2577 Commits

Author SHA1 Message Date
NeilBrown
520ccb81e3 nfsd: drop st_mutex before calling move_to_close_lru()
[ Upstream commit 56c35f43eef013579c76c007ba1f386d8c2cac14 ]

move_to_close_lru() is currently called with ->st_mutex held.
This can lead to a deadlock as move_to_close_lru() waits for sc_count to
drop to 2, and some threads holding a reference might be waiting for the
mutex.  These references will never be dropped so sc_count will never
reach 2.

There can be no harm in dropping ->st_mutex before
move_to_close_lru() because the only place that takes the mutex is
nfsd4_lock_ol_stateid(), and it quickly aborts if sc_type is
NFS4_CLOSED_STID, which it will be before move_to_close_lru() is called.

See also
 https://lore.kernel.org/lkml/4dd1fe21e11344e5969bb112e954affb@jd.com/T/
where this problem was raised but not successfully resolved.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 52d3370e8022ce28cd8cf4d16c09245aa683d7fb)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
2024-07-08 08:14:40 +00:00
Trond Myklebust
bdc1664459 nfsd: Remove incorrect check in nfsd4_validate_stateid
[ Upstream commit f75546f58a70da5cfdcec5a45ffc377885ccbee8 ]

If the client is calling TEST_STATEID, then it is because some event
occurred that requires it to check all the stateids for validity and
call FREE_STATEID on the ones that have been revoked. In this case,
either the stateid exists in the list of stateids associated with that
nfs4_client, in which case it should be tested, or it does not. There
are no additional conditions to be considered.

Reported-by: "Frank Ch. Eigler" <fche@redhat.com>
Fixes: 7df302f75ee2 ("NFSD: TEST_STATEID should not return NFS4ERR_STALE_STATEID")
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.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>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
2024-05-06 14:36:37 +00:00
J. Bruce Fields
70868b0c55 nfsd4: kill warnings on testing stateids with mismatched clientids
[ Upstream commit 663e36f07666ff924012defa521f88875f6e5402 ]

It's normal for a client to test a stateid from a previous instance,
e.g. after a network partition.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Stable-dep-of: f75546f58a70 ("nfsd: Remove incorrect check in nfsd4_validate_stateid")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
2024-05-06 14:36:37 +00:00
Greg Kroah-Hartman
1b29cdadfd Revert "NFSD: Fix possible sleep during nfsd4_release_lockowner()"
This reverts commit ef481b262bba4f454351eec43f024fec942c2d4c which is
commit ce3c4ad7f4ce5db7b4f08a1e237d8dd94b39180b upstream.

The maintainers ask it to be removed in this branch.

Cc: Dai Ngo <dai.ngo@oracle.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/linux-nfs/3162C5BC-8E7C-4A9A-815C-09297B56FA17@oracle.com/T/#t
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 10d75984495f7fe62152c3b0dbfa3f0a6b739c9b)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
2024-02-02 11:33:47 +00:00
Al Viro
9dd1c2431e nfsd: lock_rename() needs both directories to live on the same fs
commit 1aee9158bc978f91701c5992e395efbc6da2de3c upstream.

... checking that after lock_rename() is too late.  Incidentally,
NFSv2 had no nfserr_xdev...

Fixes: aa387d6ce153 "nfsd: fix EXDEV checking in rename"
Cc: stable@vger.kernel.org # v3.9+
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-08 11:21:07 +01:00
Jeff Layton
fc17bca3c0 nfsd: fix change_info in NFSv4 RENAME replies
commit fdd2630a7398191e84822612e589062063bd4f3d upstream.

nfsd sends the transposed directory change info in the RENAME reply. The
source directory is in save_fh and the target is in current_fh.

Reported-by: Zhi Li <yieli@redhat.com>
Reported-by: Benjamin Coddington <bcodding@redhat.com>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2218844
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-23 10:47:05 +02:00
Chuck Lever
82e36f0c28 NFSD: da_addr_body field missing in some GETDEVICEINFO replies
[ Upstream commit 6372e2ee629894433fe6107d7048536a3280a284 ]

The XDR specification in RFC 8881 looks like this:

struct device_addr4 {
	layouttype4	da_layout_type;
	opaque		da_addr_body<>;
};

struct GETDEVICEINFO4resok {
	device_addr4	gdir_device_addr;
	bitmap4		gdir_notification;
};

union GETDEVICEINFO4res switch (nfsstat4 gdir_status) {
case NFS4_OK:
	GETDEVICEINFO4resok gdir_resok4;
case NFS4ERR_TOOSMALL:
	count4		gdir_mincount;
default:
	void;
};

Looking at nfsd4_encode_getdeviceinfo() ....

When the client provides a zero gd_maxcount, then the Linux NFS
server implementation encodes the da_layout_type field and then
skips the da_addr_body field completely, proceeding directly to
encode gdir_notification field.

There does not appear to be an option in the specification to skip
encoding da_addr_body. Moreover, Section 18.40.3 says:

> If the client wants to just update or turn off notifications, it
> MAY send a GETDEVICEINFO operation with gdia_maxcount set to zero.
> In that event, if the device ID is valid, the reply's da_addr_body
> field of the gdir_device_addr field will be of zero length.

Since the layout drivers are responsible for encoding the
da_addr_body field, put this fix inside the ->encode_getdeviceinfo
methods.

Fixes: 9cf514ccfacb ("nfsd: implement pNFS operations")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Tom Haynes <loghyr@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-23 10:46:57 +02:00
Dai Ngo
dc77335b28 NFSD: add encoding of op_recall flag for write delegation
commit 58f5d894006d82ed7335e1c37182fbc5f08c2f51 upstream.

Modified nfsd4_encode_open to encode the op_recall flag properly
for OPEN result with write delegation granted.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11 11:33:41 +02:00
Kees Cook
d68627697d treewide: Remove uninitialized_var() usage
commit 3f649ab728cda8038259d8f14492fe400fbab911 upstream.

Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11 11:33:32 +02:00
Jeff Layton
dbf2a037bd nfsd: fix handling of readdir in v4root vs. mount upcall timeout
commit cad853374d85fe678d721512cecfabd7636e51f3 upstream.

If v4 READDIR operation hits a mountpoint and gets back an error,
then it will include that entry in the reply and set RDATTR_ERROR for it
to the error.

That's fine for "normal" exported filesystems, but on the v4root, we
need to be more careful to only expose the existence of dentries that
lead to exports.

If the mountd upcall times out while checking to see whether a
mountpoint on the v4root is exported, then we have no recourse other
than to fail the whole operation.

Cc: Steve Dickson <steved@redhat.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216777
Reported-by: JianHong Yin <yin-jianhong@163.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 09:26:41 +01:00
Dan Aloni
15fc60aa5b nfsd: under NFSv4.1, fix double svc_xprt_put on rpc_create failure
[ Upstream commit 3bc8edc98bd43540dbe648e4ef91f443d6d20a24 ]

On error situation `clp->cl_cb_conn.cb_xprt` should not be given
a reference to the xprt otherwise both client cleanup and the
error handling path of the caller call to put it. Better to
delay handing over the reference to a later branch.

[   72.530665] refcount_t: underflow; use-after-free.
[   72.531933] WARNING: CPU: 0 PID: 173 at lib/refcount.c:28 refcount_warn_saturate+0xcf/0x120
[   72.533075] Modules linked in: nfsd(OE) nfsv4(OE) nfsv3(OE) nfs(OE) lockd(OE) compat_nfs_ssc(OE) nfs_acl(OE) rpcsec_gss_krb5(OE) auth_rpcgss(OE) rpcrdma(OE) dns_resolver fscache netfs grace rdma_cm iw_cm ib_cm sunrpc(OE) mlx5_ib mlx5_core mlxfw pci_hyperv_intf ib_uverbs ib_core xt_MASQUERADE nf_conntrack_netlink nft_counter xt_addrtype nft_compat br_netfilter bridge stp llc nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set overlay nf_tables nfnetlink crct10dif_pclmul crc32_pclmul ghash_clmulni_intel xfs serio_raw virtio_net virtio_blk net_failover failover fuse [last unloaded: sunrpc]
[   72.540389] CPU: 0 PID: 173 Comm: kworker/u16:5 Tainted: G           OE     5.15.82-dan #1
[   72.541511] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.16.0-3.module+el8.7.0+1084+97b81f61 04/01/2014
[   72.542717] Workqueue: nfsd4_callbacks nfsd4_run_cb_work [nfsd]
[   72.543575] RIP: 0010:refcount_warn_saturate+0xcf/0x120
[   72.544299] Code: 55 00 0f 0b 5d e9 01 50 98 00 80 3d 75 9e 39 08 00 0f 85 74 ff ff ff 48 c7 c7 e8 d1 60 8e c6 05 61 9e 39 08 01 e8 f6 51 55 00 <0f> 0b 5d e9 d9 4f 98 00 80 3d 4b 9e 39 08 00 0f 85 4c ff ff ff 48
[   72.546666] RSP: 0018:ffffb3f841157cf0 EFLAGS: 00010286
[   72.547393] RAX: 0000000000000026 RBX: ffff89ac6231d478 RCX: 0000000000000000
[   72.548324] RDX: ffff89adb7c2c2c0 RSI: ffff89adb7c205c0 RDI: ffff89adb7c205c0
[   72.549271] RBP: ffffb3f841157cf0 R08: 0000000000000000 R09: c0000000ffefffff
[   72.550209] R10: 0000000000000001 R11: ffffb3f841157ad0 R12: ffff89ac6231d180
[   72.551142] R13: ffff89ac6231d478 R14: ffff89ac40c06180 R15: ffff89ac6231d4b0
[   72.552089] FS:  0000000000000000(0000) GS:ffff89adb7c00000(0000) knlGS:0000000000000000
[   72.553175] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   72.553934] CR2: 0000563a310506a8 CR3: 0000000109a66000 CR4: 0000000000350ef0
[   72.554874] Call Trace:
[   72.555278]  <TASK>
[   72.555614]  svc_xprt_put+0xaf/0xe0 [sunrpc]
[   72.556276]  nfsd4_process_cb_update.isra.11+0xb7/0x410 [nfsd]
[   72.557087]  ? update_load_avg+0x82/0x610
[   72.557652]  ? cpuacct_charge+0x60/0x70
[   72.558212]  ? dequeue_entity+0xdb/0x3e0
[   72.558765]  ? queued_spin_unlock+0x9/0x20
[   72.559358]  nfsd4_run_cb_work+0xfc/0x270 [nfsd]
[   72.560031]  process_one_work+0x1df/0x390
[   72.560600]  worker_thread+0x37/0x3b0
[   72.561644]  ? process_one_work+0x390/0x390
[   72.562247]  kthread+0x12f/0x150
[   72.562710]  ? set_kthread_struct+0x50/0x50
[   72.563309]  ret_from_fork+0x22/0x30
[   72.563818]  </TASK>
[   72.564189] ---[ end trace 031117b1c72ec616 ]---
[   72.566019] list_add corruption. next->prev should be prev (ffff89ac4977e538), but was ffff89ac4763e018. (next=ffff89ac4763e018).
[   72.567647] ------------[ cut here ]------------

Fixes: a4abc6b12eb1 ("nfsd: Fix svc_xprt refcnt leak when setup callback client failed")
Cc: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Cc: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Dan Aloni <dan.aloni@vastdata.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>
2023-01-18 09:26:28 +01:00
Anna Schumaker
38abf4a379 NFSD: Return nfserr_serverfault if splice_ok but buf->pages have data
[ Upstream commit 06981d560606ac48d61e5f4fff6738b925c93173 ]

This was discussed with Chuck as part of this patch set. Returning
nfserr_resource was decided to not be the best error message here, and
he suggested changing to nfserr_serverfault instead.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Link: https://lore.kernel.org/linux-nfs/20220907195259.926736-1-anna@kernel.org/T/#t
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:17:09 +02:00
Chuck Lever
2ec65dc663 NFSD: Fix possible sleep during nfsd4_release_lockowner()
commit ce3c4ad7f4ce5db7b4f08a1e237d8dd94b39180b upstream.

nfsd4_release_lockowner() holds clp->cl_lock when it calls
check_for_locks(). However, check_for_locks() calls nfsd_file_get()
/ nfsd_file_put() to access the backing inode's flc_posix list, and
nfsd_file_put() can sleep if the inode was recently removed.

Let's instead rely on the stateowner's reference count to gate
whether the release is permitted. This should be a reliable
indication of locks-in-use since file lock operations and
->lm_get_owner take appropriate references, which are released
appropriately when file locks are removed.

Reported-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-06 08:20:58 +02:00
Dan Carpenter
438068f491 NFSD: prevent underflow in nfssvc_decode_writeargs()
commit 184416d4b98509fb4c3d8fc3d6dc1437896cc159 upstream.

Smatch complains:

	fs/nfsd/nfsxdr.c:341 nfssvc_decode_writeargs()
	warn: no lower bound on 'args->len'

Change the type to unsigned to prevent this issue.

Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-20 09:08:09 +02:00
Chuck Lever
be711dea3b NFSD: Clamp WRITE offsets
commit 6260d9a56ab352b54891ec66ab0eced57d55abc6 upstream.

Ensure that a client cannot specify a WRITE range that falls in a
byte range outside what the kernel's internal types (such as loff_t,
which is signed) can represent. The kiocb iterators, invoked in
nfsd_vfs_write(), should properly limit write operations to within
the underlying file system's s_maxbytes.

Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-16 12:44:49 +01:00
Dai Ngo
78778ffb7c nfsd: nfsd4_setclientid_confirm mistakenly expires confirmed client.
commit ab451ea952fe9d7afefae55ddb28943a148247fe upstream.

From RFC 7530 Section 16.34.5:

o  The server has not recorded an unconfirmed { v, x, c, *, * } and
   has recorded a confirmed { v, x, c, *, s }.  If the principals of
   the record and of SETCLIENTID_CONFIRM do not match, the server
   returns NFS4ERR_CLID_INUSE without removing any relevant leased
   client state, and without changing recorded callback and
   callback_ident values for client { x }.

The current code intends to do what the spec describes above but
it forgot to set 'old' to NULL resulting to the confirmed client
to be expired.

Fixes: 2b63482185e6 ("nfsd: fix clid_inuse on mount with security change")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-08 18:16:29 +01:00
J. Bruce Fields
33645d3e22 nfsd: fix use-after-free due to delegation race
commit 548ec0805c399c65ed66c6641be467f717833ab5 upstream.

A delegation break could arrive as soon as we've called vfs_setlease.  A
delegation break runs a callback which immediately (in
nfsd4_cb_recall_prepare) adds the delegation to del_recall_lru.  If we
then exit nfs4_set_delegation without hashing the delegation, it will be
freed as soon as the callback is done with it, without ever being
removed from del_recall_lru.

Symptoms show up later as use-after-free or list corruption warnings,
usually in the laundromat thread.

I suspect aba2072f4523 "nfsd: grant read delegations to clients holding
writes" made this bug easier to hit, but I looked as far back as v3.0
and it looks to me it already had the same problem.  So I'm not sure
where the bug was introduced; it may have been there from the beginning.

Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[Salvatore Bonaccorso: Backport for context changes to versions which do
not have 20b7d86f29d3 ("nfsd: use boottime for lease expiry calculation")]
Signed-off-by: Salvatore Bonaccorso <carnil@debian.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-22 09:17:59 +01:00
Benjamin Coddington
652da40a92 NFSD: Keep existing listeners on portlist error
[ Upstream commit c20106944eb679fa3ab7e686fe5f6ba30fbc51e5 ]

If nfsd has existing listening sockets without any processes, then an error
returned from svc_create_xprt() for an additional transport will remove
those existing listeners.  We're seeing this in practice when userspace
attempts to create rpcrdma transports without having the rpcrdma modules
present before creating nfsd kernel processes.  Fix this by checking for
existing sockets before calling nfsd_destroy().

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-10-27 09:51:39 +02:00
Trond Myklebust
e32061d95f nfsd4: Handle the NFSv4 READDIR 'dircount' hint being zero
commit f2e717d655040d632c9015f19aa4275f8b16e7f2 upstream.

RFC3530 notes that the 'dircount' field may be zero, in which case the
recommendation is to ignore it, and only enforce the 'maxcount' field.
In RFC5661, this recommendation to ignore a zero valued field becomes a
requirement.

Fixes: aee377644146 ("nfsd4: fix rd_dircount enforcement")
Cc: <stable@vger.kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-17 10:08:32 +02:00
J. Bruce Fields
0f60f9d1e6 nfsd4: readdirplus shouldn't return parent of export
commit 51b2ee7d006a736a9126e8111d1f24e4fd0afaa6 upstream.

If you export a subdirectory of a filesystem, a READDIRPLUS on the root
of that export will return the filehandle of the parent with the ".."
entry.

The filehandle is optional, so let's just not return the filehandle for
".." if we're at the root of an export.

Note that once the client learns one filehandle outside of the export,
they can trivially access the rest of the export using further lookups.

However, it is also not very difficult to guess filehandles outside of
the export.  So exporting a subdirectory of a filesystem should
considered equivalent to providing access to the entire filesystem.  To
avoid confusion, we recommend only exporting entire filesystems.

Reported-by: Youjipeng <wangzhibei1999@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-23 15:48:45 +01:00
kazuo ito
0e9942d238 nfsd: Fix message level for normal termination
[ Upstream commit 4420440c57892779f265108f46f83832a88ca795 ]

The warning message from nfsd terminating normally
can confuse system adminstrators or monitoring software.

Though it's not exactly fair to pin-point a commit where it
originated, the current form in the current place started
to appear in:

Fixes: e096bbc6488d ("knfsd: remove special handling for SIGHUP")
Signed-off-by: kazuo ito <kzpn200@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29 13:47:00 +01:00
Chuck Lever
b9d61ebc60 NFSD: Add missing NFSv2 .pc_func methods
commit 6b3dccd48de8a4c650b01499a0b09d1e2279649e upstream.

There's no protection in nfsd_dispatch() against a NULL .pc_func
helpers. A malicious NFS client can trigger a crash by invoking the
unused/unsupported NFSv2 ROOT or WRITECACHE procedures.

The current NFSD dispatcher does not support returning a void reply
to a non-NULL procedure, so the reply to both of these is wrong, for
the moment.

Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05 11:07:02 +01:00
J. Bruce Fields
15fefb108c nfsd: apply umask on fs without ACL support
commit 22cf8419f1319ff87ec759d0ebdff4cbafaee832 upstream.

The server is failing to apply the umask when creating new objects on
filesystems without ACL support.

To reproduce this, you need to use NFSv4.2 and a client and server
recent enough to support umask, and you need to export a filesystem that
lacks ACL support (for example, ext4 with the "noacl" mount option).

Filesystems with ACL support are expected to take care of the umask
themselves (usually by calling posix_acl_create).

For filesystems without ACL support, this is up to the caller of
vfs_create(), vfs_mknod(), or vfs_mkdir().

Reported-by: Elliott Mitchell <ehem+debian@m5p.com>
Reported-by: Salvatore Bonaccorso <carnil@debian.org>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Fixes: 47057abde515 ("nfsd: add support for the umask attribute")
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-09 09:36:31 +02:00
Xiyu Yang
0c4fb76c4e nfsd: Fix svc_xprt refcnt leak when setup callback client failed
[ Upstream commit a4abc6b12eb1f7a533c2e7484cfa555454ff0977 ]

nfsd4_process_cb_update() invokes svc_xprt_get(), which increases the
refcount of the "c->cn_xprt".

The reference counting issue happens in one exception handling path of
nfsd4_process_cb_update(). When setup callback client failed, the
function forgets to decrease the refcnt increased by svc_xprt_get(),
causing a refcnt leak.

Fix this issue by calling svc_xprt_put() when setup callback client
failed.

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-25 15:41:49 +02:00
Vasily Averin
ea0f3c4ef7 nfsd: memory corruption in nfsd4_lock()
commit e1e8399eee72e9d5246d4d1bcacd793debe34dd3 upstream.

New struct nfsd4_blocked_lock allocated in find_or_allocate_block()
does not initialized nbl_list and nbl_lru.
If conflock allocation fails rollback can call list_del_init()
access uninitialized fields and corrupt memory.

v2: just initialize nbl_list and nbl_lru right after nbl allocation.

Fixes: 76d348fadff5 ("nfsd: have nfsd4_lock use blocking locks for v4.1+ lock")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:24:41 +02:00
Arnd Bergmann
a0f808e559 nfsd: fix jiffies/time_t mixup in LRU list
commit 9594497f2c78993cb66b696122f7c65528ace985 upstream.

The nfsd4_blocked_lock->nbl_time timestamp is recorded in jiffies,
but then compared to a CLOCK_REALTIME timestamp later on, which makes
no sense.

For consistency with the other timestamps, change this to use a time_t.

This is a change in behavior, which may cause regressions, but the
current code is not sensible. On a system with CONFIG_HZ=1000,
the 'time_after((unsigned long)nbl->nbl_time, (unsigned long)cutoff))'
check is false for roughly the first 18 days of uptime and then true
for the next 49 days.

Fixes: 7919d0a27f1e ("nfsd: add a LRU list for blocked locks")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:32:17 -05:00
Arnd Bergmann
7558ea7f5e nfsd: fix delay timer on 32-bit architectures
commit 2561c92b12f4f4e386d453556685f75775c0938b upstream.

The nfsd4_cb_layout_done() function takes a 'time_t' value,
multiplied by NSEC_PER_SEC*2 to get a nanosecond value.

This works fine on 64-bit architectures, but on 32-bit, any
value over 1 second results in a signed integer overflow
with unexpected results.

Cast one input to a 64-bit type in order to produce the
same result that we have on 64-bit architectures, regarless
of the type of nfsd4_lease.

Fixes: 6b9b21073d3b ("nfsd: give up on CB_LAYOUTRECALLs after two lease periods")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:32:17 -05:00
Scott Mayhew
46a3c4fb68 nfsd4: fix up replay_matches_cache()
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>
2020-01-09 10:17:57 +01:00
zhengbin
b7b8d8e667 nfsd: Return EPERM, not EACCES, in some SETATTR cases
[ 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>
2019-12-17 20:38:36 +01:00
Scott Mayhew
9a889ad76b nfsd: fix a warning in __cld_pipe_upcall()
[ 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>
2019-12-17 20:38:18 +01:00
Paul Menzel
8e394a633b nfsd: Fix overflow causing non-working mounts on 1 TB machines
[ 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>
2019-07-31 07:28:48 +02:00
J. Bruce Fields
5226ab7b1d nfsd: fix performance-limiting session calculation
[ 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>
2019-07-31 07:28:48 +02:00
J. Bruce Fields
3d583a3884 nfsd: give out fewer session slots as limit approaches
[ 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>
2019-07-31 07:28:48 +02:00
J. Bruce Fields
290613595a nfsd: increase DRC cache limit
[ 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>
2019-07-31 07:28:48 +02:00
J. Bruce Fields
76f53b8464 nfsd: allow fh_want_write to be called twice
[ 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>
2019-06-15 11:54:54 +02:00
Trond Myklebust
f08c652983 nfsd: Don't release the callback slot unless it was actually held
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>
2019-05-02 09:40:29 +02:00
Yihao Wu
2fa903f97d nfsd: fix wrong check in write_v4_end_grace()
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>
2019-03-23 14:35:28 +01:00
NeilBrown
c0edc30060 nfsd: fix memory corruption caused by readdir
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>
2019-03-23 14:35:28 +01:00
J. Bruce Fields
ff371bc83b nfsd4: catch some false session retries
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>
2019-02-12 19:46:14 +01:00
J. Bruce Fields
e74cfcb89e nfsd4: fix cached replies to solo SEQUENCE compounds
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>
2019-02-12 19:46:14 +01:00
J. Bruce Fields
51d0d8e65d nfsd4: fix crash on writing v4_end_grace before nfsd startup
[ 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>
2019-02-12 19:46:00 +01:00
Scott Mayhew
6d1c38aa47 nfsd: COPY and CLONE operations require the saved filehandle to be set
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>
2018-11-21 09:24:14 +01:00
Amir Goldstein
8a6cee344c vfs: swap names of {do,vfs}_clone_file_range()
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>
2018-11-10 07:48:33 -08:00
J. Bruce Fields
a4f7bea878 nfsd: fix corrupted reply to badly ordered compound
[ 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>
2018-10-03 17:00:53 -07:00
Scott Mayhew
5a47fe3efd nfsd: fix potential use-after-free in nfsd4_decode_getdeviceinfo
[ 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>
2018-08-03 07:50:22 +02:00
Scott Mayhew
89864c2e75 nfsd: restrict rd_maxcount to svc_max_payload in nfsd_encode_readdir
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>
2018-07-03 11:25:02 +02:00
J. Bruce Fields
9a0a509839 nfsd: fix incorrect umasks
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>
2018-04-19 08:56:21 +02:00
Jeff Layton
797bfd05d4 nfsd: remove blocked locks on client teardown
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>
2018-03-28 18:24:37 +02:00
Benjamin Coddington
14d920fc45 nfsd4: permit layoutget of executable-only files
[ 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>
2018-03-24 11:01:27 +01:00
Vasily Averin
02cfbaa6cd lockd: fix "list_add double add" caused by legacy signal interface
[ 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>
2018-02-03 17:39:08 +01:00