commit 6e73e92b155c868ff7fce9d108839668caf1d9be upstream.
When running an nfs stress test, I see quite a few cached replies that
don't match up with the actual request. The first comment in
replay_matches_cache() makes sense, but the code doesn't seem to
match... fix it.
This isn't exactly a bugfix, as the server isn't required to catch every
case of a false retry. So, we may as well do this, but if this is
fixing a problem then that suggests there's a client bug.
Fixes: 53da6a53e1d4 ("nfsd4: catch some false session retries")
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 255fbca65137e25b12bced18ec9a014dc77ecda0 ]
As the man(2) page for utime/utimes states, EPERM is returned when the
second parameter of utime or utimes is not NULL, the caller's effective UID
does not match the owner of the file, and the caller is not privileged.
However, in a NFS directory mounted from knfsd, it will return EACCES
(from nfsd_setattr-> fh_verify->nfsd_permission). This patch fixes
that.
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b493fd31c0b89d9453917e977002de58bebc3802 ]
__cld_pipe_upcall() emits a "do not call blocking ops when
!TASK_RUNNING" warning due to the dput() call in rpc_queue_upcall().
Fix it by using a completion instead of hand coding the wait.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3b2d4dcf71c4a91b420f835e52ddea8192300a3b ]
Since commit 10a68cdf10 (nfsd: fix performance-limiting session
calculation) (Linux 5.1-rc1 and 4.19.31), shares from NFS servers with
1 TB of memory cannot be mounted anymore. The mount just hangs on the
client.
The gist of commit 10a68cdf10 is the change below.
-avail = clamp_t(int, avail, slotsize, avail/3);
+avail = clamp_t(int, avail, slotsize, total_avail/3);
Here are the macros.
#define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <)
#define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi)
`total_avail` is 8,434,659,328 on the 1 TB machine. `clamp_t()` casts
the values to `int`, which for 32-bit integers can only hold values
−2,147,483,648 (−2^31) through 2,147,483,647 (2^31 − 1).
`avail` (in the function signature) is just 65536, so that no overflow
was happening. Before the commit the assignment would result in 21845,
and `num = 4`.
When using `total_avail`, it is causing the assignment to be
18446744072226137429 (printed as %lu), and `num` is then 4164608182.
My next guess is, that `nfsd_drc_mem_used` is then exceeded, and the
server thinks there is no memory available any more for this client.
Updating the arguments of `clamp_t()` and `min_t()` to `unsigned long`
fixes the issue.
Now, `avail = 65536` (before commit 10a68cdf10 `avail = 21845`), but
`num = 4` remains the same.
Fixes: c54f24e338ed (nfsd: fix performance-limiting session calculation)
Cc: stable@vger.kernel.org
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c54f24e338ed2a35218f117a4a1afb5f9e2b4e64 ]
We're unintentionally limiting the number of slots per nfsv4.1 session
to 10. Often more than 10 simultaneous RPCs are needed for the best
performance.
This calculation was meant to prevent any one client from using up more
than a third of the limit we set for total memory use across all clients
and sessions. Instead, it's limiting the client to a third of the
maximum for a single session.
Fix this.
Reported-by: Chris Tracy <ctracy@engr.scu.edu>
Cc: stable@vger.kernel.org
Fixes: de766e570413 "nfsd: give out fewer session slots as limit approaches"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit de766e570413bd0484af0b580299b495ada625c3 ]
Instead of granting client's full requests until we hit our DRC size
limit and then failing CREATE_SESSIONs (and hence mounts) completely,
start granting clients smaller slot tables as we approach the limit.
The factor chosen here is pretty much arbitrary.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 44d8660d3bb0a1c8363ebcb906af2343ea8e15f6 ]
An NFSv4.1+ client negotiates the size of its duplicate reply cache size
in the initial CREATE_SESSION request. The server preallocates the
memory for the duplicate reply cache to ensure that we'll never fail to
record the response to a nonidempotent operation.
To prevent a few CREATE_SESSIONs from consuming all of memory we set an
upper limit based on nr_free_buffer_pages(). 1/2^10 has been too
limiting in practice; 1/2^7 is still less than one percent.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0b8f62625dc309651d0efcb6a6247c933acd8b45 ]
A fuzzer recently triggered lockdep warnings about potential sb_writers
deadlocks caused by fh_want_write().
Looks like we aren't careful to pair each fh_want_write() with an
fh_drop_write().
It's not normally a problem since fh_put() will call fh_drop_write() for
us. And was OK for NFSv3 where we'd do one operation that might call
fh_want_write(), and then put the filehandle.
But an NFSv4 protocol fuzzer can do weird things like call unlink twice
in a compound, and then we get into trouble.
I'm a little worried about this approach of just leaving everything to
fh_put(). But I think there are probably a lot of
fh_want_write()/fh_drop_write() imbalances so for now I think we need it
to be more forgiving.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e6abc8caa6deb14be2a206253f7e1c5e37e9515b upstream.
If there are multiple callbacks queued, waiting for the callback
slot when the callback gets shut down, then they all currently
end up acting as if they hold the slot, and call
nfsd4_cb_sequence_done() resulting in interesting side-effects.
In addition, the 'retry_nowait' path in nfsd4_cb_sequence_done()
causes a loop back to nfsd4_cb_prepare() without first freeing the
slot, which causes a deadlock when nfsd41_cb_get_slot() gets called
a second time.
This patch therefore adds a boolean to track whether or not the
callback did pick up the slot, so that it can do the right thing
in these 2 cases.
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dd838821f0a29781b185cd8fb8e48d5c177bd838 upstream.
Commit 62a063b8e7d1 "nfsd4: fix crash on writing v4_end_grace before
nfsd startup" is trying to fix a NULL dereference issue, but it
mistakenly checks if the nfsd server is started. So fix it.
Fixes: 62a063b8e7d1 "nfsd4: fix crash on writing v4_end_grace before nfsd startup"
Cc: stable@vger.kernel.org
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: Yihao Wu <wuyihao@linux.alibaba.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b602345da6cbb135ba68cf042df8ec9a73da7981 upstream.
If the result of an NFSv3 readdir{,plus} request results in the
"offset" on one entry having to be split across 2 pages, and is sized
so that the next directory entry doesn't fit in the requested size,
then memory corruption can happen.
When encode_entry() is called after encoding the last entry that fits,
it notices that ->offset and ->offset1 are set, and so stores the
offset value in the two pages as required. It clears ->offset1 but
*does not* clear ->offset.
Normally this omission doesn't matter as encode_entry_baggage() will
be called, and will set ->offset to a suitable value (not on a page
boundary).
But in the case where cd->buflen < elen and nfserr_toosmall is
returned, ->offset is not reset.
This means that nfsd3proc_readdirplus will see ->offset with a value 4
bytes before the end of a page, and ->offset1 set to NULL.
It will try to write 8bytes to ->offset.
If we are lucky, the next page will be read-only, and the system will
BUG: unable to handle kernel paging request at...
If we are unlucky, some innocent page will have the first 4 bytes
corrupted.
nfsd3proc_readdir() doesn't even check for ->offset1, it just blindly
writes 8 bytes to the offset wherever it is.
Fix this by clearing ->offset after it is used, and copying the
->offset handling code from nfsd3_proc_readdirplus into
nfsd3_proc_readdir.
(Note that the commit hash in the Fixes tag is from the 'history'
tree - this bug predates git).
Fixes: 0b1d57cf7654 ("[PATCH] kNFSd: Fix nfs3 dentry encoding")
Fixes-URL: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=0b1d57cf7654
Cc: stable@vger.kernel.org (v2.6.12+)
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 53da6a53e1d414e05759fa59b7032ee08f4e22d7 upstream.
The spec allows us to return NFS4ERR_SEQ_FALSE_RETRY if we notice that
the client is making a call that matches a previous (slot, seqid) pair
but that *isn't* actually a replay, because some detail of the call
doesn't actually match the previous one.
Catching every such case is difficult, but we may as well catch a few
easy ones. This also handles the case described in the previous patch,
in a different way.
The spec does however require us to catch the case where the difference
is in the rpc credentials. This prevents somebody from snooping another
user's replies by fabricating retries.
(But the practical value of the attack is limited by the fact that the
replies with the most sensitive data are READ replies, which are not
normally cached.)
Tested-by: Olga Kornievskaia <aglo@umich.edu>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Donald Buczek <buczek@molgen.mpg.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 085def3ade52f2ffe3e31f42e98c27dcc222dd37 upstream.
Currently our handling of 4.1+ requests without "cachethis" set is
confusing and not quite correct.
Suppose a client sends a compound consisting of only a single SEQUENCE
op, and it matches the seqid in a session slot (so it's a retry), but
the previous request with that seqid did not have "cachethis" set.
The obvious thing to do might be to return NFS4ERR_RETRY_UNCACHED_REP,
but the protocol only allows that to be returned on the op following the
SEQUENCE, and there is no such op in this case.
The protocol permits us to cache replies even if the client didn't ask
us to. And it's easy to do so in the case of solo SEQUENCE compounds.
So, when we get a solo SEQUENCE, we can either return the previously
cached reply or NFSERR_SEQ_FALSE_RETRY if we notice it differs in some
way from the original call.
Currently, we're returning a corrupt reply in the case a solo SEQUENCE
matches a previous compound with more ops. This actually matters
because the Linux client recently started doing this as a way to recover
from lost replies to idempotent operations in the case the process doing
the original reply was killed: in that case it's difficult to keep the
original arguments around to do a real retry, and the client no longer
cares what the result is anyway, but it would like to make sure that the
slot's sequence id has been incremented, and the solo SEQUENCE assures
that: if the server never got the original reply, it will increment the
sequence id. If it did get the original reply, it won't increment, and
nothing else that about the reply really matters much. But we can at
least attempt to return valid xdr!
Tested-by: Olga Kornievskaia <aglo@umich.edu>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Donald Buczek <buczek@molgen.mpg.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 62a063b8e7d1db684db3f207261a466fa3194e72 ]
Anatoly Trosinenko reports that this:
1) Checkout fresh master Linux branch (tested with commit e195ca6cb)
2) Copy x84_64-config-4.14 to .config, then enable NFS server v4 and build
3) From `kvm-xfstests shell`:
results in NULL dereference in locks_end_grace.
Check that nfsd has been started before trying to end the grace period.
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 01310bb7c9c98752cc763b36532fab028e0f8f81 upstream.
Make sure we have a saved filehandle, otherwise we'll oops with a null
pointer dereference in nfs4_preprocess_stateid_op().
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a725356b6659469d182d662f22d770d83d3bc7b5 upstream.
Commit 031a072a0b8a ("vfs: call vfs_clone_file_range() under freeze
protection") created a wrapper do_clone_file_range() around
vfs_clone_file_range() moving the freeze protection to former, so
overlayfs could call the latter.
The more common vfs practice is to call do_xxx helpers from vfs_xxx
helpers, where freeze protecction is taken in the vfs_xxx helper, so
this anomality could be a source of confusion.
It seems that commit 8ede205541ff ("ovl: add reflink/copyfile/dedup
support") may have fallen a victim to this confusion -
ovl_clone_file_range() calls the vfs_clone_file_range() helper in the
hope of getting freeze protection on upper fs, but in fact results in
overlayfs allowing to bypass upper fs freeze protection.
Swap the names of the two helpers to conform to common vfs practice
and call the correct helpers from overlayfs and nfsd.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 031a072a0b8a ("vfs: call vfs_clone_file_range() under freeze...")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5b7b15aee641904ae269be9846610a3950cbd64c ]
We're encoding a single op in the reply but leaving the number of ops
zero, so the reply makes no sense.
Somewhat academic as this isn't a case any real client will hit, though
in theory perhaps that could change in a future protocol extension.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3171822fdcdd6e6d536047c425af6dc7a92dc585 ]
When running a fuzz tester against a KASAN-enabled kernel, the following
splat periodically occurs.
The problem occurs when the test sends a GETDEVICEINFO request with a
malformed xdr array (size but no data) for gdia_notify_types and the
array size is > 0x3fffffff, which results in an overflow in the value of
nbytes which is passed to read_buf().
If the array size is 0x40000000, 0x80000000, or 0xc0000000, then after
the overflow occurs, the value of nbytes 0, and when that happens the
pointer returned by read_buf() points to the end of the xdr data (i.e.
argp->end) when really it should be returning NULL.
Fix this by returning NFS4ERR_BAD_XDR if the array size is > 1000 (this
value is arbitrary, but it's the same threshold used by
nfsd4_decode_bitmap()... in could really be any value >= 1 since it's
expected to get at most a single bitmap in gdia_notify_types).
[ 119.256854] ==================================================================
[ 119.257611] BUG: KASAN: use-after-free in nfsd4_decode_getdeviceinfo+0x5a4/0x5b0 [nfsd]
[ 119.258422] Read of size 4 at addr ffff880113ada000 by task nfsd/538
[ 119.259146] CPU: 0 PID: 538 Comm: nfsd Not tainted 4.17.0+ #1
[ 119.259662] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-1.fc25 04/01/2014
[ 119.261202] Call Trace:
[ 119.262265] dump_stack+0x71/0xab
[ 119.263371] print_address_description+0x6a/0x270
[ 119.264609] kasan_report+0x258/0x380
[ 119.265854] ? nfsd4_decode_getdeviceinfo+0x5a4/0x5b0 [nfsd]
[ 119.267291] nfsd4_decode_getdeviceinfo+0x5a4/0x5b0 [nfsd]
[ 119.268549] ? nfs4svc_decode_compoundargs+0xa5b/0x13c0 [nfsd]
[ 119.269873] ? nfsd4_decode_sequence+0x490/0x490 [nfsd]
[ 119.271095] nfs4svc_decode_compoundargs+0xa5b/0x13c0 [nfsd]
[ 119.272393] ? nfsd4_release_compoundargs+0x1b0/0x1b0 [nfsd]
[ 119.273658] nfsd_dispatch+0x183/0x850 [nfsd]
[ 119.274918] svc_process+0x161c/0x31a0 [sunrpc]
[ 119.276172] ? svc_printk+0x190/0x190 [sunrpc]
[ 119.277386] ? svc_xprt_release+0x451/0x680 [sunrpc]
[ 119.278622] nfsd+0x2b9/0x430 [nfsd]
[ 119.279771] ? nfsd_destroy+0x1c0/0x1c0 [nfsd]
[ 119.281157] kthread+0x2db/0x390
[ 119.282347] ? kthread_create_worker_on_cpu+0xc0/0xc0
[ 119.283756] ret_from_fork+0x35/0x40
[ 119.286041] Allocated by task 436:
[ 119.287525] kasan_kmalloc+0xa0/0xd0
[ 119.288685] kmem_cache_alloc+0xe9/0x1f0
[ 119.289900] get_empty_filp+0x7b/0x410
[ 119.291037] path_openat+0xca/0x4220
[ 119.292242] do_filp_open+0x182/0x280
[ 119.293411] do_sys_open+0x216/0x360
[ 119.294555] do_syscall_64+0xa0/0x2f0
[ 119.295721] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 119.298068] Freed by task 436:
[ 119.299271] __kasan_slab_free+0x130/0x180
[ 119.300557] kmem_cache_free+0x78/0x210
[ 119.301823] rcu_process_callbacks+0x35b/0xbd0
[ 119.303162] __do_softirq+0x192/0x5ea
[ 119.305443] The buggy address belongs to the object at ffff880113ada000
which belongs to the cache filp of size 256
[ 119.308556] The buggy address is located 0 bytes inside of
256-byte region [ffff880113ada000, ffff880113ada100)
[ 119.311376] The buggy address belongs to the page:
[ 119.312728] page:ffffea00044eb680 count:1 mapcount:0 mapping:0000000000000000 index:0xffff880113ada780
[ 119.314428] flags: 0x17ffe000000100(slab)
[ 119.315740] raw: 0017ffe000000100 0000000000000000 ffff880113ada780 00000001000c0001
[ 119.317379] raw: ffffea0004553c60 ffffea00045c11e0 ffff88011b167e00 0000000000000000
[ 119.319050] page dumped because: kasan: bad access detected
[ 119.321652] Memory state around the buggy address:
[ 119.322993] ffff880113ad9f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 119.324515] ffff880113ad9f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 119.326087] >ffff880113ada000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 119.327547] ^
[ 119.328730] ffff880113ada080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 119.330218] ffff880113ada100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
[ 119.331740] ==================================================================
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9c2ece6ef67e9d376f32823086169b489c422ed0 upstream.
nfsd4_readdir_rsize restricts rd_maxcount to svc_max_payload when
estimating the size of the readdir reply, but nfsd_encode_readdir
restricts it to INT_MAX when encoding the reply. This can result in log
messages like "kernel: RPC request reserved 32896 but used 1049444".
Restrict rd_dircount similarly (no reason it should be larger than
svc_max_payload).
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 880a3a5325489a143269a8e172e7563ebf9897bc upstream.
We're neglecting to clear the umask after it's set, which can cause a
later unrelated rpc to (incorrectly) use the same umask if it happens to
be processed by the same thread.
There's a more subtle problem here too:
An NFSv4 compound request is decoded all in one pass before any
operations are executed.
Currently we're setting current->fs->umask at the time we decode the
compound. In theory a single compound could contain multiple creates
each setting a umask. In that case we'd end up using whichever umask
was passed in the *last* operation as the umask for all the creates,
whether that was correct or not.
So, we should just be saving the umask at decode time and waiting to set
it until we actually process the corresponding operation.
In practice it's unlikely any client would do multiple creates in a
single compound. And even if it did they'd likely be from the same
process (hence carry the same umask). So this is a little academic, but
we should get it right anyway.
Fixes: 47057abde515 (nfsd: add support for the umask attribute)
Cc: stable@vger.kernel.org
Reported-by: Lucash Stach <l.stach@pengutronix.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 68ef3bc3166468678d5e1fdd216628c35bd1186f upstream.
We had some reports of panics in nfsd4_lm_notify, and that showed a
nfs4_lockowner that had outlived its so_client.
Ensure that we walk any leftover lockowners after tearing down all of
the stateids, and remove any blocked locks that they hold.
With this change, we also don't need to walk the nbl_lru on nfsd_net
shutdown, as that will happen naturally when we tear down the clients.
Fixes: 76d348fadff5 (nfsd: have nfsd4_lock use blocking locks for v4.1+ locks)
Reported-by: Frank Sorenson <fsorenso@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: stable@vger.kernel.org # 4.9
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 66282ec1cf004c09083c29cb5e49019037937bbd ]
Clients must be able to read a file in order to execute it, and for pNFS
that means the client needs to be able to perform a LAYOUTGET on the file.
This behavior for executable-only files was added for OPEN in commit
a043226bc140 "nfsd4: permit read opens of executable-only files".
This fixes up xfstests generic/126 on block/scsi layouts.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 81833de1a46edce9ca20cfe079872ac1c20ef359 ]
restart_grace() uses hardcoded init_net.
It can cause to "list_add double add" in following scenario:
1) nfsd and lockd was started in several net namespaces
2) nfsd in init_net was stopped (lockd was not stopped because
it have users from another net namespaces)
3) lockd got signal, called restart_grace() -> set_grace_period()
and enabled lock_manager in hardcoded init_net.
4) nfsd in init_net is started again,
its lockd_up() calls set_grace_period() and tries to add
lock_manager into init_net 2nd time.
Jeff Layton suggest:
"Make it safe to call locks_start_grace multiple times on the same
lock_manager. If it's already on the global grace_list, then don't try
to add it again. (But we don't intentionally add twice, so for now we
WARN about that case.)
With this change, we also need to ensure that the nfsd4 lock manager
initializes the list before we call locks_start_grace. While we're at
it, move the rest of the nfsd_net initialization into
nfs4_state_create_net. I see no reason to have it spread over two
functions like it is today."
Suggested patch was updated to generate warning in described situation.
Suggested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ae254dac721d44c0bfebe2795df87459e2e88219 ]
Prevent the use of the closed (invalid) special stateid by clients.
Signed-off-by: Andrew Elble <aweits@rit.edu>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9271d7e509c1bfc0b9a418caec29ec8d1ac38270 ]
After taking the stateid st_mutex, we want to know that the stateid
still represents valid state before performing any non-idempotent
actions.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1995266727fa8143897e89b55f5d3c79aa828420 upstream.
Commit bdcf0a423ea1 ("kernel: make groups_sort calling a responsibility
group_info allocators") appears to break nfsd rootsquash in a pretty
major way.
It adds a call to groups_sort() inside the loop that copies/squashes
gids, which means the valid gids are sorted along with the following
garbage. The net result is that the highest numbered valid gids are
replaced with any lower-valued garbage gids, possibly including 0.
We should sort only once, after filling in all the gids.
Fixes: bdcf0a423ea1 ("kernel: make groups_sort calling a responsibility ...")
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Wolfgang Walter <linux@stwm.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bdcf0a423ea1c40bbb40e7ee483b50fc8aa3d758 upstream.
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 <thiago.becker@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Acked-by: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 64ebe12494fd5d193f014ce38e1fd83cc57883c8 upstream.
From kernel 4.9, my two nfsv4 servers sometimes suffer from
"panic: unable to handle kernel page request"
in posix_unblock_lock() called from nfs4_laundromat().
These panics diseappear if we revert the commit "nfsd: add a LRU list
for blocked locks".
The cause appears to be a typo in nfs4_laundromat(), which is also
present in nfs4_state_shutdown_net().
Fixes: 7919d0a27f1e "nfsd: add a LRU list for blocked locks"
Cc: jlayton@redhat.com
Reveiwed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d8a1a000555ecd1b824ac1ed6df8fe364dfbbbb0 upstream.
If nfsd4_process_open2() is initialising a new stateid, and yet the
call to nfs4_get_vfs_file() fails for some reason, then we must
declare the stateid closed, and unhash it before dropping the mutex.
Right now, we unhash the stateid after dropping the mutex, and without
changing the stateid type, meaning that another OPEN could theoretically
look it up and attempt to use it.
Reported-by: Andrew W Elble <aweits@rit.edu>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 15ca08d3299682dc49bad73251677b2c5017ef08 upstream.
Open file stateids can linger on the nfs4_file list of stateids even
after they have been closed. In order to avoid reusing such a
stateid, and confusing the client, we need to recheck the
nfs4_stid's type after taking the mutex.
Otherwise, we risk reusing an old stateid that was already closed,
which will confuse clients that expect new stateids to conform to
RFC7530 Sections 9.1.4.2 and 16.2.5 or RFC5661 Sections 8.2.2 and 18.2.4.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 95da1b3a5aded124dd1bda1e3cdb876184813140 upstream.
If a delegation has been revoked by the server, operations using that
delegation should error out with NFS4ERR_DELEG_REVOKED in the >4.1
case, and NFS4ERR_BAD_STATEID otherwise.
The server needs NFSv4.1 clients to explicitly free revoked delegations.
If the server returns NFS4ERR_DELEG_REVOKED, the client will do that;
otherwise it may just forget about the delegation and be unable to
recover when it later sees SEQ4_STATUS_RECALLABLE_STATE_REVOKED set on a
SEQUENCE reply. That can cause the Linux 4.1 client to loop in its
stage manager.
Signed-off-by: Andrew Elble <aweits@rit.edu>
Reviewed-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 34b1744c91cc ("nfsd4: define ->op_release for compound ops")
defined a couple ->op_release functions and run them if necessary.
But there's a problem with that is that it reused
nfsd4_secinfo_release() as the op_release of OP_SECINFO_NO_NAME, and
caused a leak on struct nfsd4_secinfo_no_name in
nfsd4_encode_secinfo_no_name(), because there's no .si_exp field in
struct nfsd4_secinfo_no_name.
I found this because I was unable to umount an ext4 partition after
exporting it via NFS & run fsstress on the nfs mount. A simplified
reproducer would be:
# mount a local-fs device at /mnt/test, and export it via NFS with
# fsid=0 export option (this is required)
mount /dev/sda5 /mnt/test
echo "/mnt/test *(rw,no_root_squash,fsid=0)" >> /etc/exports
service nfs restart
# locally mount the nfs export with all default, note that I have
# nfsv4.1 configured as the default nfs version, because of the
# fsid export option, v4 mount would fail and fall back to v3
mount localhost:/mnt/test /mnt/nfs
# try to umount the underlying device, but got EBUSY
umount /mnt/nfs
service nfs stop
umount /mnt/test <=== EBUSY here
Fixed it by defining a separate nfsd4_secinfo_no_name_release()
function as the op_release method of OP_SECINFO_NO_NAME that
releases the correct nfsd4_secinfo_no_name structure.
Fixes: 34b1744c91cc ("nfsd4: define ->op_release for compound ops")
Signed-off-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
and a small cleanup to our xdr encoding.
-----BEGIN PGP SIGNATURE-----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=E3UQ
-----END PGP SIGNATURE-----
Merge tag 'nfsd-4.14' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"More RDMA work and some op-structure constification from Chuck Lever,
and a small cleanup to our xdr encoding"
* tag 'nfsd-4.14' of git://linux-nfs.org/~bfields/linux:
svcrdma: Estimate Send Queue depth properly
rdma core: Add rdma_rw_mr_payload()
svcrdma: Limit RQ depth
svcrdma: Populate tail iovec when receiving
nfsd: Incoming xdr_bufs may have content in tail buffer
svcrdma: Clean up svc_rdma_build_read_chunk()
sunrpc: Const-ify struct sv_serv_ops
nfsd: Const-ify NFSv4 encoding and decoding ops arrays
sunrpc: Const-ify instances of struct svc_xprt_ops
nfsd4: individual encoders no longer see error cases
nfsd4: skip encoder in trivial error cases
nfsd4: define ->op_release for compound ops
nfsd4: opdesc will be useful outside nfs4proc.c
nfsd4: move some nfsd4 op definitions to xdr4.h
Since the beginning, svcsock has built a received RPC Call message
by populating the xdr_buf's head, then placing the remaining
message bytes in the xdr_buf's page list. The xdr_buf's tail is
never populated.
This means that an NFSv4 COMPOUND containing an NFS WRITE operation
plus trailing operations has a page list that contains the WRITE
data payload followed by the trailing operations. NFSv4 XDR decoders
will not look in the xdr_buf's tail, ever, because svcsock never put
anything there.
To support transports that can pass the write payload in the
xdr_buf's pagelist and trailing content in the xdr_buf's tail,
introduce logic in READ_BUF that switches to the xdr_buf's tail vec
when the decoder runs out of content in rq_arg.pages.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Close an attack vector by moving the arrays of per-server methods to
read-only memory.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Close an attack vector by moving the arrays of encoding and decoding
methods to read-only memory.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Most encoders do nothing in the error case. But they can still screw
things up in that case: most errors happen very early in rpc processing,
possibly before argument fields are filled in and bounds-tested, so
encoders that do anything other than immediately bail on error can
easily crash in odd error cases.
So just handle errors centrally most of the time to remove the chance of
error.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Run a separate ->op_release function if necessary instead of depending
on the xdr encoder to do this.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When processing an NFSv4 WRITE operation, argp->end should never
point past the end of the data in the final page of the page list.
Otherwise, nfsd4_decode_compound can walk into uninitialized memory.
More critical, nfsd4_decode_write is failing to increment argp->pagelen
when it increments argp->pagelist. This can cause later xdr decoders
to assume more data is available than really is, which can cause server
crashes on malformed requests.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The offset of the entry in struct rpc_version has to match the version
number.
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Fixes: 1c5876ddbdb4 ("sunrpc: move p_count out of struct rpc_procinfo")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
RPC-over-RDMA transport to use the new rdma_rw API.
Christoph cleaned the way nfs operations are declared, removing a bunch
of function-pointer casts and declaring the operation vectors as const.
Christoph's changes touch both client and server, and both client and
server pulls this time around should be based on the same commits from
Christoph.
(Note: Anna and I initially didn't coordinate this well and we realized
our pull requests were going to leave you with Christoph's 33 patches
duplicated between our two trees. We decided a last-minute rebase was
the lesser of two evils, so her pull request will show that last-minute
rebase. Yell if that was the wrong choice, and we'll know better for
next time....)
-----BEGIN PGP SIGNATURE-----
iQIcBAABAgAGBQJZZ80JAAoJECebzXlCjuG+PiMP/jmw4IbzY4qt/X8aldVTMPZ8
TkEXuZSrc7FbmroqAR0XN/qJjzENKUcrnlYm7HKVe6iItTZUvJuVThtHQVGzZUZD
wP2VRzgkky59aDs9cphfTPGKPKL1MtoC3qQdFmKd/8ZhBDHIq89A2pQJwl7PI4rA
IHzvLmZtTKL+xWoypqZQxepONhEY2ZPrffGWL+5OVF/dPmWfJ6m/M6jRTb7zV/YD
PZyRqWQ8UY/HwZTwRrxZDCCxUsmRUPZz195iFjM8wvBl7auWNetC22gyyITlvfzf
1m0zJqw3qn09+v2xnAWs/ZVxypg6rsEiIcL2mf0JC/tQh+iIzabc4e/TwDEWqSq+
ocQrvXJuZCjsrMqg4oaIuDFogaZCsGR5wxDAEyfYDS/8fMdiKq8xJzT7v31/2U37
Bsr1hvgAmD4eZWaTrJg11V5RnTzDgns+EtNfISR8t4/k+wehDfyzav8A+j72sqvR
JT+7iUEd0QcBwo+MCC7AOnLLsIX45QUjZKKrvZNAC1fmr8RyAF1zo5HHO+NNjLuP
J2PUG2GbNxsQkm/JAFKDvyklLpEXZc6uyYAcEefirxYbh1x0GfuetzqtH58DtrQL
/1e80MRG9Qgq5S8PvYyvp1bIQPDRaQ188chEvzZy+3QeNXydq2LzDh0bjlM+4A9I
DZhP2pNGLh0ImaPtX0q+
=mR/a
-----END PGP SIGNATURE-----
Merge tag 'nfsd-4.13' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Chuck's RDMA update overhauls the "call receive" side of the
RPC-over-RDMA transport to use the new rdma_rw API.
Christoph cleaned the way nfs operations are declared, removing a
bunch of function-pointer casts and declaring the operation vectors as
const.
Christoph's changes touch both client and server, and both client and
server pulls this time around should be based on the same commits from
Christoph"
* tag 'nfsd-4.13' of git://linux-nfs.org/~bfields/linux: (53 commits)
svcrdma: fix an incorrect check on -E2BIG and -EINVAL
nfsd4: factor ctime into change attribute
svcrdma: Remove svc_rdma_chunk_ctxt::cc_dir field
svcrdma: use offset_in_page() macro
svcrdma: Clean up after converting svc_rdma_recvfrom to rdma_rw API
svcrdma: Clean-up svc_rdma_unmap_dma
svcrdma: Remove frmr cache
svcrdma: Remove unused Read completion handlers
svcrdma: Properly compute .len and .buflen for received RPC Calls
svcrdma: Use generic RDMA R/W API in RPC Call path
svcrdma: Add recvfrom helpers to svc_rdma_rw.c
sunrpc: Allocate up to RPCSVC_MAXPAGES per svc_rqst
svcrdma: Don't account for Receive queue "starvation"
svcrdma: Improve Reply chunk sanity checking
svcrdma: Improve Write chunk sanity checking
svcrdma: Improve Read chunk sanity checking
svcrdma: Remove svc_rdma_marshal.c
svcrdma: Avoid Send Queue overflow
svcrdma: Squelch disconnection messages
sunrpc: Disable splice for krb5i
...
Factoring ctime into the nfsv4 change attribute gives us better
properties than just i_version alone.
Eventually we'll likely also expose this (as opposed to raw i_version)
to userspace, at which point we'll want to move it to a common helper,
called from either userspace or individual filesystems. For now, nfsd
is the only user.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Pull read/write updates from Al Viro:
"Christoph's fs/read_write.c series - consolidation and cleanups"
* 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
nfsd: remove nfsd_vfs_read
nfsd: use vfs_iter_read/write
fs: implement vfs_iter_write using do_iter_write
fs: implement vfs_iter_read using do_iter_read
fs: move more code into do_iter_read/do_iter_write
fs: remove __do_readv_writev
fs: remove do_compat_readv_writev
fs: remove do_readv_writev
