7be8c165dc
commit 5866efa8cbfbadf3905072798e96652faf02dbe8 upstream.
gss_read_proxy_verf() assumes things about the XDR buffer containing
the RPC Call that are not true for buffers generated by
svc_rdma_recv().
RDMA's buffers look more like what the upper layer generates for
sending: head is a kmalloc'd buffer; it does not point to a page
whose contents are contiguous with the first page in the buffers'
page array. The result is that ACCEPT_SEC_CONTEXT via RPC/RDMA has
stopped working on Linux NFS servers that use gssproxy.
This does not affect clients that use only TCP to send their
ACCEPT_SEC_CONTEXT operation (that's all Linux clients). Other
clients, like Solaris NFS clients, send ACCEPT_SEC_CONTEXT on the
same transport as they send all other NFS operations. Such clients
can send ACCEPT_SEC_CONTEXT via RPC/RDMA.
I thought I had found every direct reference in the server RPC code
to the rqstp->rq_pages field.
Bug found at the 2019 Westford NFS bake-a-thon.
Fixes: 3316f0631139 ("svcrdma: Persistently allocate and DMA- ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Bill Baker <bill.baker@oracle.com>
Reviewed-by: Simo Sorce <simo@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 Restructured Text 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.