Return an error in 'mount' call when shared folders are disabled

WHile adapting to the newer kernel API we have changed the way a root
dentry is filled. At the time of mount call, we don't send any request
to the HGFS server to check if the shared folders are enabled or not.
So, irrespective of the state of the HGFS server in the VMX, the 'mount'
call succeeds. We should ideally return an error if the shared folders
are disabled.

This is done by issuing a getAttr request to the server and returning
an error if the getAttr request fails.

Signed-off-by: Dmitry Torokhov <dtor@vmware.com>

diff --git a/open-vm-tools/modules/linux/vmhgfs/filesystem.c b/open-vm-tools/modules/linux/vmhgfs/filesystem.c
index bd1d8b4ceefae3995fbb87222898dc7d2ac6bfb4..434ddd1505d62c99e9f6597730f3af2bc99855c7 100644 (file)
--- a/open-vm-tools/modules/linux/vmhgfs/filesystem.c
+++ b/open-vm-tools/modules/linux/vmhgfs/filesystem.c
@@ -83,7 +83,7 @@ HgfsOp hgfsVersionCreateSymlink;
 static inline unsigned long HgfsComputeBlockBits(unsigned long blockSize);
 static compat_kmem_cache_ctor HgfsInodeCacheCtor;
 static HgfsSuperInfo *HgfsInitSuperInfo(HgfsMountInfo *mountInfo);
-static struct dentry *HgfsGetRootDentry(struct super_block *sb);
+static int HgfsGetRootDentry(struct super_block *sb, struct dentry **rootDentry);
 static int HgfsReadSuper(struct super_block *sb,
                          void *rawData,
                          int flags);
@@ -334,7 +334,8 @@ HgfsInitSuperInfo(HgfsMountInfo *mountInfo) // IN: Passed down from the user
  *    Gets the root dentry for a given super block.
  *
  * Results:
- *    A valid root dentry on success, NULL otherwise.
+ *    zero and a valid root dentry on success
+ *    negative value on failure
  *
  * Side effects:
  *    None.
@@ -342,63 +343,78 @@ HgfsInitSuperInfo(HgfsMountInfo *mountInfo) // IN: Passed down from the user
  *----------------------------------------------------------------------------
  */
 
-static struct dentry *
-HgfsGetRootDentry(struct super_block *sb)       // IN: Super block object
+static int
+HgfsGetRootDentry(struct super_block *sb,       // IN: Super block object
+                  struct dentry **rootDentry)   // OUT: Root dentry
 {
-   struct dentry *rootDentry = NULL;
+   int result = -ENOMEM;
    struct inode *rootInode;
+   struct dentry *tempRootDentry = NULL;
+   struct HgfsAttrInfo rootDentryAttr;
+   HgfsInodeInfo *iinfo;
 
    ASSERT(sb);
+   ASSERT(rootDentry);
 
    LOG(6, (KERN_DEBUG "VMware hgfs: %s: entered\n", __func__));
 
    rootInode = HgfsGetInode(sb, HGFS_ROOT_INO);
-   if (rootInode) {
-      HgfsInodeInfo *iinfo;
-      static const HgfsAttrInfo attr = {
-         .type             = HGFS_FILE_TYPE_DIRECTORY,
-         .size             = 4192,
-         .specialPerms     = 0,
-         .ownerPerms       = HGFS_PERM_READ | HGFS_PERM_EXEC,
-         .groupPerms       = HGFS_PERM_READ | HGFS_PERM_EXEC,
-         .otherPerms       = HGFS_PERM_READ | HGFS_PERM_EXEC,
-         .mask             = HGFS_ATTR_VALID_TYPE |
-                             HGFS_ATTR_VALID_SIZE |
-                             HGFS_ATTR_VALID_SPECIAL_PERMS |
-                             HGFS_ATTR_VALID_OWNER_PERMS |
-                             HGFS_ATTR_VALID_GROUP_PERMS |
-                             HGFS_ATTR_VALID_OTHER_PERMS,
-      };
-
-      /*
-       * On an allocation failure in read_super, the inode will have been
-       * marked "bad". If it was, we certainly don't want to start playing with
-       * the HgfsInodeInfo. So quietly put the inode back and fail.
-       */
-      if (is_bad_inode(rootInode)) {
-         LOG(6, (KERN_DEBUG "VMware hgfs: %s: encountered bad inode\n",
-                 __func__));
-         iput(rootInode);
-         goto exit;
-      }
-
-      HgfsChangeFileAttributes(rootInode, &attr);
-
-      iinfo = INODE_GET_II_P(rootInode);
-      iinfo->isFakeInodeNumber = FALSE;
-      iinfo->isReferencedInode = TRUE;
+   if (rootInode == NULL) {
+      LOG(6, (KERN_DEBUG "VMware hgfs: %s: Could not get the root inode\n",
+             __func__));
+      goto exit;
    }
 
-   rootDentry = d_alloc_root(rootInode);
-   if (rootDentry == NULL) {
+   /*
+    * On an allocation failure in read_super, the inode will have been
+    * marked "bad". If it was, we certainly don't want to start playing with
+    * the HgfsInodeInfo. So quietly put the inode back and fail.
+    */
+   if (is_bad_inode(rootInode)) {
+      LOG(6, (KERN_DEBUG "VMware hgfs: %s: encountered bad inode\n",
+             __func__));
+      goto exit;
+   }
+
+   tempRootDentry = d_alloc_root(rootInode);
+   if (tempRootDentry == NULL) {
       LOG(4, (KERN_WARNING "VMware hgfs: %s: Could not get "
               "root dentry\n", __func__));
       goto exit;
    }
 
+   rootInode = NULL;
+
+   result = HgfsPrivateGetattr(tempRootDentry, &rootDentryAttr, NULL);
+   if (result) {
+      LOG(4, (KERN_WARNING "VMware hgfs: HgfsReadSuper: Could not"
+             "instantiate the root dentry\n"));
+      goto exit;
+   }
+
+   iinfo = INODE_GET_II_P(tempRootDentry->d_inode);
+   iinfo->isFakeInodeNumber = FALSE;
+   iinfo->isReferencedInode = TRUE;
+
+   if (rootDentryAttr.mask & HGFS_ATTR_VALID_FILEID) {
+      iinfo->hostFileId = rootDentryAttr.hostFileId;
+   }
+
+   HgfsChangeFileAttributes(tempRootDentry->d_inode, &rootDentryAttr);
+   HgfsDentryAgeReset(tempRootDentry);
+   tempRootDentry->d_op = &HgfsDentryOperations;
+
+   *rootDentry = tempRootDentry;
+   result = 0;
+
    LOG(6, (KERN_DEBUG "VMware hgfs: %s: finished\n", __func__));
 exit:
-   return rootDentry;
+   if (result) {
+      iput(rootInode);
+      dput(tempRootDentry);
+      *rootDentry = NULL;
+   }
+   return result;
 }
 
 
@@ -478,13 +494,13 @@ HgfsReadSuper(struct super_block *sb, // OUT: Superblock object
    sb->s_blocksize_bits = HgfsComputeBlockBits(HGFS_BLOCKSIZE);
    sb->s_blocksize = 1 << sb->s_blocksize_bits;
 
-   rootDentry = HgfsGetRootDentry(sb);
-   if (rootDentry == NULL) {
+   result = HgfsGetRootDentry(sb, &rootDentry);
+   if (result) {
       LOG(4, (KERN_WARNING "VMware hgfs: HgfsReadSuper: Could not instantiate "
               "root dentry\n"));
-      result = -ENOMEM;
       goto exit;
    }
+
    sb->s_root = rootDentry;
 
    LOG(6, (KERN_DEBUG "VMware hgfs: HgfsReadSuper: finished %s\n", si->shareName));