xnu-6153.141.1.tar.gz

[apple/xnu.git] / bsd / vfs / vfs_cache.c

diff --git a/bsd/vfs/vfs_cache.c b/bsd/vfs/vfs_cache.c
index b027e9535ec7d725527ca713a10c65ab8ae4281b..e6a80232336fd0263d435be524f65c2dc925885c 100644 (file)
--- a/bsd/vfs/vfs_cache.c
+++ b/bsd/vfs/vfs_cache.c
@@ -428,12 +428,14 @@ vnode_issubdir(vnode_t vp, vnode_t dvp, int *is_subdir, vfs_context_t ctx)
  *
  */
 int
-build_path_with_parent(vnode_t first_vp, vnode_t parent_vp, char *buff, int buflen, int *outlen, int flags, vfs_context_t ctx)
+build_path_with_parent(vnode_t first_vp, vnode_t parent_vp, char *buff, int buflen,
+    int *outlen, size_t *mntpt_outlen, int flags, vfs_context_t ctx)
 {
        vnode_t vp, tvp;
        vnode_t vp_with_iocount;
        vnode_t proc_root_dir_vp;
        char *end;
+       char *mntpt_end;
        const char *str;
        int  len;
        int  ret = 0;
@@ -462,6 +464,7 @@ again:
 
        end = &buff[buflen - 1];
        *end = '\0';
+       mntpt_end = NULL;
 
        /*
         * holding the NAME_CACHE_LOCK in shared mode is
@@ -520,6 +523,9 @@ again:
                                goto out_unlock;
                        } else {
                                vp = vp->v_mount->mnt_vnodecovered;
+                               if (!mntpt_end && vp) {
+                                       mntpt_end = end;
+                               }
                        }
                }
        }
@@ -761,6 +767,9 @@ bad_news:
                                tvp = NULL;
                        } else {
                                tvp = tvp->v_mount->mnt_vnodecovered;
+                               if (!mntpt_end && tvp) {
+                                       mntpt_end = end;
+                               }
                        }
                }
                if (tvp == NULLVP) {
@@ -782,7 +791,10 @@ out:
        /*
         * length includes the trailing zero byte
         */
-       *outlen = &buff[buflen] - end;
+       *outlen = (int)(&buff[buflen] - end);
+       if (mntpt_outlen && mntpt_end) {
+               *mntpt_outlen = (size_t)*outlen - (size_t)(&buff[buflen] - mntpt_end);
+       }
 
        /* One of the parents was moved during path reconstruction.
         * The caller is interested in knowing whether any of the
@@ -798,7 +810,7 @@ out:
 int
 build_path(vnode_t first_vp, char *buff, int buflen, int *outlen, int flags, vfs_context_t ctx)
 {
-       return build_path_with_parent(first_vp, NULL, buff, buflen, outlen, flags, ctx);
+       return build_path_with_parent(first_vp, NULL, buff, buflen, outlen, NULL, flags, ctx);
 }
 
 /*