linux-stable.git/net/sunrpc, branch linux-4.15.y

sunrpc: remove incorrect HMAC request initialization

2018-04-19T06:55:10+00:00

commit f3aefb6a7066e24bfea7fcf1b07907576de69d63 upstream.

make_checksum_hmac_md5() is allocating an HMAC transform and doing
crypto API calls in the following order:

    crypto_ahash_init()
    crypto_ahash_setkey()
    crypto_ahash_digest()

This is wrong because it makes no sense to init() the request before a
key has been set, given that the initial state depends on the key.  And
digest() is short for init() + update() + final(), so in this case
there's no need to explicitly call init() at all.

Before commit 9fa68f620041 ("crypto: hash - prevent using keyed hashes
without setting key") the extra init() had no real effect, at least for
the software HMAC implementation.  (There are also hardware drivers that
implement HMAC-MD5, and it's not immediately obvious how gracefully they
handle init() before setkey().)  But now the crypto API detects this
incorrect initialization and returns -ENOKEY.  This is breaking NFS
mounts in some cases.

Fix it by removing the incorrect call to crypto_ahash_init().

Reported-by: Michael Young 
Fixes: 9fa68f620041 ("crypto: hash - prevent using keyed hashes without setting key")
Fixes: fffdaef2eb4a ("gss_krb5: Add support for rc4-hmac encryption")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

xprtrdma: Fix BUG after a device removal

2018-02-22T14:40:08+00:00

commit e89e8d8fcdc6751e86ccad794b052fe67e6ad619 upstream.

Michal Kalderon reports a BUG that occurs just after device removal:

[  169.112490] rpcrdma: removing device qedr0 for 192.168.110.146:20049
[  169.143909] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
[  169.181837] IP: rpcrdma_dma_unmap_regbuf+0xa/0x60 [rpcrdma]

The RPC/RDMA client transport attempts to allocate some resources
on demand. Registered buffers are one such resource. These are
allocated (or re-allocated) by xprt_rdma_allocate to hold RPC Call
and Reply messages. A hardware resource is associated with each of
these buffers, as they can be used for a Send or Receive Work
Request.

If a device is removed from under an NFS/RDMA mount, the transport
layer is responsible for releasing all hardware resources before
the device can be finally unplugged. A BUG results when the NFS
mount hasn't yet seen much activity: the transport tries to release
resources that haven't yet been allocated.

rpcrdma_free_regbuf() already checks for this case, so just move
that check to cover the DEVICE_REMOVAL case as well.

Reported-by: Michal Kalderon 
Fixes: bebd031866ca ("xprtrdma: Support unplugging an HCA ...")
Signed-off-by: Chuck Lever 
Tested-by: Michal Kalderon 
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Anna Schumaker 
Signed-off-by: Greg Kroah-Hartman

xprtrdma: Fix calculation of ri_max_send_sges

2018-02-22T14:40:08+00:00

commit 1179e2c27efe21167ec9d882b14becefba2ee990 upstream.

Commit 16f906d66cd7 ("xprtrdma: Reduce required number of send
SGEs") introduced the rpcrdma_ia::ri_max_send_sges field. This fixes
a problem where xprtrdma would not work if the device's max_sge
capability was small (low single digits).

At least RPCRDMA_MIN_SEND_SGES are needed for the inline parts of
each RPC. ri_max_send_sges is set to this value:

  ia->ri_max_send_sges = max_sge - RPCRDMA_MIN_SEND_SGES;

Then when marshaling each RPC, rpcrdma_args_inline uses that value
to determine whether the device has enough Send SGEs to convey an
NFS WRITE payload inline, or whether instead a Read chunk is
required.

More recently, commit ae72950abf99 ("xprtrdma: Add data structure to
manage RDMA Send arguments") used the ri_max_send_sges value to
calculate the size of an array, but that commit erroneously assumed
ri_max_send_sges contains a value similar to the device's max_sge,
and not one that was reduced by the minimum SGE count.

This assumption results in the calculated size of the sendctx's
Send SGE array to be too small. When the array is used to marshal
an RPC, the code can write Send SGEs into the following sendctx
element in that array, corrupting it. When the device's max_sge is
large, this issue is entirely harmless; but it results in an oops
in the provider's post_send method, if dev.attrs.max_sge is small.

So let's straighten this out: ri_max_send_sges will now contain a
value with the same meaning as dev.attrs.max_sge, which makes
the code easier to understand, and enables rpcrdma_sendctx_create
to calculate the size of the SGE array correctly.

Reported-by: Michal Kalderon 
Fixes: 16f906d66cd7 ("xprtrdma: Reduce required number of send SGEs")
Signed-off-by: Chuck Lever 
Tested-by: Michal Kalderon 
Cc: stable@vger.kernel.org # v4.10+
Signed-off-by: Anna Schumaker 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'nfs-for-4.15-3' of git://git.linux-nfs.org/projects/anna/linux-nfs

2017-12-16T21:12:53+00:00

Pull NFS client fixes from Anna Schumaker:
 "This has two stable bugfixes, one to fix a BUG_ON() when
  nfs_commit_inode() is called with no outstanding commit requests and
  another to fix a race in the SUNRPC receive codepath.

  Additionally, there are also fixes for an NFS client deadlock and an
  xprtrdma performance regression.

  Summary:

  Stable bugfixes:
   - NFS: Avoid a BUG_ON() in nfs_commit_inode() by not waiting for a
     commit in the case that there were no commit requests.
   - SUNRPC: Fix a race in the receive code path

  Other fixes:
   - NFS: Fix a deadlock in nfs client initialization
   - xprtrdma: Fix a performance regression for small IOs"

* tag 'nfs-for-4.15-3' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  SUNRPC: Fix a race in the receive code path
  nfs: don't wait on commit in nfs_commit_inode() if there were no commit requests
  xprtrdma: Spread reply processing over more CPUs
  nfs: fix a deadlock in nfs client initialization

SUNRPC: Fix a race in the receive code path

2017-12-15T19:31:56+00:00

We must ensure that the call to rpc_sleep_on() in xprt_transmit() cannot
race with the call to xprt_complete_rqst().

Reported-by: Chuck Lever 
Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=317
Fixes: ce7c252a8c74 ("SUNRPC: Add a separate spinlock to protect..")
Cc: stable@vger.kernel.org # 4.14+
Reviewed-by: Chuck Lever 
Signed-off-by: Trond Myklebust 
Signed-off-by: Anna Schumaker

xprtrdma: Spread reply processing over more CPUs

2017-12-15T19:31:50+00:00

Commit d8f532d20ee4 ("xprtrdma: Invoke rpcrdma_reply_handler
directly from RECV completion") introduced a performance regression
for NFS I/O small enough to not need memory registration. In multi-
threaded benchmarks that generate primarily small I/O requests,
IOPS throughput is reduced by nearly a third. This patch restores
the previous level of throughput.

Because workqueues are typically BOUND (in particular ib_comp_wq,
nfsiod_workqueue, and rpciod_workqueue), NFS/RDMA workloads tend
to aggregate on the CPU that is handling Receive completions.

The usual approach to addressing this problem is to create a QP
and CQ for each CPU, and then schedule transactions on the QP
for the CPU where you want the transaction to complete. The
transaction then does not require an extra context switch during
completion to end up on the same CPU where the transaction was
started.

This approach doesn't work for the Linux NFS/RDMA client because
currently the Linux NFS client does not support multiple connections
per client-server pair, and the RDMA core API does not make it
straightforward for ULPs to determine which CPU is responsible for
handling Receive completions for a CQ.

So for the moment, record the CPU number in the rpcrdma_req before
the transport sends each RPC Call. Then during Receive completion,
queue the RPC completion on that same CPU.

Additionally, move all RPC completion processing to the deferred
handler so that even RPCs with simple small replies complete on
the CPU that sent the corresponding RPC Call.

Fixes: d8f532d20ee4 ("xprtrdma: Invoke rpcrdma_reply_handler ...")
Signed-off-by: Chuck Lever 
Signed-off-by: Anna Schumaker

kernel: make groups_sort calling a responsibility group_info allocators

2017-12-15T00:00:49+00:00

In testing, we found that nfsd threads may call set_groups in parallel
for the same entry cached in auth.unix.gid, racing in the call of
groups_sort, corrupting the groups for that entry and leading to
permission denials for the client.

This patch:
 - Make groups_sort globally visible.
 - Move the call to groups_sort to the modifiers of group_info
 - Remove the call to groups_sort from set_groups

Link: http://lkml.kernel.org/r/20171211151420.18655-1-thiago.becker@gmail.com
Signed-off-by: Thiago Rafael Becker 
Reviewed-by: Matthew Wilcox 
Reviewed-by: NeilBrown 
Acked-by: "J. Bruce Fields" 
Cc: Al Viro 
Cc: Martin Schwidefsky 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'nfs-for-4.15-2' of git://git.linux-nfs.org/projects/anna/linux-nfs

2017-12-02T01:04:20+00:00

Pull NFS client fixes from Anna Schumaker:
 "These patches fix a problem with compiling using an old version of
  gcc, and also fix up error handling in the SUNRPC layer.

   - NFSv4: Ensure gcc 4.4.4 can compile initialiser for
     "invalid_stateid"

   - SUNRPC: Allow connect to return EHOSTUNREACH

   - SUNRPC: Handle ENETDOWN errors"

* tag 'nfs-for-4.15-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  SUNRPC: Handle ENETDOWN errors
  SUNRPC: Allow connect to return EHOSTUNREACH
  NFSv4: Ensure gcc 4.4.4 can compile initialiser for "invalid_stateid"

SUNRPC: Handle ENETDOWN errors

2017-11-30T16:52:52+00:00

Signed-off-by: Trond Myklebust 
Signed-off-by: Anna Schumaker

SUNRPC: Allow connect to return EHOSTUNREACH

2017-11-29T19:02:01+00:00

Reported-by: Dmitry Vyukov 
Signed-off-by: Trond Myklebust 
Tested-by: Dmitry Vyukov 
Signed-off-by: Anna Schumaker