abc02e5602
I noticed LAYOUTGET(LAYOUTIOMODE4_RW) returning NFS4ERR_ACCESS unexpectedly. The NFS client had created a file with mode 0444, and the server had returned a write delegation on the OPEN(CREATE). The client was requesting a RW layout using the write delegation stateid so that it could flush file modifications. Creating a read-only file does not seem to be problematic for NFSv4.1 without pNFS, so I began looking at NFSD's implementation of LAYOUTGET. The failure was because fh_verify() was doing a permission check as part of verifying the FH presented during the LAYOUTGET. It uses the loga_iomode value to specify the @accmode argument to fh_verify(). fh_verify(MAY_WRITE) on a file whose mode is 0444 fails with -EACCES. To permit LAYOUT* operations in this case, add OWNER_OVERRIDE when checking the access permission of the incoming file handle for LAYOUTGET and LAYOUTCOMMIT. Cc: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org # v6.6+ Message-Id: 4E9C0D74-A06D-4DC3-A48A-73034DC40395@oracle.com Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.