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2018-03-28nfsd: remove blocked locks on client teardownJeff Layton
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>
2018-03-24nfsd4: permit layoutget of executable-only filesBenjamin Coddington
[ 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>
2018-03-24NFS: don't try to cross a mountpount when there isn't one there.NeilBrown
[ Upstream commit 99bbf6ecc694dfe0b026e15359c5aa2a60b97a93 ] consider the sequence of commands: mkdir -p /import/nfs /import/bind /import/etc mount --bind / /import/bind mount --make-private /import/bind mount --bind /import/etc /import/bind/etc exportfs -o rw,no_root_squash,crossmnt,async,no_subtree_check localhost:/ mount -o vers=4 localhost:/ /import/nfs ls -l /import/nfs/etc You would not expect this to report a stale file handle. Yet it does. The manipulations under /import/bind cause the dentry for /etc to get the DCACHE_MOUNTED flag set, even though nothing is mounted on /etc. This causes nfsd to call nfsd_cross_mnt() even though there is no mountpoint. So an upcall to mountd for "/etc" is performed. The 'crossmnt' flag on the export of / causes mountd to report that /etc is exported as it is a descendant of /. It assumes the kernel wouldn't ask about something that wasn't a mountpoint. The filehandle returned identifies the filesystem and the inode number of /etc. When this filehandle is presented to rpc.mountd, via "nfsd.fh", the inode cannot be found associated with any name in /etc/exports, or with any mountpoint listed by getmntent(). So rpc.mountd says the filehandle doesn't exist. Hence ESTALE. This is fixed by teaching nfsd not to trust DCACHE_MOUNTED too much. It is just a hint, not a guarantee. Change nfsd_mountpoint() to return '1' for a certain mountpoint, '2' for a possible mountpoint, and 0 otherwise. Then change nfsd_crossmnt() to check if follow_down() actually found a mountpount and, if not, to avoid performing a lookup if the location is not known to certainly require an export-point. Signed-off-by: NeilBrown <neilb@suse.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>
2018-02-03lockd: fix "list_add double add" caused by legacy signal interfaceVasily Averin
[ 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@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03nfsd: check for use of the closed special stateidAndrew Elble
[ 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@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03nfsd: Ensure we check stateid validity in the seqid operation checksTrond Myklebust
[ 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@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03nfsd: CLOSE SHOULD return the invalid special stateid for NFSv4.x (x>0)Trond Myklebust
[ Upstream commit fb500a7cfee7f2f447d2bbf30cb59629feab6ac1 ] 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@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31nfsd: auth: Fix gid sorting when rootsquash enabledBen Hutchings
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>
2018-01-10kernel: make groups_sort calling a responsibility group_info allocatorsThiago Rafael Becker
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>
2017-12-20NFSD: fix nfsd_reset_versions for NFSv4.NeilBrown
[ Upstream commit 800a938f0bf9130c8256116649c0cc5806bfb2fd ] If you write "-2 -3 -4" to the "versions" file, it will notice that no versions are enabled, and nfsd_reset_versions() is called. This enables all major versions, not no minor versions. So we lose the invariant that NFSv4 is only advertised when at least one minor is enabled. Fix the code to explicitly enable minor versions for v4, change it to use nfsd_vers() to test and set, and simplify the code. Signed-off-by: NeilBrown <neilb@suse.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>
2017-12-20NFSD: fix nfsd_minorversion(.., NFSD_AVAIL)NeilBrown
[ Upstream commit 928c6fb3a9bfd6c5b287aa3465226add551c13c0 ] Current code will return 1 if the version is supported, and -1 if it isn't. This is confusing and inconsistent with the one place where this is used. So change to return 1 if it is supported, and zero if not. i.e. an error is never returned. Signed-off-by: NeilBrown <neilb@suse.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>
2017-12-05nfsd: fix panic in posix_unblock_lock called from nfs4_laundromatNaofumi Honda
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>
2017-12-05nfsd: Fix another OPEN stateid raceTrond Myklebust
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>
2017-12-05nfsd: Fix stateid races between OPEN and CLOSETrond Myklebust
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>
2017-11-30nfsd: deal with revoked delegations appropriatelyAndrew Elble
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>
2017-10-21nfsd/callback: Cleanup callback cred on shutdownKinglong Mee
[ Upstream commit f7d1ddbe7648af7460d23688c8c131342eb43b3a ] The rpccred gotten from rpc_lookup_machine_cred() should be put when state is shutdown. Signed-off-by: Kinglong Mee <kinglongmee@gmail.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>
2017-08-30nfsd: Limit end of page list when decoding NFSv4 WRITEChuck Lever
commit fc788f64f1f3eb31e87d4f53bcf1ab76590d5838 upstream. 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> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14fs: add i_blocksize()Fabian Frederick
commit 93407472a21b82f39c955ea7787e5bc7da100642 upstream. Replace all 1 << inode->i_blkbits and (1 << inode->i_blkbits) in fs branch. This patch also fixes multiple checkpatch warnings: WARNING: Prefer 'unsigned int' to bare use of 'unsigned' Thanks to Andrew Morton for suggesting more appropriate function instead of macro. [geliangtang@gmail.com: truncate: use i_blocksize()] Link: http://lkml.kernel.org/r/9c8b2cd83c8f5653805d43debde9fa8817e02fc4.1484895804.git.geliangtang@gmail.com Link: http://lkml.kernel.org/r/1481319905-10126-1-git-send-email-fabf@skynet.be Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Geliang Tang <geliangtang@gmail.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Ross Zwisler <ross.zwisler@linux.intel.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>
2017-06-14nfsd: Fix up the "supattr_exclcreat" attributesTrond Myklebust
commit b26b78cb726007533d81fdf90a62e915002ef5c8 upstream. If an NFSv4 client asks us for the supattr_exclcreat, then we must not return attributes that are unsupported by this minor version. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Fixes: 75976de6556f ("NFSD: Return word2 bitmask if setting security..,") Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14nfsd4: fix null dereference on replayJ. Bruce Fields
commit 9a307403d374b993061f5992a6e260c944920d0b upstream. if we receive a compound such that: - the sessionid, slot, and sequence number in the SEQUENCE op match a cached succesful reply with N ops, and - the Nth operation of the compound is a PUTFH, PUTPUBFH, PUTROOTFH, or RESTOREFH, then nfsd4_sequence will return 0 and set cstate->status to nfserr_replay_cache. The current filehandle will not be set. This will cause us to call check_nfsd_access with first argument NULL. To nfsd4_compound it looks like we just succesfully executed an operation that set a filehandle, but the current filehandle is not set. Fix this by moving the nfserr_replay_cache earlier. There was never any reason to have it after the encode_op label, since the only case where he hit that is when opdesc->op_func sets it. Note that there are two ways we could hit this case: - a client is resending a previously sent compound that ended with one of the four PUTFH-like operations, or - a client is sending a *new* compound that (incorrectly) shares sessionid, slot, and sequence number with a previously sent compound, and the length of the previously sent compound happens to match the position of a PUTFH-like operation in the new compound. The second is obviously incorrect client behavior. The first is also very strange--the only purpose of a PUTFH-like operation is to set the current filehandle to be used by the following operation, so there's no point in having it as the last in a compound. So it's likely this requires a buggy or malicious client to reproduce. Reported-by: Scott Mayhew <smayhew@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25nfsd: encoders mustn't use unitialized values in error casesJ. Bruce Fields
commit f961e3f2acae94b727380c0b74e2d3954d0edf79 upstream. In error cases, lgp->lg_layout_type may be out of bounds; so we shouldn't be using it until after the check of nfserr. This was seen to crash nfsd threads when the server receives a LAYOUTGET request with a large layout type. GETDEVICEINFO has the same problem. Reported-by: Ari Kauppi <Ari.Kauppi@synopsys.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25nfsd: fix undefined behavior in nfsd4_layout_verifyAri Kauppi
commit b550a32e60a4941994b437a8d662432a486235a5 upstream. UBSAN: Undefined behaviour in fs/nfsd/nfs4proc.c:1262:34 shift exponent 128 is too large for 32-bit type 'int' Depending on compiler+architecture, this may cause the check for layout_type to succeed for overly large values (which seems to be the case with amd64). The large value will be later used in de-referencing nfsd4_layout_ops for function pointers. Reported-by: Jani Tuovila <tuovila@synopsys.com> Signed-off-by: Ari Kauppi <ari@synopsys.com> [colin.king@canonical.com: use LAYOUT_TYPE_MAX instead of 32] Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-03nfsd: stricter decoding of write-like NFSv2/v3 opsJ. Bruce Fields
commit 13bf9fbff0e5e099e2b6f003a0ab8ae145436309 upstream. The NFSv2/v3 code does not systematically check whether we decode past the end of the buffer. This generally appears to be harmless, but there are a few places where we do arithmetic on the pointers involved and don't account for the possibility that a length could be negative. Add checks to catch these. Reported-by: Tuomas Haanpää <thaan@synopsys.com> Reported-by: Ari Kauppi <ari@synopsys.com> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-03nfsd4: minor NFSv2/v3 write decoding cleanupJ. Bruce Fields
commit db44bac41bbfc0c0d9dd943092d8bded3c9db19b upstream. Use a couple shortcuts that will simplify a following bugfix. Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-03nfsd: check for oversized NFSv2/v3 argumentsJ. Bruce Fields
commit e6838a29ecb484c97e4efef9429643b9851fba6e upstream. A client can append random data to the end of an NFSv2 or NFSv3 RPC call without our complaining; we'll just stop parsing at the end of the expected data and ignore the rest. Encoded arguments and replies are stored together in an array of pages, and if a call is too large it could leave inadequate space for the reply. This is normally OK because NFS RPC's typically have either short arguments and long replies (like READ) or long arguments and short replies (like WRITE). But a client that sends an incorrectly long reply can violate those assumptions. This was observed to cause crashes. Also, several operations increment rq_next_page in the decode routine before checking the argument size, which can leave rq_next_page pointing well past the end of the page array, causing trouble later in svc_free_pages. So, following a suggestion from Neil Brown, add a central check to enforce our expectation that no NFSv2/v3 call has both a large call and a large reply. As followup we may also want to rewrite the encoding routines to check more carefully that they aren't running off the end of the page array. We may also consider rejecting calls that have any extra garbage appended. That would be safer, and within our rights by spec, but given the age of our server and the NFS protocol, and the fact that we've never enforced this before, we may need to balance that against the possibility of breaking some oddball client. Reported-by: Tuomas Haanpää <thaan@synopsys.com> Reported-by: Ari Kauppi <ari@synopsys.com> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08nfsd: map the ENOKEY to nfserr_perm for avoiding warningKinglong Mee
commit c952cd4e949ab3d07287efc2e80246e03727d15d upstream. Now that Ext4 and f2fs filesystems support encrypted directories and files, attempts to access those files may return ENOKEY, resulting in the following WARNING. Map ENOKEY to nfserr_perm instead of nfserr_io. [ 1295.411759] ------------[ cut here ]------------ [ 1295.411787] WARNING: CPU: 0 PID: 12786 at fs/nfsd/nfsproc.c:796 nfserrno+0x74/0x80 [nfsd] [ 1295.411806] nfsd: non-standard errno: -126 [ 1295.411816] Modules linked in: nfsd nfs_acl auth_rpcgss nfsv4 nfs lockd fscache tun bridge stp llc fuse ip_set nfnetlink vmw_vsock_vmci_transport vsock snd_seq_midi snd_seq_midi_event coretemp crct10dif_pclmul crc32_generic crc32_pclmul snd_ens1371 gameport ghash_clmulni_intel snd_ac97_codec f2fs intel_rapl_perf ac97_bus snd_seq ppdev snd_pcm snd_rawmidi snd_timer vmw_balloon snd_seq_device snd joydev soundcore parport_pc parport nfit acpi_cpufreq tpm_tis vmw_vmci tpm_tis_core tpm shpchp i2c_piix4 grace sunrpc xfs libcrc32c vmwgfx drm_kms_helper ttm drm crc32c_intel e1000 mptspi scsi_transport_spi serio_raw mptscsih mptbase ata_generic pata_acpi fjes [last unloaded: nfs_acl] [ 1295.412522] CPU: 0 PID: 12786 Comm: nfsd Tainted: G W 4.11.0-rc1+ #521 [ 1295.412959] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015 [ 1295.413814] Call Trace: [ 1295.414252] dump_stack+0x63/0x86 [ 1295.414666] __warn+0xcb/0xf0 [ 1295.415087] warn_slowpath_fmt+0x5f/0x80 [ 1295.415502] ? put_filp+0x42/0x50 [ 1295.415927] nfserrno+0x74/0x80 [nfsd] [ 1295.416339] nfsd_open+0xd7/0x180 [nfsd] [ 1295.416746] nfs4_get_vfs_file+0x367/0x3c0 [nfsd] [ 1295.417182] ? security_inode_permission+0x41/0x60 [ 1295.417591] nfsd4_process_open2+0x9b2/0x1200 [nfsd] [ 1295.418007] nfsd4_open+0x481/0x790 [nfsd] [ 1295.418409] nfsd4_proc_compound+0x395/0x680 [nfsd] [ 1295.418812] nfsd_dispatch+0xb8/0x1f0 [nfsd] [ 1295.419233] svc_process_common+0x4d9/0x830 [sunrpc] [ 1295.419631] svc_process+0xfe/0x1b0 [sunrpc] [ 1295.420033] nfsd+0xe9/0x150 [nfsd] [ 1295.420420] kthread+0x101/0x140 [ 1295.420802] ? nfsd_destroy+0x60/0x60 [nfsd] [ 1295.421199] ? kthread_park+0x90/0x90 [ 1295.421598] ret_from_fork+0x2c/0x40 [ 1295.421996] ---[ end trace 0d5a969cd7852e1f ]--- Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-12nfsd: special case truncates some moreChristoph Hellwig
commit 783112f7401ff449d979530209b3f6c2594fdb4e upstream. Both the NFS protocols and the Linux VFS use a setattr operation with a bitmap of attributes to set to set various file attributes including the file size and the uid/gid. The Linux syscalls never mix size updates with unrelated updates like the uid/gid, and some file systems like XFS and GFS2 rely on the fact that truncates don't update random other attributes, and many other file systems handle the case but do not update the other attributes in the same transaction. NFSD on the other hand passes the attributes it gets on the wire more or less directly through to the VFS, leading to updates the file systems don't expect. XFS at least has an assert on the allowed attributes, which caught an unusual NFS client setting the size and group at the same time. To handle this issue properly this splits the notify_change call in nfsd_setattr into two separate ones. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-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>
2017-03-12nfsd: minor nfsd_setattr cleanupChristoph Hellwig
commit 758e99fefe1d9230111296956335cd35995c0eaf upstream. Simplify exit paths, size_change use. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-09NFSD: Fix a null reference case in find_or_create_lock_stateid()Kinglong Mee
commit d19fb70dd68c4e960e2ac09b0b9c79dfdeefa726 upstream. nfsd assigns the nfs4_free_lock_stateid to .sc_free in init_lock_stateid(). If nfsd doesn't go through init_lock_stateid() and put stateid at end, there is a NULL reference to .sc_free when calling nfs4_put_stid(ns). This patch let the nfs4_stid.sc_free assignment to nfs4_alloc_stid(). Fixes: 356a95ece7aa "nfsd: clean up races in lock stateid searching..." Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-01nfsd: Fix general protection fault in release_lock_stateid()Chuck Lever
When I push NFSv4.1 / RDMA hard, (xfstests generic/089, for example), I get this crash on the server: Oct 28 22:04:30 klimt kernel: general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC Oct 28 22:04:30 klimt kernel: Modules linked in: cts rpcsec_gss_krb5 iTCO_wdt iTCO_vendor_support sb_edac edac_core x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm btrfs irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper cryptd xor pcspkr raid6_pq i2c_i801 i2c_smbus lpc_ich mfd_core sg mei_me mei ioatdma shpchp wmi ipmi_si ipmi_msghandler rpcrdma ib_ipoib rdma_ucm acpi_power_meter acpi_pad ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c mlx4_ib mlx4_en ib_core sr_mod cdrom sd_mod ast drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel igb ahci libahci ptp mlx4_core pps_core dca libata i2c_algo_bit i2c_core dm_mirror dm_region_hash dm_log dm_mod Oct 28 22:04:30 klimt kernel: CPU: 7 PID: 1558 Comm: nfsd Not tainted 4.9.0-rc2-00005-g82cd754 #8 Oct 28 22:04:30 klimt kernel: Hardware name: Supermicro Super Server/X10SRL-F, BIOS 1.0c 09/09/2015 Oct 28 22:04:30 klimt kernel: task: ffff880835c3a100 task.stack: ffff8808420d8000 Oct 28 22:04:30 klimt kernel: RIP: 0010:[<ffffffffa05a759f>] [<ffffffffa05a759f>] release_lock_stateid+0x1f/0x60 [nfsd] Oct 28 22:04:30 klimt kernel: RSP: 0018:ffff8808420dbce0 EFLAGS: 00010246 Oct 28 22:04:30 klimt kernel: RAX: ffff88084e6660f0 RBX: ffff88084e667020 RCX: 0000000000000000 Oct 28 22:04:30 klimt kernel: RDX: 0000000000000007 RSI: 0000000000000000 RDI: ffff88084e667020 Oct 28 22:04:30 klimt kernel: RBP: ffff8808420dbcf8 R08: 0000000000000001 R09: 0000000000000000 Oct 28 22:04:30 klimt kernel: R10: ffff880835c3a100 R11: ffff880835c3aca8 R12: 6b6b6b6b6b6b6b6b Oct 28 22:04:30 klimt kernel: R13: ffff88084e6670d8 R14: ffff880835f546f0 R15: ffff880835f1c548 Oct 28 22:04:30 klimt kernel: FS: 0000000000000000(0000) GS:ffff88087bdc0000(0000) knlGS:0000000000000000 Oct 28 22:04:30 klimt kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Oct 28 22:04:30 klimt kernel: CR2: 00007ff020389000 CR3: 0000000001c06000 CR4: 00000000001406e0 Oct 28 22:04:30 klimt kernel: Stack: Oct 28 22:04:30 klimt kernel: ffff88084e667020 0000000000000000 ffff88084e6670d8 ffff8808420dbd20 Oct 28 22:04:30 klimt kernel: ffffffffa05ac80d ffff880835f54548 ffff88084e640008 ffff880835f545b0 Oct 28 22:04:30 klimt kernel: ffff8808420dbd70 ffffffffa059803d ffff880835f1c768 0000000000000870 Oct 28 22:04:30 klimt kernel: Call Trace: Oct 28 22:04:30 klimt kernel: [<ffffffffa05ac80d>] nfsd4_free_stateid+0xfd/0x1b0 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa059803d>] nfsd4_proc_compound+0x40d/0x690 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa0583114>] nfsd_dispatch+0xd4/0x1d0 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa047bbf9>] svc_process_common+0x3d9/0x700 [sunrpc] Oct 28 22:04:30 klimt kernel: [<ffffffffa047ca64>] svc_process+0xf4/0x330 [sunrpc] Oct 28 22:04:30 klimt kernel: [<ffffffffa05827ca>] nfsd+0xfa/0x160 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa05826d0>] ? nfsd_destroy+0x170/0x170 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffff810b367b>] kthread+0x10b/0x120 Oct 28 22:04:30 klimt kernel: [<ffffffff810b3570>] ? kthread_stop+0x280/0x280 Oct 28 22:04:30 klimt kernel: [<ffffffff8174e8ba>] ret_from_fork+0x2a/0x40 Oct 28 22:04:30 klimt kernel: Code: c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 55 41 54 53 48 8b 87 b0 00 00 00 48 89 fb 4c 8b a0 98 00 00 00 <49> 8b 44 24 20 48 8d b8 80 03 00 00 e8 10 66 1a e1 48 89 df e8 Oct 28 22:04:30 klimt kernel: RIP [<ffffffffa05a759f>] release_lock_stateid+0x1f/0x60 [nfsd] Oct 28 22:04:30 klimt kernel: RSP <ffff8808420dbce0> Oct 28 22:04:30 klimt kernel: ---[ end trace cf5d0b371973e167 ]--- Jeff Layton says: > Hm...now that I look though, this is a little suspicious: > > struct nfs4_openowner *oo = openowner(stp->st_openstp->st_stateowner); > > I wonder if it's possible for the openstateid to have already been > destroyed at this point. > > We might be better off doing something like this to get the client pointer: > > stp->st_stid.sc_client; > > ...which should be more direct and less dependent on other stateids > staying valid. With the suggested change, I am no longer able to reproduce the above oops. v2: Fix unhash_lock_stateid() as well Fix-suggested-by: Jeff Layton <jlayton@redhat.com> Fixes: 42691398be08 ('nfsd: Fix race between FREE_STATEID and LOCK') Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-24nfsd: move blocked lock handling under a dedicated spinlockJeff Layton
Bruce was hitting some lockdep warnings in testing, showing that we could hit a deadlock with the new CB_NOTIFY_LOCK handling, involving a rather complex situation involving four different spinlocks. The crux of the matter is that we end up taking the nn->client_lock in the lm_notify handler. The simplest fix is to just declare a new per-nfsd_net spinlock to protect the new CB_NOTIFY_LOCK structures. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-13Merge tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd updates from Bruce Fields: "Some RDMA work and some good bugfixes, and two new features that could benefit from user testing: - Anna Schumacker contributed a simple NFSv4.2 COPY implementation. COPY is already supported on the client side, so a call to copy_file_range() on a recent client should now result in a server-side copy that doesn't require all the data to make a round trip to the client and back. - Jeff Layton implemented callbacks to notify clients when contended locks become available, which should reduce latency on workloads with contended locks" * tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linux: NFSD: Implement the COPY call nfsd: handle EUCLEAN nfsd: only WARN once on unmapped errors exportfs: be careful to only return expected errors. nfsd4: setclientid_confirm with unmatched verifier should fail nfsd: randomize SETCLIENTID reply to help distinguish servers nfsd: set the MAY_NOTIFY_LOCK flag in OPEN replies nfs: add a new NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK constant nfsd: add a LRU list for blocked locks nfsd: have nfsd4_lock use blocking locks for v4.1+ locks nfsd: plumb in a CB_NOTIFY_LOCK operation NFSD: fix corruption in notifier registration svcrdma: support Remote Invalidation svcrdma: Server-side support for rpcrdma_connect_private rpcrdma: RDMA/CM private message data structure svcrdma: Skip put_page() when send_reply() fails svcrdma: Tail iovec leaves an orphaned DMA mapping nfsd: fix dprintk in nfsd4_encode_getdeviceinfo nfsd: eliminate cb_minorversion field nfsd: don't set a FL_LAYOUT lease for flexfiles layouts
2016-10-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more vfs updates from Al Viro: ">rename2() work from Miklos + current_time() from Deepa" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: Replace current_fs_time() with current_time() fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps fs: Replace CURRENT_TIME with current_time() for inode timestamps fs: proc: Delete inode time initializations in proc_alloc_inode() vfs: Add current_time() api vfs: add note about i_op->rename changes to porting fs: rename "rename2" i_op to "rename" vfs: remove unused i_op->rename fs: make remaining filesystems use .rename2 libfs: support RENAME_NOREPLACE in simple_rename() fs: support RENAME_NOREPLACE for local filesystems ncpfs: fix unused variable warning
2016-10-10Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted misc bits and pieces. There are several single-topic branches left after this (rename2 series from Miklos, current_time series from Deepa Dinamani, xattr series from Andreas, uaccess stuff from from me) and I'd prefer to send those separately" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (39 commits) proc: switch auxv to use of __mem_open() hpfs: support FIEMAP cifs: get rid of unused arguments of CIFSSMBWrite() posix_acl: uapi header split posix_acl: xattr representation cleanups fs/aio.c: eliminate redundant loads in put_aio_ring_file fs/internal.h: add const to ns_dentry_operations declaration compat: remove compat_printk() fs/buffer.c: make __getblk_slow() static proc: unsigned file descriptors fs/file: more unsigned file descriptors fs: compat: remove redundant check of nr_segs cachefiles: Fix attempt to read i_blocks after deleting file [ver #2] cifs: don't use memcpy() to copy struct iov_iter get rid of separate multipage fault-in primitives fs: Avoid premature clearing of capabilities fs: Give dentry to inode_change_ok() instead of inode fuse: Propagate dentry down to inode_change_ok() ceph: Propagate dentry down to inode_change_ok() xfs: Propagate dentry down to inode_change_ok() ...
2016-10-08Merge remote-tracking branch 'jk/vfs' into work.miscAl Viro
2016-10-07cred: simpler, 1D supplementary groupsAlexey Dobriyan
Current supplementary groups code can massively overallocate memory and is implemented in a way so that access to individual gid is done via 2D array. If number of gids is <= 32, memory allocation is more or less tolerable (140/148 bytes). But if it is not, code allocates full page (!) regardless and, what's even more fun, doesn't reuse small 32-entry array. 2D array means dependent shifts, loads and LEAs without possibility to optimize them (gid is never known at compile time). All of the above is unnecessary. Switch to the usual trailing-zero-len-array scheme. Memory is allocated with kmalloc/vmalloc() and only as much as needed. Accesses become simpler (LEA 8(gi,idx,4) or even without displacement). Maximum number of gids is 65536 which translates to 256KB+8 bytes. I think kernel can handle such allocation. On my usual desktop system with whole 9 (nine) aux groups, struct group_info shrinks from 148 bytes to 44 bytes, yay! Nice side effects: - "gi->gid[i]" is shorter than "GROUP_AT(gi, i)", less typing, - fix little mess in net/ipv4/ping.c should have been using GROUP_AT macro but this point becomes moot, - aux group allocation is persistent and should be accounted as such. Link: http://lkml.kernel.org/r/20160817201927.GA2096@p183.telecom.by Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Vasily Kulikov <segoon@openwall.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07NFSD: Implement the COPY callAnna Schumaker
I only implemented the sync version of this call, since it's the easiest. I can simply call vfs_copy_range() and have the vfs do the right thing for the filesystem being exported. Signed-off-by: Anna Schumaker <bjschuma@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-07nfsd: handle EUCLEANJ. Bruce Fields
Eric Sandeen reports that xfs can return this if filesystem corruption prevented completing the operation. Reported-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-07nfsd: only WARN once on unmapped errorsJ. Bruce Fields
No need to spam the logs here. The only drawback is losing information if we ever encounter two different unmapped errors, but in practice we've rarely see even one. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-27fs: Replace current_fs_time() with current_time()Deepa Dinamani
current_fs_time() uses struct super_block* as an argument. As per Linus's suggestion, this is changed to take struct inode* as a parameter instead. This is because the function is primarily meant for vfs inode timestamps. Also the function was renamed as per Arnd's suggestion. Change all calls to current_fs_time() to use the new current_time() function instead. current_fs_time() will be deleted. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-26nfsd4: setclientid_confirm with unmatched verifier should failJ. Bruce Fields
A setclientid_confirm with (clientid, verifier) both matching an existing confirmed record is assumed to be a replay, but if the verifier doesn't match, it shouldn't be. This would be a very rare case, except that clients following https://tools.ietf.org/html/rfc7931#section-5.8 may depend on the failure. Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: randomize SETCLIENTID reply to help distinguish serversJ. Bruce Fields
NFSv4.1 has built-in trunking support that allows a client to determine whether two connections to two different IP addresses are actually to the same server. NFSv4.0 does not, but RFC 7931 attempts to provide clients a means to do this, basically by performing a SETCLIENTID to one address and confirming it with a SETCLIENTID_CONFIRM to the other. Linux clients since 05f4c350ee02 "NFS: Discover NFSv4 server trunking when mounting" implement a variation on this suggestion. It is possible that other clients do too. This depends on the clientid and verifier not being accepted by an unrelated server. Since both are 64-bit values, that would be very unlikely if they were random numbers. But they aren't: knfsd generates the 64-bit clientid by concatenating the 32-bit boot time (in seconds) and a counter. This makes collisions between clientids generated by the same server extremely unlikely. But collisions are very likely between clientids generated by servers that boot at the same time, and it's quite common for multiple servers to boot at the same time. The verifier is a concatenation of the SETCLIENTID time (in seconds) and a counter, so again collisions between different servers are likely if multiple SETCLIENTIDs are done at the same time, which is a common case. Therefore recent NFSv4.0 clients may decide two different servers are really the same, and mount a filesystem from the wrong server. Fortunately the Linux client, since 55b9df93ddd6 "nfsv4/v4.1: Verify the client owner id during trunking detection", only does this when given the non-default "migration" mount option. The fault is really with RFC 7931, and needs a client fix, but in the meantime we can mitigate the chance of these collisions by randomizing the starting value of the counters used to generate clientids and verifiers. Reported-by: Frank Sorenson <fsorenso@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: set the MAY_NOTIFY_LOCK flag in OPEN repliesJeff Layton
If we are using v4.1+, then we can send notification when contended locks become free. Inform the client of that fact. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: add a LRU list for blocked locksJeff Layton
It's possible for a client to call in on a lock that is blocked for a long time, but discontinue polling for it. A malicious client could even set a lock on a file, and then spam the server with failing lock requests from different lockowners that pile up in a DoS attack. Add the blocked lock structures to a per-net namespace LRU when hashing them, and timestamp them. If the lock request is not revisited after a lease period, we'll drop it under the assumption that the client is no longer interested. This also gives us a mechanism to clean up these objects at server shutdown time as well. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: have nfsd4_lock use blocking locks for v4.1+ locksJeff Layton
Create a new per-lockowner+per-inode structure that contains a file_lock. Have nfsd4_lock add this structure to the lockowner's list prior to setting the lock. Then call the vfs and request a blocking lock (by setting FL_SLEEP). If we get anything besides FILE_LOCK_DEFERRED back, then we dequeue the block structure and free it. When the next lock request comes in, we'll look for an existing block for the same filehandle and dequeue and reuse it if there is one. When the lock comes free (a'la an lm_notify call), we dequeue it from the lockowner's list and kick off a CB_NOTIFY_LOCK callback to inform the client that it should retry the lock request. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: plumb in a CB_NOTIFY_LOCK operationJeff Layton
Add the encoding/decoding for CB_NOTIFY_LOCK operations. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26NFSD: fix corruption in notifier registrationVasily Averin
By design notifier can be registered once only, however nfsd registers the same inetaddr notifiers per net-namespace. When this happen it corrupts list of notifiers, as result some notifiers can be not called on proper event, traverse on list can be cycled forever, and second unregister can access already freed memory. Cc: stable@vger.kernel.org fixes: 36684996 ("nfsd: Register callbacks on the inetaddr_chain and inet6addr_chain") Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-23nfsd: fix dprintk in nfsd4_encode_getdeviceinfoJeff Layton
nfserr is big-endian, so we should convert it to host-endian before printing it. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-22fs: Give dentry to inode_change_ok() instead of inodeJan Kara
inode_change_ok() will be resposible for clearing capabilities and IMA extended attributes and as such will need dentry. Give it as an argument to inode_change_ok() instead of an inode. Also rename inode_change_ok() to setattr_prepare() to better relect that it does also some modifications in addition to checks. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz>
2016-09-16nfsd: eliminate cb_minorversion fieldJeff Layton
We already have that info in the client pointer. No need to pass around a copy. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>