[ Upstream commit 986a4b63d3bc5f2c0eb4083b05aff2bf883b7b2f ]

Braino when converting "buf->len -=" to "buf->len = len -".

The result is under-estimation of the ralign and rslack values. On
krb5p mounts, this has caused READDIR to fail with EIO, and KASAN
splats when decoding READLINK replies.

As a result of fixing this oversight, the gss_unwrap method now
returns a buf->len that can be shorter than priv_len for small
RPC messages. The additional adjustment done in unwrap_priv_data()
can underflow buf->len. This causes the nfsd_request_too_large
check to fail during some NFSv3 operations.

Reported-by: Marian Rainer-Harbach
Reported-by: Pierre Sauter <pierre.sauter@stwm.de>
BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1886277
Fixes: 31c9590ae468 ("SUNRPC: Add "@len" parameter to gss_unwrap()")
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit e814eecbe3bbeaa8b004d25a4b8974d232b765a9 ]

Commit 07d0ff3b0cd2 ("svcrdma: Clean up Read chunk path") moved the
page saver logic so that it gets executed event when an error occurs.
In that case, the I/O is never posted, and those pages are then
leaked. Errors in this path, however, are quite rare.

Fixes: 07d0ff3b0cd2 ("svcrdma: Clean up Read chunk path")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Currently the header size calculations are using an assignment
operator instead of a += operator when accumulating the header
size leading to incorrect sizes.  Fix this by using the correct
operator.

Addresses-Coverity: ("Unused value")
Fixes: 302d3deb2068 ("xprtrdma: Prevent inline overflow")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Ensure that the connect worker is awoken if an attempt to establish
a connection is unsuccessful. Otherwise the worker waits forever
and the transport workload hangs.

Connect errors should not attempt to destroy the ep, since the
connect worker continues to use it after the handler runs, so these
errors are now handled independently of DISCONNECTED events.

Reported-by: Dan Aloni <dan@kernelim.com>
Fixes: e28ce90083f0 ("xprtrdma: kmalloc rpcrdma_ep separate from rpcrdma_xprt")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

I noticed that when rpcrdma_xprt_connect() returns -ENOMEM,
instead of retrying the connect, the RPC client kills the
RPC task that requested the connection. We want a retry
here.

Fixes: cb586decbb88 ("xprtrdma: Make sendctx queue lifetime the same as connection lifetime")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Both Dan and I have observed two processes invoking
rpcrdma_xprt_disconnect() concurrently. In my case:

1. The connect worker invokes rpcrdma_xprt_disconnect(), which
   drains the QP and waits for the final completion
2. This causes the newly posted Receive to flush and invoke
   xprt_force_disconnect()
3. xprt_force_disconnect() sets CLOSE_WAIT and wakes up the RPC task
   that is holding the transport lock
4. The RPC task invokes xprt_connect(), which calls ->ops->close
5. xprt_rdma_close() invokes rpcrdma_xprt_disconnect(), which tries
   to destroy the QP.

Deadlock.

To prevent xprt_force_disconnect() from waking anything, handle the
clean up after a failed connection attempt in the xprt's sndtask.

The retry loop is removed from rpcrdma_xprt_connect() to ensure
that the newly allocated ep and id are properly released before
a REJECTED connection attempt can be retried.

Reported-by: Dan Aloni <dan@kernelim.com>
Fixes: e28ce90083f0 ("xprtrdma: kmalloc rpcrdma_ep separate from rpcrdma_xprt")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

In the error paths, there's no need to call kfree(ep) after calling
rpcrdma_ep_put(ep).

Fixes: e28ce90083f0 ("xprtrdma: kmalloc rpcrdma_ep separate from rpcrdma_xprt")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Pull nfsd fixes from Bruce Fields:
 "Fixes for a umask bug on exported filesystems lacking ACL support, a
  leak and a module unloading bug in the /proc/fs/nfsd/clients/ code,
  and a compile warning"

* tag 'nfsd-5.8-1' of git://linux-nfs.org/~bfields/linux:
  SUNRPC: Add missing definition of ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
  nfsd: fix nfsdfs inode reference count leak
  nfsd4: fix nfsdfs reference count loop
  nfsd: apply umask on fs without ACL support

Even if that's only a warning, not including asm/cacheflush.h
leads to svc_flush_bvec() being empty allthough powerpc defines
ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE.

  CC      net/sunrpc/svcsock.o
net/sunrpc/svcsock.c:227:5: warning: "ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE" is not defined [-Wundef]
 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
     ^

Include linux/highmem.h so that asm/cacheflush.h will be included.

Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reported-by: kernel test robot <lkp@intel.com>
Fixes: ca07eda33e01 ("SUNRPC: Refactor svc_recvfrom()")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

@subbuf is an output parameter of xdr_buf_subsegment(). A survey of
call sites shows that @subbuf is always uninitialized before
xdr_buf_segment() is invoked by callers.

There are some execution paths through xdr_buf_subsegment() that do
not set all of the fields in @subbuf, leaving some pointer fields
containing garbage addresses. Subsequent processing of that buffer
then results in a page fault.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>