Commit Graph

3770 Commits

Author SHA1 Message Date
J. Bruce Fields 8dfd785ae1 rpc: fix gss_svc_init cleanup on failure
[ Upstream commit 5a4753446253a427c0ff1e433b9c4933e5af207c ]

The failure case here should be rare, but it's obviously wrong.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22 12:26:33 +02:00
Trond Myklebust 9ee7b45edd SUNRPC: Fix potential memory corruption
[ Upstream commit c2dc3e5fad13aca5d7bdf4bcb52b1a1d707c8555 ]

We really should not call rpc_wake_up_queued_task_set_status() with
xprt->snd_task as an argument unless we are certain that is actually an
rpc_task.

Fixes: 0445f92c5d ("SUNRPC: Fix disconnection races")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22 12:26:24 +02:00
Zhang Xiaoxu f9c7f26879 SUNRPC: Should wake up the privileged task firstly.
commit 5483b904bf336948826594610af4c9bbb0d9e3aa upstream.

When find a task from wait queue to wake up, a non-privileged task may
be found out, rather than the privileged. This maybe lead a deadlock
same as commit dfe1fe75e00e ("NFSv4: Fix deadlock between nfs4_evict_inode()
and nfs4_opendata_get_inode()"):

Privileged delegreturn task is queued to privileged list because all
the slots are assigned. If there has no enough slot to wake up the
non-privileged batch tasks(session less than 8 slot), then the privileged
delegreturn task maybe lost waked up because the found out task can't
get slot since the session is on draining.

So we should treate the privileged task as the emergency task, and
execute it as for as we can.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 5fcdfacc01 ("NFSv4: Return delegations synchronously in evict_inode")
Cc: stable@vger.kernel.org
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14 16:53:05 +02:00
Zhang Xiaoxu d060386ffd SUNRPC: Fix the batch tasks count wraparound.
commit fcb170a9d825d7db4a3fb870b0300f5a40a8d096 upstream.

The 'queue->nr' will wraparound from 0 to 255 when only current
priority queue has tasks. This maybe lead a deadlock same as commit
dfe1fe75e00e ("NFSv4: Fix deadlock between nfs4_evict_inode()
and nfs4_opendata_get_inode()"):

Privileged delegreturn task is queued to privileged list because all
the slots are assigned. When non-privileged task complete and release
the slot, a non-privileged maybe picked out. It maybe allocate slot
failed when the session on draining.

If the 'queue->nr' has wraparound to 255, and no enough slot to
service it, then the privileged delegreturn will lost to wake up.

So we should avoid the wraparound on 'queue->nr'.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 5fcdfacc01 ("NFSv4: Return delegations synchronously in evict_inode")
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14 16:53:05 +02:00
Baptiste Lepers a04c2a398d sunrpc: Fix misplaced barrier in call_decode
[ Upstream commit f8f7e0fb22b2e75be55f2f0c13e229e75b0eac07 ]

Fix a misplaced barrier in call_decode. The struct rpc_rqst is modified
as follows by xprt_complete_rqst:

req->rq_private_buf.len = copied;
/* Ensure all writes are done before we update */
/* req->rq_reply_bytes_recvd */
smp_wmb();
req->rq_reply_bytes_recvd = copied;

And currently read as follows by call_decode:

smp_rmb(); // misplaced
if (!req->rq_reply_bytes_recvd)
   goto out;
req->rq_rcv_buf.len = req->rq_private_buf.len;

This patch places the smp_rmb after the if to ensure that
rq_reply_bytes_recvd and rq_private_buf.len are read in order.

Fixes: 9ba828861c ("SUNRPC: Don't try to parse incomplete RPC messages")
Signed-off-by: Baptiste Lepers <baptiste.lepers@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19 10:08:27 +02:00
J. Bruce Fields c899b8391a rpc: fix NULL dereference on kmalloc failure
[ Upstream commit 0ddc942394013f08992fc379ca04cffacbbe3dae ]

I think this is unlikely but possible:

svc_authenticate sets rq_authop and calls svcauth_gss_accept.  The
kmalloc(sizeof(*svcdata), GFP_KERNEL) fails, leaving rq_auth_data NULL,
and returning SVC_DENIED.

This causes svc_process_common to go to err_bad_auth, and eventually
call svc_authorise.  That calls ->release == svcauth_gss_release, which
tries to dereference rq_auth_data.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Link: https://lore.kernel.org/linux-nfs/3F1B347F-B809-478F-A1E9-0BE98E22B0F0@oracle.com/T/#t
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-07 14:47:38 +02:00
Daniel Kobras f0b09d5477 sunrpc: fix refcount leak for rpc auth modules
commit f1442d6349a2e7bb7a6134791bdc26cb776c79af upstream.

If an auth module's accept op returns SVC_CLOSE, svc_process_common()
enters a call path that does not call svc_authorise() before leaving the
function, and thus leaks a reference on the auth module's refcount. Hence,
make sure calls to svc_authenticate() and svc_authorise() are paired for
all call paths, to make sure rpc auth modules can be unloaded.

Signed-off-by: Daniel Kobras <kobras@puzzle-itc.de>
Fixes: 4d712ef1db ("svcauth_gss: Close connection when dropping an incoming message")
Link: https://lore.kernel.org/linux-nfs/3F1B347F-B809-478F-A1E9-0BE98E22B0F0@oracle.com/T/#t
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-24 11:26:39 +01:00
Timo Rothenpieler b439aac773 svcrdma: disable timeouts on rdma backchannel
commit 6820bf77864d5894ff67b5c00d7dba8f92011e3d upstream.

This brings it in line with the regular tcp backchannel, which also has
all those timeouts disabled.

Prevents the backchannel from timing out, getting some async operations
like server side copying getting stuck indefinitely on the client side.

Signed-off-by: Timo Rothenpieler <timo@rothenpieler.org>
Fixes: 5d252f90a8 ("svcrdma: Add class for RDMA backwards direction transport")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-24 11:26:38 +01:00
Joe Korty d1ae8f16c2 NFSD: Repair misuse of sv_lock in 5.10.16-rt30.
commit c7de87ff9dac5f396f62d584f3908f80ddc0e07b upstream.

[ This problem is in mainline, but only rt has the chops to be
able to detect it. ]

Lockdep reports a circular lock dependency between serv->sv_lock and
softirq_ctl.lock on system shutdown, when using a kernel built with
CONFIG_PREEMPT_RT=y, and a nfs mount exists.

This is due to the definition of spin_lock_bh on rt:

	local_bh_disable();
	rt_spin_lock(lock);

which forces a softirq_ctl.lock -> serv->sv_lock dependency.  This is
not a problem as long as _every_ lock of serv->sv_lock is a:

	spin_lock_bh(&serv->sv_lock);

but there is one of the form:

	spin_lock(&serv->sv_lock);

This is what is causing the circular dependency splat.  The spin_lock()
grabs the lock without first grabbing softirq_ctl.lock via local_bh_disable.
If later on in the critical region,  someone does a local_bh_disable, we
get a serv->sv_lock -> softirq_ctrl.lock dependency established.  Deadlock.

Fix is to make serv->sv_lock be locked with spin_lock_bh everywhere, no
exceptions.

[  OK  ] Stopped target NFS client services.
         Stopping Logout off all iSCSI sessions on shutdown...
         Stopping NFS server and services...
[  109.442380]
[  109.442385] ======================================================
[  109.442386] WARNING: possible circular locking dependency detected
[  109.442387] 5.10.16-rt30 #1 Not tainted
[  109.442389] ------------------------------------------------------
[  109.442390] nfsd/1032 is trying to acquire lock:
[  109.442392] ffff994237617f60 ((softirq_ctrl.lock).lock){+.+.}-{2:2}, at: __local_bh_disable_ip+0xd9/0x270
[  109.442405]
[  109.442405] but task is already holding lock:
[  109.442406] ffff994245cb00b0 (&serv->sv_lock){+.+.}-{0:0}, at: svc_close_list+0x1f/0x90
[  109.442415]
[  109.442415] which lock already depends on the new lock.
[  109.442415]
[  109.442416]
[  109.442416] the existing dependency chain (in reverse order) is:
[  109.442417]
[  109.442417] -> #1 (&serv->sv_lock){+.+.}-{0:0}:
[  109.442421]        rt_spin_lock+0x2b/0xc0
[  109.442428]        svc_add_new_perm_xprt+0x42/0xa0
[  109.442430]        svc_addsock+0x135/0x220
[  109.442434]        write_ports+0x4b3/0x620
[  109.442438]        nfsctl_transaction_write+0x45/0x80
[  109.442440]        vfs_write+0xff/0x420
[  109.442444]        ksys_write+0x4f/0xc0
[  109.442446]        do_syscall_64+0x33/0x40
[  109.442450]        entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  109.442454]
[  109.442454] -> #0 ((softirq_ctrl.lock).lock){+.+.}-{2:2}:
[  109.442457]        __lock_acquire+0x1264/0x20b0
[  109.442463]        lock_acquire+0xc2/0x400
[  109.442466]        rt_spin_lock+0x2b/0xc0
[  109.442469]        __local_bh_disable_ip+0xd9/0x270
[  109.442471]        svc_xprt_do_enqueue+0xc0/0x4d0
[  109.442474]        svc_close_list+0x60/0x90
[  109.442476]        svc_close_net+0x49/0x1a0
[  109.442478]        svc_shutdown_net+0x12/0x40
[  109.442480]        nfsd_destroy+0xc5/0x180
[  109.442482]        nfsd+0x1bc/0x270
[  109.442483]        kthread+0x194/0x1b0
[  109.442487]        ret_from_fork+0x22/0x30
[  109.442492]
[  109.442492] other info that might help us debug this:
[  109.442492]
[  109.442493]  Possible unsafe locking scenario:
[  109.442493]
[  109.442493]        CPU0                    CPU1
[  109.442494]        ----                    ----
[  109.442495]   lock(&serv->sv_lock);
[  109.442496]                                lock((softirq_ctrl.lock).lock);
[  109.442498]                                lock(&serv->sv_lock);
[  109.442499]   lock((softirq_ctrl.lock).lock);
[  109.442501]
[  109.442501]  *** DEADLOCK ***
[  109.442501]
[  109.442501] 3 locks held by nfsd/1032:
[  109.442503]  #0: ffffffff93b49258 (nfsd_mutex){+.+.}-{3:3}, at: nfsd+0x19a/0x270
[  109.442508]  #1: ffff994245cb00b0 (&serv->sv_lock){+.+.}-{0:0}, at: svc_close_list+0x1f/0x90
[  109.442512]  #2: ffffffff93a81b20 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock+0x5/0xc0
[  109.442518]
[  109.442518] stack backtrace:
[  109.442519] CPU: 0 PID: 1032 Comm: nfsd Not tainted 5.10.16-rt30 #1
[  109.442522] Hardware name: Supermicro X9DRL-3F/iF/X9DRL-3F/iF, BIOS 3.2 09/22/2015
[  109.442524] Call Trace:
[  109.442527]  dump_stack+0x77/0x97
[  109.442533]  check_noncircular+0xdc/0xf0
[  109.442546]  __lock_acquire+0x1264/0x20b0
[  109.442553]  lock_acquire+0xc2/0x400
[  109.442564]  rt_spin_lock+0x2b/0xc0
[  109.442570]  __local_bh_disable_ip+0xd9/0x270
[  109.442573]  svc_xprt_do_enqueue+0xc0/0x4d0
[  109.442577]  svc_close_list+0x60/0x90
[  109.442581]  svc_close_net+0x49/0x1a0
[  109.442585]  svc_shutdown_net+0x12/0x40
[  109.442588]  nfsd_destroy+0xc5/0x180
[  109.442590]  nfsd+0x1bc/0x270
[  109.442595]  kthread+0x194/0x1b0
[  109.442600]  ret_from_fork+0x22/0x30
[  109.518225] nfsd: last server has exited, flushing export cache
[  OK  ] Stopped NFSv4 ID-name mapping service.
[  OK  ] Stopped GSSAPI Proxy Daemon.
[  OK  ] Stopped NFS Mount Daemon.
[  OK  ] Stopped NFS status monitor for NFSv2/3 locking..

Fixes: 719f8bcc88 ("svcrpc: fix xpt_list traversal locking on shutdown")
Signed-off-by: Joe Korty <joe.korty@concurrent-rt.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-24 11:26:38 +01:00
Benjamin Coddington d5a69ed759 SUNRPC: Set memalloc_nofs_save() for sync tasks
[ Upstream commit f0940f4b3284a00f38a5d42e6067c2aaa20e1f2e ]

We could recurse into NFS doing memory reclaim while sending a sync task,
which might result in a deadlock.  Set memalloc_nofs_save for sync task
execution.

Fixes: a1231fda7e ("SUNRPC: Set memalloc_nofs_save() on all rpciod/xprtiod jobs")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17 17:03:56 +01:00
Dave Wysochanski 618b65dbde SUNRPC: Handle 0 length opaque XDR object data properly
[ Upstream commit e4a7d1f7707eb44fd953a31dd59eff82009d879c ]

When handling an auth_gss downcall, it's possible to get 0-length
opaque object for the acceptor.  In the case of a 0-length XDR
object, make sure simple_get_netobj() fills in dest->data = NULL,
and does not continue to kmemdup() which will set
dest->data = ZERO_SIZE_PTR for the acceptor.

The trace event code can handle NULL but not ZERO_SIZE_PTR for a
string, and so without this patch the rpcgss_context trace event
will crash the kernel as follows:

[  162.887992] BUG: kernel NULL pointer dereference, address: 0000000000000010
[  162.898693] #PF: supervisor read access in kernel mode
[  162.900830] #PF: error_code(0x0000) - not-present page
[  162.902940] PGD 0 P4D 0
[  162.904027] Oops: 0000 [#1] SMP PTI
[  162.905493] CPU: 4 PID: 4321 Comm: rpc.gssd Kdump: loaded Not tainted 5.10.0 #133
[  162.908548] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[  162.910978] RIP: 0010:strlen+0x0/0x20
[  162.912505] Code: 48 89 f9 74 09 48 83 c1 01 80 39 00 75 f7 31 d2 44 0f b6 04 16 44 88 04 11 48 83 c2 01 45 84 c0 75 ee c3 0f 1f 80 00 00 00 00 <80> 3f 00 74 10 48 89 f8 48 83 c0 01 80 38 00 75 f7 48 29 f8 c3 31
[  162.920101] RSP: 0018:ffffaec900c77d90 EFLAGS: 00010202
[  162.922263] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000fffde697
[  162.925158] RDX: 000000000000002f RSI: 0000000000000080 RDI: 0000000000000010
[  162.928073] RBP: 0000000000000010 R08: 0000000000000e10 R09: 0000000000000000
[  162.930976] R10: ffff8e698a590cb8 R11: 0000000000000001 R12: 0000000000000e10
[  162.933883] R13: 00000000fffde697 R14: 000000010034d517 R15: 0000000000070028
[  162.936777] FS:  00007f1e1eb93700(0000) GS:ffff8e6ab7d00000(0000) knlGS:0000000000000000
[  162.940067] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  162.942417] CR2: 0000000000000010 CR3: 0000000104eba000 CR4: 00000000000406e0
[  162.945300] Call Trace:
[  162.946428]  trace_event_raw_event_rpcgss_context+0x84/0x140 [auth_rpcgss]
[  162.949308]  ? __kmalloc_track_caller+0x35/0x5a0
[  162.951224]  ? gss_pipe_downcall+0x3a3/0x6a0 [auth_rpcgss]
[  162.953484]  gss_pipe_downcall+0x585/0x6a0 [auth_rpcgss]
[  162.955953]  rpc_pipe_write+0x58/0x70 [sunrpc]
[  162.957849]  vfs_write+0xcb/0x2c0
[  162.959264]  ksys_write+0x68/0xe0
[  162.960706]  do_syscall_64+0x33/0x40
[  162.962238]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  162.964346] RIP: 0033:0x7f1e1f1e57df

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13 13:52:56 +01:00
Dave Wysochanski 19b56e8433 SUNRPC: Move simple_get_bytes and simple_get_netobj into private header
[ Upstream commit ba6dfce47c4d002d96cd02a304132fca76981172 ]

Remove duplicated helper functions to parse opaque XDR objects
and place inside new file net/sunrpc/auth_gss/auth_gss_internal.h.
In the new file carry the license and copyright from the source file
net/sunrpc/auth_gss/auth_gss.c.  Finally, update the comment inside
include/linux/sunrpc/xdr.h since lockd is not the only user of
struct xdr_netobj.

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13 13:52:56 +01:00
j.nixdorf@avm.de a34294774a net: sunrpc: interpret the return value of kstrtou32 correctly
commit 86b53fbf08f48d353a86a06aef537e78e82ba721 upstream.

A return value of 0 means success. This is documented in lib/kstrtox.c.

This was found by trying to mount an NFS share from a link-local IPv6
address with the interface specified by its index:

  mount("[fe80::1%1]:/srv/nfs", "/mnt", "nfs", 0, "nolock,addr=fe80::1%1")

Before this commit this failed with EINVAL and also caused the following
message in dmesg:

  [...] NFS: bad IP address specified: addr=fe80::1%1

The syscall using the same address based on the interface name instead
of its index succeeds.

Credits for this patch go to my colleague Christian Speich, who traced
the origin of this bug to this line of code.

Signed-off-by: Johannes Nixdorf <j.nixdorf@avm.de>
Fixes: 00cfaa943e ("replace strict_strto calls")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-19 18:26:18 +01:00
Chuck Lever 3ee6a2bc14 xprtrdma: Fix XDRBUF_SPARSE_PAGES support
commit 15261b9126cd5bb2ad8521da49d8f5c042d904c7 upstream.

Olga K. observed that rpcrdma_marsh_req() allocates sparse pages
only when it has determined that a Reply chunk is necessary. There
are plenty of cases where no Reply chunk is needed, but the
XDRBUF_SPARSE_PAGES flag is set. The result would be a crash in
rpcrdma_inline_fixup() when it tries to copy parts of the received
Reply into a missing page.

To avoid crashing, handle sparse page allocation up front.

Until XATTR support was added, this issue did not appear often
because the only SPARSE_PAGES consumer always expected a reply large
enough to always require a Reply chunk.

Reported-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:38 +01:00
Dan Aloni 2d01f3d750 sunrpc: fix xs_read_xdr_buf for partial pages receive
[ Upstream commit ac9645c87380e39a8fa87a1b51721efcdea89dbf ]

When receiving pages data, return value 'ret' when positive includes
`buf->page_base`, so we should subtract that before it is used for
changing `offset` and comparing against `want`.

This was discovered on the very rare cases where the server returned a
chunk of bytes that when added to the already received amount of bytes
for the pages happened to match the current `recv.len`, for example
on this case:

     buf->page_base : 258356
     actually received from socket: 1740
     ret : 260096
     want : 260096

In this case neither of the two 'if ... goto out' trigger, and we
continue to tail parsing.

Worth to mention that the ensuing EMSGSIZE from the continued execution of
`xs_read_xdr_buf` may be observed by an application due to 4 superfluous
bytes being added to the pages data.

Fixes: 277e4ab7d5 ("SUNRPC: Simplify TCP receive code by switching to using iterators")
Signed-off-by: Dan Aloni <dan@kernelim.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:26 +01:00
Fedor Tokarev cbb0a57326 net: sunrpc: Fix 'snprintf' return value check in 'do_xprt_debugfs'
[ Upstream commit 35a6d396721e28ba161595b0fc9e8896c00399bb ]

'snprintf' returns the number of characters which would have been written
if enough space had been available, excluding the terminating null byte.
Thus, the return value of 'sizeof(buf)' means that the last character
has been dropped.

Signed-off-by: Fedor Tokarev <ftokarev@gmail.com>
Fixes: 2f34b8bfae ("SUNRPC: add links for all client xprts to debugfs")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:16 +01:00
Trond Myklebust 73892eef6d SUNRPC: xprt_load_transport() needs to support the netid "rdma6"
[ Upstream commit d5aa6b22e2258f05317313ecc02efbb988ed6d38 ]

According to RFC5666, the correct netid for an IPv6 addressed RDMA
transport is "rdma6", which we've supported as a mount option since
Linux-4.7. The problem is when we try to load the module "xprtrdma6",
that will fail, since there is no modulealias of that name.

Fixes: 181342c5eb ("xprtrdma: Add rdma6 option to support NFS/RDMA IPv6")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:16 +01:00
Trond Myklebust 04e9c16981 SUNRPC: rpc_wake_up() should wake up tasks in the correct order
[ Upstream commit e4c72201b6ec3173dfe13fa2e2335a3ad78d4921 ]

Currently, we wake up the tasks by priority queue ordering, which means
that we ignore the batching that is supposed to help with QoS issues.

Fixes: c049f8ea9a ("SUNRPC: Remove the bh-safe lock requirement on the rpc_wait_queue->lock")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:51:15 +01:00
Chuck Lever ea888a14ac SUNRPC: Mitigate cond_resched() in xprt_transmit()
[ Upstream commit 6f9f17287e78e5049931af2037b15b26d134a32a ]

The original purpose of this expensive call is to prevent a long
queue of requests from blocking other work.

The cond_resched() call is unnecessary after just a single send
operation.

For longer queues, instead of invoking the kernel scheduler, simply
release the transport send lock and return to the RPC scheduler.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-05 11:43:18 +01:00
Martijn de Gouw 6498597aeb SUNRPC: fix copying of multiple pages in gss_read_proxy_verf()
[ Upstream commit d48c8124749c9a5081fe68680f83605e272c984b ]

When the passed token is longer than 4032 bytes, the remaining part
of the token must be copied from the rqstp->rq_arg.pages. But the
copy must make sure it happens in a consecutive way.

With the existing code, the first memcpy copies 'length' bytes from
argv->iobase, but since the header is in front, this never fills the
whole first page of in_token->pages.

The mecpy in the loop copies the following bytes, but starts writing at
the next page of in_token->pages.  This leaves the last bytes of page 0
unwritten.

Symptoms were that users with many groups were not able to access NFS
exports, when using Active Directory as the KDC.

Signed-off-by: Martijn de Gouw <martijn.de.gouw@prodrive-technologies.com>
Fixes: 5866efa8cbfb "SUNRPC: Fix svcauth_gss_proxy_init()"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29 09:57:56 +01:00
Dan Aloni 9c27185e12 svcrdma: fix bounce buffers for unaligned offsets and multiple pages
[ Upstream commit c327a310ec4d6ecbea13185ed56c11def441d9ab ]

This was discovered using O_DIRECT at the client side, with small
unaligned file offsets or IOs that span multiple file pages.

Fixes: e248aa7be8 ("svcrdma: Remove max_sge check at connect time")
Signed-off-by: Dan Aloni <dan@kernelim.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29 09:57:55 +01:00
Chuck Lever 55c3e7fac9 svcrdma: Fix backchannel return code
[ Upstream commit ea740bd5f58e2912e74f401fd01a9d6aa985ca05 ]

Way back when I was writing the RPC/RDMA server-side backchannel
code, I misread the TCP backchannel reply handler logic. When
svc_tcp_recvfrom() successfully receives a backchannel reply, it
does not return -EAGAIN. It sets XPT_DATA and returns zero.

Update svc_rdma_recvfrom() to return zero. Here, XPT_DATA doesn't
need to be set again: it is set whenever a new message is received,
behind a spin lock in a single threaded context.

Also, if handling the cb reply is not successful, the message is
simply dropped. There's no special message framing to deal with as
there is in the TCP case.

Now that the handle_bc_reply() return value is ignored, I've removed
the dprintk call sites in the error exit of handle_bc_reply() in
favor of trace points in other areas that already report the error
cases.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 13:18:01 +02:00
Trond Myklebust 5e3c0dae5f SUNRPC: Don't start a timer on an already queued rpc task
[ Upstream commit 1fab7dc477241c12f977955aa6baea7938b6f08d ]

Move the test for whether a task is already queued to prevent
corruption of the timer list in __rpc_sleep_on_priority_timeout().

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 13:17:53 +02:00
Chuck Lever cf2d7883e8 svcrdma: Fix leak of transport addresses
[ Upstream commit 1a33d8a284b1e85e03b8c7b1ea8fb985fccd1d71 ]

Kernel memory leak detected:

unreferenced object 0xffff888849cdf480 (size 8):
  comm "kworker/u8:3", pid 2086, jiffies 4297898756 (age 4269.856s)
  hex dump (first 8 bytes):
    30 00 cd 49 88 88 ff ff                          0..I....
  backtrace:
    [<00000000acfc370b>] __kmalloc_track_caller+0x137/0x183
    [<00000000a2724354>] kstrdup+0x2b/0x43
    [<0000000082964f84>] xprt_rdma_format_addresses+0x114/0x17d [rpcrdma]
    [<00000000dfa6ed00>] xprt_setup_rdma_bc+0xc0/0x10c [rpcrdma]
    [<0000000073051a83>] xprt_create_transport+0x3f/0x1a0 [sunrpc]
    [<0000000053531a8e>] rpc_create+0x118/0x1cd [sunrpc]
    [<000000003a51b5f8>] setup_callback_client+0x1a5/0x27d [nfsd]
    [<000000001bd410af>] nfsd4_process_cb_update.isra.7+0x16c/0x1ac [nfsd]
    [<000000007f4bbd56>] nfsd4_run_cb_work+0x4c/0xbd [nfsd]
    [<0000000055c5586b>] process_one_work+0x1b2/0x2fe
    [<00000000b1e3e8ef>] worker_thread+0x1a6/0x25a
    [<000000005205fb78>] kthread+0xf6/0xfb
    [<000000006d2dc057>] ret_from_fork+0x3a/0x50

Introduce a call to xprt_rdma_free_addresses() similar to the way
that the TCP backchannel releases a transport's peer address
strings.

Fixes: 5d252f90a8 ("svcrdma: Add class for RDMA backwards direction transport")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 13:17:50 +02:00
Christophe JAILLET 5f8174bfb9 SUNRPC: Fix a potential buffer overflow in 'svc_print_xprts()'
[ Upstream commit b25b60d7bfb02a74bc3c2d998e09aab159df8059 ]

'maxlen' is the total size of the destination buffer. There is only one
caller and this value is 256.

When we compute the size already used and what we would like to add in
the buffer, the trailling NULL character is not taken into account.
However, this trailling character will be added by the 'strcat' once we
have checked that we have enough place.

So, there is a off-by-one issue and 1 byte of the stack could be
erroneously overwridden.

Take into account the trailling NULL, when checking if there is enough
place in the destination buffer.

While at it, also replace a 'sprintf' by a safer 'snprintf', check for
output truncation and avoid a superfluous 'strlen'.

Fixes: dc9a16e49d ("svc: Add /proc/sys/sunrpc/transport files")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
[ cel: very minor fix to documenting comment
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 13:17:50 +02:00
Chuck Lever 3ce5297c0b SUNRPC: Capture completion of all RPC tasks
[ Upstream commit a264abad51d8ecb7954a2f6d9f1885b38daffc74 ]

RPC tasks on the backchannel never invoke xprt_complete_rqst(), so
there is no way to report their tk_status at completion. Also, any
RPC task that exits via rpc_exit_task() before it is replied to will
also disappear without a trace.

Introduce a trace point that is symmetrical with rpc_task_begin that
captures the termination status of each RPC task.

Sample trace output for callback requests initiated on the server:
   kworker/u8:12-448   [003]   127.025240: rpc_task_end:         task:50@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task
   kworker/u8:12-448   [002]   127.567310: rpc_task_end:         task:51@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task
   kworker/u8:12-448   [001]   130.506817: rpc_task_end:         task:52@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task

Odd, though, that I never see trace_rpc_task_complete, either in the
forward or backchannel. Should it be removed?

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 13:17:21 +02:00
J. Bruce Fields b85406bf1b SUNRPC: stop printk reading past end of string
[ Upstream commit 8c6b6c793ed32b8f9770ebcdf1ba99af423c303b ]

Since p points at raw xdr data, there's no guarantee that it's NULL
terminated, so we should give a length.  And probably escape any special
characters too.

Reported-by: Zhi Li <yieli@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-23 12:40:36 +02:00
Chuck Lever 8fe5e38acb svcrdma: Fix another Receive buffer leak
[ Upstream commit 64d26422516b2e347b32e6d9b1d40b3c19a62aae ]

During a connection tear down, the Receive queue is flushed before
the device resources are freed. Typically, all the Receives flush
with IB_WR_FLUSH_ERR.

However, any pending successful Receives flush with IB_WR_SUCCESS,
and the server automatically posts a fresh Receive to replace the
completing one. This happens even after the connection has closed
and the RQ is drained. Receives that are posted after the RQ is
drained appear never to complete, causing a Receive resource leak.
The leaked Receive buffer is left DMA-mapped.

To prevent these late-posted recv_ctxt's from leaking, block new
Receive posting after XPT_CLOSE is set.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26 10:40:55 +02:00
Chuck Lever 18d1bb4973 SUNRPC: Fix ("SUNRPC: Add "@len" parameter to gss_unwrap()")
[ 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>
2020-08-19 08:16:21 +02:00
Chuck Lever 789be9705e svcrdma: Fix page leak in svc_rdma_recv_read_chunk()
[ Upstream commit e814eecbe3bbeaa8b004d25a4b8974d232b765a9 ]

Commit 07d0ff3b0c ("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: 07d0ff3b0c ("svcrdma: Clean up Read chunk path")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19 08:16:21 +02:00
Chuck Lever 512570b178 nfsd: Fix NFSv4 READ on RDMA when using readv
commit 412055398b9e67e07347a936fc4a6adddabe9cf4 upstream.

svcrdma expects that the payload falls precisely into the xdr_buf
page vector. This does not seem to be the case for
nfsd4_encode_readv().

This code is called only when fops->splice_read is missing or when
RQ_SPLICE_OK is clear, so it's not a noticeable problem in many
common cases.

Add new transport method: ->xpo_read_payload so that when a READ
payload does not fit exactly in rq_res's page vector, the XDR
encoder can inform the RPC transport exactly where that payload is,
without the payload's XDR pad.

That way, when a Write chunk is present, the transport knows what
byte range in the Reply message is supposed to be matched with the
chunk.

Note that the Linux NFS server implementation of NFS/RDMA can
currently handle only one Write chunk per RPC-over-RDMA message.
This simplifies the implementation of this fix.

Fixes: b042098063 ("nfsd4: allow exotic read compounds")
Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=198053
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Timo Rothenpieler <timo@rothenpieler.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-11 15:33:42 +02:00
Sasha Levin 98cef10fbc sunrpc: check that domain table is empty at module unload.
[ Upstream commit f45db2b909c7e76f35850e78f017221f30282b8e ]

The domain table should be empty at module unload.  If it isn't there is
a bug somewhere.  So check and report.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206651
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-05 09:59:41 +02:00
Colin Ian King c8a4452da9 xprtrdma: fix incorrect header size calculations
[ Upstream commit 912288442cb2f431bf3c8cb097a5de83bc6dbac1 ]

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: 302d3deb20 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-22 09:33:03 +02:00
Chuck Lever de1d70dad6 xprtrdma: Fix handling of RDMA_ERROR replies
commit 7b2182ec381f8ea15c7eb1266d6b5d7da620ad93 upstream.

The RPC client currently doesn't handle ERR_CHUNK replies correctly.
rpcrdma_complete_rqst() incorrectly passes a negative number to
xprt_complete_rqst() as the number of bytes copied. Instead, set
task->tk_status to the error value, and return zero bytes copied.

In these cases, return -EIO rather than -EREMOTEIO. The RPC client's
finite state machine doesn't know what to do with -EREMOTEIO.

Additional clean ups:
- Don't double-count RDMA_ERROR replies
- Remove a stale comment

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@kernel.vger.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:37:12 -04:00
Chuck Lever 7b99577ff3 SUNRPC: Properly set the @subbuf parameter of xdr_buf_subsegment()
commit 89a3c9f5b9f0bcaa9aea3e8b2a616fcaea9aad78 upstream.

@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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:37:12 -04:00
Vasily Averin c27d205baa sunrpc: fixed rollback in rpc_gssd_dummy_populate()
commit b7ade38165ca0001c5a3bd5314a314abbbfbb1b7 upstream.

__rpc_depopulate(gssd_dentry) was lost on error path

cc: stable@vger.kernel.org
Fixes: commit 4b9a445e3e ("sunrpc: create a new dummy pipe for gssd to hold open")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:37:11 -04:00
Fedor Tokarev 5e85d78ed4 net: sunrpc: Fix off-by-one issues in 'rpc_ntop6'
[ Upstream commit 118917d696dc59fd3e1741012c2f9db2294bed6f ]

Fix off-by-one issues in 'rpc_ntop6':
 - 'snprintf' returns the number of characters which would have been
   written if enough space had been available, excluding the terminating
   null byte. Thus, a return value of 'sizeof(scopebuf)' means that the
   last character was dropped.
 - 'strcat' adds a terminating null byte to the string, thus if len ==
   buflen, the null byte is written past the end of the buffer.

Signed-off-by: Fedor Tokarev <ftokarev@gmail.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24 17:50:35 +02:00
NeilBrown e5084eadf1 sunrpc: clean up properly in gss_mech_unregister()
commit 24c5efe41c29ee3e55bcf5a1c9f61ca8709622e8 upstream.

gss_mech_register() calls svcauth_gss_register_pseudoflavor() for each
flavour, but gss_mech_unregister() does not call auth_domain_put().
This is unbalanced and makes it impossible to reload the module.

Change svcauth_gss_register_pseudoflavor() to return the registered
auth_domain, and save it for later release.

Cc: stable@vger.kernel.org (v2.6.12+)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206651
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-22 09:31:24 +02:00
NeilBrown 4a68a2e25e sunrpc: svcauth_gss_register_pseudoflavor must reject duplicate registrations.
commit d47a5dc2888fd1b94adf1553068b8dad76cec96c upstream.

There is no valid case for supporting duplicate pseudoflavor
registrations.
Currently the silent acceptance of such registrations is hiding a bug.
The rpcsec_gss_krb5 module registers 2 flavours but does not unregister
them, so if you load, unload, reload the module, it will happily
continue to use the old registration which now has pointers to the
memory were the module was originally loaded.  This could lead to
unexpected results.

So disallow duplicate registrations.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206651
Cc: stable@vger.kernel.org (v2.6.12+)
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-22 09:31:24 +02:00
Chuck Lever d41689a34a SUNRPC: Revert 241b1f419f ("SUNRPC: Remove xdr_buf_trim()")
commit 0a8e7b7d08466b5fc52f8e96070acc116d82a8bb upstream.

I've noticed that when krb5i or krb5p security is in use,
retransmitted requests are missing the server's duplicate reply
cache. The computed checksum on the retransmitted request does not
match the cached checksum, resulting in the server performing the
retransmitted request again instead of returning the cached reply.

The assumptions made when removing xdr_buf_trim() were not correct.
In the send paths, the upper layer has already set the segment
lengths correctly, and shorting the buffer's content is simply a
matter of reducing buf->len.

xdr_buf_trim() is the right answer in the receive/unwrap path on
both the client and the server. The buffer segment lengths have to
be shortened one-by-one.

On the server side in particular, head.iov_len needs to be updated
correctly to enable nfsd_cache_csum() to work correctly. The simple
buf->len computation doesn't do that, and that results in
checksumming stale data in the buffer.

The problem isn't noticed until there's significant instability of
the RPC transport. At that point, the reliability of retransmit
detection on the server becomes crucial.

Fixes: 241b1f419f ("SUNRPC: Remove xdr_buf_trim()")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:20:39 +02:00
Chuck Lever 6259b1c1bc SUNRPC: Signalled ASYNC tasks need to exit
[ Upstream commit ce99aa62e1eb793e259d023c7f6ccb7c4879917b ]

Ensure that signalled ASYNC rpc_tasks exit immediately instead of
spinning until a timeout (or forever).

To avoid checking for the signal flag on every scheduler iteration,
the check is instead introduced in the client's finite state
machine.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Fixes: ae67bd3821 ("SUNRPC: Fix up task signalling")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:20:24 +02:00
Chuck Lever e15d3d4290 SUNRPC: Fix GSS privacy computation of auth->au_ralign
[ Upstream commit a7e429a6fa6d612d1dacde96c885dc1bb4a9f400 ]

When the au_ralign field was added to gss_unwrap_resp_priv, the
wrong calculation was used. Setting au_rslack == au_ralign is
probably correct for kerberos_v1 privacy, but kerberos_v2 privacy
adds additional GSS data after the clear text RPC message.
au_ralign needs to be smaller than au_rslack in that fairly common
case.

When xdr_buf_trim() is restored to gss_unwrap_kerberos_v2(), it does
exactly what I feared it would: it trims off part of the clear text
RPC message. However, that's because rpc_prepare_reply_pages() does
not set up the rq_rcv_buf's tail correctly because au_ralign is too
large.

Fixing the au_ralign computation also corrects the alignment of
rq_rcv_buf->pages so that the client does not have to shift reply
data payloads after they are received.

Fixes: 35e77d21ba ("SUNRPC: Add rpc_auth::au_ralign field")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:20:05 +02:00
Chuck Lever 3bf0794e73 SUNRPC: Add "@len" parameter to gss_unwrap()
[ Upstream commit 31c9590ae468478fe47dc0f5f0d3562b2f69450e ]

Refactor: This is a pre-requisite to fixing the client-side ralign
computation in gss_unwrap_resp_priv().

The length value is passed in explicitly rather that as the value
of buf->len. This will subsequently allow gss_unwrap_kerberos_v1()
to compute a slack and align value, instead of computing it in
gss_unwrap_resp_priv().

Fixes: 35e77d21ba ("SUNRPC: Add rpc_auth::au_ralign field")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:20:04 +02:00
Chuck Lever b4284efb1e svcrdma: Fix leak of svc_rdma_recv_ctxt objects
commit 23cf1ee1f1869966b75518c59b5cbda4c6c92450 upstream.

Utilize the xpo_release_rqst transport method to ensure that each
rqstp's svc_rdma_recv_ctxt object is released even when the server
cannot return a Reply for that rqstp.

Without this fix, each RPC whose Reply cannot be sent leaks one
svc_rdma_recv_ctxt. This is a 2.5KB structure, a 4KB DMA-mapped
Receive buffer, and any pages that might be part of the Reply
message.

The leak is infrequent unless the network fabric is unreliable or
Kerberos is in use, as GSS sequence window overruns, which result
in connection loss, are more common on fast transports.

Fixes: 3a88092ee3 ("svcrdma: Preserve Receive buffer until svc_rdma_sendto")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 08:48:48 +02:00
Chuck Lever 53dbb934dd svcrdma: Fix trace point use-after-free race
commit e28b4fc652c1830796a4d3e09565f30c20f9a2cf upstream.

I hit this while testing nfsd-5.7 with kernel memory debugging
enabled on my server:

Mar 30 13:21:45 klimt kernel: BUG: unable to handle page fault for address: ffff8887e6c279a8
Mar 30 13:21:45 klimt kernel: #PF: supervisor read access in kernel mode
Mar 30 13:21:45 klimt kernel: #PF: error_code(0x0000) - not-present page
Mar 30 13:21:45 klimt kernel: PGD 3601067 P4D 3601067 PUD 87c519067 PMD 87c3e2067 PTE 800ffff8193d8060
Mar 30 13:21:45 klimt kernel: Oops: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
Mar 30 13:21:45 klimt kernel: CPU: 2 PID: 1933 Comm: nfsd Not tainted 5.6.0-rc6-00040-g881e87a3c6f9 #1591
Mar 30 13:21:45 klimt kernel: Hardware name: Supermicro Super Server/X10SRL-F, BIOS 1.0c 09/09/2015
Mar 30 13:21:45 klimt kernel: RIP: 0010:svc_rdma_post_chunk_ctxt+0xab/0x284 [rpcrdma]
Mar 30 13:21:45 klimt kernel: Code: c1 83 34 02 00 00 29 d0 85 c0 7e 72 48 8b bb a0 02 00 00 48 8d 54 24 08 4c 89 e6 48 8b 07 48 8b 40 20 e8 5a 5c 2b e1 41 89 c6 <8b> 45 20 89 44 24 04 8b 05 02 e9 01 00 85 c0 7e 33 e9 5e 01 00 00
Mar 30 13:21:45 klimt kernel: RSP: 0018:ffffc90000dfbdd8 EFLAGS: 00010286
Mar 30 13:21:45 klimt kernel: RAX: 0000000000000000 RBX: ffff8887db8db400 RCX: 0000000000000030
Mar 30 13:21:45 klimt kernel: RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000246
Mar 30 13:21:45 klimt kernel: RBP: ffff8887e6c27988 R08: 0000000000000000 R09: 0000000000000004
Mar 30 13:21:45 klimt kernel: R10: ffffc90000dfbdd8 R11: 00c068ef00000000 R12: ffff8887eb4e4a80
Mar 30 13:21:45 klimt kernel: R13: ffff8887db8db634 R14: 0000000000000000 R15: ffff8887fc931000
Mar 30 13:21:45 klimt kernel: FS:  0000000000000000(0000) GS:ffff88885bd00000(0000) knlGS:0000000000000000
Mar 30 13:21:45 klimt kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Mar 30 13:21:45 klimt kernel: CR2: ffff8887e6c279a8 CR3: 000000081b72e002 CR4: 00000000001606e0
Mar 30 13:21:45 klimt kernel: Call Trace:
Mar 30 13:21:45 klimt kernel: ? svc_rdma_vec_to_sg+0x7f/0x7f [rpcrdma]
Mar 30 13:21:45 klimt kernel: svc_rdma_send_write_chunk+0x59/0xce [rpcrdma]
Mar 30 13:21:45 klimt kernel: svc_rdma_sendto+0xf9/0x3ae [rpcrdma]
Mar 30 13:21:45 klimt kernel: ? nfsd_destroy+0x51/0x51 [nfsd]
Mar 30 13:21:45 klimt kernel: svc_send+0x105/0x1e3 [sunrpc]
Mar 30 13:21:45 klimt kernel: nfsd+0xf2/0x149 [nfsd]
Mar 30 13:21:45 klimt kernel: kthread+0xf6/0xfb
Mar 30 13:21:45 klimt kernel: ? kthread_queue_delayed_work+0x74/0x74
Mar 30 13:21:45 klimt kernel: ret_from_fork+0x3a/0x50
Mar 30 13:21:45 klimt kernel: Modules linked in: ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue ib_umad ib_ipoib mlx4_ib sb_edac x86_pkg_temp_thermal iTCO_wdt iTCO_vendor_support coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel glue_helper crypto_simd cryptd pcspkr rpcrdma i2c_i801 rdma_ucm lpc_ich mfd_core ib_iser rdma_cm iw_cm ib_cm mei_me raid0 libiscsi mei sg scsi_transport_iscsi ioatdma wmi ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter nfsd nfs_acl lockd auth_rpcgss grace sunrpc ip_tables xfs libcrc32c mlx4_en sd_mod sr_mod cdrom mlx4_core crc32c_intel igb nvme i2c_algo_bit ahci i2c_core libahci nvme_core dca libata t10_pi qedr dm_mirror dm_region_hash dm_log dm_mod dax qede qed crc8 ib_uverbs ib_core
Mar 30 13:21:45 klimt kernel: CR2: ffff8887e6c279a8
Mar 30 13:21:45 klimt kernel: ---[ end trace 87971d2ad3429424 ]---

It's absolutely not safe to use resources pointed to by the @send_wr
argument of ib_post_send() _after_ that function returns. Those
resources are typically freed by the Send completion handler, which
can run before ib_post_send() returns.

Thus the trace points currently around ib_post_send() in the
server's RPC/RDMA transport are a hazard, even when they are
disabled. Rearrange them so that they touch the Work Request only
_before_ ib_post_send() is invoked.

Fixes: bd2abef333 ("svcrdma: Trace key RDMA API events")
Fixes: 4201c74647 ("svcrdma: Introduce svc_rdma_send_ctxt")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 08:48:48 +02:00
Chuck Lever 7e69c9e6bb SUNRPC: Fix backchannel RPC soft lockups
commit 6221f1d9b63fed6260273e59a2b89ab30537a811 upstream.

Currently, after the forward channel connection goes away,
backchannel operations are causing soft lockups on the server
because call_transmit_status's SOFTCONN logic ignores ENOTCONN.
Such backchannel Calls are aggressively retried until the client
reconnects.

Backchannel Calls should use RPC_TASK_NOCONNECT rather than
RPC_TASK_SOFTCONN. If there is no forward connection, the server is
not capable of establishing a connection back to the client, thus
that backchannel request should fail before the server attempts to
send it. Commit 58255a4e3c ("NFSD: NFSv4 callback client should
use RPC_TASK_SOFTCONN") was merged several years before
RPC_TASK_NOCONNECT was available.

Because setup_callback_client() explicitly sets NOPING, the NFSv4.0
callback connection depends on the first callback RPC to initiate
a connection to the client. Thus NFSv4.0 needs to continue to use
RPC_TASK_SOFTCONN.

Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org> # v4.20+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29 16:33:18 +02:00
Chuck Lever 1500c70031 sunrpc: Fix gss_unwrap_resp_integ() again
[ Upstream commit 4047aa909c4a40fceebc36fff708d465a4d3c6e2 ]

xdr_buf_read_mic() tries to find unused contiguous space in a
received xdr_buf in order to linearize the checksum for the call
to gss_verify_mic. However, the corner cases in this code are
numerous and we seem to keep missing them. I've just hit yet
another buffer overrun related to it.

This overrun is at the end of xdr_buf_read_mic():

1284         if (buf->tail[0].iov_len != 0)
1285                 mic->data = buf->tail[0].iov_base + buf->tail[0].iov_len;
1286         else
1287                 mic->data = buf->head[0].iov_base + buf->head[0].iov_len;
1288         __read_bytes_from_xdr_buf(&subbuf, mic->data, mic->len);
1289         return 0;

This logic assumes the transport has set the length of the tail
based on the size of the received message. base + len is then
supposed to be off the end of the message but still within the
actual buffer.

In fact, the length of the tail is set by the upper layer when the
Call is encoded so that the end of the tail is actually the end of
the allocated buffer itself. This causes the logic above to set
mic->data to point past the end of the receive buffer.

The "mic->data = head" arm of this if statement is no less fragile.

As near as I can tell, this has been a problem forever. I'm not sure
that minimizing au_rslack recently changed this pathology much.

So instead, let's use a more straightforward approach: kmalloc a
separate buffer to linearize the checksum. This is similar to
how gss_validate() currently works.

Coming back to this code, I had some trouble understanding what
was going on. So I've cleaned up the variable naming and added
a few comments that point back to the XDR definition in RFC 2203
to help guide future spelunkers, including myself.

As an added clean up, the functionality that was in
xdr_buf_read_mic() is folded directly into gss_unwrap_resp_integ(),
as that is its only caller.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-23 10:36:41 +02:00
Olga Kornievskaia d00041a48c SUNRPC: fix krb5p mount to provide large enough buffer in rq_rcvsize
[ Upstream commit df513a7711712758b9cb1a48d86712e7e1ee03f4 ]

Ever since commit 2c94b8eca1 ("SUNRPC: Use au_rslack when computing
reply buffer size"). It changed how "req->rq_rcvsize" is calculated. It
used to use au_cslack value which was nice and large and changed it to
au_rslack value which turns out to be too small.

Since 5.1, v3 mount with sec=krb5p fails against an Ontap server
because client's receive buffer it too small.

For gss krb5p, we need to account for the mic token in the verifier,
and the wrap token in the wrap token.

RFC 4121 defines:
mic token
Octet no   Name        Description
         --------------------------------------------------------------
         0..1     TOK_ID     Identification field.  Tokens emitted by
                             GSS_GetMIC() contain the hex value 04 04
                             expressed in big-endian order in this
                             field.
         2        Flags      Attributes field, as described in section
                             4.2.2.
         3..7     Filler     Contains five octets of hex value FF.
         8..15    SND_SEQ    Sequence number field in clear text,
                             expressed in big-endian order.
         16..last SGN_CKSUM  Checksum of the "to-be-signed" data and
                             octet 0..15, as described in section 4.2.4.

that's 16bytes (GSS_KRB5_TOK_HDR_LEN) + chksum

wrap token
Octet no   Name        Description
         --------------------------------------------------------------
          0..1     TOK_ID    Identification field.  Tokens emitted by
                             GSS_Wrap() contain the hex value 05 04
                             expressed in big-endian order in this
                             field.
          2        Flags     Attributes field, as described in section
                             4.2.2.
          3        Filler    Contains the hex value FF.
          4..5     EC        Contains the "extra count" field, in big-
                             endian order as described in section 4.2.3.
          6..7     RRC       Contains the "right rotation count" in big-
                             endian order, as described in section
                             4.2.5.
          8..15    SND_SEQ   Sequence number field in clear text,
                             expressed in big-endian order.
          16..last Data      Encrypted data for Wrap tokens with
                             confidentiality, or plaintext data followed
                             by the checksum for Wrap tokens without
                             confidentiality, as described in section
                             4.2.4.

Also 16bytes of header (GSS_KRB5_TOK_HDR_LEN), encrypted data, and cksum
(other things like padding)

RFC 3961 defines known cksum sizes:
Checksum type              sumtype        checksum         section or
                                value            size         reference
   ---------------------------------------------------------------------
   CRC32                            1               4           6.1.3
   rsa-md4                          2              16           6.1.2
   rsa-md4-des                      3              24           6.2.5
   des-mac                          4              16           6.2.7
   des-mac-k                        5               8           6.2.8
   rsa-md4-des-k                    6              16           6.2.6
   rsa-md5                          7              16           6.1.1
   rsa-md5-des                      8              24           6.2.4
   rsa-md5-des3                     9              24             ??
   sha1 (unkeyed)                  10              20             ??
   hmac-sha1-des3-kd               12              20            6.3
   hmac-sha1-des3                  13              20             ??
   sha1 (unkeyed)                  14              20             ??
   hmac-sha1-96-aes128             15              20         [KRB5-AES]
   hmac-sha1-96-aes256             16              20         [KRB5-AES]
   [reserved]                  0x8003               ?         [GSS-KRB5]

Linux kernel now mainly supports type 15,16 so max cksum size is 20bytes.
(GSS_KRB5_MAX_CKSUM_LEN)

Re-use already existing define of GSS_KRB5_MAX_SLACK_NEEDED that's used
for encoding the gss_wrap tokens (same tokens are used in reply).

Fixes: 2c94b8eca1 ("SUNRPC: Use au_rslack when computing reply buffer size")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-23 10:36:40 +02:00
Trond Myklebust 707518c16b sunrpc: Fix potential leaks in sunrpc_cache_unhash()
[ Upstream commit 1d82163714c16ebe09c7a8c9cd3cef7abcc16208 ]

When we unhash the cache entry, we need to handle any pending upcalls
by calling cache_fresh_unlocked().

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:55 +01:00
Chuck Lever ff04f342f8 xprtrdma: Fix DMA scatter-gather list mapping imbalance
commit ca1c671302825182629d3c1a60363cee6f5455bb upstream.

The @nents value that was passed to ib_dma_map_sg() has to be passed
to the matching ib_dma_unmap_sg() call. If ib_dma_map_sg() choses to
concatenate sg entries, it will return a different nents value than
it was passed.

The bug was exposed by recent changes to the AMD IOMMU driver, which
enabled sg entry concatenation.

Looking all the way back to commit 4143f34e01 ("xprtrdma: Port to
new memory registration API") and reviewing other kernel ULPs, it's
not clear that the frwr_map() logic was ever correct for this case.

Reported-by: Andre Tomt <andre@tomt.net>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 19:53:02 +01:00