Commit Graph

3695 Commits

Author SHA1 Message Date
Chuck Lever
14a6b65c83 NFSD: Skip sending CB_RECALL_ANY when the backchannel isn't up
commit 8a388c1fabeb6606e16467b23242416c0dbeffad upstream.

NFSD sends CB_RECALL_ANY to clients when the server is low on
memory or that client has a large number of delegations outstanding.

We've seen cases where NFSD attempts to send CB_RECALL_ANY requests
to disconnected clients, and gets confused. These calls never go
anywhere if a backchannel transport to the target client isn't
available. Before the server can send any backchannel operation, the
client has to connect first and then do a BIND_CONN_TO_SESSION.

This patch doesn't address the root cause of the confusion, but
there's no need to queue up these optional operations if they can't
go anywhere.

Fixes: 44df6f439a17 ("NFSD: add delegation reaper to react to low memory condition")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-10 14:33:43 +02:00
Li Lingfeng
d96587cc93 nfsd: put dl_stid if fail to queue dl_recall
commit 230ca758453c63bd38e4d9f4a21db698f7abada8 upstream.

Before calling nfsd4_run_cb to queue dl_recall to the callback_wq, we
increment the reference count of dl_stid.
We expect that after the corresponding work_struct is processed, the
reference count of dl_stid will be decremented through the callback
function nfsd4_cb_recall_release.
However, if the call to nfsd4_run_cb fails, the incremented reference
count of dl_stid will not be decremented correspondingly, leading to the
following nfs4_stid leak:
unreferenced object 0xffff88812067b578 (size 344):
  comm "nfsd", pid 2761, jiffies 4295044002 (age 5541.241s)
  hex dump (first 32 bytes):
    01 00 00 00 6b 6b 6b 6b b8 02 c0 e2 81 88 ff ff  ....kkkk........
    00 6b 6b 6b 6b 6b 6b 6b 00 00 00 00 ad 4e ad de  .kkkkkkk.....N..
  backtrace:
    kmem_cache_alloc+0x4b9/0x700
    nfsd4_process_open1+0x34/0x300
    nfsd4_open+0x2d1/0x9d0
    nfsd4_proc_compound+0x7a2/0xe30
    nfsd_dispatch+0x241/0x3e0
    svc_process_common+0x5d3/0xcc0
    svc_process+0x2a3/0x320
    nfsd+0x180/0x2e0
    kthread+0x199/0x1d0
    ret_from_fork+0x30/0x50
    ret_from_fork_asm+0x1b/0x30
unreferenced object 0xffff8881499f4d28 (size 368):
  comm "nfsd", pid 2761, jiffies 4295044005 (age 5541.239s)
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 30 4d 9f 49 81 88 ff ff  ........0M.I....
    30 4d 9f 49 81 88 ff ff 20 00 00 00 01 00 00 00  0M.I.... .......
  backtrace:
    kmem_cache_alloc+0x4b9/0x700
    nfs4_alloc_stid+0x29/0x210
    alloc_init_deleg+0x92/0x2e0
    nfs4_set_delegation+0x284/0xc00
    nfs4_open_delegation+0x216/0x3f0
    nfsd4_process_open2+0x2b3/0xee0
    nfsd4_open+0x770/0x9d0
    nfsd4_proc_compound+0x7a2/0xe30
    nfsd_dispatch+0x241/0x3e0
    svc_process_common+0x5d3/0xcc0
    svc_process+0x2a3/0x320
    nfsd+0x180/0x2e0
    kthread+0x199/0x1d0
    ret_from_fork+0x30/0x50
    ret_from_fork_asm+0x1b/0x30
Fix it by checking the result of nfsd4_run_cb and call nfs4_put_stid if
fail to queue dl_recall.

Cc: stable@vger.kernel.org
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.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>
2025-04-10 14:33:43 +02:00
Dai Ngo
38d345f612 NFSD: fix hang in nfsd4_shutdown_callback
commit 036ac2778f7b28885814c6fbc07e156ad1624d03 upstream.

If nfs4_client is in courtesy state then there is no point to send
the callback. This causes nfsd4_shutdown_callback to hang since
cl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP
notifies NFSD that the connection was dropped.

This patch modifies nfsd4_run_cb_work to skip the RPC call if
nfs4_client is in courtesy state.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Fixes: 66af257999 ("NFSD: add courteous server support for thread with only delegation")
Cc: stable@vger.kernel.org
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>
2025-02-21 13:49:56 +01:00
Li Lingfeng
2e59b2b687 nfsd: clear acl_access/acl_default after releasing them
commit 7faf14a7b0366f153284db0ad3347c457ea70136 upstream.

If getting acl_default fails, acl_access and acl_default will be released
simultaneously. However, acl_access will still retain a pointer pointing
to the released posix_acl, which will trigger a WARNING in
nfs3svc_release_getacl like this:

------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 26 PID: 3199 at lib/refcount.c:28
refcount_warn_saturate+0xb5/0x170
Modules linked in:
CPU: 26 UID: 0 PID: 3199 Comm: nfsd Not tainted
6.12.0-rc6-00079-g04ae226af01f-dirty #8
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
RIP: 0010:refcount_warn_saturate+0xb5/0x170
Code: cc cc 0f b6 1d b3 20 a5 03 80 fb 01 0f 87 65 48 d8 00 83 e3 01 75
e4 48 c7 c7 c0 3b 9b 85 c6 05 97 20 a5 03 01 e8 fb 3e 30 ff <0f> 0b eb
cd 0f b6 1d 8a3
RSP: 0018:ffffc90008637cd8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff83904fde
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88871ed36380
RBP: ffff888158beeb40 R08: 0000000000000001 R09: fffff520010c6f56
R10: ffffc90008637ab7 R11: 0000000000000001 R12: 0000000000000001
R13: ffff888140e77400 R14: ffff888140e77408 R15: ffffffff858b42c0
FS:  0000000000000000(0000) GS:ffff88871ed00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562384d32158 CR3: 000000055cc6a000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ? refcount_warn_saturate+0xb5/0x170
 ? __warn+0xa5/0x140
 ? refcount_warn_saturate+0xb5/0x170
 ? report_bug+0x1b1/0x1e0
 ? handle_bug+0x53/0xa0
 ? exc_invalid_op+0x17/0x40
 ? asm_exc_invalid_op+0x1a/0x20
 ? tick_nohz_tick_stopped+0x1e/0x40
 ? refcount_warn_saturate+0xb5/0x170
 ? refcount_warn_saturate+0xb5/0x170
 nfs3svc_release_getacl+0xc9/0xe0
 svc_process_common+0x5db/0xb60
 ? __pfx_svc_process_common+0x10/0x10
 ? __rcu_read_unlock+0x69/0xa0
 ? __pfx_nfsd_dispatch+0x10/0x10
 ? svc_xprt_received+0xa1/0x120
 ? xdr_init_decode+0x11d/0x190
 svc_process+0x2a7/0x330
 svc_handle_xprt+0x69d/0x940
 svc_recv+0x180/0x2d0
 nfsd+0x168/0x200
 ? __pfx_nfsd+0x10/0x10
 kthread+0x1a2/0x1e0
 ? kthread+0xf4/0x1e0
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x34/0x60
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Kernel panic - not syncing: kernel: panic_on_warn set ...

Clear acl_access/acl_default after posix_acl_release is called to prevent
UAF from being triggered.

Fixes: a257cdd0e2 ("[PATCH] NFSD: Add server support for NFSv3 ACLs.")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20241107014705.2509463-1-lilingfeng@huaweicloud.com/
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Rick Macklem <rmacklem@uoguelph.ca>
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>
2025-02-21 13:49:55 +01:00
Chuck Lever
386aca2053 NFSD: Reset cb_seq_status after NFS4ERR_DELAY
commit 961b4b5e86bf56a2e4b567f81682defa5cba957e upstream.

I noticed that once an NFSv4.1 callback operation gets a
NFS4ERR_DELAY status on CB_SEQUENCE and then the connection is lost,
the callback client loops, resending it indefinitely.

The switch arm in nfsd4_cb_sequence_done() that handles
NFS4ERR_DELAY uses rpc_restart_call() to rearm the RPC state machine
for the retransmit, but that path does not call the rpc_prepare_call
callback again. Thus cb_seq_status is set to -10008 by the first
NFS4ERR_DELAY result, but is never set back to 1 for the retransmits.

nfsd4_cb_sequence_done() thinks it's getting nothing but a
long series of CB_SEQUENCE NFS4ERR_DELAY replies.

Fixes: 7ba6cad6c8 ("nfsd: New helper nfsd4_cb_sequence_done() for processing more cb errors")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-21 13:49:25 +01:00
Youzhong Yang
400fb0e9c2 nfsd: add list_head nf_gc to struct nfsd_file
commit 8e6e2ffa6569a205f1805cbaeca143b556581da6 upstream.

nfsd_file_put() in one thread can race with another thread doing
garbage collection (running nfsd_file_gc() -> list_lru_walk() ->
nfsd_file_lru_cb()):

  * In nfsd_file_put(), nf->nf_ref is 1, so it tries to do nfsd_file_lru_add().
  * nfsd_file_lru_add() returns true (with NFSD_FILE_REFERENCED bit set)
  * garbage collector kicks in, nfsd_file_lru_cb() clears REFERENCED bit and
    returns LRU_ROTATE.
  * garbage collector kicks in again, nfsd_file_lru_cb() now decrements nf->nf_ref
    to 0, runs nfsd_file_unhash(), removes it from the LRU and adds to the dispose
    list [list_lru_isolate_move(lru, &nf->nf_lru, head)]
  * nfsd_file_put() detects NFSD_FILE_HASHED bit is cleared, so it tries to remove
    the 'nf' from the LRU [if (!nfsd_file_lru_remove(nf))]. The 'nf' has been added
    to the 'dispose' list by nfsd_file_lru_cb(), so nfsd_file_lru_remove(nf) simply
    treats it as part of the LRU and removes it, which leads to its removal from
    the 'dispose' list.
  * At this moment, 'nf' is unhashed with its nf_ref being 0, and not on the LRU.
    nfsd_file_put() continues its execution [if (refcount_dec_and_test(&nf->nf_ref))],
    as nf->nf_ref is already 0, nf->nf_ref is set to REFCOUNT_SATURATED, and the 'nf'
    gets no chance of being freed.

nfsd_file_put() can also race with nfsd_file_cond_queue():
  * In nfsd_file_put(), nf->nf_ref is 1, so it tries to do nfsd_file_lru_add().
  * nfsd_file_lru_add() sets REFERENCED bit and returns true.
  * Some userland application runs 'exportfs -f' or something like that, which triggers
    __nfsd_file_cache_purge() -> nfsd_file_cond_queue().
  * In nfsd_file_cond_queue(), it runs [if (!nfsd_file_unhash(nf))], unhash is done
    successfully.
  * nfsd_file_cond_queue() runs [if (!nfsd_file_get(nf))], now nf->nf_ref goes to 2.
  * nfsd_file_cond_queue() runs [if (nfsd_file_lru_remove(nf))], it succeeds.
  * nfsd_file_cond_queue() runs [if (refcount_sub_and_test(decrement, &nf->nf_ref))]
    (with "decrement" being 2), so the nf->nf_ref goes to 0, the 'nf' is added to the
    dispose list [list_add(&nf->nf_lru, dispose)]
  * nfsd_file_put() detects NFSD_FILE_HASHED bit is cleared, so it tries to remove
    the 'nf' from the LRU [if (!nfsd_file_lru_remove(nf))], although the 'nf' is not
    in the LRU, but it is linked in the 'dispose' list, nfsd_file_lru_remove() simply
    treats it as part of the LRU and removes it. This leads to its removal from
    the 'dispose' list!
  * Now nf->ref is 0, unhashed. nfsd_file_put() continues its execution and set
    nf->nf_ref to REFCOUNT_SATURATED.

As shown in the above analysis, using nf_lru for both the LRU list and dispose list
can cause the leaks. This patch adds a new list_head nf_gc in struct nfsd_file, and uses
it for the dispose list. This does not fix the nfsd_file leaking issue completely.

Signed-off-by: Youzhong Yang <youzhong@gmail.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>
2025-01-23 17:17:17 +01:00
Yang Erkun
36775f42e0 nfsd: cancel nfsd_shrinker_work using sync mode in nfs4_state_shutdown_net
commit d5ff2fb2e7167e9483846e34148e60c0c016a1f6 upstream.

In the normal case, when we excute `echo 0 > /proc/fs/nfsd/threads`, the
function `nfs4_state_destroy_net` in `nfs4_state_shutdown_net` will
release all resources related to the hashed `nfs4_client`. If the
`nfsd_client_shrinker` is running concurrently, the `expire_client`
function will first unhash this client and then destroy it. This can
lead to the following warning. Additionally, numerous use-after-free
errors may occur as well.

nfsd_client_shrinker         echo 0 > /proc/fs/nfsd/threads

expire_client                nfsd_shutdown_net
  unhash_client                ...
                               nfs4_state_shutdown_net
                                 /* won't wait shrinker exit */
  /*                             cancel_work(&nn->nfsd_shrinker_work)
   * nfsd_file for this          /* won't destroy unhashed client1 */
   * client1 still alive         nfs4_state_destroy_net
   */

                               nfsd_file_cache_shutdown
                                 /* trigger warning */
                                 kmem_cache_destroy(nfsd_file_slab)
                                 kmem_cache_destroy(nfsd_file_mark_slab)
  /* release nfsd_file and mark */
  __destroy_client

====================================================================
BUG nfsd_file (Not tainted): Objects remaining in nfsd_file on
__kmem_cache_shutdown()
--------------------------------------------------------------------
CPU: 4 UID: 0 PID: 764 Comm: sh Not tainted 6.12.0-rc3+ #1

 dump_stack_lvl+0x53/0x70
 slab_err+0xb0/0xf0
 __kmem_cache_shutdown+0x15c/0x310
 kmem_cache_destroy+0x66/0x160
 nfsd_file_cache_shutdown+0xac/0x210 [nfsd]
 nfsd_destroy_serv+0x251/0x2a0 [nfsd]
 nfsd_svc+0x125/0x1e0 [nfsd]
 write_threads+0x16a/0x2a0 [nfsd]
 nfsctl_transaction_write+0x74/0xa0 [nfsd]
 vfs_write+0x1a5/0x6d0
 ksys_write+0xc1/0x160
 do_syscall_64+0x5f/0x170
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

====================================================================
BUG nfsd_file_mark (Tainted: G    B   W         ): Objects remaining
nfsd_file_mark on __kmem_cache_shutdown()
--------------------------------------------------------------------

 dump_stack_lvl+0x53/0x70
 slab_err+0xb0/0xf0
 __kmem_cache_shutdown+0x15c/0x310
 kmem_cache_destroy+0x66/0x160
 nfsd_file_cache_shutdown+0xc8/0x210 [nfsd]
 nfsd_destroy_serv+0x251/0x2a0 [nfsd]
 nfsd_svc+0x125/0x1e0 [nfsd]
 write_threads+0x16a/0x2a0 [nfsd]
 nfsctl_transaction_write+0x74/0xa0 [nfsd]
 vfs_write+0x1a5/0x6d0
 ksys_write+0xc1/0x160
 do_syscall_64+0x5f/0x170
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

To resolve this issue, cancel `nfsd_shrinker_work` using synchronous
mode in nfs4_state_shutdown_net.

Fixes: 7c24fa225081 ("NFSD: replace delayed_work with work_struct for nfsd_client_shrinker")
Signed-off-by: Yang Erkun <yangerkun@huaweicloud.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>
2025-01-02 10:30:55 +01:00
NeilBrown
61ddaac44e nfsd: restore callback functionality for NFSv4.0
[ Upstream commit 7917f01a286ce01e9c085e24468421f596ee1a0c ]

A recent patch inadvertently broke callbacks for NFSv4.0.

In the 4.0 case we do not expect a session to be found but still need to
call setup_callback_client() which will not try to dereference it.

This patch moves the check for failure to find a session into the 4.1+
branch of setup_callback_client()

Fixes: 1e02c641c3a4 ("NFSD: Prevent NULL dereference in nfsd4_process_cb_update()")
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>
2025-01-02 10:30:48 +01:00
Yang Erkun
45abb68c94 nfsd: fix nfs4_openowner leak when concurrent nfsd4_open occur
commit 98100e88dd8865999dc6379a3356cd799795fe7b upstream.

The action force umount(umount -f) will attempt to kill all rpc_task even
umount operation may ultimately fail if some files remain open.
Consequently, if an action attempts to open a file, it can potentially
send two rpc_task to nfs server.

                   NFS CLIENT
thread1                             thread2
open("file")
...
nfs4_do_open
 _nfs4_do_open
  _nfs4_open_and_get_state
   _nfs4_proc_open
    nfs4_run_open_task
     /* rpc_task1 */
     rpc_run_task
     rpc_wait_for_completion_task

                                    umount -f
                                    nfs_umount_begin
                                     rpc_killall_tasks
                                      rpc_signal_task
     rpc_task1 been wakeup
     and return -512
 _nfs4_do_open // while loop
    ...
    nfs4_run_open_task
     /* rpc_task2 */
     rpc_run_task
     rpc_wait_for_completion_task

While processing an open request, nfsd will first attempt to find or
allocate an nfs4_openowner. If it finds an nfs4_openowner that is not
marked as NFS4_OO_CONFIRMED, this nfs4_openowner will released. Since
two rpc_task can attempt to open the same file simultaneously from the
client to server, and because two instances of nfsd can run
concurrently, this situation can lead to lots of memory leak.
Additionally, when we echo 0 to /proc/fs/nfsd/threads, warning will be
triggered.

                    NFS SERVER
nfsd1                  nfsd2       echo 0 > /proc/fs/nfsd/threads

nfsd4_open
 nfsd4_process_open1
  find_or_alloc_open_stateowner
   // alloc oo1, stateid1
                       nfsd4_open
                        nfsd4_process_open1
                        find_or_alloc_open_stateowner
                        // find oo1, without NFS4_OO_CONFIRMED
                         release_openowner
                          unhash_openowner_locked
                          list_del_init(&oo->oo_perclient)
                          // cannot find this oo
                          // from client, LEAK!!!
                         alloc_stateowner // alloc oo2

 nfsd4_process_open2
  init_open_stateid
  // associate oo1
  // with stateid1, stateid1 LEAK!!!
  nfs4_get_vfs_file
  // alloc nfsd_file1 and nfsd_file_mark1
  // all LEAK!!!

                         nfsd4_process_open2
                         ...

                                    write_threads
                                     ...
                                     nfsd_destroy_serv
                                      nfsd_shutdown_net
                                       nfs4_state_shutdown_net
                                        nfs4_state_destroy_net
                                         destroy_client
                                          __destroy_client
                                          // won't find oo1!!!
                                     nfsd_shutdown_generic
                                      nfsd_file_cache_shutdown
                                       kmem_cache_destroy
                                       for nfsd_file_slab
                                       and nfsd_file_mark_slab
                                       // bark since nfsd_file1
                                       // and nfsd_file_mark1
                                       // still alive

=======================================================================
BUG nfsd_file (Not tainted): Objects remaining in nfsd_file on
__kmem_cache_shutdown()
-----------------------------------------------------------------------

Slab 0xffd4000004438a80 objects=34 used=1 fp=0xff11000110e2ad28
flags=0x17ffffc0000240(workingset|head|node=0|zone=2|lastcpupid=0x1fffff)
CPU: 4 UID: 0 PID: 757 Comm: sh Not tainted 6.12.0-rc6+ #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x53/0x70
 slab_err+0xb0/0xf0
 __kmem_cache_shutdown+0x15c/0x310
 kmem_cache_destroy+0x66/0x160
 nfsd_file_cache_shutdown+0xac/0x210 [nfsd]
 nfsd_destroy_serv+0x251/0x2a0 [nfsd]
 nfsd_svc+0x125/0x1e0 [nfsd]
 write_threads+0x16a/0x2a0 [nfsd]
 nfsctl_transaction_write+0x74/0xa0 [nfsd]
 vfs_write+0x1ae/0x6d0
 ksys_write+0xc1/0x160
 do_syscall_64+0x5f/0x170
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Disabling lock debugging due to kernel taint
Object 0xff11000110e2ac38 @offset=3128
Allocated in nfsd_file_do_acquire+0x20f/0xa30 [nfsd] age=1635 cpu=3
pid=800
 nfsd_file_do_acquire+0x20f/0xa30 [nfsd]
 nfsd_file_acquire_opened+0x5f/0x90 [nfsd]
 nfs4_get_vfs_file+0x4c9/0x570 [nfsd]
 nfsd4_process_open2+0x713/0x1070 [nfsd]
 nfsd4_open+0x74b/0x8b0 [nfsd]
 nfsd4_proc_compound+0x70b/0xc20 [nfsd]
 nfsd_dispatch+0x1b4/0x3a0 [nfsd]
 svc_process_common+0x5b8/0xc50 [sunrpc]
 svc_process+0x2ab/0x3b0 [sunrpc]
 svc_handle_xprt+0x681/0xa20 [sunrpc]
 nfsd+0x183/0x220 [nfsd]
 kthread+0x199/0x1e0
 ret_from_fork+0x31/0x60
 ret_from_fork_asm+0x1a/0x30

Add nfs4_openowner_unhashed to help found unhashed nfs4_openowner, and
break nfsd4_open process to fix this problem.

Cc: stable@vger.kernel.org # v5.4+
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Yang Erkun <yangerkun@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-14 19:54:16 +01:00
Yang Erkun
7d8f7816be nfsd: make sure exp active before svc_export_show
commit be8f982c369c965faffa198b46060f8853e0f1f0 upstream.

The function `e_show` was called with protection from RCU. This only
ensures that `exp` will not be freed. Therefore, the reference count for
`exp` can drop to zero, which will trigger a refcount use-after-free
warning when `exp_get` is called. To resolve this issue, use
`cache_get_rcu` to ensure that `exp` remains active.

------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 3 PID: 819 at lib/refcount.c:25
refcount_warn_saturate+0xb1/0x120
CPU: 3 UID: 0 PID: 819 Comm: cat Not tainted 6.12.0-rc3+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
RIP: 0010:refcount_warn_saturate+0xb1/0x120
...
Call Trace:
 <TASK>
 e_show+0x20b/0x230 [nfsd]
 seq_read_iter+0x589/0x770
 seq_read+0x1e5/0x270
 vfs_read+0x125/0x530
 ksys_read+0xc1/0x160
 do_syscall_64+0x5f/0x170
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Fixes: bf18f163e8 ("NFSD: Using exp_get for export getting")
Cc: stable@vger.kernel.org # 4.20+
Signed-off-by: Yang Erkun <yangerkun@huawei.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>
2024-12-14 19:54:16 +01:00
Chuck Lever
de53c53051 NFSD: Prevent a potential integer overflow
commit 7f33b92e5b18e904a481e6e208486da43e4dc841 upstream.

If the tag length is >= U32_MAX - 3 then the "length + 4" addition
can result in an integer overflow. Address this by splitting the
decoding into several steps so that decode_cb_compound4res() does
not have to perform arithmetic on the unsafe length value.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Cc: stable@vger.kernel.org
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>
2024-12-14 19:54:06 +01:00
Chuck Lever
2ee368b447 NFSD: Fix nfsd4_shutdown_copy()
[ Upstream commit 62a8642ba00aa8ceb0a02ade942f5ec52e877c95 ]

nfsd4_shutdown_copy() is just this:

	while ((copy = nfsd4_get_copy(clp)) != NULL)
		nfsd4_stop_copy(copy);

nfsd4_get_copy() bumps @copy's reference count, preventing
nfsd4_stop_copy() from releasing @copy.

A while loop like this usually works by removing the first element
of the list, but neither nfsd4_get_copy() nor nfsd4_stop_copy()
alters the async_copies list.

Best I can tell, then, is that nfsd4_shutdown_copy() continues to
loop until other threads manage to remove all the items from this
list. The spinning loop blocks shutdown until these items are gone.

Possibly the reason we haven't seen this issue in the field is
because client_has_state() prevents __destroy_client() from calling
nfsd4_shutdown_copy() if there are any items on this list. In a
subsequent patch I plan to remove that restriction.

Fixes: e0639dc580 ("NFSD introduce async copy feature")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14 19:53:48 +01:00
Chuck Lever
03b72929f7 NFSD: Cap the number of bytes copied by nfs4_reset_recoverydir()
[ Upstream commit f64ea4af43161bb86ffc77e6aeb5bcf5c3229df0 ]

It's only current caller already length-checks the string, but let's
be safe.

Fixes: 0964a3d3f1 ("[PATCH] knfsd: nfsd4 reboot dirname fix")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14 19:53:47 +01:00
Chuck Lever
0c3b0e326f NFSD: Prevent NULL dereference in nfsd4_process_cb_update()
[ Upstream commit 1e02c641c3a43c88cecc08402000418e15578d38 ]

@ses is initialized to NULL. If __nfsd4_find_backchannel() finds no
available backchannel session, setup_callback_client() will try to
dereference @ses and segfault.

Fixes: dcbeaa68db ("nfsd4: allow backchannel recovery")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14 19:53:47 +01:00
Chuck Lever
949ee5d44d NFSD: Never decrement pending_async_copies on error
[ Upstream commit 8286f8b622990194207df9ab852e0f87c60d35e9 ]

The error flow in nfsd4_copy() calls cleanup_async_copy(), which
already decrements nn->pending_async_copies.

Reported-by: Olga Kornievskaia <okorniev@redhat.com>
Fixes: aadc3bbea163 ("NFSD: Limit the number of concurrent async COPY operations")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22 15:37:33 +01:00
Chuck Lever
c3074003fa NFSD: Initialize struct nfsd4_copy earlier
[ Upstream commit 63fab04cbd0f96191b6e5beedc3b643b01c15889 ]

Ensure the refcount and async_copies fields are initialized early.
cleanup_async_copy() will reference these fields if an error occurs
in nfsd4_copy(). If they are not correctly initialized, at the very
least, a refcount underflow occurs.

Reported-by: Olga Kornievskaia <okorniev@redhat.com>
Fixes: aadc3bbea163 ("NFSD: Limit the number of concurrent async COPY operations")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22 15:37:33 +01:00
Chuck Lever
7ea9260874 NFSD: Limit the number of concurrent async COPY operations
[ Upstream commit aadc3bbea163b6caaaebfdd2b6c4667fbc726752 ]

Nothing appears to limit the number of concurrent async COPY
operations that clients can start. In addition, AFAICT each async
COPY can copy an unlimited number of 4MB chunks, so can run for a
long time. Thus IMO async COPY can become a DoS vector.

Add a restriction mechanism that bounds the number of concurrent
background COPY operations. Start simple and try to be fair -- this
patch implements a per-namespace limit.

An async COPY request that occurs while this limit is exceeded gets
NFS4ERR_DELAY. The requesting client can choose to send the request
again after a delay or fall back to a traditional read/write style
copy.

If there is need to make the mechanism more sophisticated, we can
visit that in future patches.

Cc: stable@vger.kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Link: https://nvd.nist.gov/vuln/detail/CVE-2024-49974
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22 15:37:32 +01:00
Chuck Lever
2fd3f2f253 NFSD: Async COPY result needs to return a write verifier
[ Upstream commit 9ed666eba4e0a2bb8ffaa3739d830b64d4f2aaad ]

Currently, when NFSD handles an asynchronous COPY, it returns a
zero write verifier, relying on the subsequent CB_OFFLOAD callback
to pass the write verifier and a stable_how4 value to the client.

However, if the CB_OFFLOAD never arrives at the client (for example,
if a network partition occurs just as the server sends the
CB_OFFLOAD operation), the client will never receive this verifier.
Thus, if the client sends a follow-up COMMIT, there is no way for
the client to assess the COMMIT result.

The usual recovery for a missing CB_OFFLOAD is for the client to
send an OFFLOAD_STATUS operation, but that operation does not carry
a write verifier in its result. Neither does it carry a stable_how4
value, so the client /must/ send a COMMIT in this case -- which will
always fail because currently there's still no write verifier in the
COPY result.

Thus the server needs to return a normal write verifier in its COPY
result even if the COPY operation is to be performed asynchronously.

If the server recognizes the callback stateid in subsequent
OFFLOAD_STATUS operations, then obviously it has not restarted, and
the write verifier the client received in the COPY result is still
valid and can be used to assess a COMMIT of the copied data, if one
is needed.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: adjusted to apply to origin/linux-6.1.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22 15:37:32 +01:00
Dai Ngo
a86db75c53 NFSD: initialize copy->cp_clp early in nfsd4_copy for use by trace point
[ Upstream commit 15d1975b7279693d6f09398e0e2e31aca2310275 ]

Prepare for adding server copy trace points.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Tested-by: Chen Hanxiao <chenhx.fnst@fujitsu.com>
Stable-dep-of: 9ed666eba4e0 ("NFSD: Async COPY result needs to return a write verifier")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-22 15:37:32 +01:00
Chuck Lever
7cfc972acb NFSD: Mark filecache "down" if init fails
[ Upstream commit dc0d0f885aa422f621bc1c2124133eff566b0bc8 ]

NeilBrown says:
> The handling of NFSD_FILE_CACHE_UP is strange.  nfsd_file_cache_init()
> sets it, but doesn't clear it on failure.  So if nfsd_file_cache_init()
> fails for some reason, nfsd_file_cache_shutdown() would still try to
> clean up if it was called.

Reported-by: NeilBrown <neilb@suse.de>
Fixes: c7b824c3d0 ("NFSD: Replace the "init once" mechanism")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:22:18 +02:00
Chuck Lever
f07c20c6ee NFSD: Fix NFSv4's PUTPUBFH operation
commit 202f39039a11402dcbcd5fece8d9fa6be83f49ae upstream.

According to RFC 8881, all minor versions of NFSv4 support PUTPUBFH.

Replace the XDR decoder for PUTPUBFH with a "noop" since we no
longer want the minorversion check, and PUTPUBFH has no arguments to
decode. (Ideally nfsd4_decode_noop should really be called
nfsd4_decode_void).

PUTPUBFH should now behave just like PUTROOTFH.

Reported-by: Cedric Blancher <cedric.blancher@gmail.com>
Fixes: e1a90ebd8b ("NFSD: Combine decode operations for v4 and v4.1")
Cc: Dan Shelton <dan.f.shelton@gmail.com>
Cc: Roland Mainz <roland.mainz@nrubsig.org>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-17 15:21:58 +02:00
Li Lingfeng
6fe058502f nfsd: map the EBADMSG to nfserr_io to avoid warning
commit 340e61e44c1d2a15c42ec72ade9195ad525fd048 upstream.

Ext4 will throw -EBADMSG through ext4_readdir when a checksum error
occurs, resulting in the following WARNING.

Fix it by mapping EBADMSG to nfserr_io.

nfsd_buffered_readdir
 iterate_dir // -EBADMSG -74
  ext4_readdir // .iterate_shared
   ext4_dx_readdir
    ext4_htree_fill_tree
     htree_dirblock_to_tree
      ext4_read_dirblock
       __ext4_read_dirblock
        ext4_dirblock_csum_verify
         warn_no_space_for_csum
          __warn_no_space_for_csum
        return ERR_PTR(-EFSBADCRC) // -EBADMSG -74
 nfserrno // WARNING

[  161.115610] ------------[ cut here ]------------
[  161.116465] nfsd: non-standard errno: -74
[  161.117315] WARNING: CPU: 1 PID: 780 at fs/nfsd/nfsproc.c:878 nfserrno+0x9d/0xd0
[  161.118596] Modules linked in:
[  161.119243] CPU: 1 PID: 780 Comm: nfsd Not tainted 5.10.0-00014-g79679361fd5d #138
[  161.120684] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qe
mu.org 04/01/2014
[  161.123601] RIP: 0010:nfserrno+0x9d/0xd0
[  161.124676] Code: 0f 87 da 30 dd 00 83 e3 01 b8 00 00 00 05 75 d7 44 89 ee 48 c7 c7 c0 57 24 98 89 44 24 04 c6
 05 ce 2b 61 03 01 e8 99 20 d8 00 <0f> 0b 8b 44 24 04 eb b5 4c 89 e6 48 c7 c7 a0 6d a4 99 e8 cc 15 33
[  161.127797] RSP: 0018:ffffc90000e2f9c0 EFLAGS: 00010286
[  161.128794] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[  161.130089] RDX: 1ffff1103ee16f6d RSI: 0000000000000008 RDI: fffff520001c5f2a
[  161.131379] RBP: 0000000000000022 R08: 0000000000000001 R09: ffff8881f70c1827
[  161.132664] R10: ffffed103ee18304 R11: 0000000000000001 R12: 0000000000000021
[  161.133949] R13: 00000000ffffffb6 R14: ffff8881317c0000 R15: ffffc90000e2fbd8
[  161.135244] FS:  0000000000000000(0000) GS:ffff8881f7080000(0000) knlGS:0000000000000000
[  161.136695] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  161.137761] CR2: 00007fcaad70b348 CR3: 0000000144256006 CR4: 0000000000770ee0
[  161.139041] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  161.140291] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  161.141519] PKRU: 55555554
[  161.142076] Call Trace:
[  161.142575]  ? __warn+0x9b/0x140
[  161.143229]  ? nfserrno+0x9d/0xd0
[  161.143872]  ? report_bug+0x125/0x150
[  161.144595]  ? handle_bug+0x41/0x90
[  161.145284]  ? exc_invalid_op+0x14/0x70
[  161.146009]  ? asm_exc_invalid_op+0x12/0x20
[  161.146816]  ? nfserrno+0x9d/0xd0
[  161.147487]  nfsd_buffered_readdir+0x28b/0x2b0
[  161.148333]  ? nfsd4_encode_dirent_fattr+0x380/0x380
[  161.149258]  ? nfsd_buffered_filldir+0xf0/0xf0
[  161.150093]  ? wait_for_concurrent_writes+0x170/0x170
[  161.151004]  ? generic_file_llseek_size+0x48/0x160
[  161.151895]  nfsd_readdir+0x132/0x190
[  161.152606]  ? nfsd4_encode_dirent_fattr+0x380/0x380
[  161.153516]  ? nfsd_unlink+0x380/0x380
[  161.154256]  ? override_creds+0x45/0x60
[  161.155006]  nfsd4_encode_readdir+0x21a/0x3d0
[  161.155850]  ? nfsd4_encode_readlink+0x210/0x210
[  161.156731]  ? write_bytes_to_xdr_buf+0x97/0xe0
[  161.157598]  ? __write_bytes_to_xdr_buf+0xd0/0xd0
[  161.158494]  ? lock_downgrade+0x90/0x90
[  161.159232]  ? nfs4svc_decode_voidarg+0x10/0x10
[  161.160092]  nfsd4_encode_operation+0x15a/0x440
[  161.160959]  nfsd4_proc_compound+0x718/0xe90
[  161.161818]  nfsd_dispatch+0x18e/0x2c0
[  161.162586]  svc_process_common+0x786/0xc50
[  161.163403]  ? nfsd_svc+0x380/0x380
[  161.164137]  ? svc_printk+0x160/0x160
[  161.164846]  ? svc_xprt_do_enqueue.part.0+0x365/0x380
[  161.165808]  ? nfsd_svc+0x380/0x380
[  161.166523]  ? rcu_is_watching+0x23/0x40
[  161.167309]  svc_process+0x1a5/0x200
[  161.168019]  nfsd+0x1f5/0x380
[  161.168663]  ? nfsd_shutdown_threads+0x260/0x260
[  161.169554]  kthread+0x1c4/0x210
[  161.170224]  ? kthread_insert_work_sanity_check+0x80/0x80
[  161.171246]  ret_from_fork+0x1f/0x30

Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-17 15:21:58 +02:00
NeilBrown
137f672085 nfsd: fix delegation_blocked() to block correctly for at least 30 seconds
commit 45bb63ed20e02ae146336412889fe5450316a84f upstream.

The pair of bloom filtered used by delegation_blocked() was intended to
block delegations on given filehandles for between 30 and 60 seconds.  A
new filehandle would be recorded in the "new" bit set.  That would then
be switch to the "old" bit set between 0 and 30 seconds later, and it
would remain as the "old" bit set for 30 seconds.

Unfortunately the code intended to clear the old bit set once it reached
30 seconds old, preparing it to be the next new bit set, instead cleared
the *new* bit set before switching it to be the old bit set.  This means
that the "old" bit set is always empty and delegations are blocked
between 0 and 30 seconds.

This patch updates bd->new before clearing the set with that index,
instead of afterwards.

Reported-by: Olga Kornievskaia <okorniev@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 6282cd5655 ("NFSD: Don't hand out delegations for 30 seconds after recalling them.")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Benjamin Coddington <bcodding@redhat.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>
2024-10-17 15:21:57 +02:00
Li Lingfeng
84a563d136 nfsd: return -EINVAL when namelen is 0
[ Upstream commit 22451a16b7ab7debefce660672566be887db1637 ]

When we have a corrupted main.sqlite in /var/lib/nfs/nfsdcld/, it may
result in namelen being 0, which will cause memdup_user() to return
ZERO_SIZE_PTR.
When we access the name.data that has been assigned the value of
ZERO_SIZE_PTR in nfs4_client_to_reclaim(), null pointer dereference is
triggered.

[ T1205] ==================================================================
[ T1205] BUG: KASAN: null-ptr-deref in nfs4_client_to_reclaim+0xe9/0x260
[ T1205] Read of size 1 at addr 0000000000000010 by task nfsdcld/1205
[ T1205]
[ T1205] CPU: 11 PID: 1205 Comm: nfsdcld Not tainted 5.10.0-00003-g2c1423731b8d #406
[ T1205] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
[ T1205] Call Trace:
[ T1205]  dump_stack+0x9a/0xd0
[ T1205]  ? nfs4_client_to_reclaim+0xe9/0x260
[ T1205]  __kasan_report.cold+0x34/0x84
[ T1205]  ? nfs4_client_to_reclaim+0xe9/0x260
[ T1205]  kasan_report+0x3a/0x50
[ T1205]  nfs4_client_to_reclaim+0xe9/0x260
[ T1205]  ? nfsd4_release_lockowner+0x410/0x410
[ T1205]  cld_pipe_downcall+0x5ca/0x760
[ T1205]  ? nfsd4_cld_tracking_exit+0x1d0/0x1d0
[ T1205]  ? down_write_killable_nested+0x170/0x170
[ T1205]  ? avc_policy_seqno+0x28/0x40
[ T1205]  ? selinux_file_permission+0x1b4/0x1e0
[ T1205]  rpc_pipe_write+0x84/0xb0
[ T1205]  vfs_write+0x143/0x520
[ T1205]  ksys_write+0xc9/0x170
[ T1205]  ? __ia32_sys_read+0x50/0x50
[ T1205]  ? ktime_get_coarse_real_ts64+0xfe/0x110
[ T1205]  ? ktime_get_coarse_real_ts64+0xa2/0x110
[ T1205]  do_syscall_64+0x33/0x40
[ T1205]  entry_SYSCALL_64_after_hwframe+0x67/0xd1
[ T1205] RIP: 0033:0x7fdbdb761bc7
[ T1205] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 514
[ T1205] RSP: 002b:00007fff8c4b7248 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ T1205] RAX: ffffffffffffffda RBX: 000000000000042b RCX: 00007fdbdb761bc7
[ T1205] RDX: 000000000000042b RSI: 00007fff8c4b75f0 RDI: 0000000000000008
[ T1205] RBP: 00007fdbdb761bb0 R08: 0000000000000000 R09: 0000000000000001
[ T1205] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000042b
[ T1205] R13: 0000000000000008 R14: 00007fff8c4b75f0 R15: 0000000000000000
[ T1205] ==================================================================

Fix it by checking namelen.

Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Fixes: 74725959c3 ("nfsd: un-deprecate nfsdcld")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Scott Mayhew <smayhew@redhat.com>
Tested-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:21:08 +02:00
Guoqing Jiang
8182161731 nfsd: call cache_put if xdr_reserve_space returns NULL
[ Upstream commit d078cbf5c38de83bc31f83c47dcd2184c04a50c7 ]

If not enough buffer space available, but idmap_lookup has triggered
lookup_fn which calls cache_get and returns successfully. Then we
missed to call cache_put here which pairs with cache_get.

Fixes: ddd1ea5636 ("nfsd4: use xdr_reserve_space in attribute encoding")
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Reviwed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:21:08 +02:00
Jeff Layton
0deb526696 nfsd: fix refcount leak when file is unhashed after being found
[ Upstream commit 8a7926176378460e0d91e02b03f0ff20a8709a60 ]

If we wait_for_construction and find that the file is no longer hashed,
and we're going to retry the open, the old nfsd_file reference is
currently leaked. Put the reference before retrying.

Fixes: c6593366c0bf ("nfsd: don't kill nfsd_files because of lease break error")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Youzhong Yang <youzhong@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:21:05 +02:00
Jeff Layton
4a6d385e0c nfsd: remove unneeded EEXIST error check in nfsd_do_file_acquire
[ Upstream commit 81a95c2b1d605743220f28db04b8da13a65c4059 ]

Given that we do the search and insertion while holding the i_lock, I
don't think it's possible for us to get EEXIST here. Remove this case.

Fixes: c6593366c0bf ("nfsd: don't kill nfsd_files because of lease break error")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Youzhong Yang <youzhong@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:21:05 +02:00
Trond Myklebust
37a87b0518 nfsd: Fix a regression in nfsd_setattr()
[ Upstream commit 6412e44c40aaf8f1d7320b2099c5bdd6cb9126ac ]

Commit bb4d53d66e ("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: bb4d53d66e ("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 v6.1.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-29 17:30:53 +02:00
NeilBrown
3977ac0c22 nfsd: don't call locks_release_private() twice concurrently
[ 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: 47446d74f1 ("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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-29 17:30:53 +02:00
Jeff Layton
631e27be99 nfsd: drop the nfsd_put helper
[ 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-29 17:30:53 +02:00
NeilBrown
eeae04bcec nfsd: call nfsd_last_thread() before final nfsd_put()
[ 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: ec52361df9 ("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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-29 17:30:52 +02:00
NeilBrown
27cb298d60 NFSD: simplify error paths in nfsd_svc()
[ Upstream commit bf32075256e9dd9c6b736859e2c5813981339908 ]

The error paths in nfsd_svc() are needlessly complex and can result in a
final call to svc_put() without nfsd_last_thread() being called.  This
results in the listening sockets not being closed properly.

The per-netns setup provided by nfsd_startup_new() and removed by
nfsd_shutdown_net() is needed precisely when there are running threads.
So we don't need nfsd_up_before.  We don't need to know if it *was* up.
We only need to know if any threads are left.  If none are, then we must
call nfsd_shutdown_net().  But we don't need to do that explicitly as
nfsd_last_thread() does that for us.

So simply call nfsd_last_thread() before the last svc_put() if there are
no running threads.  That will always do the right thing.

Also discard:
 pr_info("nfsd: last server has exited, flushing export cache\n");
It may not be true if an attempt to start the first server failed, and
it isn't particularly helpful and it simply reports normal behaviour.

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-29 17:30:52 +02:00
NeilBrown
b5167e0021 nfsd: separate nfsd_last_thread() from nfsd_put()
[ 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-29 17:30:52 +02:00
NeilBrown
8862e33951 nfsd: Simplify code around svc_exit_thread() call in nfsd()
[ 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-29 17:30:52 +02:00
Josef Bacik
a2ba098587 nfsd: make svc_stat per-network namespace instead of global
[ Upstream commit 16fb9808ab2c99979f081987752abcbc5b092eac ]

The final bit of stats that is global is the rpc svc_stat.  Move this
into the nfsd_net struct and use that everywhere instead of the global
struct.  Remove the unused global struct.

Signed-off-by: Josef Bacik <josef@toxicpanda.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>
2024-08-19 06:00:05 +02:00
Josef Bacik
9509b6bca9 nfsd: remove nfsd_stats, make th_cnt a global counter
[ Upstream commit e41ee44cc6a473b1f414031782c3b4283d7f3e5f ]

This is the last global stat, take it out of the nfsd_stats struct and
make it a global part of nfsd, report it the same as always.

Signed-off-by: Josef Bacik <josef@toxicpanda.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>
2024-08-19 06:00:05 +02:00
Josef Bacik
099bf217b5 nfsd: make all of the nfsd stats per-network namespace
[ Upstream commit 4b14885411f74b2b0ce0eb2b39d0fffe54e5ca0d ]

We have a global set of counters that we modify for all of the nfsd
operations, but now that we're exposing these stats across all network
namespaces we need to make the stats also be per-network namespace.  We
already have some caching stats that are per-network namespace, so move
these definitions into the same counter and then adjust all the helpers
and users of these stats to provide the appropriate nfsd_net struct so
that the stats are maintained for the per-network namespace objects.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: adjusted to apply to v6.1.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:05 +02:00
Josef Bacik
10ece754df nfsd: expose /proc/net/sunrpc/nfsd in net namespaces
[ Upstream commit 93483ac5fec62cc1de166051b219d953bb5e4ef4 ]

We are running nfsd servers inside of containers with their own network
namespace, and we want to monitor these services using the stats found
in /proc.  However these are not exposed in the proc inside of the
container, so we have to bind mount the host /proc into our containers
to get at this information.

Separate out the stat counters init and the proc registration, and move
the proc registration into the pernet operations entry and exit points
so that these stats can be exposed inside of network namespaces.

This is an intermediate step, this just exposes the global counters in
the network namespace.  Subsequent patches will move these counters into
the per-network namespace container.

Signed-off-by: Josef Bacik <josef@toxicpanda.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>
2024-08-19 06:00:05 +02:00
Josef Bacik
546fbe74ce nfsd: rename NFSD_NET_* to NFSD_STATS_*
[ Upstream commit d98416cc2154053950610bb6880911e3dcbdf8c5 ]

We're going to merge the stats all into per network namespace in
subsequent patches, rename these nn counters to be consistent with the
rest of the stats.

Signed-off-by: Josef Bacik <josef@toxicpanda.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>
2024-08-19 06:00:05 +02:00
Josef Bacik
22f5194e38 sunrpc: remove ->pg_stats from svc_program
[ Upstream commit 3f6ef182f144dcc9a4d942f97b6a8ed969f13c95 ]

Now that this isn't used anywhere, remove it.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: adjusted to apply to v6.1.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:05 +02:00
Josef Bacik
94f2dc2667 sunrpc: pass in the sv_stats struct through svc_create_pooled
[ Upstream commit f094323867668d50124886ad884b665de7319537 ]

Since only one service actually reports the rpc stats there's not much
of a reason to have a pointer to it in the svc_program struct.  Adjust
the svc_create_pooled function to take the sv_stats as an argument and
pass the struct through there as desired instead of getting it from the
svc_program->pg_stats.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: adjusted to apply to v6.1.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:04 +02:00
Josef Bacik
4240c2f543 nfsd: stop setting ->pg_stats for unused stats
[ Upstream commit a2214ed588fb3c5b9824a21cff870482510372bb ]

A lot of places are setting a blank svc_stats in ->pg_stats and never
utilizing these stats.  Remove all of these extra structs as we're not
reporting these stats anywhere.

Signed-off-by: Josef Bacik <josef@toxicpanda.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>
2024-08-19 06:00:04 +02:00
Chuck Lever
64528ab5f2 NFSD: Fix frame size warning in svc_export_parse()
[ Upstream commit 6939ace1f22681fface7841cdbf34d3204cc94b5 ]

fs/nfsd/export.c: In function 'svc_export_parse':
fs/nfsd/export.c:737:1: warning: the frame size of 1040 bytes is larger than 1024 bytes [-Wframe-larger-than=]
    737 | }

On my systems, svc_export_parse() has a stack frame of over 800
bytes, not 1040, but nonetheless, it could do with some reduction.

When a struct svc_export is on the stack, it's a temporary structure
used as an argument, and not visible as an actual exported FS. No
need to reserve space for export_stats in such cases.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202310012359.YEw5IrK6-lkp@intel.com/
Cc: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Stable-dep-of: 4b14885411f7 ("nfsd: make all of the nfsd stats per-network namespace")
[ cel: adjusted to apply to v6.1.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:04 +02:00
Chuck Lever
0b4e84615b NFSD: Rewrite synopsis of nfsd_percpu_counters_init()
[ Upstream commit 5ec39944f874e1ecc09f624a70dfaa8ac3bf9d08 ]

In function ‘export_stats_init’,
    inlined from ‘svc_export_alloc’ at fs/nfsd/export.c:866:6:
fs/nfsd/export.c:337:16: warning: ‘nfsd_percpu_counters_init’ accessing 40 bytes in a region of size 0 [-Wstringop-overflow=]
  337 |         return nfsd_percpu_counters_init(&stats->counter, EXP_STATS_COUNTERS_NUM);
      |                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/nfsd/export.c:337:16: note: referencing argument 1 of type ‘struct percpu_counter[0]’
fs/nfsd/stats.h: In function ‘svc_export_alloc’:
fs/nfsd/stats.h:40:5: note: in a call to function ‘nfsd_percpu_counters_init’
   40 | int nfsd_percpu_counters_init(struct percpu_counter counters[], int num);
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~

Cc: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Stable-dep-of: 93483ac5fec6 ("nfsd: expose /proc/net/sunrpc/nfsd in net namespaces")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:04 +02:00
Chuck Lever
c80c42b876 NFSD: Refactor the duplicate reply cache shrinker
[ Upstream commit c135e1269f34dfdea4bd94c11060c83a3c0b3c12 ]

Avoid holding the bucket lock while freeing cache entries. This
change also caps the number of entries that are freed when the
shrinker calls to reduce the shrinker's impact on the cache's
effectiveness.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: adjusted to apply to v6.1.y -- this one might not be necessary ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:04 +02:00
Chuck Lever
3bee251d43 NFSD: Replace nfsd_prune_bucket()
[ Upstream commit a9507f6af1450ed26a4a36d979af518f5bb21e5d ]

Enable nfsd_prune_bucket() to drop the bucket lock while calling
kfree(). Use the same pattern that Jeff recently introduced in the
NFSD filecache.

A few percpu operations are moved outside the lock since they
temporarily disable local IRQs which is expensive and does not
need to be done while the lock is held.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Stable-dep-of: c135e1269f34 ("NFSD: Refactor the duplicate reply cache shrinker")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:04 +02:00
Chuck Lever
e9a6b3a309 NFSD: Rename nfsd_reply_cache_alloc()
[ Upstream commit ff0d169329768c1102b7b07eebe5a9839aa1c143 ]

For readability, rename to match the other helpers.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Stable-dep-of: 4b14885411f7 ("nfsd: make all of the nfsd stats per-network namespace")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:03 +02:00
Chuck Lever
f51da03782 NFSD: Refactor nfsd_reply_cache_free_locked()
[ Upstream commit 35308e7f0fc3942edc87d9c6dc78c4a096428957 ]

To reduce contention on the bucket locks, we must avoid calling
kfree() while each bucket lock is held.

Start by refactoring nfsd_reply_cache_free_locked() into a helper
that removes an entry from the bucket (and must therefore run under
the lock) and a second helper that frees the entry (which does not
need to hold the lock).

For readability, rename the helpers nfsd_cacherep_<verb>.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Stable-dep-of: a9507f6af145 ("NFSD: Replace nfsd_prune_bucket()")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:03 +02:00
Jeff Layton
66a178177b nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net
[ Upstream commit ed9ab7346e908496816cffdecd46932035f66e2e ]

Commit f5f9d4a314da ("nfsd: move reply cache initialization into nfsd
startup") moved the initialization of the reply cache into nfsd startup,
but didn't account for the stats counters, which can be accessed before
nfsd is ever started. The result can be a NULL pointer dereference when
someone accesses /proc/fs/nfsd/reply_cache_stats while nfsd is still
shut down.

This is a regression and a user-triggerable oops in the right situation:

- non-x86_64 arch
- /proc/fs/nfsd is mounted in the namespace
- nfsd is not started in the namespace
- unprivileged user calls "cat /proc/fs/nfsd/reply_cache_stats"

Although this is easy to trigger on some arches (like aarch64), on
x86_64, calling this_cpu_ptr(NULL) evidently returns a pointer to the
fixed_percpu_data. That struct looks just enough like a newly
initialized percpu var to allow nfsd_reply_cache_stats_show to access
it without Oopsing.

Move the initialization of the per-net+per-cpu reply-cache counters
back into nfsd_init_net, while leaving the rest of the reply cache
allocations to be done at nfsd startup time.

Kudos to Eirik who did most of the legwork to track this down.

Cc: stable@vger.kernel.org # v6.3+
Fixes: f5f9d4a314da ("nfsd: move reply cache initialization into nfsd startup")
Reported-and-tested-by: Eirik Fuller <efuller@redhat.com>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2215429
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Stable-dep-of: 4b14885411f7 ("nfsd: make all of the nfsd stats per-network namespace")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:03 +02:00
Jeff Layton
e7e571ed4e nfsd: move reply cache initialization into nfsd startup
[ Upstream commit f5f9d4a314da88c0a5faa6d168bf69081b7a25ae ]

There's no need to start the reply cache before nfsd is up and running,
and doing so means that we register a shrinker for every net namespace
instead of just the ones where nfsd is running.

Move it to the per-net nfsd startup instead.

Reported-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Stable-dep-of: ed9ab7346e90 ("nfsd: move init of percpu reply_cache_stats counters back to nfsd_init_net")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-19 06:00:03 +02:00