There are some user-space based NFS clients (e.g. NFS Client library). Can I bypass file permissions by using such client?
Server1 has nfs-exported file system with files
-rwxr-xr-x user1 file1 -rwx------ user2 file2
Client1 uses usual NFS client (kernel-mode based) and user1@client1 can read only
file1, but not
As I understand, client1 sends uid in nfs request, server1 do a permissions check based on the request data. So, I suggest this is possible to have a client2:
Client2 uses user-space client, and hacker@client2 knows uids of user1 and user2; If he wants to read
file1 he can send uid of user1; if he wants to read file2, he sends uid of user2.
Is the scheme possible?