During a recent testing event, it was reported that the NFSv4.1/4.2
server erroneously bound the back channel to a new TCP connection.
RFC5661 specifies that the fore channel is implicitly bound to a
new TCP connection when an RPC with Sequence (almost any of them)
is done on it. For the back channel to be bound to the new TCP
connection, an explicit BindConnectionToSession must be done as
the first RPC on the new connection.
Since new TCP connections are created by the "reconnect" layer
(sys/rpc/clnt_rc.c) of the krpc, this patch adds an optional
upcall done by the krpc whenever a new connection is created.
The patch also adds the specific upcall function that does a
BindConnectionToSession and configures the krpc to call it
when required.
This is necessary for correct interoperability with NFSv4.1/NFSv4.2
servers when the nfscbd daemon is running.
If doing NFSv4.1/NFSv4.2 mounts without this patch, it is
recommended that the nfscbd daemon not be running and that
the "pnfs" mount option not be specified.
PR: 254840
Comments by: asomers
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D29475
When the server side nfs-over-tls does an upcall to rpc.tlsservd(8)
for the handshake and the rpc.tlsservd "-u" command line option has
been specified, a list of gids may be returned.
The list will be returned in malloc'd memory pointed to by
res.gid.gid_val. To ensure the malloc occurs, res.gid.gid_val must
be NULL before the call. Then, the malloc'd memory needs to be free'd.
mem_free() just calls free(9), so a NULL pointer argument is fine
and a length argument == 0 is ok, since the "len" argument is not used.
This bug would have only affected nfs-over-tls and only when
rpc.tlsservd(8) is running with the "-u" command line option.
When using NFS-over-TLS, an NFS client can optionally provide an X.509
certificate to the server during the TLS handshake. For some situations,
such as different NFS servers or different certificates being mapped
to different user credentials on the NFS server, there may be a need
for different mounts to provide different certificates.
This new mount option called "tlscertname" may be used to specify a
non-default certificate be provided. This alernate certificate will
be stored in /etc/rpc.tlsclntd in a file with a name based on what is
provided by this mount option.
For the TLS case where there is a "user@domain" name specified in the
X.509 v3 certificate presented by the client in the otherName component
of subjectAltName, a gid list is allocated via mem_alloc().
This needs to be free'd. Otherwise xp_gidp == NULL and free() handles that.
(The size argument to mem_free() is not used by FreeBSD, so it can be 0.)
This leak would not have occurred for any other case than NFS over TLS
with the "user@domain" in the client's certificate.
An internet draft titled "Towards Remote Procedure Call Encryption By Default"
describes how TLS is to be used for Sun RPC, with NFS as an intended use case.
This patch adds client and server support for this to the kernel RPC,
using KERN_TLS and upcalls to daemons for the handshake, peer reset and
other non-application data record cases.
The upcalls to the daemons use three fields to uniquely identify the
TCP connection. They are the time.tv_sec, time.tv_usec of the connection
establshment, plus a 64bit sequence number. The time fields avoid problems
with re-use of the sequence number after a daemon restart.
For the server side, once a Null RPC with AUTH_TLS is received, kernel
reception on the socket is blocked and an upcall to the rpctlssd(8) daemon
is done to perform the TLS handshake. Upon completion, the completion
status of the handshake is stored in xp_tls as flag bits and the reply to
the Null RPC is sent.
For the client, if CLSET_TLS has been set, a new TCP connection will
send the Null RPC with AUTH_TLS to initiate the handshake. The client
kernel RPC code will then block kernel I/O on the socket and do an upcall
to the rpctlscd(8) daemon to perform the handshake.
If the upcall is successful, ct_rcvstate will be maintained to indicate
if/when an upcall is being done.
If non-application data records are received, the code does an upcall to
the appropriate daemon, which will do a SSL_read() of 0 length to handle
the record(s).
When the socket is being shut down, upcalls are done to the daemons, so
that they can perform SSL_shutdown() calls to perform the "peer reset".
The rpctlssd(8) and rpctlscd(8) daemons require a patched version of the
openssl library and, as such, will not be committed to head at this time.
Although the changes done by this patch are fairly numerous, there should
be no semantics change to the kernel RPC at this time.
A future commit to the NFS code will optionally enable use of TLS for NFS.
For NFSv4.0, the server creates a server->client TCP connection for callbacks.
If the client mount on the server is using TLS, enable TLS for this callback
TCP connection.
TLS connections from clients will not be supported until the kernel RPC
changes are committed.
Since this changes the internal ABI between the NFS kernel modules that
will require a version bump, delete newnfs_trimtrailing(), which is no
longer used.
Since LCL_TLSCB is not yet set, these changes should not have any semantic
affect at this time.
Without this patch, clnt_vc_soupcall() first does a soreceive() for
4 bytes (the Sun RPC over TCP record mark) and then soreceive(s) for
the RPC message.
This first soreceive() almost always results in an mbuf allocation,
since having the 4byte record mark in a separate mbuf in the socket
rcv queue is unlikely.
This is somewhat inefficient and rather odd. It also will not work
for the ktls rx, since the latter returns a TLS record for each
soreceive().
This patch replaces the above with code similar to what the server side
of the krpc does for TCP, where it does a soreceive() for as much data
as possible and then parses RPC messages out of the received data.
A new field of the TCP socket structure called ct_raw is the list of
received mbufs that the RPC message(s) are parsed from.
I think this results in cleaner code and is needed for support of
nfs-over-tls.
It also fixes the code for the case where a server sends an RPC message
in multiple RPC message fragments. Although this is allowed by RFC5531,
no extant NFS server does this. However, it is probably good to fix this
in case some future NFS server does do this.
this type, but since RPC depends on XDR (not vice versa) we need
it defined in XDR to make the module loadable without RPC.
Reviewed by: rmacklem
Differential Revision: https://reviews.freebsd.org/D24408
Without this patch, the xid used for the client side krpc requests over
UDP was initialized for each "connection". A "connection" for UDP is
rather sketchy and for the kernel NLM a new one is created every 2minutes.
A problem with client side interoperability with a Netapp server for the NLM
was reported and it is believed to be caused by reuse of the same xid.
Although this was never completely diagnosed by the reporter, I could see
how the same xid might get reused, since it is initialized to a value
based on the TOD clock every two minutes.
I suspect initializing the value for every "connection" was inherited from
userland library code, where having a global xid was not practical.
However, implementing a global "xid" for the kernel rpc is straightforward
and will ensure that an xid value is not reused for a long time. This
patch does that and is hoped it will fix the Netapp interoperability
problem.
PR: 245022
Reported by: danny@cs.huji.ac.il
MFC after: 2 weeks
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.
This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.
Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT
Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718
The kernel RPCSEC_GSS code sets the credential (called a client) lifetime
to the lifetime of the Kerberos ticket, which is typically several hours.
As such, when a user's credentials change such as being added to a new group,
it can take several hours for this change to be recognized by the NFS server.
This patch adds a sysctl called kern.rpc.gss.lifetime_max which can be set
by a sysadmin to put a cap on the time to expire for the credentials, so that
a sysadmin can reduce the timeout.
It also fixes a bug, where time_uptime is added twice when GSS_C_INDEFINITE
is returned for a lifetime. This has no effect in practice, sine Kerberos
never does this.
Tested by: pen@lysator.liu.se
PR: 242132
Submitted by: pen@lysator.liu.se
MFC after: 2 weeks
The code enabled when "DEBUG" is defined uses mem_alloc(), which is a
malloc(.., M_RPC, M_WAITOK | M_ZERO), but then calls gss_release_buffer()
which does a free(.., M_GSSAPI) to free the memory.
This patch fixes the problem by replacing mem_alloc() with a
malloc(.., M_GSSAPI, M_WAITOK | M_ZERO).
This bug affects almost no one, since the sources are not normally built
with "DEBUG" defined.
Submitted by: peter@ifm.liu.se
MFC after: 2 weeks
When a new client structure was allocated, it was added to the list
so that it was visible to other threads before the expiry time was
initialized, with only a single reference count.
The caller would increment the reference count, but it was possible
for another thread to decrement the reference count to zero and free
the structure before the caller incremented the reference count.
This could occur because the expiry time was still set to zero when
the new client structure was inserted in the list and the list was
unlocked.
This patch fixes the race by initializing the reference count to two
and initializing all fields, including the expiry time, before inserting
it in the list.
Tested by: peter@ifm.liu.se
PR: 235582
MFC after: 2 weeks
The old value resulted in bad performance, with high kernel
and gssd(8) load, with more than ~64 clients; it also triggered
crashes, which are to be fixed by a different patch.
PR: 235582
Discussed with: rmacklem@
MFC after: 2 weeks
it easily. This can lower the load on gssd(8) on large NFS servers.
Submitted by: Per Andersson <pa at chalmers dot se>
Reviewed by: rmacklem@
MFC after: 2 weeks
Sponsored by: Chalmers University of Technology
This can drastically lower the load on gssd(8) on large NFS servers.
Submitted by: Per Andersson <pa at chalmers dot se>
Reviewed by: rmacklem@
MFC after: 2 weeks
Sponsored by: Chalmers University of Technology
Differential Revision: https://reviews.freebsd.org/D18393
During testing of the pNFS client, it was observed that an RPC could get
stuck in sosend() for a very long time if the network connection to a DS
had failed. This is fixed by setting SO_SNDTIMEO on the TCP socket.
This is only done when CLSET_TIMEOUT is done and this is not done by any
use of the krpc currently in the source tree, so there should be no effect
on extant uses.
A future patch will use CLSET_TIMEOUT for TCP connections to DSs.
Reviewed by: kib
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D16293
Occationally the kernel nfsd threads would not terminate when a SIGKILL
was posted for the kernel process (called nfsd (slave)). When this occurred,
the thread associated with the process (called "ismaster") had returned from
svc_run_internal() and was sleeping waiting for the other threads to terminate.
The other threads (created by kthread_start()) were still in svc_run_internal()
handling NFS RPCs.
The only way this could occur is for the "ismaster" thread to return from
svc_run_internal() without having called svc_exit().
There was only one place in the code where this could happen and this patch
stops that from happening.
Since the problem is intermittent, I cannot be sure if this has fixed the
problem, but I have not seen an occurrence of the problem with this patch
applied.
Reviewed by: kib
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D16087
This reduces noise when kernel is compiled by newer GCC versions,
such as one used by external toolchain ports.
Reviewed by: kib, andrew(sys/arm and sys/arm64), emaste(partial), erj(partial)
Reviewed by: jhb (sys/dev/pci/* sys/kern/vfs_aio.c and sys/kern/kern_synch.c)
Differential Revision: https://reviews.freebsd.org/D10385
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
No functional change intended.
Mainly focus on files that use BSD 3-Clause license.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
o Separate fields of struct socket that belong to listening from
fields that belong to normal dataflow, and unionize them. This
shrinks the structure a bit.
- Take out selinfo's from the socket buffers into the socket. The
first reason is to support braindamaged scenario when a socket is
added to kevent(2) and then listen(2) is cast on it. The second
reason is that there is future plan to make socket buffers pluggable,
so that for a dataflow socket a socket buffer can be changed, and
in this case we also want to keep same selinfos through the lifetime
of a socket.
- Remove struct struct so_accf. Since now listening stuff no longer
affects struct socket size, just move its fields into listening part
of the union.
- Provide sol_upcall field and enforce that so_upcall_set() may be called
only on a dataflow socket, which has buffers, and for listening sockets
provide solisten_upcall_set().
o Remove ACCEPT_LOCK() global.
- Add a mutex to socket, to be used instead of socket buffer lock to lock
fields of struct socket that don't belong to a socket buffer.
- Allow to acquire two socket locks, but the first one must belong to a
listening socket.
- Make soref()/sorele() to use atomic(9). This allows in some situations
to do soref() without owning socket lock. There is place for improvement
here, it is possible to make sorele() also to lock optionally.
- Most protocols aren't touched by this change, except UNIX local sockets.
See below for more information.
o Reduce copy-and-paste in kernel modules that accept connections from
listening sockets: provide function solisten_dequeue(), and use it in
the following modules: ctl(4), iscsi(4), ng_btsocket(4), ng_ksocket(4),
infiniband, rpc.
o UNIX local sockets.
- Removal of ACCEPT_LOCK() global uncovered several races in the UNIX
local sockets. Most races exist around spawning a new socket, when we
are connecting to a local listening socket. To cover them, we need to
hold locks on both PCBs when spawning a third one. This means holding
them across sonewconn(). This creates a LOR between pcb locks and
unp_list_lock.
- To fix the new LOR, abandon the global unp_list_lock in favor of global
unp_link_lock. Indeed, separating these two locks didn't provide us any
extra parralelism in the UNIX sockets.
- Now call into uipc_attach() may happen with unp_link_lock hold if, we
are accepting, or without unp_link_lock in case if we are just creating
a socket.
- Another problem in UNIX sockets is that uipc_close() basicly did nothing
for a listening socket. The vnode remained opened for connections. This
is fixed by removing vnode in uipc_close(). Maybe the right way would be
to do it for all sockets (not only listening), simply move the vnode
teardown from uipc_detach() to uipc_close()?
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D9770
A long long time ago the register keyword told the compiler to store
the corresponding variable in a CPU register, but it is not relevant
for any compiler used in the FreeBSD world today.
ANSIfy related prototypes while here.
Reviewed by: cem, jhb
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D10193
When sosend() replies ERESTART in the client side krpc, it indicates that
the RPC message hasn't yet been sent and that the send queue is full or
locked while a signal is posted for the process.
Without this patch, this would result in a RPC_CANTSEND reply from
clnt_vc_call(), which would cause clnt_reconnect_call() to create a new
TCP transport connection. For most NFS servers, this wasn't a serious problem,
although it did imply retries of outstanding RPCs, which could possibly
have missed the DRC.
For an NFSv4.1 mount to AmazonEFS, this caused a serious problem, since
AmazonEFS often didn't retain the NFSv4.1 session and would reply with
NFS4ERR_BAD_SESSION. This implies to the client a crash/reboot which
requires open/lock state recovery.
Three options were considered to fix this:
- Return the ERESTART all the way up to the system call boundary and then
have the system call redone. This is fraught with risk, due to convoluted
code paths, asynchronous I/O RPCs etc. cperciva@ worked on this, but it
is still a work in prgress and may not be feasible.
- Set SB_NOINTR for the socket buffer. This fixes the problem, but makes
the sosend() completely non interruptible, which kib@ considered
inappropriate. It also would break forced dismount when a thread
was blocked in sosend().
- Modify the retry loop in clnt_vc_call(), so that it loops for this case
for up to 15sec. Testing showed that the sosend() usually succeeded by
the 2nd retry. The extreme case observed was 111 loop iterations, or
about 100msec of delay.
This third alternative is what is implemented in this patch, since the
change is:
- localized
- straightforward
- forced dismount is not broken by it.
This patch has been tested by cperciva@ extensively against AmazonEFS.
Reported by: cperciva
Tested by: cperciva
MFC after: 2 weeks
Larry Rosenman reported a crash on freebsd-current@ which was caused by
a premature release of the krpc backchannel socket structure.
I believe this was caused by a race between the SVC_RELEASE() in clnt_vc.c
and the xprt_unregister() in the higher layer (clnt_rc.c), which tried
to lock the mutex in the xprt structure and crashed.
This patch fixes this by removing the xprt_unregister() in the clnt_vc
layer and allowing this to always be done by the clnt_rc (higher reconnect
layer).
Reported by: ler@lerctr.org
Tested by: ler@letctr.org
MFC after: 2 weeks
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.
Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96
This patch adds a new function to the server krpc called
svcpool_close(). It is similar to svcpool_destroy(), but does not free
the data structures, so that the pool can be used again.
This function is then used instead of svcpool_destroy(),
svcpool_create() when the nfsd threads are killed.
PR: 204340
Reported by: Panzura
Approved by: rmacklem
Obtained from: rmacklem
MFC after: 1 week
and getboottimebin(9) KPI. Change consumers of boottime to use the
KPI. The variables were renamed to avoid shadowing issues with local
variables of the same name.
Issue is that boottime* should be adjusted from tc_windup(), which
requires them to be members of the timehands structure. As a
preparation, this commit only introduces the interface.
Some uses of boottime were found doubtful, e.g. NLM uses boottime to
identify the system boot instance. Arguably the identity should not
change on the leap second adjustment, but the commit is about the
timekeeping code and the consumers were kept bug-to-bug compatible.
Tested by: pho (as part of the bigger patch)
Reviewed by: jhb (same)
Discussed with: bde
Sponsored by: The FreeBSD Foundation
MFC after: 1 month
X-Differential revision: https://reviews.freebsd.org/D7302
Similar to r300836, r301800, and r302550, cl and ct will always
be non-NULL as they're allocated using the mem_alloc routines,
which always use `malloc(..., M_WAITOK)`.
MFC after: 1 week
Reported by: Coverity
CID: 1007342
Sponsored by: EMC / Isilon Storage Division
Similar to r300836 and r301800, cl and cu will always be non-NULL as they're
allocated using the mem_alloc routines, which always use
`malloc(..., M_WAITOK)`.
Deobfuscating the cleanup path fixes a leak where if cl was NULL and
cu was not, cu would not be free'd, and also removes a duplicate test for
cl not being NULL.
MFC after: 1 week
Reported by: Coverity
CID: 1007033, 1007344
Sponsored by: EMC / Isilon Storage Division
Similar to r300836, cl and ct will always be non-NULL as they're allocated
using the mem_alloc routines, which always use `malloc(..., M_WAITOK)`.
Deobfuscating the cleanup path fixes a leak where if cl was NULL and
ct was not, ct would not be free'd, and also removes a duplicate test for
cl not being NULL.
Approved by: re (gjb)
Differential Revision: https://reviews.freebsd.org/D6801
MFC after: 1 week
Reported by: Coverity
CID: 1229999
Reviewed by: cem
Sponsored by: EMC / Isilon Storage Division
Both cd and xprt will be non-NULL after their respective malloc(9) wrappers are
called (mem_alloc and svc_xprt_alloc, which calls mem_alloc) as mem_alloc
always gets called with M_WAITOK|M_ZERO today. Thus, testing for them being
non-NULL is incorrect -- it misleads Coverity and it misleads the reader.
Remove some unnecessary NULL initializations as a follow up to help solidify
the fact that these pointers will be initialized properly in sys/rpc/.. with
the interfaces the way they are currently.
Differential Revision: https://reviews.freebsd.org/D6572
MFC after: 2 weeks
Reported by: Coverity
CID: 1007338, 1007339, 1007340
Reviewed by: markj, truckman
Sponsored by: EMC / Isilon Storage Division
The mem_alloc macro calls calloc (userspace) / malloc(.., M_WAITOK|M_ZERO)
under the covers, so zeroing out memory is already handled by the underlying
calls
MFC after: 1 week
Sponsored by: EMC / Isilon Storage Division
'buf.value' was previously treated as a nul-terminated string, but only
allocated with strlen() space. Rectify this.
Reported by: Coverity
CID: 1007639
Sponsored by: EMC / Isilon Storage Division
