Commit Graph

6919 Commits

Author SHA1 Message Date
Trond Myklebust 1a81dfc9d1 NFSv4/flexfiles: Fix handling of NFS level errors in I/O
[ Upstream commit 38074de35b ]

Allow the flexfiles error handling to recognise NFS level errors (as
opposed to RPC level errors) and handle them separately. The main
motivator is the NFSERR_PERM errors that get returned if the NFS client
connects to the data server through a port number that is lower than
1024. In that case, the client should disconnect and retry a READ on a
different data server, or it should retry a WRITE after reconnecting.

Reviewed-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Fixes: d67ae825a5 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:05:09 +02:00
Benjamin Coddington 864a54c124 NFSv4/pNFS: Fix a race to wake on NFS_LAYOUT_DRAIN
[ Upstream commit c017762874 ]

We found a few different systems hung up in writeback waiting on the same
page lock, and one task waiting on the NFS_LAYOUT_DRAIN bit in
pnfs_update_layout(), however the pnfs_layout_hdr's plh_outstanding count
was zero.

It seems most likely that this is another race between the waiter and waker
similar to commit ed0172af5d ("SUNRPC: Fix a race to wake a sync task").
Fix it up by applying the advised barrier.

Fixes: 880265c77a ("pNFS: Avoid a live lock condition in pnfs_update_layout()")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:04:45 +02:00
Kuniyuki Iwashima 3c94212b57 nfs: Clean up /proc/net/rpc/nfs when nfs_fs_proc_net_init() fails.
[ Upstream commit e8d6f3ab59 ]

syzbot reported a warning below [1] following a fault injection in
nfs_fs_proc_net_init(). [0]

When nfs_fs_proc_net_init() fails, /proc/net/rpc/nfs is not removed.

Later, rpc_proc_exit() tries to remove /proc/net/rpc, and the warning
is logged as the directory is not empty.

Let's handle the error of nfs_fs_proc_net_init() properly.

[0]:
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 UID: 0 PID: 6120 Comm: syz.2.27 Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
  dump_stack_lvl (lib/dump_stack.c:123)
 should_fail_ex (lib/fault-inject.c:73 lib/fault-inject.c:174)
 should_failslab (mm/failslab.c:46)
 kmem_cache_alloc_noprof (mm/slub.c:4178 mm/slub.c:4204)
 __proc_create (fs/proc/generic.c:427)
 proc_create_reg (fs/proc/generic.c:554)
 proc_create_net_data (fs/proc/proc_net.c:120)
 nfs_fs_proc_net_init (fs/nfs/client.c:1409)
 nfs_net_init (fs/nfs/inode.c:2600)
 ops_init (net/core/net_namespace.c:138)
 setup_net (net/core/net_namespace.c:443)
 copy_net_ns (net/core/net_namespace.c:576)
 create_new_namespaces (kernel/nsproxy.c:110)
 unshare_nsproxy_namespaces (kernel/nsproxy.c:218 (discriminator 4))
 ksys_unshare (kernel/fork.c:3123)
 __x64_sys_unshare (kernel/fork.c:3190)
 do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
 </TASK>

[1]:
remove_proc_entry: removing non-empty directory 'net/rpc', leaking at least 'nfs'
 WARNING: CPU: 1 PID: 6120 at fs/proc/generic.c:727 remove_proc_entry+0x45e/0x530 fs/proc/generic.c:727
Modules linked in:
CPU: 1 UID: 0 PID: 6120 Comm: syz.2.27 Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
 RIP: 0010:remove_proc_entry+0x45e/0x530 fs/proc/generic.c:727
Code: 3c 02 00 0f 85 85 00 00 00 48 8b 93 d8 00 00 00 4d 89 f0 4c 89 e9 48 c7 c6 40 ba a2 8b 48 c7 c7 60 b9 a2 8b e8 33 81 1d ff 90 <0f> 0b 90 90 e9 5f fe ff ff e8 04 69 5e ff 90 48 b8 00 00 00 00 00
RSP: 0018:ffffc90003637b08 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff88805f534140 RCX: ffffffff817a92c8
RDX: ffff88807da99e00 RSI: ffffffff817a92d5 RDI: 0000000000000001
RBP: ffff888033431ac0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffff888033431a00
R13: ffff888033431ae4 R14: ffff888033184724 R15: dffffc0000000000
FS:  0000555580328500(0000) GS:ffff888124a62000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f71733743e0 CR3: 000000007f618000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  sunrpc_exit_net+0x46/0x90 net/sunrpc/sunrpc_syms.c:76
  ops_exit_list net/core/net_namespace.c:200 [inline]
  ops_undo_list+0x2eb/0xab0 net/core/net_namespace.c:253
  setup_net+0x2e1/0x510 net/core/net_namespace.c:457
  copy_net_ns+0x2a6/0x5f0 net/core/net_namespace.c:574
  create_new_namespaces+0x3ea/0xa90 kernel/nsproxy.c:110
  unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:218
  ksys_unshare+0x45b/0xa40 kernel/fork.c:3121
  __do_sys_unshare kernel/fork.c:3192 [inline]
  __se_sys_unshare kernel/fork.c:3190 [inline]
  __x64_sys_unshare+0x31/0x40 kernel/fork.c:3190
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa1a6b8e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff3a090368 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fa1a6db5fa0 RCX: 00007fa1a6b8e929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000080
RBP: 00007fa1a6c10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa1a6db5fa0 R14: 00007fa1a6db5fa0 R15: 0000000000000001
 </TASK>

Fixes: d47151b79e ("nfs: expose /proc/net/sunrpc/nfs in net namespaces")
Reported-by: syzbot+a4cc4ac22daa4a71b87c@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=a4cc4ac22daa4a71b87c
Tested-by: syzbot+a4cc4ac22daa4a71b87c@syzkaller.appspotmail.com
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10 16:04:45 +02:00
Scott Mayhew 9453ce2dd6 NFSv4: xattr handlers should check for absent nfs filehandles
[ Upstream commit 6e9a2f8dbe ]

The nfs inodes for referral anchors that have not yet been followed have
their filehandles zeroed out.

Attempting to call getxattr() on one of these will cause the nfs client
to send a GETATTR to the nfs server with the preceding PUTFH sans
filehandle.  The server will reply NFS4ERR_NOFILEHANDLE, leading to -EIO
being returned to the application.

For example:

$ strace -e trace=getxattr getfattr -n system.nfs4_acl /mnt/t/ref
getxattr("/mnt/t/ref", "system.nfs4_acl", NULL, 0) = -1 EIO (Input/output error)
/mnt/t/ref: system.nfs4_acl: Input/output error
+++ exited with 1 +++

Have the xattr handlers return -ENODATA instead.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06 11:01:32 +02:00
Sagi Grimberg 7dd032d124 NFSv4.2: fix setattr caching of TIME_[MODIFY|ACCESS]_SET when timestamps are delegated
[ Upstream commit aba41e90aa ]

nfs_setattr will flush all pending writes before updating a file time
attributes. However when the client holds delegated timestamps, it can
update its timestamps locally as it is the authority for the file
times attributes. The client will later set the file attributes by
adding a setattr to the delegreturn compound updating the server time
attributes.

Fix nfs_setattr to avoid flushing pending writes when the file time
attributes are delegated and the mtime/atime are set to a fixed
timestamp (ATTR_[MODIFY|ACCESS]_SET. Also, when sending the setattr
procedure over the wire, we need to clear the correct attribute bits
from the bitmask.

I was able to measure a noticable speedup when measuring untar performance.
Test: $ time tar xzf ~/dir.tgz
Baseline: 1m13.072s
Patched: 0m49.038s

Which is more than 30% latency improvement.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06 11:01:32 +02:00
Olga Kornievskaia 871d1d7f37 NFSv4.2: fix listxattr to return selinux security label
[ Upstream commit 243fea1346 ]

Currently, when NFS is queried for all the labels present on the
file via a command example "getfattr -d -m . /mnt/testfile", it
does not return the security label. Yet when asked specifically for
the label (getfattr -n security.selinux) it will be returned.
Include the security label when all attributes are queried.

Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06 11:01:32 +02:00
Han Young 605daf6ae6 NFSv4: Always set NLINK even if the server doesn't support it
[ Upstream commit 3a3065352f ]

fattr4_numlinks is a recommended attribute, so the client should emulate
it even if the server doesn't support it. In decode_attr_nlink function
in nfs4xdr.c, nlink is initialized to 1. However, this default value
isn't set to the inode due to the check in nfs_fhget.

So if the server doesn't support numlinks, inode's nlink will be zero,
the mount will fail with error "Stale file handle". Set the nlink to 1
if the server doesn't support it.

Signed-off-by: Han Young <hanyang.tony@bytedance.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06 11:01:31 +02:00
Max Kellermann 5bf0b9eeb0 fs/nfs/read: fix double-unlock bug in nfs_return_empty_folio()
commit 4c10fa44bc upstream.

Sometimes, when a file was read while it was being truncated by
another NFS client, the kernel could deadlock because folio_unlock()
was called twice, and the second call would XOR back the `PG_locked`
flag.

Most of the time (depending on the timing of the truncation), nobody
notices the problem because folio_unlock() gets called three times,
which flips `PG_locked` back off:

 1. vfs_read, nfs_read_folio, ... nfs_read_add_folio,
    nfs_return_empty_folio
 2. vfs_read, nfs_read_folio, ... netfs_read_collection,
    netfs_unlock_abandoned_read_pages
 3. vfs_read, ... nfs_do_read_folio, nfs_read_add_folio,
    nfs_return_empty_folio

The problem is that nfs_read_add_folio() is not supposed to unlock the
folio if fscache is enabled, and a nfs_netfs_folio_unlock() check is
missing in nfs_return_empty_folio().

Rarely this leads to a warning in netfs_read_collection():

 ------------[ cut here ]------------
 R=0000031c: folio 10 is not locked
 WARNING: CPU: 0 PID: 29 at fs/netfs/read_collect.c:133 netfs_read_collection+0x7c0/0xf00
 [...]
 Workqueue: events_unbound netfs_read_collection_worker
 RIP: 0010:netfs_read_collection+0x7c0/0xf00
 [...]
 Call Trace:
  <TASK>
  netfs_read_collection_worker+0x67/0x80
  process_one_work+0x12e/0x2c0
  worker_thread+0x295/0x3a0

Most of the time, however, processes just get stuck forever in
folio_wait_bit_common(), waiting for `PG_locked` to disappear, which
never happens because nobody is really holding the folio lock.

Fixes: 000dbe0bec ("NFS: Convert buffered read paths to use netfs when fscache is enabled")
Cc: stable@vger.kernel.org
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-27 11:11:15 +01:00
Scott Mayhew 95c4322c2a NFSv4: Don't check for OPEN feature support in v4.1
commit 4d4832ed13 upstream.

fattr4_open_arguments is a v4.2 recommended attribute, so we shouldn't
be sending it to v4.1 servers.

Fixes: cb78f9b7d0 ("nfs: fix the fetch of FATTR4_OPEN_ARGUMENTS")
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org # 6.11+
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-27 11:11:15 +01:00
Li Lingfeng afa06f2605 nfs: ignore SB_RDONLY when remounting nfs
[ Upstream commit 80c4de6ab4 ]

In some scenarios, when mounting NFS, more than one superblock may be
created. The final superblock used is the last one created, but only the
first superblock carries the ro flag passed from user space. If a ro flag
is added to the superblock via remount, it will trigger the issue
described in Link[1].

Link[2] attempted to address this by marking the superblock as ro during
the initial mount. However, this introduced a new problem in scenarios
where multiple mount points share the same superblock:
[root@a ~]# mount /dev/sdb /mnt/sdb
[root@a ~]# echo "/mnt/sdb *(rw,no_root_squash)" > /etc/exports
[root@a ~]# echo "/mnt/sdb/test_dir2 *(ro,no_root_squash)" >> /etc/exports
[root@a ~]# systemctl restart nfs-server
[root@a ~]# mount -t nfs -o rw 127.0.0.1:/mnt/sdb/test_dir1 /mnt/test_mp1
[root@a ~]# mount | grep nfs4
127.0.0.1:/mnt/sdb/test_dir1 on /mnt/test_mp1 type nfs4 (rw,relatime,...
[root@a ~]# mount -t nfs -o ro 127.0.0.1:/mnt/sdb/test_dir2 /mnt/test_mp2
[root@a ~]# mount | grep nfs4
127.0.0.1:/mnt/sdb/test_dir1 on /mnt/test_mp1 type nfs4 (ro,relatime,...
127.0.0.1:/mnt/sdb/test_dir2 on /mnt/test_mp2 type nfs4 (ro,relatime,...
[root@a ~]#

When mounting the second NFS, the shared superblock is marked as ro,
causing the previous NFS mount to become read-only.

To resolve both issues, the ro flag is no longer applied to the superblock
during remount. Instead, the ro flag on the mount is used to control
whether the mount point is read-only.

Fixes: 281cad46b3 ("NFS: Create a submount rpc_op")
Link[1]: https://lore.kernel.org/all/20240604112636.236517-3-lilingfeng@huaweicloud.com/
Link[2]: https://lore.kernel.org/all/20241130035818.1459775-1-lilingfeng3@huawei.com/
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:32:08 +02:00
Li Lingfeng 877a3f1be3 nfs: clear SB_RDONLY before getting superblock
[ Upstream commit 8cd9b78594 ]

As described in the link, commit 52cb7f8f17 ("nfs: ignore SB_RDONLY when
mounting nfs") removed the check for the ro flag when determining whether
to share the superblock, which caused issues when mounting different
subdirectories under the same export directory via NFSv3. However, this
change did not affect NFSv4.

For NFSv3:
1) A single superblock is created for the initial mount.
2) When mounted read-only, this superblock carries the SB_RDONLY flag.
3) Before commit 52cb7f8f17 ("nfs: ignore SB_RDONLY when mounting nfs"):
Subsequent rw mounts would not share the existing ro superblock due to
flag mismatch, creating a new superblock without SB_RDONLY.
After the commit:
  The SB_RDONLY flag is ignored during superblock comparison, and this leads
  to sharing the existing superblock even for rw mounts.
  Ultimately results in write operations being rejected at the VFS layer.

For NFSv4:
1) Multiple superblocks are created and the last one will be kept.
2) The actually used superblock for ro mounts doesn't carry SB_RDONLY flag.
Therefore, commit 52cb7f8f17 doesn't affect NFSv4 mounts.

Clear SB_RDONLY before getting superblock when NFS_MOUNT_UNSHARED is not
set to fix it.

Fixes: 52cb7f8f17 ("nfs: ignore SB_RDONLY when mounting nfs")
Closes: https://lore.kernel.org/all/12d7ea53-1202-4e21-a7ef-431c94758ce5@app.fastmail.com/T/
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:32:08 +02:00
Trond Myklebust c7ce21b85a NFS: Avoid flushing data while holding directory locks in nfs_rename()
[ Upstream commit dcd21b609d ]

The Linux client assumes that all filehandles are non-volatile for
renames within the same directory (otherwise sillyrename cannot work).
However, the existence of the Linux 'subtree_check' export option has
meant that nfs_rename() has always assumed it needs to flush writes
before attempting to rename.

Since NFSv4 does allow the client to query whether or not the server
exhibits this behaviour, and since knfsd does actually set the
appropriate flag when 'subtree_check' is enabled on an export, it
should be OK to optimise away the write flushing behaviour in the cases
where it is clearly not needed.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04 14:43:53 +02:00
Jeff Layton 16ed9db158 nfs: don't share pNFS DS connections between net namespaces
[ Upstream commit 6b9785dc8b ]

Currently, different NFS clients can share the same DS connections, even
when they are in different net namespaces. If a containerized client
creates a DS connection, another container can find and use it. When the
first client exits, the connection will close which can lead to stalls
in other clients.

Add a net namespace pointer to struct nfs4_pnfs_ds, and compare those
value to the caller's netns in _data_server_lookup_locked() when
searching for a nfs4_pnfs_ds to match.

Reported-by: Omar Sandoval <osandov@osandov.com>
Reported-by: Sargun Dillon <sargun@sargun.me>
Closes: https://lore.kernel.org/linux-nfs/Z_ArpQC_vREh_hEA@telecaster/
Tested-by: Sargun Dillon <sargun@sargun.me>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Link: https://lore.kernel.org/r/20250410-nfs-ds-netns-v2-1-f80b7979ba80@kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-04 14:43:52 +02:00
Trond Myklebust 1630224189 pNFS/flexfiles: Report ENETDOWN as a connection error
[ Upstream commit aa42add73c ]

If the client should see an ENETDOWN when trying to connect to the data
server, it might still be able to talk to the metadata server through
another NIC. If so, report the error.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29 11:02:08 +02:00
Trond Myklebust 71e07bb155 NFSv4: Treat ENETUNREACH errors as fatal for state recovery
[ Upstream commit 0af5fb5ed3 ]

If a containerised process is killed and causes an ENETUNREACH or
ENETDOWN error to be propagated to the state manager, then mark the
nfs_client as being dead so that we don't loop in functions that are
expecting recovery to succeed.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29 11:02:06 +02:00
Trond Myklebust ac83bf58f6 NFS: Don't allow waiting for exiting tasks
[ Upstream commit 8d3ca33102 ]

Once a task calls exit_signals() it can no longer be signalled. So do
not allow it to do killable waits.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29 11:02:03 +02:00
Trond Myklebust 46a47dc10f NFSv4: Check for delegation validity in nfs_start_delegation_return_locked()
[ Upstream commit 9e8f324bd4 ]

Check that the delegation is still attached after taking the spin lock
in nfs_start_delegation_return_locked().

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29 11:02:03 +02:00
Trond Myklebust 1533677267 NFSv4/pnfs: Reset the layout state after a layoutreturn
[ Upstream commit 6d6d7f91cc ]

If there are still layout segments in the layout plh_return_lsegs list
after a layout return, we should be resetting the state to ensure they
eventually get returned as well.

Fixes: 68f744797e ("pNFS: Do not free layout segments that are marked for return")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-22 14:29:44 +02:00
Li Lingfeng da824f1271 nfs: handle failure of nfs_get_lock_context in unlock path
[ Upstream commit c457dc1ec7 ]

When memory is insufficient, the allocation of nfs_lock_context in
nfs_get_lock_context() fails and returns -ENOMEM. If we mistakenly treat
an nfs4_unlockdata structure (whose l_ctx member has been set to -ENOMEM)
as valid and proceed to execute rpc_run_task(), this will trigger a NULL
pointer dereference in nfs4_locku_prepare. For example:

BUG: kernel NULL pointer dereference, address: 000000000000000c
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP PTI
CPU: 15 UID: 0 PID: 12 Comm: kworker/u64:0 Not tainted 6.15.0-rc2-dirty #60
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40
Workqueue: rpciod rpc_async_schedule
RIP: 0010:nfs4_locku_prepare+0x35/0xc2
Code: 89 f2 48 89 fd 48 c7 c7 68 69 ef b5 53 48 8b 8e 90 00 00 00 48 89 f3
RSP: 0018:ffffbbafc006bdb8 EFLAGS: 00010246
RAX: 000000000000004b RBX: ffff9b964fc1fa00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: fffffffffffffff4 RDI: ffff9ba53fddbf40
RBP: ffff9ba539934000 R08: 0000000000000000 R09: ffffbbafc006bc38
R10: ffffffffb6b689c8 R11: 0000000000000003 R12: ffff9ba539934030
R13: 0000000000000001 R14: 0000000004248060 R15: ffffffffb56d1c30
FS: 0000000000000000(0000) GS:ffff9ba5881f0000(0000) knlGS:00000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000000c CR3: 000000093f244000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __rpc_execute+0xbc/0x480
 rpc_async_schedule+0x2f/0x40
 process_one_work+0x232/0x5d0
 worker_thread+0x1da/0x3d0
 ? __pfx_worker_thread+0x10/0x10
 kthread+0x10d/0x240
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x34/0x50
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Modules linked in:
CR2: 000000000000000c
---[ end trace 0000000000000000 ]---

Free the allocated nfs4_unlockdata when nfs_get_lock_context() fails and
return NULL to terminate subsequent rpc_run_task, preventing NULL pointer
dereference.

Fixes: f30cb757f6 ("NFS: Always wait for I/O completion before unlock")
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20250417072508.3850532-1-lilingfeng3@huawei.com
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-22 14:29:38 +02:00
Eric Biggers 33c0f51f1a nfs: add missing selections of CONFIG_CRC32
[ Upstream commit cd35b6cb46 ]

nfs.ko, nfsd.ko, and lockd.ko all use crc32_le(), which is available
only when CONFIG_CRC32 is enabled.  But the only NFS kconfig option that
selected CONFIG_CRC32 was CONFIG_NFS_DEBUG, which is client-specific and
did not actually guard the use of crc32_le() even on the client.

The code worked around this bug by only actually calling crc32_le() when
CONFIG_CRC32 is built-in, instead hard-coding '0' in other cases.  This
avoided randconfig build errors, and in real kernels the fallback code
was unlikely to be reached since CONFIG_CRC32 is 'default y'.  But, this
really needs to just be done properly, especially now that I'm planning
to update CONFIG_CRC32 to not be 'default y'.

Therefore, make CONFIG_NFS_FS, CONFIG_NFSD, and CONFIG_LOCKD select
CONFIG_CRC32.  Then remove the fallback code that becomes unnecessary,
as well as the selection of CONFIG_CRC32 from CONFIG_NFS_DEBUG.

Fixes: 1264a2f053 ("NFS: refactor code for calculating the crc32 hash of a filehandle")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-25 10:47:50 +02:00
Dan Carpenter eb532ac40d nfs: Add missing release on error in nfs_lock_and_join_requests()
[ Upstream commit 8e5419d654 ]

Call nfs_release_request() on this error path before returning.

Fixes: c3f2235782 ("nfs: fold nfs_folio_find_and_lock_request into nfs_lock_and_join_requests")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/3aaaa3d5-1c8a-41e4-98c7-717801ddd171@stanley.mountain
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:28 +02:00
Trond Myklebust 81270dd796 NFS: Shut down the nfs_client only after all the superblocks
[ Upstream commit 2d3e998a0b ]

The nfs_client manages state for all the superblocks in the
"cl_superblocks" list, so it must not be shut down until all of them are
gone.

Fixes: 7d3e26a054 ("NFS: Cancel all existing RPC tasks when shutdown")
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:26 +02:00
NeilBrown ca27c16539 NFS: fix open_owner_id_maxsz and related fields.
[ Upstream commit 43502f6e8d ]

A recent change increased the size of an NFSv4 open owner, but didn't
increase the corresponding max_sz defines.  This is not know to have
caused failure, but should be fixed.

This patch also fixes some relates _maxsz fields that are wrong.

Note that the XXX_owner_id_maxsz values now are only the size of the id
and do NOT include the len field that will always preceed the id in xdr
encoding.  I think this is clearer.

Reported-by: David Disseldorp <ddiss@suse.com>
Fixes: d98f722725 ("nfs: simplify and guarantee owner uniqueness.")
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:24 +02:00
Trond Myklebust 46117472a2 NFSv4: Avoid unnecessary scans of filesystems for delayed delegations
[ Upstream commit e767b59e29 ]

The amount of looping through the list of delegations is occasionally
leading to soft lockups. If the state manager was asked to manage the
delayed return of delegations, then only scan those filesystems
containing delegations that were marked as being delayed.

Fixes: be20037725 ("NFSv4: Fix delegation return in cases where we have to retry")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:24 +02:00
Trond Myklebust 8765bc2638 NFSv4: Avoid unnecessary scans of filesystems for expired delegations
[ Upstream commit f163aa81a7 ]

The amount of looping through the list of delegations is occasionally
leading to soft lockups.  If the state manager was asked to reap the
expired delegations, it should scan only those filesystems that hold
delegations that need to be reaped.

Fixes: 7f156ef0bf ("NFSv4: Clean up nfs_delegation_reap_expired()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:24 +02:00
Trond Myklebust ac8be75a7d NFSv4: Avoid unnecessary scans of filesystems for returning delegations
[ Upstream commit 35a566a24e ]

The amount of looping through the list of delegations is occasionally
leading to soft lockups. If the state manager was asked to return
delegations asynchronously, it should only scan those filesystems that
hold delegations that need to be returned.

Fixes: af3b61bf61 ("NFSv4: Clean up nfs_client_return_marked_delegations()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:24 +02:00
Trond Myklebust 4595beb5fe NFSv4: Don't trigger uneccessary scans for return-on-close delegations
[ Upstream commit 47acca884f ]

The amount of looping through the list of delegations is occasionally
leading to soft lockups. Avoid at least some loops by not requiring the
NFSv4 state manager to scan for delegations that are marked for
return-on-close. Instead, either mark them for immediate return (if
possible) or else leave it up to nfs4_inode_return_delegation_on_close()
to return them once the file is closed by the application.

Fixes: b757144fd7 ("NFSv4: Be less aggressive about returning delegations for open files")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:24 +02:00
Mike Snitzer 5ae31c54cf NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback
commit ce6d9c1c2b upstream.

Add PF_KCOMPACTD flag and current_is_kcompactd() helper to check for it so
nfs_release_folio() can skip calling nfs_wb_folio() from kcompactd.

Otherwise NFS can deadlock waiting for kcompactd enduced writeback which
recurses back to NFS (which triggers writeback to NFSD via NFS loopback
mount on the same host, NFSD blocks waiting for XFS's call to
__filemap_get_folio):

6070.550357] INFO: task kcompactd0:58 blocked for more than 4435 seconds.

{---
[58] "kcompactd0"
[<0>] folio_wait_bit+0xe8/0x200
[<0>] folio_wait_writeback+0x2b/0x80
[<0>] nfs_wb_folio+0x80/0x1b0 [nfs]
[<0>] nfs_release_folio+0x68/0x130 [nfs]
[<0>] split_huge_page_to_list_to_order+0x362/0x840
[<0>] migrate_pages_batch+0x43d/0xb90
[<0>] migrate_pages_sync+0x9a/0x240
[<0>] migrate_pages+0x93c/0x9f0
[<0>] compact_zone+0x8e2/0x1030
[<0>] compact_node+0xdb/0x120
[<0>] kcompactd+0x121/0x2e0
[<0>] kthread+0xcf/0x100
[<0>] ret_from_fork+0x31/0x40
[<0>] ret_from_fork_asm+0x1a/0x30
---}

[akpm@linux-foundation.org: fix build]
Link: https://lkml.kernel.org/r/20250225022002.26141-1-snitzer@kernel.org
Fixes: 96780ca55e ("NFS: fix up nfs_release_folio() to try to release the page")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Cc: Anna Schumaker <anna.schumaker@oracle.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13 13:01:58 +01:00
Trond Myklebust 4fe4ae6c2e NFSv4: Fix a deadlock when recovering state on a sillyrenamed file
[ Upstream commit 8f8df955f0 ]

If the file is sillyrenamed, and slated for delete on close, it is
possible for a server reboot to triggeer an open reclaim, with can again
race with the application call to close(). When that happens, the call
to put_nfs_open_context() can trigger a synchronous delegreturn call
which deadlocks because it is not marked as privileged.

Instead, ensure that the call to nfs4_inode_return_delegation_on_close()
catches the delegreturn, and schedules it asynchronously.

Reported-by: Li Lingfeng <lilingfeng3@huawei.com>
Fixes: adb4b42d19 ("Return the delegation when deleting sillyrenamed files")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-07 18:25:27 +01:00
Trond Myklebust b6423ea93a NFS: Adjust delegated timestamps for O_DIRECT reads and writes
[ Upstream commit 88025c67fe ]

Adjust the timestamps if O_DIRECT is being combined with attribute
delegations.

Fixes: e12912d941 ("NFSv4: Add support for delegated atime and mtime attributes")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-07 18:25:27 +01:00
Trond Myklebust b7b3d772e4 NFS: O_DIRECT writes must check and adjust the file length
[ Upstream commit fcf857ee19 ]

While it is uncommon for delegations to be held while O_DIRECT writes
are in progress, it is possible. The xfstests generic/647 and
generic/729 both end up triggering that state, and end up failing due to
the fact that the file size is not adjusted.

Reported-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219738
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Stable-dep-of: 88025c67fe ("NFS: Adjust delegated timestamps for O_DIRECT reads and writes")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-07 18:25:26 +01:00
Zichen Xie dd8830779b NFS: Fix potential buffer overflowin nfs_sysfs_link_rpc_client()
[ Upstream commit 49fd4e3475 ]

name is char[64] where the size of clnt->cl_program->name remains
unknown. Invoking strcat() directly will also lead to potential buffer
overflow. Change them to strscpy() and strncat() to fix potential
issues.

Signed-off-by: Zichen Xie <zichenxie0106@gmail.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:26 +01:00
Dragan Simic 7cb77019af nfs: Make NFS_FSCACHE select NETFS_SUPPORT instead of depending on it
commit 90190ba1c3 upstream.

Having the NFS_FSCACHE option depend on the NETFS_SUPPORT options makes
selecting NFS_FSCACHE impossible unless another option that additionally
selects NETFS_SUPPORT is already selected.

As a result, for example, being able to reach and select the NFS_FSCACHE
option requires the CEPH_FS or CIFS option to be selected beforehand, which
obviously doesn't make much sense.

Let's correct this by making the NFS_FSCACHE option actually select the
NETFS_SUPPORT option, instead of depending on it.

Fixes: 915cd30cde ("netfs, fscache: Combine fscache with netfs")
Cc: stable@vger.kernel.org
Reported-by: Diederik de Haas <didi.debian@cknow.org>
Signed-off-by: Dragan Simic <dsimic@manjaro.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-17 10:05:39 +01:00
Mike Snitzer 3996a41b1e pnfs/flexfiles: retry getting layout segment for reads
commit eb3fabde15 upstream.

If ff_layout_pg_get_read()'s attempt to get a layout segment results
in -EAGAIN have ff_layout_pg_init_read() retry it after sleeping.

If "softerr" mount is used, use 'io_maxretrans' to limit the number of
attempts to get a layout segment.

This fixes a long-standing issue of O_DIRECT reads failing with
-EAGAIN (11) when using flexfiles Client Side Mirroring (CSM).

Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-17 10:05:39 +01:00
Olga Kornievskaia 265c3dfe97 NFSv4.2: mark OFFLOAD_CANCEL MOVEABLE
[ Upstream commit 668135b934 ]

OFFLOAD_CANCEL should be marked MOVEABLE for when we need to move
tasks off a non-functional transport.

Fixes: c975c20926 ("NFS send OFFLOAD_CANCEL when COPY killed")
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:57:59 +01:00
Olga Kornievskaia 6de31904eb NFSv4.2: fix COPY_NOTIFY xdr buf size calculation
[ Upstream commit e8380c2d06 ]

We need to include sequence size in the compound.

Fixes: 0491567b51 ("NFS: add COPY_NOTIFY operation")
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:57:59 +01:00
Mike Snitzer f4265cd6dd nfs: fix incorrect error handling in LOCALIO
[ Upstream commit ead11ac50a ]

nfs4_stat_to_errno() expects a NFSv4 error code as an argument and
returns a POSIX errno.

The problem is LOCALIO is passing nfs4_stat_to_errno() the POSIX errno
return values from filp->f_op->read_iter(), filp->f_op->write_iter()
and vfs_fsync_range().

So the POSIX errno that nfs_local_pgio_done() and
nfs_local_commit_done() are passing to nfs4_stat_to_errno() are
failing to match any NFSv4 error code, which results in
nfs4_stat_to_errno() defaulting to returning -EREMOTEIO. This causes
assertions in upper layers due to -EREMOTEIO not being a valid NFSv4
error code.

Fix this by updating nfs_local_pgio_done() and nfs_local_commit_done()
to use the new nfs_localio_errno_to_nfs4_stat() to map a POSIX errno
to an NFSv4 error code.

Care was taken to factor out nfs4_errtbl_common[] to avoid duplicating
the same NFS error to errno table. nfs4_errtbl_common[] is checked
first by both nfs4_stat_to_errno and nfs_localio_errno_to_nfs4_stat
before they check their own more specialized tables (nfs4_errtbl[] and
nfs4_errtbl_localio[] respectively).

While auditing the associated error mapping tables, the (ab)use of -1
for the last table entry was removed in favor of using ARRAY_SIZE to
iterate the nfs_errtbl[] and nfs4_errtbl[]. And 'errno_NFSERR_IO' was
removed because it caused needless obfuscation.

Fixes: 70ba381e1a ("nfs: add LOCALIO support")
Reported-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:57:59 +01:00
David Howells 13a07cc81e nfs: Fix oops in nfs_netfs_init_request() when copying to cache
[ Upstream commit 86ad1a58f6 ]

When netfslib wants to copy some data that has just been read on behalf of
nfs, it creates a new write request and calls nfs_netfs_init_request() to
initialise it, but with a NULL file pointer.  This causes
nfs_file_open_context() to oops - however, we don't actually need the nfs
context as we're only going to write to the cache.

Fix this by just returning if we aren't given a file pointer and emit a
warning if the request was for something other than copy-to-cache.

Further, fix nfs_netfs_free_request() so that it doesn't try to free the
context if the pointer is NULL.

Fixes: ee4cdf7ba8 ("netfs: Speed up buffered reading")
Reported-by: Max Kellermann <max.kellermann@ionos.com>
Closes: https://lore.kernel.org/r/CAKPOu+9DyMbKLhyJb7aMLDTb=Fh0T8Teb9sjuf_pze+XWT1VaQ@mail.gmail.com/
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241213135013.2964079-5-dhowells@redhat.com
cc: Trond Myklebust <trondmy@kernel.org>
cc: Anna Schumaker <anna@kernel.org>
cc: Dave Wysochanski <dwysocha@redhat.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-nfs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-17 13:40:34 +01:00
Trond Myklebust 16846e8e0a NFS/pnfs: Fix a live lock between recalled layouts and layoutget
commit 62e2a47cea upstream.

When the server is recalling a layout, we should ignore the count of
outstanding layoutget calls, since the server is expected to return
either NFS4ERR_RECALLCONFLICT or NFS4ERR_RETURNCONFLICT for as long as
the recall is outstanding.
Currently, we may end up livelocking, causing the layout to eventually
be forcibly revoked.

Fixes: bf0291dd22 ("pNFS: Ensure LAYOUTGET and LAYOUTRETURN are properly serialised")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-27 14:02:17 +01:00
Benjamin Coddington bff8460376 nfs/blocklayout: Limit repeat device registration on failure
[ Upstream commit 614733f944 ]

Every pNFS SCSI IO wants to do LAYOUTGET, then within the layout find the
device which can drive GETDEVINFO, then finally may need to prep the device
with a reservation.  This slow work makes a mess of IO latencies if one of
the later steps is going to fail for awhile.

If we're unable to register a SCSI device, ensure we mark the device as
unavailable so that it will timeout and be re-added via GETDEVINFO.  This
avoids repeated doomed attempts to register a device in the IO path.

Add some clarifying comments as well.

Fixes: d869da91cc ("nfs/blocklayout: Fix premature PR key unregistration")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:09 +01:00
Benjamin Coddington faa4bacfae nfs/blocklayout: Don't attempt unregister for invalid block device
[ Upstream commit 3a4ce14d9a ]

Since commit d869da91cc ("nfs/blocklayout: Fix premature PR key
unregistration") an unmount of a pNFS SCSI layout-enabled NFS may
dereference a NULL block_device in:

  bl_unregister_scsi+0x16/0xe0 [blocklayoutdriver]
  bl_free_device+0x70/0x80 [blocklayoutdriver]
  bl_free_deviceid_node+0x12/0x30 [blocklayoutdriver]
  nfs4_put_deviceid_node+0x60/0xc0 [nfsv4]
  nfs4_deviceid_purge_client+0x132/0x190 [nfsv4]
  unset_pnfs_layoutdriver+0x59/0x60 [nfsv4]
  nfs4_destroy_server+0x36/0x70 [nfsv4]
  nfs_free_server+0x23/0xe0 [nfs]
  deactivate_locked_super+0x30/0xb0
  cleanup_mnt+0xba/0x150
  task_work_run+0x59/0x90
  syscall_exit_to_user_mode+0x217/0x220
  do_syscall_64+0x8e/0x160

This happens because even though we were able to create the
nfs4_deviceid_node, the lookup for the device was unable to attach the
block device to the pnfs_block_dev.

If we never found a block device to register, we can avoid this case with
the PNFS_BDEV_REGISTERED flag.  Move the deref behind the test for the
flag.

Fixes: d869da91cc ("nfs/blocklayout: Fix premature PR key unregistration")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:09 +01:00
Li Lingfeng 56a5d998c9 nfs: ignore SB_RDONLY when mounting nfs
[ Upstream commit 52cb7f8f17 ]

When exporting only one file system with fsid=0 on the server side, the
client alternately uses the ro/rw mount options to perform the mount
operation, and a new vfsmount is generated each time.

It can be reproduced as follows:
[root@localhost ~]# mount /dev/sda /mnt2
[root@localhost ~]# echo "/mnt2 *(rw,no_root_squash,fsid=0)" >/etc/exports
[root@localhost ~]# systemctl restart nfs-server
[root@localhost ~]# mount -t nfs -o ro,vers=4 127.0.0.1:/ /mnt/sdaa
[root@localhost ~]# mount -t nfs -o rw,vers=4 127.0.0.1:/ /mnt/sdaa
[root@localhost ~]# mount -t nfs -o ro,vers=4 127.0.0.1:/ /mnt/sdaa
[root@localhost ~]# mount -t nfs -o rw,vers=4 127.0.0.1:/ /mnt/sdaa
[root@localhost ~]# mount | grep nfs4
127.0.0.1:/ on /mnt/sdaa type nfs4 (ro,relatime,vers=4.2,rsize=1048576,...
127.0.0.1:/ on /mnt/sdaa type nfs4 (rw,relatime,vers=4.2,rsize=1048576,...
127.0.0.1:/ on /mnt/sdaa type nfs4 (ro,relatime,vers=4.2,rsize=1048576,...
127.0.0.1:/ on /mnt/sdaa type nfs4 (rw,relatime,vers=4.2,rsize=1048576,...
[root@localhost ~]#

We expected that after mounting with the ro option, using the rw option to
mount again would return EBUSY, but the actual situation was not the case.

As shown above, when mounting for the first time, a superblock with the ro
flag will be generated, and at the same time, in do_new_mount_fc -->
do_add_mount, it detects that the superblock corresponding to the current
target directory is inconsistent with the currently generated one
(path->mnt->mnt_sb != newmnt->mnt.mnt_sb), and a new vfsmount will be
generated.

When mounting with the rw option for the second time, since no matching
superblock can be found in the fs_supers list, a new superblock with the
rw flag will be generated again. The superblock in use (ro) is different
from the newly generated superblock (rw), and a new vfsmount will be
generated again.

When mounting with the ro option for the third time, the superblock (ro)
is found in fs_supers, the superblock in use (rw) is different from the
found superblock (ro), and a new vfsmount will be generated again.

We can switch between ro/rw through remount, and only one superblock needs
to be generated, thus avoiding the problem of repeated generation of
vfsmount caused by switching superblocks.

Furthermore, This can also resolve the issue described in the link.

Fixes: 275a5d24bf ("NFS: Error when mounting the same filesystem with different options")
Link: https://lore.kernel.org/all/20240604112636.236517-3-lilingfeng@huaweicloud.com/
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:09 +01:00
Trond Myklebust 8f95ffb8f8 Revert "nfs: don't reuse partially completed requests in nfs_lock_and_join_requests"
[ Upstream commit 66f9dac907 ]

This reverts commit b571cfcb9d.

This patch appears to assume that if one request is complete, then the
others will complete too before unlocking. That is not a valid
assumption, since other requests could hit a non-fatal error or a short
write that would cause them not to complete.

Reported-by: Igor Raits <igor@gooddata.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219508
Fixes: b571cfcb9d ("nfs: don't reuse partially completed requests in nfs_lock_and_join_requests")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:05 +01:00
NeilBrown de5dac261e nfs/localio: must clear res.replen in nfs_local_read_done
[ Upstream commit 650703bc4e ]

Otherwise memory corruption can occur due to NFSv3 LOCALIO reads
leaving garbage in res.replen:
- nfs3_read_done() copies that into server->read_hdrsize; from there
  nfs3_proc_read_setup() copies it to args.replen in new requests.
- nfs3_xdr_enc_read3args() passes that to rpc_prepare_reply_pages()
  which includes it in hdrsize for xdr_init_pages, so that rq_rcv_buf
  contains a ridiculous len.
- This is copied to rq_private_buf and xs_read_stream_request()
  eventually passes the kvec to sock_recvmsg() which receives incoming
  data into entirely the wrong place.

This is easily reproduced with NFSv3 LOCALIO that is servicing reads
when it is made to pivot back to using normal RPC.  This switch back
to using normal NFSv3 with RPC can occur for a few reasons but this
issue was exposed with a test that stops and then restarts the NFSv3
server while LOCALIO is performing heavy read IO.

Fixes: 70ba381e1a ("nfs: add LOCALIO support")
Reported-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Co-developed-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:03 +01:00
Trond Myklebust b56ae8e715 NFSv4.0: Fix a use-after-free problem in the asynchronous open()
[ Upstream commit 2fdb05dc09 ]

Yang Erkun reports that when two threads are opening files at the same
time, and are forced to abort before a reply is seen, then the call to
nfs_release_seqid() in nfs4_opendata_free() can result in a
use-after-free of the pointer to the defunct rpc task of the other
thread.
The fix is to ensure that if the RPC call is aborted before the call to
nfs_wait_on_sequence() is complete, then we must call nfs_release_seqid()
in nfs4_open_release() before the rpc_task is freed.

Reported-by: Yang Erkun <yangerkun@huawei.com>
Fixes: 24ac23ab88 ("NFSv4: Convert open() into an asynchronous RPC call")
Reviewed-by: Yang Erkun <yangerkun@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:03 +01:00
Mike Snitzer 867da60d46 nfs: avoid i_lock contention in nfs_clear_invalid_mapping
Multi-threaded buffered reads to the same file exposed significant
inode spinlock contention in nfs_clear_invalid_mapping().

Eliminate this spinlock contention by checking flags without locking,
instead using smp_rmb and smp_load_acquire accordingly, but then take
spinlock and double-check these inode flags.

Also refactor nfs_set_cache_invalid() slightly to use
smp_store_release() to pair with nfs_clear_invalid_mapping()'s
smp_load_acquire().

While this fix is beneficial for all multi-threaded buffered reads
issued by an NFS client, this issue was identified in the context of
surprisingly low LOCALIO performance with 4K multi-threaded buffered
read IO.  This fix dramatically speeds up LOCALIO performance:

before: read: IOPS=1583k, BW=6182MiB/s (6482MB/s)(121GiB/20002msec)
after:  read: IOPS=3046k, BW=11.6GiB/s (12.5GB/s)(232GiB/20001msec)

Fixes: 17dfeb9113 ("NFS: Fix races in nfs_revalidate_mapping")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-11-04 10:24:19 -05:00
Mike Snitzer bc29408695 nfs_common: fix localio to cope with racing nfs_local_probe()
Fix the possibility of racing nfs_local_probe() resulting in:
  list_add double add: new=ffff8b99707f9f58, prev=ffff8b99707f9f58, next=ffffffffc0f30000.
  ------------[ cut here ]------------
  kernel BUG at lib/list_debug.c:35!

Add nfs_uuid_init() to properly initialize all nfs_uuid_t members
(particularly its list_head).

Switch to returning bool from nfs_uuid_begin(), returns false if
nfs_uuid_t is already in-use (its list_head is on a list). Update
nfs_local_probe() to return early if the nfs_client's cl_uuid
(nfs_uuid_t) is in-use.

Also, switch nfs_uuid_begin() from using list_add_tail_rcu() to
list_add_tail() -- rculist was used in an earlier version of the
localio code that had a lockless nfs_uuid_lookup interface.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-11-04 10:24:19 -05:00
Trond Myklebust 40f45ab381 NFS: Further fixes to attribute delegation a/mtime changes
When asked to set both an atime and an mtime to the current system time,
ensure that the setting is atomic by calling inode_update_timestamps()
only once with the appropriate flags.

Fixes: e12912d941 ("NFSv4: Add support for delegated atime and mtime attributes")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-11-04 10:24:19 -05:00
Trond Myklebust d054c5eb28 NFS: Fix attribute delegation behaviour on exclusive create
When the client does an exclusive create and the server decides to store
the verifier in the timestamps, a SETATTR is subsequently sent to fix up
those timestamps. When that is the case, suppress the exceptions for
attribute delegations in nfs4_bitmap_copy_adjust().

Fixes: 32215c1f89 ("NFSv4: Don't request atime/mtime/size if they are delegated to us")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-11-04 10:24:19 -05:00
Roberto Sassu dc270d7159 nfs: Fix KMSAN warning in decode_getfattr_attrs()
Fix the following KMSAN warning:

CPU: 1 UID: 0 PID: 7651 Comm: cp Tainted: G    B
Tainted: [B]=BAD_PAGE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009)
=====================================================
=====================================================
BUG: KMSAN: uninit-value in decode_getfattr_attrs+0x2d6d/0x2f90
 decode_getfattr_attrs+0x2d6d/0x2f90
 decode_getfattr_generic+0x806/0xb00
 nfs4_xdr_dec_getattr+0x1de/0x240
 rpcauth_unwrap_resp_decode+0xab/0x100
 rpcauth_unwrap_resp+0x95/0xc0
 call_decode+0x4ff/0xb50
 __rpc_execute+0x57b/0x19d0
 rpc_execute+0x368/0x5e0
 rpc_run_task+0xcfe/0xee0
 nfs4_proc_getattr+0x5b5/0x990
 __nfs_revalidate_inode+0x477/0xd00
 nfs_access_get_cached+0x1021/0x1cc0
 nfs_do_access+0x9f/0xae0
 nfs_permission+0x1e4/0x8c0
 inode_permission+0x356/0x6c0
 link_path_walk+0x958/0x1330
 path_lookupat+0xce/0x6b0
 filename_lookup+0x23e/0x770
 vfs_statx+0xe7/0x970
 vfs_fstatat+0x1f2/0x2c0
 __se_sys_newfstatat+0x67/0x880
 __x64_sys_newfstatat+0xbd/0x120
 x64_sys_call+0x1826/0x3cf0
 do_syscall_64+0xd0/0x1b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The KMSAN warning is triggered in decode_getfattr_attrs(), when calling
decode_attr_mdsthreshold(). It appears that fattr->mdsthreshold is not
initialized.

Fix the issue by initializing fattr->mdsthreshold to NULL in
nfs_fattr_init().

Cc: stable@vger.kernel.org # v3.5.x
Fixes: 88034c3d88 ("NFSv4.1 mdsthreshold attribute xdr")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-11-04 10:24:18 -05:00