Using the Splunk Mobile App (for Android), when I try to share a report via Gmail (send it as attachment), in Gmail I have the following message: "Permission denied for the attachment".
Maybe it is a Gmail issue, but any suggestion to solve the problem is much appreciated.
A Google search on your error message for more appropriate sites where this issue has already been addressed reveals that it appears to be a local file access permission interfering with the GMail apps ability to obtain the attachment.
The very first discussion I found (here) seems to suggest it might be a bug in the mobile interface, in its calls to GMail. I don't know, absolutely, because I don't use the mobile app, but it appears to warrant more investigation. Raise it as a bug report, perhaps?