[ Upstream commit 64e6304169f1e1f078e7f0798033f80a7fb0ea46 ]
It's not safe to call nfsd_put once nfsd_last_thread has been called, as
that function will zero out the nn->nfsd_serv pointer.
Drop the nfsd_put helper altogether and open-code the svc_put in its
callers instead. That allows us to not be reliant on the value of that
pointer when handling an error.
Fixes: 2a501f55cd64 ("nfsd: call nfsd_last_thread() before final nfsd_put()")
Reported-by: Zhi Li <yieli@redhat.com>
Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Jeffrey Layton <jlayton@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2a501f55cd641eb4d3c16a2eab0d678693fac663 ]
If write_ports_addfd or write_ports_addxprt fail, they call nfsd_put()
without calling nfsd_last_thread(). This leaves nn->nfsd_serv pointing
to a structure that has been freed.
So remove 'static' from nfsd_last_thread() and call it when the
nfsd_serv is about to be destroyed.
Fixes: ec52361df99b ("SUNRPC: stop using ->sv_nrthreads as a refcount")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c034203b6a9dae6751ef4371c18cb77983e30c28 ]
The bug here is that you cannot rely on getting the same socket
from multiple calls to fget() because userspace can influence
that. This is a kind of double fetch bug.
The fix is to delete the svc_alien_sock() function and instead do
the checking inside the svc_addsock() function.
Fixes: 3064639423c4 ("nfsd: check passed socket's net matches NFSd superblock's one")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f385f7d244134246f984975ed34cd75f77de479f ]
Currently the nfsd-client shrinker is registered and unregistered at
the time the nfsd module is loaded and unloaded. The problem with this
is the shrinker is being registered before all of the relevant fields
in nfsd_net are initialized when nfsd is started. This can lead to an
oops when memory is low and the shrinker is called while nfsd is not
running.
This patch moves the register/unregister of nfsd-client shrinker from
module load/unload time to nfsd startup/shutdown time.
Fixes: 44df6f439a17 ("NFSD: add delegation reaper to react to low memory condition")
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
[ cel: adjusted to apply without e33c267ab70d ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2f3a4b2ac2f28b9be78ad21f401f31e263845214 ]
rpc.nfsd stopped supporting NFSv2 a year ago. Take the next logical
step toward deprecating it and allow NFSv2 support to be compiled out.
Add a new CONFIG_NFSD_V2 option that can be turned off and rework the
CONFIG_NFSD_V?_ACL option dependencies. Add a description that
discourages enabling it.
Also, change the description of CONFIG_NFSD to state that the always-on
version is now 3 instead of 2.
Finally, add an #ifdef around "case 2:" in __write_versions. When NFSv2
is disabled at compile time, this should make the kernel ignore attempts
to disable it at runtime, but still error out when trying to enable it.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8e823bafff2308753d430566256c83d8085952da ]
The kernel currently errors out if you attempt to enable or disable a
version that it doesn't recognize. Change it to ignore attempts to
disable an unrecognized version. If we don't support it, then there is
no harm in doing so.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bd86c69dae65de30f6d47249418ba7889809e31a ]
syzbot is reporting UAF read at register_shrinker_prepared() [1], for
commit 7746b32f467b3813 ("NFSD: add shrinker to reap courtesy clients on
low memory condition") missed that nfsd4_leases_net_shutdown() from
nfsd_exit_net() is called only when nfsd_init_net() succeeded.
If nfsd_init_net() fails due to nfsd_reply_cache_init() failure,
register_shrinker() from nfsd4_init_leases_net() has to be undone
before nfsd_init_net() returns.
Link: https://syzkaller.appspot.com/bug?extid=ff796f04613b4c84ad89 [1]
Reported-by: syzbot <syzbot+ff796f04613b4c84ad89@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: 7746b32f467b3813 ("NFSD: add shrinker to reap courtesy clients on low memory condition")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 64776611a06322b99386f8dfe3b3ba1aa0347a38 ]
Use DEFINE_SHOW_ATTRIBUTE helper macro to simplify the code.
nfsd_net is converted from seq_file->file instead of seq_file->private in
nfsd_reply_cache_stats_show().
Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
[ cel: reduce line length ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7746b32f467b3813fb61faaab3258de35806a7ac ]
Add courtesy_client_reaper to react to low memory condition triggered
by the system memory shrinker.
The delayed_work for the courtesy_client_reaper is scheduled on
the shrinker's count callback using the laundry_wq.
The shrinker's scan callback is not used for expiring the courtesy
clients due to potential deadlocks.
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
[ cel: adjusted to apply without e33c267ab70d ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3a5940bfa17fb9964bf9688b4356ca643a8f5e2d ]
This printk pops every time nfsd.ko gets plugged in. Most kmods don't do
that and this one is not very informative. Olaf's email address seems to
be defunct at this point anyway. Just drop it.
Cc: Olaf Kirch <okir@suse.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6867137ebcf4155fe25f2ecf7c29b9fb90a76d1d ]
This patch moves the v4 specific code from nfsd_init_net() to
nfsd4_init_leases_net() helper in nfs4state.c
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2e6c6e4c4375bfd3defa5b1ff3604d9f33d1c936 ]
There has always been the capability of exporting filecache metrics
via /proc, but it was never hooked up. Let's surface these metrics
to enable better observability of the filecache.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 842e00ac3aa3b4a4f7f750c8ab54f8578fc875d3 ]
Variable len is being assigned a value zero and this is never
read, it is being re-assigned later. The assignment is redundant
and can be removed.
Cleans up clang scan-build warning:
fs/nfsd/nfsctl.c:636:2: warning: Value stored to 'len' is never read
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6f6f84aa215f7b6665ccbb937db50860f9ec2989 ]
KASAN report null-ptr-deref as follows:
BUG: KASAN: null-ptr-deref in nfsd_fill_super+0xc6/0xe0 [nfsd]
Write of size 8 at addr 000000000000005d by task a.out/852
CPU: 7 PID: 852 Comm: a.out Not tainted 5.18.0-rc7-dirty #66
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x34/0x44
kasan_report+0xab/0x120
? nfsd_mkdir+0x71/0x1c0 [nfsd]
? nfsd_fill_super+0xc6/0xe0 [nfsd]
nfsd_fill_super+0xc6/0xe0 [nfsd]
? nfsd_mkdir+0x1c0/0x1c0 [nfsd]
get_tree_keyed+0x8e/0x100
vfs_get_tree+0x41/0xf0
__do_sys_fsconfig+0x590/0x670
? fscontext_read+0x180/0x180
? anon_inode_getfd+0x4f/0x70
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
This can be reproduce by concurrent operations:
1. fsopen(nfsd)/fsconfig
2. insmod/rmmod nfsd
Since the nfsd file system is registered before than nfsd_net allocated,
the caller may get the file_system_type and use the nfsd_net before it
allocated, then null-ptr-deref occurred.
So init_nfsd() should call register_filesystem() last.
Fixes: bd5ae9288d64 ("nfsd: register pernet ops last, unregister first")
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d76cc46b37e123e8d245cc3490978dbda56f979d ]
This patch moves create/destroy of laundry_wq from nfs4_state_start
and nfs4_state_shutdown_net to init_nfsd and exit_nfsd to prevent
the laundromat from being freed while a thread is processing a
conflicting lock.
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4355d767a21b9445958fc11bce9a9701f76529d3 ]
Clean up: Use the "svc_xprt_<task>" function naming convention as
is used for other external APIs.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 352ad31448fecc78a2e9b78da64eea5d63b8d0ce ]
Clean up: Use the "svc_xprt_<task>" function naming convention as
is used for other external APIs.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 91d2e9b56cf5c80f9efc530d494968369a8a0e0d ]
There are two boot-time fields in struct nfsd_net: one called
boot_time and one called nfssvc_boot. The latter is used only to
form write verifiers, but its documenting comment declares:
/* Time of server startup */
Since commit 27c438f53e79 ("nfsd: Support the server resetting the
boot verifier"), this field can be reset at any time; it's no
longer tied to server restart. So that comment is stale.
Also, according to pahole, struct timespec64 is 16 bytes long on
x86_64. The nfssvc_boot field is used only to form a write verifier,
which is 8 bytes long.
Let's clarify this situation by manufacturing an 8-byte verifier
in nfs_reset_boot_verifier() and storing only that in struct
nfsd_net.
We're grabbing 128 bits of time, so compress all of those into a
64-bit verifier instead of throwing out the high-order bits.
In the future, the siphash_key can be re-used for other hashed
objects per-nfsd_net.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d057cfec4940ce6eeffa22b4a71dec203b06cd55 ]
nfsd currently maintains an open-coded read/write semaphore (refcount
and wait queue) for each network namespace to ensure the nfs service
isn't shut down while the notifier is running.
This is excessive. As there is unlikely to be contention between
notifiers and they run without sleeping, a single spinlock is sufficient
to avoid problems.
Signed-off-by: NeilBrown <neilb@suse.de>
[ cel: ensure nfsd_notifier_lock is static ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ec52361df99b490f6af412b046df9799b92c1050 ]
The use of sv_nrthreads as a general refcount results in clumsy code, as
is seen by various comments needed to explain the situation.
This patch introduces a 'struct kref' and uses that for reference
counting, leaving sv_nrthreads to be a pure count of threads. The kref
is managed particularly in svc_get() and svc_put(), and also nfsd_put();
svc_destroy() now takes a pointer to the embedded kref, rather than to
the serv.
nfsd allows the svc_serv to exist with ->sv_nrhtreads being zero. This
happens when a transport is created before the first thread is started.
To support this, a 'keep_active' flag is introduced which holds a ref on
the svc_serv. This is set when any listening socket is successfully
added (unless there are running threads), and cleared when the number of
threads is set. So when the last thread exits, the nfs_serv will be
destroyed.
The use of 'keep_active' replaces previous code which checked if there
were any permanent sockets.
We no longer clear ->rq_server when nfsd() exits. This was done
to prevent svc_exit_thread() from calling svc_destroy().
Instead we take an extra reference to the svc_serv to prevent
svc_destroy() from being called.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8c62d12740a1450d2e8456d5747f440e10db281a ]
svc_destroy() is poorly named - it doesn't necessarily destroy the svc,
it might just reduce the ref count.
nfsd_destroy() is poorly named for the same reason.
This patch:
- removes the refcount functionality from svc_destroy(), moving it to
a new svc_put(). Almost all previous callers of svc_destroy() now
call svc_put().
- renames nfsd_destroy() to nfsd_put() and improves the code, using
the new svc_destroy() rather than svc_put()
- removes a few comments that explain the important for balanced
get/put calls. This should be obvious.
The only non-trivial part of this is that svc_destroy() would call
svc_sock_update() on a non-final decrement. It can no longer do that,
and svc_put() isn't really a good place of it. This call is now made
from svc_exit_thread() which seems like a good place. This makes the
call *before* sv_nrthreads is decremented rather than after. This
is not particularly important as the call just sets a flag which
causes sv_nrthreads set be checked later. A subsequent patch will
improve the ordering.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 89b24336f03a8ba560e96b0c47a8434a7fa48e3c ]
If write_ports_add() fails, we shouldn't destroy the serv, unless we had
only just created it. So if there are any permanent sockets already
attached, leave the serv in place.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 76c50eb70d8e1133eaada0013845619c36345fbc ]
In preparation to enable -Wimplicit-fallthrough for Clang, fix multiple
warnings by explicitly adding a couple of break statements instead of
just letting the code fall through to the next case.
Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 472d155a0631bd1a09b5c0c275a254e65605d683 ]
mountd can now monitor clients appearing and disappearing in
/proc/fs/nfsd/clients, and will log these events, in liu of the logging
of mount/unmount events for NFSv3.
Currently it cannot distinguish between unconfirmed clients (which might
be transient and totally uninteresting) and confirmed clients.
So add a "status: " line which reports either "confirmed" or
"unconfirmed", and use fsnotify to report that the info file
has been modified.
This requires a bit of infrastructure to keep the dentry for the "info"
file. There is no need to take a counted reference as the dentry must
remain around until the client is removed.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 20ad856e47323e208ae8d6a9ecfe5bf0be6f505e ]
Collect some nfsd stats per export in addition to the global stats.
A new nfsdfs export_stats file is created. It uses the same ops as the
exports file to iterate the export entries and we use the file's name to
determine the reported info per export. For example:
$ cat /proc/fs/nfsd/export_stats
# Version 1.1
# Path Client Start-time
# Stats
/test localhost 92
fh_stale: 0
io_read: 9
io_write: 1
Every export entry reports the start time when stats collection
started, so stats collecting scripts can know if stats where reset
between samples.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e567b98ce9a4b35b63c364d24828a9e5cd7a8179 ]
nfsd stats counters can be updated by concurrent nfsd threads without any
protection.
Convert some nfsd_stats and nfsd_net struct members to use percpu counters.
The longest_chain* members of struct nfsd_net remain unprotected.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
