1 files changed, 49 insertions, 0 deletions

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index eb24653612bc..7ae03283bd61 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -3485,6 +3485,44 @@ cifs_get_volume_info(char *mount_data, const char *devname)
         return volume_info;
 }
 
+static int
+cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
+                                        unsigned int xid,
+                                        struct cifs_tcon *tcon,
+                                        struct cifs_sb_info *cifs_sb,
+                                        char *full_path)
+{
+        int rc;
+        char *s;
+        char sep, tmp;
+
+        sep = CIFS_DIR_SEP(cifs_sb);
+        s = full_path;
+
+        rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
+        while (rc == 0) {
+                /* skip separators */
+                while (*s == sep)
+                        s++;
+                if (!*s)
+                        break;
+                /* next separator */
+                while (*s && *s != sep)
+                        s++;
+
+                /*
+                 * temporarily null-terminate the path at the end of
+                 * the current component
+                 */
+                tmp = *s;
+                *s = 0;
+                rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
+                                                     full_path);
+                *s = tmp;
+        }
+        return rc;
+}
+
 int
 cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *volume_info)
 {
@@ -3622,6 +3660,16 @@ remote_path_check:
                         kfree(full_path);
                         goto mount_fail_check;
                 }
+
+                rc = cifs_are_all_path_components_accessible(server,
+                                                             xid, tcon, cifs_sb,
+                                                             full_path);
+                if (rc != 0) {
+                        cifs_dbg(VFS, "cannot query dirs between root and final path, "
+                                 "enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
+                        cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
+                        rc = 0;
+                }
                 kfree(full_path);
         }
 
@@ -3891,6 +3939,7 @@ cifs_umount(struct cifs_sb_info *cifs_sb)
 
         bdi_destroy(&cifs_sb->bdi);
         kfree(cifs_sb->mountdata);
+        kfree(cifs_sb->prepath);
         call_rcu(&cifs_sb->rcu, delayed_free);
 }