattr(vp, name, auio, options, ctx);
+#if CONFIG_FSE
+       if (error == 0) {
+               add_fsevent(FSE_XATTR_MODIFIED, ctx,
+                   FSE_ARG_VNODE, vp,
+                   FSE_ARG_DONE);
+       }
+#endif
 
        return (error);
 }
@@ -192,6 +213,13 @@ mac_vnop_removexattr (struct vnode *vp, const char *name)
                return (EROFS);
 
        error = vn_removexattr(vp, name, options, ctx);
+#if CONFIG_FSE
+       if (error == 0) {
+               add_fsevent(FSE_XATTR_REMOVED, ctx,
+                   FSE_ARG_VNODE, vp,
+                   FSE_ARG_DONE);
+       }
+#endif
 
        return (error);
 }