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path: root/fs/nfsd/nfs4state.c
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2023-11-28nfsd: fix file memleak on client_opens_releaseMahmoud Adam
commit bc1b5acb40201a0746d68a7d7cfc141899937f4f upstream. seq_release should be called to free the allocated seq_file Cc: stable@vger.kernel.org # v5.3+ Signed-off-by: Mahmoud Adam <mngyadam@amazon.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Fixes: 78599c42ae3c ("nfsd4: add file to display list of client's opens") Reviewed-by: NeilBrown <neilb@suse.de> Tested-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-30nfsd: Fix race to FREE_STATEID and cl_revokedBenjamin Coddington
commit 3b816601e279756e781e6c4d9b3f3bd21a72ac67 upstream. We have some reports of linux NFS clients that cannot satisfy a linux knfsd server that always sets SEQ4_STATUS_RECALLABLE_STATE_REVOKED even though those clients repeatedly walk all their known state using TEST_STATEID and receive NFS4_OK for all. Its possible for revoke_delegation() to set NFS4_REVOKED_DELEG_STID, then nfsd4_free_stateid() finds the delegation and returns NFS4_OK to FREE_STATEID. Afterward, revoke_delegation() moves the same delegation to cl_revoked. This would produce the observed client/server effect. Fix this by ensuring that the setting of sc_type to NFS4_REVOKED_DELEG_STID and move to cl_revoked happens within the same cl_lock. This will allow nfsd4_free_stateid() to properly remove the delegation from cl_revoked. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2217103 Link: https://bugzilla.redhat.com/show_bug.cgi?id=2176575 Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Cc: stable@vger.kernel.org # v4.17+ 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>
2023-08-03nfsd: Remove incorrect check in nfsd4_validate_stateidTrond Myklebust
commit f75546f58a70da5cfdcec5a45ffc377885ccbee8 upstream. 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some event occurred that requires it to check all the stateids for validity and call FREE_STATEID on the ones that have been revoked.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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10nfsd: don't hand out delegation on setuid files being opened for writeJeff Layton
[ Upstream commit 826b67e6376c2a788e3a62c4860dcd79500a27d5 ] We had a bug report that xfstest generic/355 was failing on NFSv4.0. This test sets various combinations of setuid/setgid modes and tests whether DIO writes will cause them to be stripped. What I found was that the server did properly strip those bits, but the client didn't notice because it held a delegation that was not recalled. The recall didn't occur because the client itself was the one generating the activity and we avoid recalls in that case. Clearing setuid bits is an "implicit" activity. The client didn't specifically request that we do that, so we need the server to issue a CB_RECALL, or avoid the situation entirely by not issuing a delegation. The easiest fix here is to simply not give out a delegation if the file is being opened for write, and the mode has the setuid and/or setgid bit set. Note that there is a potential race between the mode and lease being set, so we test for this condition both before and after setting the lease. This patch fixes generic/355, generic/683 and generic/684 for me. (Note that 355 fails only on v4.0, and 683 and 684 require NFSv4.2 to run and fail). Reported-by: Boyang Xue <bxue@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-10nfsd: fix courtesy client with deny mode handling in nfs4_upgrade_openJeff Layton
[ Upstream commit dcd779dc46540e174a6ac8d52fbed23593407317 ] The nested if statements here make no sense, as you can never reach "else" branch in the nested statement. Fix the error handling for when there is a courtesy client that holds a conflicting deny mode. Fixes: 3d6942715180 ("NFSD: add support for share reservation conflict to courteous server") Reported-by: 張智諺 <cc85nod@gmail.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-10NFSD: fix problems with cleanup on errors in nfsd4_copyDai Ngo
[ Upstream commit 81e722978ad21072470b73d8f6a50ad62c7d5b7d ] When nfsd4_copy fails to allocate memory for async_copy->cp_src, or nfs4_init_copy_state fails, it calls cleanup_async_copy to do the cleanup for the async_copy which causes page fault since async_copy is not yet initialized. This patche rearranges the order of initializing the fields in async_copy and adds checks in cleanup_async_copy to skip un-initialized fields. Fixes: ce0887ac96d3 ("NFSD add nfs4 inter ssc to nfsd4_copy") Fixes: 87689df69491 ("NFSD: Shrink size of struct nfsd4_copy") 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> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18nfsd: fix handling of cached open files in nfsd4_open codepathJeff Layton
[ Upstream commit 0b3a551fa58b4da941efeb209b3770868e2eddd7 ] Commit fb70bf124b05 ("NFSD: Instantiate a struct file when creating a regular NFSv4 file") added the ability to cache an open fd over a compound. There are a couple of problems with the way this currently works: It's racy, as a newly-created nfsd_file can end up with its PENDING bit cleared while the nf is hashed, and the nf_file pointer is still zeroed out. Other tasks can find it in this state and they expect to see a valid nf_file, and can oops if nf_file is NULL. Also, there is no guarantee that we'll end up creating a new nfsd_file if one is already in the hash. If an extant entry is in the hash with a valid nf_file, nfs4_get_vfs_file will clobber its nf_file pointer with the value of op_file and the old nf_file will leak. Fix both issues by making a new nfsd_file_acquirei_opened variant that takes an optional file pointer. If one is present when this is called, we'll take a new reference to it instead of trying to open the file. If the nfsd_file already has a valid nf_file, we'll just ignore the optional file and pass the nfsd_file back as-is. Also rework the tracepoints a bit to allow for an "opened" variant and don't try to avoid counting acquisitions in the case where we already have a cached open file. Fixes: fb70bf124b05 ("NFSD: Instantiate a struct file when creating a regular NFSv4 file") Cc: Trond Myklebust <trondmy@hammerspace.com> Reported-by: Stanislav Saner <ssaner@redhat.com> Reported-and-Tested-by: Ruben Vestergaard <rubenv@drcmr.dk> Reported-and-Tested-by: Torkil Svensgaard <torkil@drcmr.dk> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18NFSD: Revert "NFSD: NFSv4 CLOSE should release an nfsd_file immediately"Chuck Lever
[ Upstream commit dcf3f80965ca787c70def402cdf1553c93c75529 ] This reverts commit 5e138c4a750dc140d881dab4a8804b094bbc08d2. That commit attempted to make files available to other users as soon as all NFSv4 clients were done with them, rather than waiting until the filecache LRU had garbage collected them. It gets the reference counting wrong, for one thing. But it also misses that DELEGRETURN should release a file in the same fashion. In fact, any nfsd_file_put() on an file held open by an NFSv4 client needs potentially to release the file immediately... Clear the way for implementing that idea. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: NeilBrown <neilb@suse.de> Stable-dep-of: 0b3a551fa58b ("nfsd: fix handling of cached open files in nfsd4_open codepath") Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31nfsd: don't call nfsd_file_put from client states seqfile displayJeff Layton
[ Upstream commit e0aa651068bfd520afcd357af8ecd2de005fc83d ] We had a report of this: BUG: sleeping function called from invalid context at fs/nfsd/filecache.c:440 ...with a stack trace showing nfsd_file_put being called from nfs4_show_open. This code has always tried to call fput while holding a spinlock, but we recently changed this to use the filecache, and that started triggering the might_sleep() in nfsd_file_put. states_start takes and holds the cl_lock while iterating over the client's states, and we can't sleep with that held. Have the various nfs4_show_* functions instead hold the fi_lock instead of taking a nfsd_file reference. Fixes: 78599c42ae3c ("nfsd4: add file to display list of client's opens") Link: https://bugzilla.redhat.com/show_bug.cgi?id=2138357 Reported-by: Zhi Li <yieli@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-11Merge tag 'nfsd-6.1-4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux Pull nfsd fixes from Chuck Lever: - Fix an export leak - Fix a potential tracepoint crash * tag 'nfsd-6.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: nfsd: put the export reference in nfsd4_verify_deleg_dentry nfsd: fix use-after-free in nfsd_file_do_acquire tracepoint
2022-11-08nfsd: put the export reference in nfsd4_verify_deleg_dentryJeff Layton
nfsd_lookup_dentry returns an export reference in addition to the dentry ref. Ensure that we put it too. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2138866 Fixes: 876c553cb410 ("NFSD: verify the opened dentry after setting a delegation") Reported-by: Yongcheng Yang <yoyang@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-10-11treewide: use get_random_u32() when possibleJason A. Donenfeld
The prandom_u32() function has been a deprecated inline wrapper around get_random_u32() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. The same also applies to get_random_int(), which is just a wrapper around get_random_u32(). This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Acked-by: Helge Deller <deller@gmx.de> # for parisc Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-09-26nfsd: extra checks when freeing delegation stateidsJeff Layton
We've had some reports of problems in the refcounting for delegation stateids that we've yet to track down. Add some extra checks to ensure that we've removed the object from various lists before freeing it. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2127067 Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26nfsd: make nfsd4_run_cb a bool return functionJeff Layton
queue_work can return false and not queue anything, if the work is already queued. If that happens in the case of a CB_RECALL, we'll have taken an extra reference to the stid that will never be put. Ensure we throw a warning in that case. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26nfsd: fix comments about spinlock handling with delegationsJeff Layton
Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26nfsd: only fill out return pointer on success in nfsd4_lookup_stateidJeff Layton
In the case of a revoked delegation, we still fill out the pointer even when returning an error, which is bad form. Only overwrite the pointer on success. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26NFSD: fix use-after-free on source server when doing inter-server copyDai Ngo
Use-after-free occurred when the laundromat tried to free expired cpntf_state entry on the s2s_cp_stateids list after inter-server copy completed. The sc_cp_list that the expired copy state was inserted on was already freed. When COPY completes, the Linux client normally sends LOCKU(lock_state x), FREE_STATEID(lock_state x) and CLOSE(open_state y) to the source server. The nfs4_put_stid call from nfsd4_free_stateid cleans up the copy state from the s2s_cp_stateids list before freeing the lock state's stid. However, sometimes the CLOSE was sent before the FREE_STATEID request. When this happens, the nfsd4_close_open_stateid call from nfsd4_close frees all lock states on its st_locks list without cleaning up the copy state on the sc_cp_list list. When the time the FREE_STATEID arrives the server returns BAD_STATEID since the lock state was freed. This causes the use-after-free error to occur when the laundromat tries to free the expired cpntf_state. This patch adds a call to nfs4_free_cpntf_statelist in nfsd4_close_open_stateid to clean up the copy state before calling free_ol_stateid_reaplist to free the lock state's stid on the reaplist. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26NFSD: Rename the fields in copy_stateid_tChuck Lever
Code maintenance: The name of the copy_stateid_t::sc_count field collides with the sc_count field in struct nfs4_stid, making the latter difficult to grep for when auditing stateid reference counting. No behavior change expected. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26nfsd: use DEFINE_SHOW_ATTRIBUTE to define client_info_fopsChenXiaoSong
Use DEFINE_SHOW_ATTRIBUTE helper macro to simplify the code. inode is converted from seq_file->file instead of seq_file->private in client_info_show(). Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26NFSD: add shrinker to reap courtesy clients on low memory conditionDai Ngo
Add courtesy_client_reaper to react to low memory condition triggered by the system memory shrinker. The delayed_work for the courtesy_client_reaper is scheduled on the shrinker's count callback using the laundry_wq. The shrinker's scan callback is not used for expiring the courtesy clients due to potential deadlocks. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26NFSD: keep track of the number of courtesy clients in the systemDai Ngo
Add counter nfs4_courtesy_client_count to nfsd_net to keep track of the number of courtesy clients in the system. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26NFSD: Add a mechanism to wait for a DELEGRETURNChuck Lever
Subsequent patches will use this mechanism to wake up an operation that is waiting for a client to return a delegation. The new tracepoint records whether the wait timed out or was properly awoken by the expected DELEGRETURN: nfsd-1155 [002] 83799.493199: nfsd_delegret_wakeup: xid=0x14b7d6ef fh_hash=0xf6826792 (timed out) Suggested-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-09-26NFSD: Add tracepoints to report NFSv4 callback completionsChuck Lever
Wireshark has always been lousy about dissecting NFSv4 callbacks, especially NFSv4.0 backchannel requests. Add tracepoints so we can surgically capture these events in the trace log. Tracepoints are time-stamped and ordered so that we can now observe the timing relationship between a CB_RECALL Reply and the client's DELEGRETURN Call. Example: nfsd-1153 [002] 211.986391: nfsd_cb_recall: addr=192.168.1.67:45767 client 62ea82e4:fee7492a stateid 00000003:00000001 nfsd-1153 [002] 212.095634: nfsd_compound: xid=0x0000002c opcnt=2 nfsd-1153 [002] 212.095647: nfsd_compound_status: op=1/2 OP_PUTFH status=0 nfsd-1153 [002] 212.095658: nfsd_file_put: hash=0xf72 inode=0xffff9291148c7410 ref=3 flags=HASHED|REFERENCED may=READ file=0xffff929103b3ea00 nfsd-1153 [002] 212.095661: nfsd_compound_status: op=2/2 OP_DELEGRETURN status=0 kworker/u25:8-148 [002] 212.096713: nfsd_cb_recall_done: client 62ea82e4:fee7492a stateid 00000003:00000001 status=0 Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-08-04NFSD: use (un)lock_inode instead of fh_(un)lock for file operationsNeilBrown
When locking a file to access ACLs and xattrs etc, use explicit locking with inode_lock() instead of fh_lock(). This means that the calls to fh_fill_pre/post_attr() are also explicit which improves readability and allows us to place them only where they are needed. Only the xattr calls need pre/post information. When locking a file we don't need I_MUTEX_PARENT as the file is not a parent of anything, so we can use inode_lock() directly rather than the inode_lock_nested() call that fh_lock() uses. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-08-04NFSD: reduce locking in nfsd_lookup()NeilBrown
nfsd_lookup() takes an exclusive lock on the parent inode, but no callers want the lock and it may not be needed at all if the result is in the dcache. Change nfsd_lookup_dentry() to not take the lock, and call lookup_one_len_locked() which takes lock only if needed. nfsd4_open() currently expects the lock to still be held, but that isn't necessary as nfsd_validate_delegated_dentry() provides required guarantees without the lock. NOTE: NFSv4 requires directory changeinfo for OPEN even when a create wasn't requested and no change happened. Now that nfsd_lookup() doesn't use fh_lock(), we need to explicitly fill the attributes when no create happens. A new fh_fill_both_attrs() is provided for that task. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-07-29NFSD: introduce struct nfsd_attrsNeilBrown
The attributes that nfsd might want to set on a file include 'struct iattr' as well as an ACL and security label. The latter two are passed around quite separately from the first, in part because they are only needed for NFSv4. This leads to some clumsiness in the code, such as the attributes NOT being set in nfsd_create_setattr(). We need to keep the directory locked until all attributes are set to ensure the file is never visibile without all its attributes. This need combined with the inconsistent handling of attributes leads to more clumsiness. As a first step towards tidying this up, introduce 'struct nfsd_attrs'. This is passed (by reference) to vfs.c functions that work with attributes, and is assembled by the various nfs*proc functions which call them. As yet only iattr is included, but future patches will expand this. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-07-29NFSD: verify the opened dentry after setting a delegationJeff Layton
Between opening a file and setting a delegation on it, someone could rename or unlink the dentry. If this happens, we do not want to grant a delegation on the open. On a CLAIM_NULL open, we're opening by filename, and we may (in the non-create case) or may not (in the create case) be holding i_rwsem when attempting to set a delegation. The latter case allows a race. After getting a lease, redo the lookup of the file being opened and validate that the resulting dentry matches the one in the open file description. To properly redo the lookup we need an rqst pointer to pass to nfsd_lookup_dentry(), so make sure that is available. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-07-29NFSD: drop fh argument from alloc_init_delegJeff Layton
Currently, we pass the fh of the opened file down through several functions so that alloc_init_deleg can pass it to delegation_blocked. The filehandle of the open file is available in the nfs4_file however, so there's no need to pass it in a separate argument. Drop the argument from alloc_init_deleg, nfs4_open_delegation and nfs4_set_delegation. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-07-29NFSD: limit the number of v4 clients to 1024 per 1GB of system memoryDai Ngo
Currently there is no limit on how many v4 clients are supported by the system. This can be a problem in systems with small memory configuration to function properly when a very large number of clients exist that creates memory shortage conditions. This patch enforces a limit of 1024 NFSv4 clients, including courtesy clients, per 1GB of system memory. When the number of the clients reaches the limit, requests that create new clients are returned with NFS4ERR_DELAY and the laundromat is kicked start to trim old clients. Due to the overhead of the upcall to remove the client record, the maximun number of clients the laundromat removes on each run is limited to 128. This is done to ensure the laundromat can still process the other tasks in a timely manner. Since there is now a limit of the number of clients, the 24-hr idle time limit of courtesy client is no longer needed and was removed. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-07-29NFSD: keep track of the number of v4 clients in the systemDai Ngo
Add counter nfs4_client_count to keep track of the total number of v4 clients, including courtesy clients, in the system. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-07-29NFSD: refactoring v4 specific code to a helper in nfs4state.cDai Ngo
This patch moves the v4 specific code from nfsd_init_net() to nfsd4_init_leases_net() helper in nfs4state.c Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-07-29NFSD: Ensure nf_inode is never dereferencedChuck Lever
The documenting comment for struct nf_file states: /* * A representation of a file that has been opened by knfsd. These are hashed * in the hashtable by inode pointer value. Note that this object doesn't * hold a reference to the inode by itself, so the nf_inode pointer should * never be dereferenced, only used for comparison. */ Replace the two existing dereferences to make the comment always true. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-07-29NFSD: NFSv4 CLOSE should release an nfsd_file immediatelyChuck Lever
The last close of a file should enable other accessors to open and use that file immediately. Leaving the file open in the filecache prevents other users from accessing that file until the filecache garbage-collects the file -- sometimes that takes several seconds. Reported-by: Wang Yugui <wangyugui@e16-tech.com> Link: https://bugzilla.linux-nfs.org/show_bug.cgi?387 Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-07-29NFSD: Separate tracepoints for acquire and createChuck Lever
These tracepoints collect different information: the create case does not open a file, so there's no nf_file available. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-26NFSD: Add documenting comment for nfsd4_release_lockowner()Chuck Lever
And return explicit nfserr values that match what is documented in the new comment / API contract. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-26NFSD: Modernize nfsd4_release_lockowner()Chuck Lever
Refactor: Use existing helpers that other lock operations use. This change removes several automatic variables, so re-organize the variable declarations for readability. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-26NFSD: Fix possible sleep during nfsd4_release_lockowner()Chuck Lever
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
2022-05-23NFSD: Move documenting comment for nfsd4_process_open2()Chuck Lever
Clean up nfsd4_open() by converting a large comment at the only call site for nfsd4_process_open2() to a kerneldoc comment in front of that function. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-23NFSD: Instantiate a struct file when creating a regular NFSv4 fileChuck Lever
There have been reports of races that cause NFSv4 OPEN(CREATE) to return an error even though the requested file was created. NFSv4 does not provide a status code for this case. To mitigate some of these problems, reorganize the NFSv4 OPEN(CREATE) logic to allocate resources before the file is actually created, and open the new file while the parent directory is still locked. Two new APIs are added: + Add an API that works like nfsd_file_acquire() but does not open the underlying file. The OPEN(CREATE) path can use this API when it already has an open file. + Add an API that is kin to dentry_open(). NFSD needs to create a file and grab an open "struct file *" atomically. The alloc_empty_file() has to be done before the inode create. If it fails (for example, because the NFS server has exceeded its max_files limit), we avoid creating the file and can still return an error to the NFS client. BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=382 Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: JianHong Yin <jiyin@redhat.com>
2022-05-19NFSD: Show state of courtesy client in client infoDai Ngo
Update client_info_show to show state of courtesy client and seconds since last renew. Reviewed-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-19NFSD: add support for lock conflict to courteous serverDai Ngo
This patch allows expired client with lock state to be in COURTESY state. Lock conflict with COURTESY client is resolved by the fs/lock code using the lm_lock_expirable and lm_expire_lock callback in the struct lock_manager_operations. If conflict client is in COURTESY state, set it to EXPIRABLE and schedule the laundromat to run immediately to expire the client. The callback lm_expire_lock waits for the laundromat to flush its work queue before returning to caller. Reviewed-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-19NFSD: move create/destroy of laundry_wq to init_nfsd and exit_nfsdDai Ngo
This patch moves create/destroy of laundry_wq from nfs4_state_start and nfs4_state_shutdown_net to init_nfsd and exit_nfsd to prevent the laundromat from being freed while a thread is processing a conflicting lock. Reviewed-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-19NFSD: add support for share reservation conflict to courteous serverDai Ngo
This patch allows expired client with open state to be in COURTESY state. Share/access conflict with COURTESY client is resolved by setting COURTESY client to EXPIRABLE state, schedule laundromat to run and returning nfserr_jukebox to the request client. Reviewed-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-05-19NFSD: add courteous server support for thread with only delegationDai Ngo
This patch provides courteous server support for delegation only. Only expired client with delegation but no conflict and no open or lock state is allowed to be in COURTESY state. Delegation conflict with COURTESY/EXPIRABLE client is resolved by setting it to EXPIRABLE, queue work for the laundromat and return delay to the caller. Conflict is resolved when the laudromat runs and expires the EXIRABLE client while the NFS client retries the OPEN request. Local thread request that gets conflict is doing the retry in _break_lease. Client in COURTESY or EXPIRABLE state is allowed to reconnect and continues to have access to its state. Access to the nfs4_client by the reconnecting thread and the laundromat is serialized via the client_lock. Reviewed-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-03-11NFSD: Fix nfsd_breaker_owns_lease() return valuesChuck Lever
These have been incorrect since the function was introduced. A proper kerneldoc comment is added since this function, though static, is part of an external interface. Reported-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-03-11NFSD: Clean up _lm_ operation namesChuck Lever
The common practice is to name function instances the same as the method names, but with a uniquifying prefix. Commit aef9583b234a ("NFSD: Get reference of lockowner when coping file_lock") missed this -- the new function names should both have been of the form "nfsd4_lm_*". Before more lock manager operations are added in NFSD, rename these two functions for consistency. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-28nfsd: nfsd4_setclientid_confirm mistakenly expires confirmed client.Dai Ngo
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>
2022-01-08nfsd: fix crash on COPY_NOTIFY with special stateidJ. Bruce Fields
RTM says "If the special ONE stateid is passed to nfs4_preprocess_stateid_op(), it returns status=0 but does not set *cstid. nfsd4_copy_notify() depends on stid being set if status=0, and thus can crash if the client sends the right COPY_NOTIFY RPC." RFC 7862 says "The cna_src_stateid MUST refer to either open or locking states provided earlier by the server. If it is invalid, then the operation MUST fail." The RFC doesn't specify an error, and the choice doesn't matter much as this is clearly illegal client behavior, but bad_stateid seems reasonable. Simplest is just to guarantee that nfs4_preprocess_stateid_op, called with non-NULL cstid, errors out if it can't return a stateid. Reported-by: rtm@csail.mit.edu Fixes: 624322f1adc5 ("NFSD add COPY_NOTIFY operation") Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Olga Kornievskaia <kolga@netapp.com> Tested-by: Olga Kornievskaia <kolga@netapp.com>
2022-01-08nfsd4: add refcount for nfsd4_blocked_lockVasily Averin
nbl allocated in nfsd4_lock can be released by a several ways: directly in nfsd4_lock(), via nfs4_laundromat(), via another nfs command RELEASE_LOCKOWNER or via nfsd4_callback. This structure should be refcounted to be used and released correctly in all these cases. Refcount is initialized to 1 during allocation and is incremented when nbl is added into nbl_list/nbl_lru lists. Usually nbl is linked into both lists together, so only one refcount is used for both lists. However nfsd4_lock() should keep in mind that nbl can be present in one of lists only. This can happen if nbl was handled already by nfs4_laundromat/nfsd4_callback/etc. Refcount is decremented if vfs_lock_file() returns FILE_LOCK_DEFERRED, because nbl can be handled already by nfs4_laundromat/nfsd4_callback/etc. Refcount is not changed in find_blocked_lock() because of it reuses counter released after removing nbl from lists. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08nfs: block notification on fs with its own ->lockJ. Bruce Fields
NFSv4.1 supports an optional lock notification feature which notifies the client when a lock comes available. (Normally NFSv4 clients just poll for locks if necessary.) To make that work, we need to request a blocking lock from the filesystem. We turned that off for NFS in commit f657f8eef3ff ("nfs: don't atempt blocking locks on nfs reexports") [sic] because it actually blocks the nfsd thread while waiting for the lock. Thanks to Vasily Averin for pointing out that NFS isn't the only filesystem with that problem. Any filesystem that leaves ->lock NULL will use posix_lock_file(), which does the right thing. Simplest is just to assume that any filesystem that defines its own ->lock is not safe to request a blocking lock from. So, this patch mostly reverts commit f657f8eef3ff ("nfs: don't atempt blocking locks on nfs reexports") [sic] and commit b840be2f00c0 ("lockd: don't attempt blocking locks on nfs reexports"), and instead uses a check of ->lock (Vasily's suggestion) to decide whether to support blocking lock notifications on a given filesystem. Also add a little documentation. Perhaps someday we could add back an export flag later to allow filesystems with "good" ->lock methods to support blocking lock notifications. Reported-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> [ cel: Description rewritten to address checkpatch nits ] [ cel: Fixed warning when SUNRPC debugging is disabled ] [ cel: Fixed NULL check ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Vasily Averin <vvs@virtuozzo.com>