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2024-06-21nfsd: Fix a regression in nfsd_setattr()Trond Myklebust2-2/+8
[ Upstream commit 6412e44c40aaf8f1d7320b2099c5bdd6cb9126ac ] Commit bb4d53d66e4b ("NFSD: use (un)lock_inode instead of fh_(un)lock for file operations") broke the NFSv3 pre/post op attributes behaviour when doing a SETATTR rpc call by stripping out the calls to fh_fill_pre_attrs() and fh_fill_post_attrs(). Fixes: bb4d53d66e4b ("NFSD: use (un)lock_inode instead of fh_(un)lock for file operations") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: NeilBrown <neilb@suse.de> Message-ID: <20240216012451.22725-1-trondmy@kernel.org> [ cel: adjusted to apply to v5.10.y ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: don't call locks_release_private() twice concurrentlyNeilBrown1-1/+1
[ Upstream commit 05eda6e75773592760285e10ac86c56d683be17f ] It is possible for free_blocked_lock() to be called twice concurrently, once from nfsd4_lock() and once from nfsd4_release_lockowner() calling remove_blocked_locks(). This is why a kref was added. It is perfectly safe for locks_delete_block() and kref_put() to be called in parallel as they use locking or atomicity respectively as protection. However locks_release_private() has no locking. It is safe for it to be called twice sequentially, but not concurrently. This patch moves that call from free_blocked_lock() where it could race with itself, to free_nbl() where it cannot. This will slightly delay the freeing of private info or release of the owner - but not by much. It is arguably more natural for this freeing to happen in free_nbl() where the structure itself is freed. This bug was found by code inspection - it has not been seen in practice. Fixes: 47446d74f170 ("nfsd4: add refcount for nfsd4_blocked_lock") Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: don't take fi_lock in nfsd_break_deleg_cb()NeilBrown1-6/+5
[ Upstream commit 5ea9a7c5fe4149f165f0e3b624fe08df02b6c301 ] A recent change to check_for_locks() changed it to take ->flc_lock while holding ->fi_lock. This creates a lock inversion (reported by lockdep) because there is a case where ->fi_lock is taken while holding ->flc_lock. ->flc_lock is held across ->fl_lmops callbacks, and nfsd_break_deleg_cb() is one of those and does take ->fi_lock. However it doesn't need to. Prior to v4.17-rc1~110^2~22 ("nfsd: create a separate lease for each delegation") nfsd_break_deleg_cb() would walk the ->fi_delegations list and so needed the lock. Since then it doesn't walk the list and doesn't need the lock. Two actions are performed under the lock. One is to call nfsd_break_one_deleg which calls nfsd4_run_cb(). These doesn't act on the nfs4_file at all, so don't need the lock. The other is to set ->fi_had_conflict which is in the nfs4_file. This field is only ever set here (except when initialised to false) so there is no possible problem will multiple threads racing when setting it. The field is tested twice in nfs4_set_delegation(). The first test does not hold a lock and is documented as an opportunistic optimisation, so it doesn't impose any need to hold ->fi_lock while setting ->fi_had_conflict. The second test in nfs4_set_delegation() *is* make under ->fi_lock, so removing the locking when ->fi_had_conflict is set could make a change. The change could only be interesting if ->fi_had_conflict tested as false even though nfsd_break_one_deleg() ran before ->fi_lock was unlocked. i.e. while hash_delegation_locked() was running. As hash_delegation_lock() doesn't interact in any way with nfs4_run_cb() there can be no importance to this interaction. So this patch removes the locking from nfsd_break_one_deleg() and moves the final test on ->fi_had_conflict out of the locked region to make it clear that locking isn't important to the test. It is still tested *after* vfs_setlease() has succeeded. This might be significant and as vfs_setlease() takes ->flc_lock, and nfsd_break_one_deleg() is called under ->flc_lock this "after" is a true ordering provided by a spinlock. Fixes: edcf9725150e ("nfsd: fix RELEASE_LOCKOWNER") Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: fix RELEASE_LOCKOWNERNeilBrown1-11/+15
[ Upstream commit edcf9725150e42beeca42d085149f4c88fa97afd ] The test on so_count in nfsd4_release_lockowner() is nonsense and harmful. Revert to using check_for_locks(), changing that to not sleep. First: harmful. As is documented in the kdoc comment for nfsd4_release_lockowner(), the test on so_count can transiently return a false positive resulting in a return of NFS4ERR_LOCKS_HELD when in fact no locks are held. This is clearly a protocol violation and with the Linux NFS client it can cause incorrect behaviour. If RELEASE_LOCKOWNER is sent while some other thread is still processing a LOCK request which failed because, at the time that request was received, the given owner held a conflicting lock, then the nfsd thread processing that LOCK request can hold a reference (conflock) to the lock owner that causes nfsd4_release_lockowner() to return an incorrect error. The Linux NFS client ignores that NFS4ERR_LOCKS_HELD error because it never sends NFS4_RELEASE_LOCKOWNER without first releasing any locks, so it knows that the error is impossible. It assumes the lock owner was in fact released so it feels free to use the same lock owner identifier in some later locking request. When it does reuse a lock owner identifier for which a previous RELEASE failed, it will naturally use a lock_seqid of zero. However the server, which didn't release the lock owner, will expect a larger lock_seqid and so will respond with NFS4ERR_BAD_SEQID. So clearly it is harmful to allow a false positive, which testing so_count allows. The test is nonsense because ... well... it doesn't mean anything. so_count is the sum of three different counts. 1/ the set of states listed on so_stateids 2/ the set of active vfs locks owned by any of those states 3/ various transient counts such as for conflicting locks. When it is tested against '2' it is clear that one of these is the transient reference obtained by find_lockowner_str_locked(). It is not clear what the other one is expected to be. In practice, the count is often 2 because there is precisely one state on so_stateids. If there were more, this would fail. In my testing I see two circumstances when RELEASE_LOCKOWNER is called. In one case, CLOSE is called before RELEASE_LOCKOWNER. That results in all the lock states being removed, and so the lockowner being discarded (it is removed when there are no more references which usually happens when the lock state is discarded). When nfsd4_release_lockowner() finds that the lock owner doesn't exist, it returns success. The other case shows an so_count of '2' and precisely one state listed in so_stateid. It appears that the Linux client uses a separate lock owner for each file resulting in one lock state per lock owner, so this test on '2' is safe. For another client it might not be safe. So this patch changes check_for_locks() to use the (newish) find_any_file_locked() so that it doesn't take a reference on the nfs4_file and so never calls nfsd_file_put(), and so never sleeps. With this check is it safe to restore the use of check_for_locks() rather than testing so_count against the mysterious '2'. Fixes: ce3c4ad7f4ce ("NFSD: Fix possible sleep during nfsd4_release_lockowner()") Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org> Cc: stable@vger.kernel.org # v6.2+ Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: drop the nfsd_put helperJeff Layton2-21/+17
[ Upstream commit 64e6304169f1e1f078e7f0798033f80a7fb0ea46 ] It's not safe to call nfsd_put once nfsd_last_thread has been called, as that function will zero out the nn->nfsd_serv pointer. Drop the nfsd_put helper altogether and open-code the svc_put in its callers instead. That allows us to not be reliant on the value of that pointer when handling an error. Fixes: 2a501f55cd64 ("nfsd: call nfsd_last_thread() before final nfsd_put()") Reported-by: Zhi Li <yieli@redhat.com> Cc: NeilBrown <neilb@suse.de> Signed-off-by: Jeffrey Layton <jlayton@redhat.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: call nfsd_last_thread() before final nfsd_put()NeilBrown3-3/+9
[ Upstream commit 2a501f55cd641eb4d3c16a2eab0d678693fac663 ] If write_ports_addfd or write_ports_addxprt fail, they call nfsd_put() without calling nfsd_last_thread(). This leaves nn->nfsd_serv pointing to a structure that has been freed. So remove 'static' from nfsd_last_thread() and call it when the nfsd_serv is about to be destroyed. Fixes: ec52361df99b ("SUNRPC: stop using ->sv_nrthreads as a refcount") Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21NFSD: fix possible oops when nfsd/pool_stats is closed.NeilBrown1-2/+3
[ Upstream commit 88956eabfdea7d01d550535af120d4ef265b1d02 ] If /proc/fs/nfsd/pool_stats is open when the last nfsd thread exits, then when the file is closed a NULL pointer is dereferenced. This is because nfsd_pool_stats_release() assumes that the pointer to the svc_serv cannot become NULL while a reference is held. This used to be the case but a recent patch split nfsd_last_thread() out from nfsd_put(), and clearing the pointer is done in nfsd_last_thread(). This is easily reproduced by running rpc.nfsd 8 ; ( rpc.nfsd 0;true) < /proc/fs/nfsd/pool_stats Fortunately nfsd_pool_stats_release() has easy access to the svc_serv pointer, and so can call svc_put() on it directly. Fixes: 9f28a971ee9f ("nfsd: separate nfsd_last_thread() from nfsd_put()") Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: separate nfsd_last_thread() from nfsd_put()NeilBrown2-34/+25
[ Upstream commit 9f28a971ee9fdf1bf8ce8c88b103f483be610277 ] Now that the last nfsd thread is stopped by an explicit act of calling svc_set_num_threads() with a count of zero, we only have a limited number of places that can happen, and don't need to call nfsd_last_thread() in nfsd_put() So separate that out and call it at the two places where the number of threads is set to zero. Move the clearing of ->nfsd_serv and the call to svc_xprt_destroy_all() into nfsd_last_thread(), as they are really part of the same action. nfsd_put() is now a thin wrapper around svc_put(), so make it a static inline. nfsd_put() cannot be called after nfsd_last_thread(), so in a couple of places we have to use svc_put() instead. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: Simplify code around svc_exit_thread() call in nfsd()NeilBrown1-23/+0
[ Upstream commit 18e4cf915543257eae2925671934937163f5639b ] Previously a thread could exit asynchronously (due to a signal) so some care was needed to hold nfsd_mutex over the last svc_put() call. Now a thread can only exit when svc_set_num_threads() is called, and this is always called under nfsd_mutex. So no care is needed. Not only is the mutex held when a thread exits now, but the svc refcount is elevated, so the svc_put() in svc_exit_thread() will never be a final put, so the mutex isn't even needed at this point in the code. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: don't allow nfsd threads to be signalled.Chuck Lever3-25/+6
[ Upstream commit 3903902401451b1cd9d797a8c79769eb26ac7fe5 ] The original implementation of nfsd used signals to stop threads during shutdown. In Linux 2.3.46pre5 nfsd gained the ability to shutdown threads internally it if was asked to run "0" threads. After this user-space transitioned to using "rpc.nfsd 0" to stop nfsd and sending signals to threads was no longer an important part of the API. In commit 3ebdbe5203a8 ("SUNRPC: discard svo_setup and rename svc_set_num_threads_sync()") (v5.17-rc1~75^2~41) we finally removed the use of signals for stopping threads, using kthread_stop() instead. This patch makes the "obvious" next step and removes the ability to signal nfsd threads - or any svc threads. nfsd stops allowing signals and we don't check for their delivery any more. This will allow for some simplification in later patches. A change worth noting is in nfsd4_ssc_setup_dul(). There was previously a signal_pending() check which would only succeed when the thread was being shut down. It should really have tested kthread_should_stop() as well. Now it just does the latter, not the former. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org> [ cel: adjusted to apply to v5.10.y ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: Fix creation time serialization orderTavian Barnes1-5/+5
[ Upstream commit d7dbed457c2ef83709a2a2723a2d58de43623449 ] In nfsd4_encode_fattr(), TIME_CREATE was being written out after all other times. However, they should be written out in an order that matches the bit flags in bmval1, which in this case are #define FATTR4_WORD1_TIME_ACCESS (1UL << 15) #define FATTR4_WORD1_TIME_CREATE (1UL << 18) #define FATTR4_WORD1_TIME_DELTA (1UL << 19) #define FATTR4_WORD1_TIME_METADATA (1UL << 20) #define FATTR4_WORD1_TIME_MODIFY (1UL << 21) so TIME_CREATE should come second. I noticed this on a FreeBSD NFSv4.2 client, which supports creation times. On this client, file times were weirdly permuted. With this patch applied on the server, times looked normal on the client. Fixes: e377a3e698fb ("nfsd: Add support for the birth time attribute") Link: https://unix.stackexchange.com/q/749605/56202 Signed-off-by: Tavian Barnes <tavianator@tavianator.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>
2024-06-21NFSD: Add an nfsd4_encode_nfstime4() helperChuck Lever1-20/+26
[ Upstream commit 262176798b18b12fd8ab84c94cfece0a6a652476 ] Clean up: de-duplicate some common code. Reviewed-by: Jeff Layton <jlayton@kernel.org> Acked-by: Tom Talpey <tom@talpey.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21lockd: drop inappropriate svc_get() from locked_get()NeilBrown1-1/+0
[ Upstream commit 665e89ab7c5af1f2d260834c861a74b01a30f95f ] The below-mentioned patch was intended to simplify refcounting on the svc_serv used by locked. The goal was to only ever have a single reference from the single thread. To that end we dropped a call to lockd_start_svc() (except when creating thread) which would take a reference, and dropped the svc_put(serv) that would drop that reference. Unfortunately we didn't also remove the svc_get() from lockd_create_svc() in the case where the svc_serv already existed. So after the patch: - on the first call the svc_serv was allocated and the one reference was given to the thread, so there are no extra references - on subsequent calls svc_get() was called so there is now an extra reference. This is clearly not consistent. The inconsistency is also clear in the current code in lockd_get() takes *two* references, one on nlmsvc_serv and one by incrementing nlmsvc_users. This clearly does not match lockd_put(). So: drop that svc_get() from lockd_get() (which used to be in lockd_create_svc(). Reported-by: Ido Schimmel <idosch@idosch.org> Closes: https://lore.kernel.org/linux-nfs/ZHsI%2FH16VX9kJQX1@shredder/T/#u Fixes: b73a2972041b ("lockd: move lockd_start_svc() call into lockd_create_svc()") Signed-off-by: NeilBrown <neilb@suse.de> Tested-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: fix double fget() bug in __write_ports_addfd()Dan Carpenter1-6/+1
[ Upstream commit c034203b6a9dae6751ef4371c18cb77983e30c28 ] The bug here is that you cannot rely on getting the same socket from multiple calls to fget() because userspace can influence that. This is a kind of double fetch bug. The fix is to delete the svc_alien_sock() function and instead do the checking inside the svc_addsock() function. Fixes: 3064639423c4 ("nfsd: check passed socket's net matches NFSd superblock's one") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: NeilBrown <neilb@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: make a copy of struct iattr before calling notify_changeJeff Layton1-1/+9
[ Upstream commit d53d70084d27f56bcdf5074328f2c9ec861be596 ] notify_change can modify the iattr structure. In particular it can end up setting ATTR_MODE when ATTR_KILL_SUID is already set, causing a BUG() if the same iattr is passed to notify_change more than once. Make a copy of the struct iattr before calling notify_change. Reported-by: Zhi Li <yieli@redhat.com> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2207969 Tested-by: Zhi Li <yieli@redhat.com> Fixes: 34b91dda7124 ("NFSD: Make nfsd4_setattr() wait before returning NFS4ERR_DELAY") 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>
2024-06-21NFSD: Fix problem of COMMIT and NFS4ERR_DELAY in infinite loopDai Ngo1-2/+0
[ Upstream commit 147abcacee33781e75588869e944ddb07528a897 ] The following request sequence to the same file causes the NFS client and server getting into an infinite loop with COMMIT and NFS4ERR_DELAY: OPEN REMOVE WRITE COMMIT Problem reported by recall11, recall12, recall14, recall20, recall22, recall40, recall42, recall48, recall50 of nfstest suite. This patch restores the handling of race condition in nfsd_file_do_acquire with unlink to that prior of the regression. Fixes: ac3a2585f018 ("nfsd: rework refcounting in filecache") 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>
2024-06-21nfsd: simplify the delayed disposal list codeJeff Layton1-42/+22
[ Upstream commit 92e4a6733f922f0fef1d0995f7b2d0eaff86c7ea ] When queueing a dispose list to the appropriate "freeme" lists, it pointlessly queues the objects one at a time to an intermediate list. Remove a few helpers and just open code a list_move to make it more clear and efficient. Better document the resulting functions with kerneldoc comments. 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>
2024-06-21NFSD: Convert filecache to rhltableChuck Lever2-187/+133
[ Upstream commit c4c649ab413ba6a785b25f0edbb12f617c87db2a ] While we were converting the nfs4_file hashtable to use the kernel's resizable hashtable data structure, Neil Brown observed that the list variant (rhltable) would be better for managing nfsd_file items as well. The nfsd_file hash table will contain multiple entries for the same inode -- these should be kept together on a list. And, it could be possible for exotic or malicious client behavior to cause the hash table to resize itself on every insertion. A nice simplification is that rhltable_lookup() can return a list that contains only nfsd_file items that match a given inode, which enables us to eliminate specialized hash table helper functions and use the default functions provided by the rhashtable implementation). Since we are now storing nfsd_file items for the same inode on a single list, that effectively reduces the number of hash entries that have to be tracked in the hash table. The mininum bucket count is therefore lowered. Light testing with fstests generic/531 show no regressions. Suggested-by: Neil Brown <neilb@suse.de> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: allow reaping files still under writebackJeff Layton2-4/+17
[ Upstream commit dcb779fcd4ed5984ad15991d574943d12a8693d1 ] On most filesystems, there is no reason to delay reaping an nfsd_file just because its underlying inode is still under writeback. nfsd just relies on client activity or the local flusher threads to do writeback. The main exception is NFS, which flushes all of its dirty data on last close. Add a new EXPORT_OP_FLUSH_ON_CLOSE flag to allow filesystems to signal that they do this, and only skip closing files under writeback on such filesystems. Also, remove a redundant NULL file pointer check in nfsd_file_check_writeback, and clean up nfs's export op flag definitions. Signed-off-by: Jeff Layton <jlayton@kernel.org> Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com> [ cel: adjusted to apply to v5.10.y ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: update comment over __nfsd_file_cache_purgeJeff Layton1-1/+2
[ Upstream commit 972cc0e0924598cb293b919d39c848dc038b2c28 ] 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>
2024-06-21nfsd: don't take/put an extra reference when putting a fileJeff Layton1-3/+1
[ Upstream commit b2ff1bd71db2a1b193a6dde0845adcd69cbcf75e ] The last thing that filp_close does is an fput, so don't bother taking and putting the extra reference. 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>
2024-06-21nfsd: add some comments to nfsd_file_do_acquireJeff Layton1-0/+5
[ Upstream commit b680cb9b737331aad271feebbedafb865504e234 ] David Howells mentioned that he found this bit of code confusing, so sprinkle in some comments to clarify. Reported-by: David Howells <dhowells@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>
2024-06-21nfsd: don't kill nfsd_files because of lease break errorJeff Layton1-14/+15
[ Upstream commit c6593366c0bf222be9c7561354dfb921c611745e ] An error from break_lease is non-fatal, so we needn't destroy the nfsd_file in that case. Just put the reference like we normally would and return the error. 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>
2024-06-21nfsd: simplify test_bit return in NFSD_FILE_KEY_FULL comparatorJeff Layton1-1/+1
[ Upstream commit d69b8dbfd0866abc5ec84652cc1c10fc3d4d91ef ] test_bit returns bool, so we can just compare the result of that to the key->gc value without the "!!". 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>
2024-06-21nfsd: NFSD_FILE_KEY_INODE only needs to find GC'ed entriesJeff Layton1-0/+4
[ Upstream commit 6c31e4c98853a4ba47355ea151b36a77c42b7734 ] Since v4 files are expected to be long-lived, there's little value in closing them out of the cache when there is conflicting access. Change the comparator to also match the gc value in the key. Change both of the current users of that key to set the gc value in the key to "true". 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>
2024-06-21nfsd: don't open-code clear_and_wake_up_bitJeff Layton1-3/+1
[ Upstream commit b8bea9f6cdd7236c7c2238d022145e9b2f8aac22 ] 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>
2024-06-21nfsd: call op_release, even when op_func returns an errorJeff Layton1-6/+5
[ Upstream commit 15a8b55dbb1ba154d82627547c5761cac884d810 ] For ops with "trivial" replies, nfsd4_encode_operation will shortcut most of the encoding work and skip to just marshalling up the status. One of the things it skips is calling op_release. This could cause a memory leak in the layoutget codepath if there is an error at an inopportune time. Have the compound processing engine always call op_release, even when op_func sets an error in op->status. With this change, we also need nfsd4_block_get_device_info_scsi to set the gd_device pointer to NULL on error to avoid a double free. Reported-by: Zhi Li <yieli@redhat.com> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2181403 Fixes: 34b1744c91cc ("nfsd4: define ->op_release for compound ops") 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>
2024-06-21NFSD: Avoid calling OPDESC() with ops->opnum == OP_ILLEGALChuck Lever1-1/+3
[ Upstream commit 804d8e0a6e54427268790472781e03bc243f4ee3 ] OPDESC() simply indexes into nfsd4_ops[] by the op's operation number, without range checking that value. It assumes callers are careful to avoid calling it with an out-of-bounds opnum value. nfsd4_decode_compound() is not so careful, and can invoke OPDESC() with opnum set to OP_ILLEGAL, which is 10044 -- well beyond the end of nfsd4_ops[]. Reported-by: Jeff Layton <jlayton@kernel.org> Fixes: f4f9ef4a1b0a ("nfsd4: opdesc will be useful outside nfs4proc.c") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: don't replace page in rq_pages if it's a continuation of last pageJeff Layton1-1/+8
[ Upstream commit 27c934dd8832dd40fd34776f916dc201e18b319b ] The splice read calls nfsd_splice_actor to put the pages containing file data into the svc_rqst->rq_pages array. It's possible however to get a splice result that only has a partial page at the end, if (e.g.) the filesystem hands back a short read that doesn't cover the whole page. nfsd_splice_actor will plop the partial page into its rq_pages array and return. Then later, when nfsd_splice_actor is called again, the remainder of the page may end up being filled out. At this point, nfsd_splice_actor will put the page into the array _again_ corrupting the reply. If this is done enough times, rq_next_page will overrun the array and corrupt the trailing fields -- the rq_respages and rq_next_page pointers themselves. If we've already added the page to the array in the last pass, don't add it to the array a second time when dealing with a splice continuation. This was originally handled properly in nfsd_splice_actor, but commit 91e23b1c3982 ("NFSD: Clean up nfsd_splice_actor()") removed the check for it. Fixes: 91e23b1c3982 ("NFSD: Clean up nfsd_splice_actor()") Cc: Al Viro <viro@zeniv.linux.org.uk> Reported-by: Dario Lesca <d.lesca@solinos.it> Tested-by: David Critch <dcritch@redhat.com> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2150630 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>
2024-06-21lockd: set file_lock start and end when decoding nlm4 testargsJeff Layton2-9/+13
[ Upstream commit 7ff84910c66c9144cc0de9d9deed9fb84c03aff0 ] Commit 6930bcbfb6ce dropped the setting of the file_lock range when decoding a nlm_lock off the wire. This causes the client side grant callback to miss matching blocks and reject the lock, only to rerequest it 30s later. Add a helper function to set the file_lock range from the start and end values that the protocol uses, and have the nlm_lock decoder call that to set up the file_lock args properly. Fixes: 6930bcbfb6ce ("lockd: detect and reject lock arguments that overflow") Reported-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Tested-by: Amir Goldstein <amir73il@gmail.com> Cc: stable@vger.kernel.org #6.0 Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21NFSD: Protect against filesystem freezingChuck Lever1-0/+2
[ Upstream commit fd9a2e1d513823e840960cb3bc26d8b7749d4ac2 ] Flole observes this WARNING on occasion: [1210423.486503] WARNING: CPU: 8 PID: 1524732 at fs/ext4/ext4_jbd2.c:75 ext4_journal_check_start+0x68/0xb0 Reported-by: <flole@flole.de> Suggested-by: Jan Kara <jack@suse.cz> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217123 Fixes: 73da852e3831 ("nfsd: use vfs_iter_read/write") Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21NFSD: copy the whole verifier in nfsd_copy_write_verifierChuck Lever1-1/+1
[ Upstream commit 90d2175572470ba7f55da8447c72ddd4942923c4 ] Currently, we're only memcpy'ing the first __be32. Ensure we copy into both words. Fixes: 91d2e9b56cf5 ("NFSD: Clean up the nfsd_net::nfssvc_boot field") Reported-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: don't fsync nfsd_files on last closeJeff Layton2-63/+12
[ Upstream commit 4c475eee02375ade6e864f1db16976ba0d96a0a2 ] Most of the time, NFSv4 clients issue a COMMIT before the final CLOSE of an open stateid, so with NFSv4, the fsync in the nfsd_file_free path is usually a no-op and doesn't block. We have a customer running knfsd over very slow storage (XFS over Ceph RBD). They were using the "async" export option because performance was more important than data integrity for this application. That export option turns NFSv4 COMMIT calls into no-ops. Due to the fsync in this codepath however, their final CLOSE calls would still stall (since a CLOSE effectively became a COMMIT). I think this fsync is not strictly necessary. We only use that result to reset the write verifier. Instead of fsync'ing all of the data when we free an nfsd_file, we can just check for writeback errors when one is acquired and when it is freed. If the client never comes back, then it'll never see the error anyway and there is no point in resetting it. If an error occurs after the nfsd_file is removed from the cache but before the inode is evicted, then it will reset the write verifier on the next nfsd_file_acquire, (since there will be an unseen error). The only exception here is if something else opens and fsyncs the file during that window. Given that local applications work with this limitation today, I don't see that as an issue. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2166658 Fixes: ac3a2585f018 ("nfsd: rework refcounting in filecache") Reported-and-tested-by: Pierguido Lambri <plambri@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>
2024-06-21nfsd: fix courtesy client with deny mode handling in nfs4_upgrade_openJeff Layton1-10/+11
[ 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>
2024-06-21NFSD: fix problems with cleanup on errors in nfsd4_copyDai Ngo2-6/+11
[ 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>
2024-06-21nfsd: don't hand out delegation on setuid files being opened for writeJeff Layton1-0/+27
[ 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>
2024-06-21NFSD: fix leaked reference count of nfsd4_ssc_umount_itemDai Ngo1-4/+8
[ Upstream commit 34e8f9ec4c9ac235f917747b23a200a5e0ec857b ] The reference count of nfsd4_ssc_umount_item is not decremented on error conditions. This prevents the laundromat from unmounting the vfsmount of the source file. This patch decrements the reference count of nfsd4_ssc_umount_item on error. Fixes: f4e44b393389 ("NFSD: delay unmount source's export after inter-server copy completed.") 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>
2024-06-21nfsd: clean up potential nfsd_file refcount leaks in COPY codepathJeff Layton1-13/+10
[ Upstream commit 6ba434cb1a8d403ea9aad1b667c3ea3ad8b3191f ] There are two different flavors of the nfsd4_copy struct. One is embedded in the compound and is used directly in synchronous copies. The other is dynamically allocated, refcounted and tracked in the client struture. For the embedded one, the cleanup just involves releasing any nfsd_files held on its behalf. For the async one, the cleanup is a bit more involved, and we need to dequeue it from lists, unhash it, etc. There is at least one potential refcount leak in this code now. If the kthread_create call fails, then both the src and dst nfsd_files in the original nfsd4_copy object are leaked. The cleanup in this codepath is also sort of weird. In the async copy case, we'll have up to four nfsd_file references (src and dst for both flavors of copy structure). They are both put at the end of nfsd4_do_async_copy, even though the ones held on behalf of the embedded one outlive that structure. Change it so that we always clean up the nfsd_file refs held by the embedded copy structure before nfsd4_copy returns. Rework cleanup_async_copy to handle both inter and intra copies. Eliminate nfsd4_cleanup_intra_ssc since it now becomes a no-op. 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>
2024-06-21nfsd: allow nfsd_file_get to sanely handle a NULL pointerJeff Layton2-6/+3
[ Upstream commit 70f62231cdfd52357836733dd31db787e0412ab2 ] ...and remove some now-useless NULL pointer checks in its callers. Suggested-by: NeilBrown <neilb@suse.de> 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>
2024-06-21NFSD: enhance inter-server copy cleanupDai Ngo2-68/+45
[ Upstream commit df24ac7a2e3a9d0bc68f1756a880e50bfe4b4522 ] Currently nfsd4_setup_inter_ssc returns the vfsmount of the source server's export when the mount completes. After the copy is done nfsd4_cleanup_inter_ssc is called with the vfsmount of the source server and it searches nfsd_ssc_mount_list for a matching entry to do the clean up. The problems with this approach are (1) the need to search the nfsd_ssc_mount_list and (2) the code has to handle the case where the matching entry is not found which looks ugly. The enhancement is instead of nfsd4_setup_inter_ssc returning the vfsmount, it returns the nfsd4_ssc_umount_item which has the vfsmount embedded in it. When nfsd4_cleanup_inter_ssc is called it's passed with the nfsd4_ssc_umount_item directly to do the clean up so no searching is needed and there is no need to handle the 'not found' case. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> [ cel: adjusted whitespace and variable/function names ] Reviewed-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: don't destroy global nfs4_file table in per-net shutdownJeff Layton1-1/+1
[ Upstream commit 4102db175b5d884d133270fdbd0e59111ce688fc ] The nfs4_file table is global, so shutting it down when a containerized nfsd is shut down is wrong and can lead to double-frees. Tear down the nfs4_file_rhltable in nfs4_state_shutdown instead of nfs4_state_shutdown_net. Fixes: d47b295e8d76 ("NFSD: Use rhashtable for managing nfs4_file objects") Link: https://bugzilla.redhat.com/show_bug.cgi?id=2169017 Reported-by: JianHong Yin <jiyin@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>
2024-06-21nfsd: don't free files unconditionally in __nfsd_file_cache_purgeJeff Layton1-25/+36
[ Upstream commit 4bdbba54e9b1c769da8ded9abd209d765715e1d6 ] nfsd_file_cache_purge is called when the server is shutting down, in which case, tearing things down is generally fine, but it also gets called when the exports cache is flushed. Instead of walking the cache and freeing everything unconditionally, handle it the same as when we have a notification of conflicting access. Fixes: ac3a2585f018 ("nfsd: rework refcounting in filecache") Reported-by: Ruben Vestergaard <rubenv@drcmr.dk> Reported-by: Torkil Svensgaard <torkil@drcmr.dk> Reported-by: Shachar Kagan <skagan@nvidia.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Tested-by: Shachar Kagan <skagan@nvidia.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21NFSD: replace delayed_work with work_struct for nfsd_client_shrinkerDai Ngo2-5/+5
[ Upstream commit 7c24fa225081f31bc6da6a355c1ba801889ab29a ] Since nfsd4_state_shrinker_count always calls mod_delayed_work with 0 delay, we can replace delayed_work with work_struct to save some space and overhead. Also add the call to cancel_work after unregister the shrinker in nfs4_state_shutdown_net. 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>
2024-06-21NFSD: register/unregister of nfsd-client shrinker at nfsd startup/shutdown timeDai Ngo3-21/+14
[ Upstream commit f385f7d244134246f984975ed34cd75f77de479f ] Currently the nfsd-client shrinker is registered and unregistered at the time the nfsd module is loaded and unloaded. The problem with this is the shrinker is being registered before all of the relevant fields in nfsd_net are initialized when nfsd is started. This can lead to an oops when memory is low and the shrinker is called while nfsd is not running. This patch moves the register/unregister of nfsd-client shrinker from module load/unload time to nfsd startup/shutdown time. Fixes: 44df6f439a17 ("NFSD: add delegation reaper to react to low memory condition") Reported-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> [ cel: adjusted to apply without e33c267ab70d ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21NFSD: fix use-after-free in nfsd4_ssc_setup_dul()Xingyuan Mo1-0/+1
[ Upstream commit e6cf91b7b47ff82b624bdfe2fdcde32bb52e71dd ] If signal_pending() returns true, schedule_timeout() will not be executed, causing the waiting task to remain in the wait queue. Fixed by adding a call to finish_wait(), which ensures that the waiting task will always be removed from the wait queue. Fixes: f4e44b393389 ("NFSD: delay unmount source's export after inter-server copy completed.") Signed-off-by: Xingyuan Mo <hdthky0@gmail.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>
2024-06-21NFSD: Use set_bit(RQ_DROPME)Chuck Lever1-2/+2
[ Upstream commit 5304930dbae82d259bcf7e5611db7c81e7a42eff ] The premise that "Once an svc thread is scheduled and executing an RPC, no other processes will touch svc_rqst::rq_flags" is false. svc_xprt_enqueue() examines the RQ_BUSY flag in scheduled nfsd threads when determining which thread to wake up next. Fixes: 9315564747cb ("NFSD: Use only RQ_DROPME to signal the need to drop a reply") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21Revert "SUNRPC: Use RMW bitops in single-threaded hot paths"Chuck Lever2-5/+4
[ Upstream commit 7827c81f0248e3c2f40d438b020f3d222f002171 ] The premise that "Once an svc thread is scheduled and executing an RPC, no other processes will touch svc_rqst::rq_flags" is false. svc_xprt_enqueue() examines the RQ_BUSY flag in scheduled nfsd threads when determining which thread to wake up next. Found via KCSAN. Fixes: 28df0988815f ("SUNRPC: Use RMW bitops in single-threaded hot paths") Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21nfsd: fix handling of cached open files in nfsd4_open codepathJeff Layton4-71/+42
[ 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>
2024-06-21nfsd: rework refcounting in filecacheJeff Layton2-180/+189
[ Upstream commit ac3a2585f018f10039b4a856dcb122da88c1c1c9 ] The filecache refcounting is a bit non-standard for something searchable by RCU, in that we maintain a sentinel reference while it's hashed. This in turn requires that we have to do things differently in the "put" depending on whether its hashed, which we believe to have led to races. There are other problems in here too. nfsd_file_close_inode_sync can end up freeing an nfsd_file while there are still outstanding references to it, and there are a number of subtle ToC/ToU races. Rework the code so that the refcount is what drives the lifecycle. When the refcount goes to zero, then unhash and rcu free the object. A task searching for a nfsd_file is allowed to bump its refcount, but only if it's not already 0. Ensure that we don't make any other changes to it until a reference is held. With this change, the LRU carries a reference. Take special care to deal with it when removing an entry from the list, and ensure that we only repurpose the nf_lru list_head when the refcount is 0 to ensure exclusive access to it. 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>
2024-06-21NFSD: Avoid clashing function prototypesKees Cook1-255/+377
[ Upstream commit e78e274eb22d966258a3845acc71d3c5b8ee2ea8 ] When built with Control Flow Integrity, function prototypes between caller and function declaration must match. These mismatches are visible at compile time with the new -Wcast-function-type-strict in Clang[1]. There were 97 warnings produced by NFS. For example: fs/nfsd/nfs4xdr.c:2228:17: warning: cast from '__be32 (*)(struct nfsd4_compoundargs *, struct nfsd4_access *)' (aka 'unsigned int (*)(struct nfsd4_compoundargs *, struct nfsd4_access *)') to 'nfsd4_dec' (aka 'unsigned int (*)(struct nfsd4_compoundargs *, void *)') converts to incompatible function type [-Wcast-function-type-strict] [OP_ACCESS] = (nfsd4_dec)nfsd4_decode_access, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The enc/dec callbacks were defined as passing "void *" as the second argument, but were being implicitly cast to a new type. Replace the argument with union nfsd4_op_u, and perform explicit member selection in the function body. There are no resulting binary differences. Changes were made mechanically using the following Coccinelle script, with minor by-hand fixes for members that didn't already match their existing argument name: @find@ identifier func; type T, opsT; identifier ops, N; @@ opsT ops[] = { [N] = (T) func, }; @already_void@ identifier find.func; identifier name; @@ func(..., -void +union nfsd4_op_u *name) { ... } @proto depends on !already_void@ identifier find.func; type T; identifier name; position p; @@ func@p(..., T name ) { ... } @script:python get_member@ type_name << proto.T; member; @@ coccinelle.member = cocci.make_ident(type_name.split("_", 1)[1].split(' ',1)[0]) @convert@ identifier find.func; type proto.T; identifier proto.name; position proto.p; identifier get_member.member; @@ func@p(..., - T name + union nfsd4_op_u *u ) { + T name = &u->member; ... } @cast@ identifier find.func; type T, opsT; identifier ops, N; @@ opsT ops[] = { [N] = - (T) func, }; Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Jeff Layton <jlayton@kernel.org> Cc: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: linux-nfs@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>