linux-stable.git/net/sunrpc, branch linux-3.17.y

sunrpc: fix sleeping under rcu_read_lock in gss_stringify_acceptor

2014-11-21T17:23:13+00:00

commit b3ecba096729f521312d1863ad22530695527aed upstream.

Bruce reported that he was seeing the following BUG pop:

    BUG: sleeping function called from invalid context at mm/slab.c:2846
    in_atomic(): 0, irqs_disabled(): 0, pid: 4539, name: mount.nfs
    2 locks held by mount.nfs/4539:
    #0:  (nfs_clid_init_mutex){+.+.+.}, at: [] nfs4_discover_server_trunking+0x4a/0x2f0 [nfsv4]
    #1:  (rcu_read_lock){......}, at: [] gss_stringify_acceptor+0x5/0xb0 [auth_rpcgss]
    Preemption disabled at:[] printk+0x4d/0x4f

    CPU: 3 PID: 4539 Comm: mount.nfs Not tainted 3.18.0-rc1-00013-g5b095e9 #3393
    Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
    ffff880021499390 ffff8800381476a8 ffffffff81a534cf 0000000000000001
    0000000000000000 ffff8800381476c8 ffffffff81097854 00000000000000d0
    0000000000000018 ffff880038147718 ffffffff8118e4f3 0000000020479f00
    Call Trace:
    [] dump_stack+0x4f/0x7c
    [] __might_sleep+0x114/0x180
    [] __kmalloc+0x1a3/0x280
    [] gss_stringify_acceptor+0x58/0xb0 [auth_rpcgss]
    [] ? gss_stringify_acceptor+0x5/0xb0 [auth_rpcgss]
    [] rpcauth_stringify_acceptor+0x18/0x30 [sunrpc]
    [] nfs4_proc_setclientid+0x199/0x380 [nfsv4]
    [] ? nfs4_proc_setclientid+0x200/0x380 [nfsv4]
    [] nfs40_discover_server_trunking+0xda/0x150 [nfsv4]
    [] ? nfs40_discover_server_trunking+0x5/0x150 [nfsv4]
    [] nfs4_discover_server_trunking+0x7f/0x2f0 [nfsv4]
    [] nfs4_init_client+0x104/0x2f0 [nfsv4]
    [] nfs_get_client+0x314/0x3f0 [nfs]
    [] ? nfs_get_client+0xe0/0x3f0 [nfs]
    [] nfs4_set_client+0x8a/0x110 [nfsv4]
    [] ? __rpc_init_priority_wait_queue+0xa8/0xf0 [sunrpc]
    [] nfs4_create_server+0x12f/0x390 [nfsv4]
    [] nfs4_remote_mount+0x32/0x60 [nfsv4]
    [] mount_fs+0x39/0x1b0
    [] ? __alloc_percpu+0x15/0x20
    [] vfs_kern_mount+0x6b/0x150
    [] nfs_do_root_mount+0x86/0xc0 [nfsv4]
    [] nfs4_try_mount+0x44/0xc0 [nfsv4]
    [] ? get_nfs_version+0x27/0x90 [nfs]
    [] nfs_fs_mount+0x47d/0xd60 [nfs]
    [] ? mutex_unlock+0xe/0x10
    [] ? nfs_remount+0x430/0x430 [nfs]
    [] ? nfs_clone_super+0x140/0x140 [nfs]
    [] mount_fs+0x39/0x1b0
    [] ? __alloc_percpu+0x15/0x20
    [] vfs_kern_mount+0x6b/0x150
    [] do_mount+0x210/0xbe0
    [] ? copy_mount_options+0x3a/0x160
    [] SyS_mount+0x6f/0xb0
    [] system_call_fastpath+0x12/0x17

Sleeping under the rcu_read_lock is bad. This patch fixes it by dropping
the rcu_read_lock before doing the allocation and then reacquiring it
and redoing the dereference before doing the copy. If we find that the
string has somehow grown in the meantime, we'll reallocate and try again.

Reported-by: "J. Bruce Fields" 
Signed-off-by: Jeff Layton 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

SUNRPC: Add missing support for RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT

2014-11-14T18:10:22+00:00

commit 2aca5b869ace67a63aab895659e5dc14c33a4d6e upstream.

The flag RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT was intended introduced in
order to allow NFSv4 clients to disable resend timeouts. Since those
cause the RPC layer to break the connection, they mess up the duplicate
reply caches that remain indexed on the port number in NFSv4..

This patch includes the code that was missing in the original to
set the appropriate flag in struct rpc_clnt, when the caller of
rpc_create() sets RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT.

Fixes: 8a19a0b6cb2e (SUNRPC: Add RPC task and client level options to...)
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

SUNRPC: Don't wake tasks during connection abort

2014-11-14T18:10:22+00:00

commit a743419f420a64d442280845c0377a915b76644f upstream.

When aborting a connection to preserve source ports, don't wake the task in
xs_error_report.  This allows tasks with RPC_TASK_SOFTCONN to succeed if the
connection needs to be re-established since it preserves the task's status
instead of setting it to the status of the aborting kernel_connect().

This may also avoid a potential conflict on the socket's lock.

Signed-off-by: Benjamin Coddington 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2014-08-14T00:13:19+00:00

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

   - stable fix for a bug in nfs3_list_one_acl()
   - speed up NFS path walks by supporting LOOKUP_RCU
   - more read/write code cleanups
   - pNFS fixes for layout return on close
   - fixes for the RCU handling in the rpcsec_gss code
   - more NFS/RDMA fixes"

* tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
  nfs: reject changes to resvport and sharecache during remount
  NFS: Avoid infinite loop when RELEASE_LOCKOWNER getting expired error
  SUNRPC: remove all refcounting of groupinfo from rpcauth_lookupcred
  NFS: fix two problems in lookup_revalidate in RCU-walk
  NFS: allow lockless access to access_cache
  NFS: teach nfs_lookup_verify_inode to handle LOOKUP_RCU
  NFS: teach nfs_neg_need_reval to understand LOOKUP_RCU
  NFS: support RCU_WALK in nfs_permission()
  sunrpc/auth: allow lockless (rcu) lookup of credential cache.
  NFS: prepare for RCU-walk support but pushing tests later in code.
  NFS: nfs4_lookup_revalidate: only evaluate parent if it will be used.
  NFS: add checks for returned value of try_module_get()
  nfs: clear_request_commit while holding i_lock
  pnfs: add pnfs_put_lseg_async
  pnfs: find swapped pages on pnfs commit lists too
  nfs: fix comment and add warn_on for PG_INODE_REF
  nfs: check wait_on_bit_lock err in page_group_lock
  sunrpc: remove "ec" argument from encrypt_v2 operation
  sunrpc: clean up sparse endianness warnings in gss_krb5_wrap.c
  sunrpc: clean up sparse endianness warnings in gss_krb5_seal.c
  ...

Merge branch 'for-3.17' of git://linux-nfs.org/~bfields/linux

2014-08-09T21:31:18+00:00

Pull nfsd updates from Bruce Fields:
 "This includes a major rewrite of the NFSv4 state code, which has
  always depended on a single mutex.  As an example, open creates are no
  longer serialized, fixing a performance regression on NFSv3->NFSv4
  upgrades.  Thanks to Jeff, Trond, and Benny, and to Christoph for
  review.

  Also some RDMA fixes from Chuck Lever and Steve Wise, and
  miscellaneous fixes from Kinglong Mee and others"

* 'for-3.17' of git://linux-nfs.org/~bfields/linux: (167 commits)
  svcrdma: remove rdma_create_qp() failure recovery logic
  nfsd: add some comments to the nfsd4 object definitions
  nfsd: remove the client_mutex and the nfs4_lock/unlock_state wrappers
  nfsd: remove nfs4_lock_state: nfs4_state_shutdown_net
  nfsd: remove nfs4_lock_state: nfs4_laundromat
  nfsd: Remove nfs4_lock_state(): reclaim_complete()
  nfsd: Remove nfs4_lock_state(): setclientid, setclientid_confirm, renew
  nfsd: Remove nfs4_lock_state(): exchange_id, create/destroy_session()
  nfsd: Remove nfs4_lock_state(): nfsd4_open and nfsd4_open_confirm
  nfsd: Remove nfs4_lock_state(): nfsd4_delegreturn()
  nfsd: Remove nfs4_lock_state(): nfsd4_open_downgrade + nfsd4_close
  nfsd: Remove nfs4_lock_state(): nfsd4_lock/locku/lockt()
  nfsd: Remove nfs4_lock_state(): nfsd4_release_lockowner
  nfsd: Remove nfs4_lock_state(): nfsd4_test_stateid/nfsd4_free_stateid
  nfsd: Remove nfs4_lock_state(): nfs4_preprocess_stateid_op()
  nfsd: remove old fault injection infrastructure
  nfsd: add more granular locking to *_delegations fault injectors
  nfsd: add more granular locking to forget_openowners fault injector
  nfsd: add more granular locking to forget_locks fault injector
  nfsd: add a list_head arg to nfsd_foreach_client_lock
  ...

svcrdma: remove rdma_create_qp() failure recovery logic

2014-08-05T20:09:21+00:00

In svc_rdma_accept(), if rdma_create_qp() fails, there is useless
logic to try and call rdma_create_qp() again with reduced sge depths.
The assumption, I guess, was that perhaps the initial sge depths
chosen were too big.  However they initial depths are selected based
on the rdma device attribute max_sge returned from ib_query_device().
If rdma_create_qp() fails, it would not be because the max_send_sge and
max_recv_sge values passed in exceed the device's max.  So just remove
this code.

Signed-off-by: Steve Wise 
Signed-off-by: J. Bruce Fields

SUNRPC: remove all refcounting of groupinfo from rpcauth_lookupcred

2014-08-04T13:22:08+00:00

current_cred() can only be changed by 'current', and
cred->group_info is never changed.  If a new group_info is
needed, a new 'cred' is created.

Consequently it is always safe to access
   current_cred()->group_info

without taking any further references.
So drop the refcounting and the incorrect rcu_dereference().

Signed-off-by: NeilBrown 
Signed-off-by: Trond Myklebust

sunrpc/auth: allow lockless (rcu) lookup of credential cache.

2014-08-03T21:14:12+00:00

The new flag RPCAUTH_LOOKUP_RCU to credential lookup avoids locking,
does not take a reference on the returned credential, and returns
-ECHILD if a simple lookup was not possible.

The returned value can only be used within an rcu_read_lock protected
region.

The main user of this is the new rpc_lookup_cred_nonblock() which
returns a pointer to the current credential which is only rcu-safe (no
ref-count held), and might return -ECHILD if allocation was required.

Signed-off-by: NeilBrown 
Signed-off-by: Trond Myklebust

sunrpc: remove "ec" argument from encrypt_v2 operation

2014-08-03T21:05:24+00:00

It's always 0.

Signed-off-by: Jeff Layton 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Trond Myklebust

sunrpc: clean up sparse endianness warnings in gss_krb5_wrap.c

2014-08-03T21:05:24+00:00

Fix the endianness handling in gss_wrap_kerberos_v1 and drop the memset
call there in favor of setting the filler bytes directly.

In gss_wrap_kerberos_v2, get rid of the "ec" variable which is always
zero, and drop the endianness conversion of 0. Sparse handles 0 as a
special case, so it's not necessary.

Signed-off-by: Jeff Layton 
Signed-off-by: Trond Myklebust