Re: [PATCH 1/1] Fix permission checking by NFS client for open-create with mode 000

From: J. Bruce Fields
Date: Fri Jul 11 2014 - 16:20:50 EST

On Wed, Jul 09, 2014 at 07:12:09PM -0400, Trond Myklebust wrote:
> Oops. Sorry, the correct sub-sub-sub-sub-....paragraph is this one:
> Permission to execute a file.
> Servers SHOULD allow a user the ability to read the data of the
> file when only the ACE4_EXECUTE access mask bit is allowed.
> This is because there is no way to execute a file without
> reading the contents. Though a server may treat ACE4_EXECUTE
> and ACE4_READ_DATA bits identically when deciding to permit a
> READ operation, it SHOULD still allow the two bits to be set
> independently in ACLs, and MUST distinguish between them when
> replying to ACCESS operations. In particular, servers SHOULD
> NOT silently turn on one of the two bits when the other is set,
> as that would make it impossible for the client to correctly
> enforce the distinction between read and execute permissions.
> > To me that translates as saying that the server SHOULD accept an
> > situation.
> Same conclusion, though....

Are we sure that's not just a spec bug?

Allowing OPEN(BOTH) on a -wx file seems like a pretty weird result.

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