Commit Graph

567 Commits

Author SHA1 Message Date
Max Kellermann
5b602344a4 ceph: avoid fs reclaim while using current->journal_info
handle_reply() stores a `ceph_mds_request` pointer in
`current->journal_info` while filling the inode and dentry cache from
an MDS reply.

An allocation in this section can enter direct reclaim and prune
dentries from another filesystem.  If this dirties an ext4 inode, ext4
starts a JBD2 transaction.  JBD2 interprets the Ceph request in
`current->journal_info` as a journal handle and dereferences the
request's `r_tid` as `h_transaction`, causing a kernel crash, e.g.:

 Unable to handle kernel paging request at virtual address 00000000077b4818
 [...]
 Internal error: Oops: 0000000096000004 [#1]  SMP
 Modules linked in:
 CPU: 6 UID: 0 PID: 2699135 Comm: kworker/6:3 Tainted: G        W           6.18.38-i3 #1113 NONE
 [...]
 Workqueue: ceph-msgr ceph_con_workfn
 pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : jbd2__journal_start+0x2c/0x208
 lr : __ext4_journal_start_sb+0x100/0x178
 [...]
 Call trace:
  jbd2__journal_start+0x2c/0x208 (P)
  __ext4_journal_start_sb+0x100/0x178
  ext4_dirty_inode+0x3c/0x90
  __mark_inode_dirty+0x58/0x400
  iput.part.0+0x2b0/0x370
  iput+0x18/0x30
  dentry_unlink_inode+0xc0/0x158
  __dentry_kill+0x80/0x250
  shrink_dentry_list+0x90/0x130
  prune_dcache_sb+0x60/0x98
  super_cache_scan+0xe8/0x190
  do_shrink_slab+0x174/0x388
  shrink_slab+0xd8/0x4c0
  shrink_node+0x31c/0x908
  do_try_to_free_pages+0xd0/0x508
  try_to_free_pages+0x11c/0x238
  __alloc_frozen_pages_noprof+0x4d0/0xdd0
  __folio_alloc_noprof+0x18/0x70
  __filemap_get_folio+0x248/0x440
  ceph_readdir_prepopulate+0x570/0x9e8
  mds_dispatch+0x1424/0x1ba0
  ceph_con_process_message+0x74/0xa0
  ceph_con_v1_try_read+0x3a0/0x1510
  ceph_con_workfn+0x260/0x460

Enter a scoped NOFS allocation context and leave it after clearing
`journal_info`.  This prevents filesystem reclaim from recursing into
another filesystem while the field contains Ceph-private data.

Cc: stable@vger.kernel.org
Fixes: 315f240880 ("ceph: fix security xattr deadlock")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Reviewed-by: Xiubo Li <xiubo.li@clyso.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-07-23 20:29:42 +02:00
Linus Torvalds
5422e496b3 This adds support for manual client session reset in CephFS, allowing
operators to get out of tricky livelock situations involving caps and
 file locks without evicting the problematic client instance on the MDS
 side or rebooting the client node both of which can be disruptive.
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Merge tag 'ceph-for-7.2-rc1' of https://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "This adds support for manual client session reset in CephFS, allowing
  operators to get out of tricky livelock situations involving caps and
  file locks without evicting the problematic client instance on the MDS
  side or rebooting the client node both of which can be disruptive"

* tag 'ceph-for-7.2-rc1' of https://github.com/ceph/ceph-client:
  ceph: add manual reset debugfs control and tracepoints
  ceph: add client reset state machine and session teardown
  ceph: add diagnostic timeout loop to wait_caps_flush()
  ceph: harden send_mds_reconnect and handle active-MDS peer reset
  ceph: use proper endian conversion for flock_len in reconnect
  ceph: convert inode flags to named bit positions and atomic bitops
  rbd: switch to dynamic root device
2026-06-26 16:15:53 -07:00
Alex Markuze
7e1f9e2cd2 ceph: add manual reset debugfs control and tracepoints
Add the debugfs and trace plumbing used to trigger and observe
manual client reset.

The reset interface exposes a trigger file for operator-initiated
reset and a status file for tracking the most recent run.  The
tracepoints record scheduling, completion, and blocked caller
behavior so reset progress can be diagnosed from the client side.

debugfs layout under /sys/kernel/debug/ceph/<client>/reset/:
  trigger - write to initiate a manual reset
  status  - read to see the most recent reset result

The reset directory is cleaned up via debugfs_remove_recursive()
on the parent, so individual file dentries are not stored.

Tracepoints:
  ceph_client_reset_schedule  - reset queued
  ceph_client_reset_complete  - reset finished (success or failure)
  ceph_client_reset_blocked   - caller blocked waiting for reset
  ceph_client_reset_unblocked - caller unblocked after reset

All tracepoints use a null-safe access for monc.auth->global_id
to guard against early-init or late-teardown edge cases.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-06-22 22:45:05 +02:00
Alex Markuze
b52861897b ceph: add client reset state machine and session teardown
Add the client-side reset state machine, request gating, and manual
session teardown implementation.

Manual reset is an operator-triggered escape hatch for client/MDS
stalemates in which caps, locks, or unsafe metadata state stop making
forward progress.  The reset blocks new metadata work, attempts a
bounded best-effort drain of dirty client state while sessions are
still alive, and finally asks the MDS to close sessions before tearing
local session state down directly.

The reset state machine tracks four phases: IDLE -> QUIESCING ->
DRAINING -> TEARDOWN -> IDLE.  QUIESCING is set synchronously by
schedule_reset() before the workqueue item is dispatched, so that new
metadata requests and file-lock acquisitions are gated immediately --
even before the work function begins running.  All non-IDLE phases
block callers on blocked_wq, preventing races with session teardown.

The drain phase flushes mdlog state, dirty caps, and pending cap
releases for a bounded interval.  State that still cannot make progress
within that interval is discarded during teardown, which is the point
of the reset: break the stalemate and allow fresh sessions to rebuild
clean state.

The session teardown follows the established check_new_map()
forced-close pattern: unregister sessions under mdsc->mutex, then clean
up caps and requests under s->s_mutex.  Reconnect is not attempted
because the MDS only accepts reconnects during its own RECONNECT phase
after restart, not from an active client.

Blocked callers are released when reset completes and observe the final
result via -EAGAIN (reset failed) or 0 (success).  Internal work-function
errors such as -ENOMEM are not propagated to unrelated callers like
open() or flock(); the detailed error remains in debugfs and
tracepoints.

The work function checks st->shutdown before each phase transition
(DRAINING, TEARDOWN) so that a concurrent ceph_mdsc_destroy() is not
overwritten.  If destroy already took ownership, the work function
releases session references and returns without touching the state.

The timeout calculation for blocked-request waiters uses max_t() to
prevent jiffies underflow when the deadline has already passed.

The close-grace sleep before teardown is a best-effort nudge to let
queued REQUEST_CLOSE messages egress; it is not a correctness
requirement since the MDS still has session_autoclose as a fallback.

The destroy path marks reset as failed and wakes blocked waiters before
cancel_work_sync() so unmount does not stall.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-06-22 22:45:00 +02:00
Alex Markuze
ebbbab66bd ceph: add diagnostic timeout loop to wait_caps_flush()
Convert wait_caps_flush() from a silent indefinite wait into a diagnostic
wait loop that periodically dumps pending cap flush state.

The underlying wait semantics remain intact: callers still wait until the
requested cap flushes complete. The difference is that long stalls now
produce actionable diagnostics instead of looking like a silent hang.

CEPH_CAP_FLUSH_MAX_DUMP_ENTRIES limits the number of entries
emitted per diagnostic dump, and CEPH_CAP_FLUSH_MAX_DUMP_ITERS
limits the number of timed diagnostic dumps before the wait
continues silently.  When more entries exist than the per-dump
limit, a truncation count is reported.  When the dump iteration
limit is reached, a final suppression message is emitted so the
transition to silence is explicit.

The diagnostic dump collects flush entry data under cap_dirty_lock into
a bounded on-stack array, then prints after releasing the lock.  This
avoids holding the spinlock across printk calls.

A null cf->ci on the global flush list indicates a bug since all
cap_flush entries are initialized with a valid ci before being added.
Signal this with WARN_ON_ONCE while still printing enough context for
debugging.

READ_ONCE is used for the i_last_cap_flush_ack field, which is read
outside the inode lock domain. Flush tids are monotonically increasing
and acks are processed in order under i_ceph_lock, so the latest ack
tid is always the most recently written value.

Add a ci pointer to struct ceph_cap_flush so that the diagnostic
dump can identify which inode each pending flush belongs to.  The
new i_last_cap_flush_ack field tracks the latest acknowledged flush
tid per inode for diagnostic correlation.

This improves reset-drain observability and is also useful for
existing sync and writeback troubleshooting paths.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-06-22 22:44:56 +02:00
Alex Markuze
39fe303158 ceph: harden send_mds_reconnect and handle active-MDS peer reset
Change send_mds_reconnect() to return an error code so callers can detect
and report reconnect failures instead of silently ignoring them. Add early
bailout checks for sessions that are already closed, rejected, or
unregistered, which avoids sending reconnect messages for sessions that
can no longer be recovered.

The early -ESTALE and -ENOENT bailouts use a separate fail_return label
that skips the pr_err_client diagnostic, since these codes indicate
expected concurrent-teardown races rather than genuine reconnect build
failures.

Move the "reconnect start" log after the early-bailout checks so it
only appears for sessions that actually proceed with reconnect.

Save the prior session state before transitioning to RECONNECTING,
and restore it in the failure path.  Without this, a transient
build or encoding failure (-ENOMEM, -ENOSPC) strands the session
in RECONNECTING indefinitely because check_new_map() only retries
sessions in RESTARTING state.

Rewrite mds_peer_reset() to handle the case where the MDS is past its
RECONNECT phase (i.e. active). An active MDS rejects CLIENT_RECONNECT
messages because it only accepts them during its own RECONNECT window
after restart. Previously, the client would send a doomed reconnect
that the MDS would reject or ignore. Now, the client tears the session
down locally and lets new requests re-open a fresh session, which is
the correct recovery for this scenario. The RECONNECTING state is
handled on the same teardown path, since the MDS will reject reconnect
attempts from an active client regardless of the session's local state.

Add explicit cases for CLOSED and REJECTED session states in
mds_peer_reset() since these are terminal states where a connection
drop is expected behavior.

The session teardown path in mds_peer_reset() follows the established
drop-and-reacquire locking pattern from check_new_map(): take
mdsc->mutex for session unregistration, release it, then take s->s_mutex
separately for cleanup. This avoids introducing a new simultaneous lock
nesting pattern.

Log reconnect failures from check_new_map() and mds_peer_reset() at
pr_warn level rather than pr_err, since return codes like -ESTALE
(closed/rejected session) and -ENOENT (unregistered session) are
expected during concurrent teardown. Log dropped messages for
unregistered sessions via doutc() (dynamic debug) rather than
pr_info, as post-reset message arrival is routine and does not
warrant unconditional logging.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-06-22 22:44:50 +02:00
Alex Markuze
248e514000 ceph: use proper endian conversion for flock_len in reconnect
Replace the __force __le32 cast with cpu_to_le32() for the flock_len field
in reconnect_caps_cb(). The old code used a type-system bypass to silence
sparse; the new form uses the proper endian conversion macro.

Also switch from a raw bitmask test against i_ceph_flags to test_bit() on
the named CEPH_I_ERROR_FILELOCK_BIT, which is the correct accessor for the
unsigned long flags field after the bit-position conversion.

Remove the now-unused CEPH_I_ERROR_FILELOCK mask define since all callers
use the _BIT form with test_bit/set_bit/clear_bit.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-06-22 22:44:47 +02:00
Alex Markuze
e120e2b666 ceph: convert inode flags to named bit positions and atomic bitops
Define named bit-position constants for all CEPH_I_* inode flags and
derive the bitmask values from them.  This gives every flag a named
_BIT constant usable with the test_bit/set_bit/clear_bit family.
The intentionally unused bit position 1 is documented inline.

Convert all flag modifications to use atomic bitops (set_bit,
clear_bit, test_and_clear_bit).  The previous code mixed lockless
atomic ops on some flags (ERROR_WRITE, ODIRECT) with non-atomic
read-modify-write (|= / &= ~) on other flags sharing the same
unsigned long.  A concurrent non-atomic RMW can clobber an
adjacent lockless atomic update -- for example, a lockless
clear_bit(ERROR_WRITE) could be silently resurrected by a
concurrent ci->i_ceph_flags |= CEPH_I_FLUSH under the spinlock.
Using atomic bitops for all modifications eliminates this class
of race entirely.

Flags whose only users are now the _BIT form (ERROR_WRITE,
ASYNC_CHECK_CAPS) have their old mask defines removed to document
that callers must use the _BIT constant with the set_bit/test_bit
family.  ERROR_FILELOCK and SHUTDOWN retain their mask defines
because they are still used via bitmask tests in lockless readers
(ceph_inode_is_shutdown, reconnect_caps_cb).

The direct assignment in ceph_finish_async_create() is converted
from i_ceph_flags = CEPH_I_ASYNC_CREATE to set_bit().  This
inode is I_NEW at this point -- still invisible to other threads
and guaranteed to have zero flags from alloc_inode -- so either
form is safe, but set_bit() keeps the conversion uniform.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-06-22 22:44:42 +02:00
Mateusz Guzik
769e143b11
fs: add icount_read_once() and stop open-coding ->i_count loads
Similarly to inode_state_read_once(), it makes the caller spell out
they acknowledge instability of the returned value.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20260421182538.1215894-2-mjguzik@gmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-05-11 23:12:28 +02:00
Linus Torvalds
ac2dc6d574 We have a series from Alex which extends CephFS client metrics with
support for per-subvolume data I/O performance and latency tracking
 (metadata operations aren't included) and a good variety of fixes and
 cleanups across RBD and CephFS.
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Merge tag 'ceph-for-7.1-rc1' of https://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "We have a series from Alex which extends CephFS client metrics with
  support for per-subvolume data I/O performance and latency tracking
  (metadata operations aren't included) and a good variety of fixes and
  cleanups across RBD and CephFS"

* tag 'ceph-for-7.1-rc1' of https://github.com/ceph/ceph-client:
  ceph: add subvolume metrics collection and reporting
  ceph: parse subvolume_id from InodeStat v9 and store in inode
  ceph: handle InodeStat v8 versioned field in reply parsing
  libceph: Fix slab-out-of-bounds access in auth message processing
  rbd: fix null-ptr-deref when device_add_disk() fails
  crush: cleanup in crush_do_rule() method
  ceph: clear s_cap_reconnect when ceph_pagelist_encode_32() fails
  ceph: only d_add() negative dentries when they are unhashed
  libceph: update outdated comment in ceph_sock_write_space()
  libceph: Remove obsolete session key alignment logic
  ceph: fix num_ops off-by-one when crypto allocation fails
  libceph: Prevent potential null-ptr-deref in ceph_handle_auth_reply()
2026-04-24 13:47:19 -07:00
Alex Markuze
b1137e0b3d ceph: add subvolume metrics collection and reporting
Add complete infrastructure for per-subvolume I/O metrics collection
and reporting to the MDS. This enables administrators to monitor I/O
patterns at the subvolume granularity, which is useful for multi-tenant
CephFS deployments.

This patch adds:
- CEPHFS_FEATURE_SUBVOLUME_METRICS feature flag for MDS negotiation
- CEPH_SUBVOLUME_ID_NONE constant (0) for unknown/unset state
- Red-black tree based metrics tracker for efficient per-subvolume
  aggregation with kmem_cache for entry allocations
- Wire format encoding matching the MDS C++ AggregatedIOMetrics struct
- Integration with the existing CLIENT_METRICS message
- Recording of I/O operations from file read/write and writeback paths
- Debugfs interfaces for monitoring (metrics/subvolumes, metrics/metric_features)

Metrics tracked per subvolume include:
- Read/write operation counts
- Read/write byte counts
- Read/write latency sums (for average calculation)

The metrics are periodically sent to the MDS as part of the existing
metrics reporting infrastructure when the MDS advertises support for
the SUBVOLUME_METRICS feature.

CEPH_SUBVOLUME_ID_NONE enforces subvolume_id immutability. Following
the FUSE client convention, 0 means unknown/unset. Once an inode has
a valid (non-zero) subvolume_id, it should not change during the
inode's lifetime.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:23 +02:00
Alex Markuze
4a1c543479 ceph: parse subvolume_id from InodeStat v9 and store in inode
Add support for parsing the subvolume_id field from InodeStat v9 and
storing it in the inode for later use by subvolume metrics tracking.

The subvolume_id identifies which CephFS subvolume an inode belongs to,
enabling per-subvolume I/O metrics collection and reporting.

This patch:
- Adds subvolume_id field to struct ceph_mds_reply_info_in
- Adds i_subvolume_id field to struct ceph_inode_info
- Parses subvolume_id from v9 InodeStat in parse_reply_info_in()
- Adds ceph_inode_set_subvolume() helper to propagate the ID to inodes
- Initializes i_subvolume_id in inode allocation and clears on destroy

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:23 +02:00
Alex Markuze
e58103caff ceph: handle InodeStat v8 versioned field in reply parsing
Add forward-compatible handling for the new versioned field introduced
in InodeStat v8. This patch only skips the field without using it,
preparing for future protocol extensions.

The v8 encoding adds a versioned sub-structure that needs to be properly
decoded and skipped to maintain compatibility with newer MDS versions.

Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:23 +02:00
Max Kellermann
cc56430954 ceph: clear s_cap_reconnect when ceph_pagelist_encode_32() fails
This MDS reconnect error path leaves s_cap_reconnect set.
send_mds_reconnect() sets the bit at the beginning of the reconnect,
but the first failing operation after that, ceph_pagelist_encode_32(),
can jump to `fail:` without clearing it.

__ceph_remove_cap() consults that flag to decide whether cap releases
should be queued. A reconnect-preparation failure therefore leaves the
session in reconnect mode from the cap-release path's point of view
and can strand release work until some later state transition repairs
it.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-04-22 01:40:23 +02:00
Al Viro
2420067cec struct dentry: make ->d_u anonymous
Making ->d_rcu and (then) ->d_child overlapping dates back to
2006; anon unions support had been added to gcc only in 4.6
(2011) and the minimal gcc version hadn't been bumped to that
until 4.19 (2018).

These days there's no reason not to keep that union named.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2026-04-02 03:47:31 -04:00
Al Viro
408d8af01f for_each_alias(): helper macro for iterating through dentries of given inode
Most of the places using d_alias are loops iterating through all aliases for
given inode; introduce a helper macro (for_each_alias(dentry, inode))
and convert open-coded instances of such loop to it.

They are easier to read that way and it reduces the noise on the next steps.

You _must_ hold inode->i_lock over that thing.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2026-04-02 03:45:02 -04:00
Max Kellermann
040d159a45 ceph: fix memory leaks in ceph_mdsc_build_path()
Add __putname() calls to error code paths that did not free the "path"
pointer obtained by __getname().  If ownership of this pointer is not
passed to the caller via path_info.path, the function must free it
before returning.

Cc: stable@vger.kernel.org
Fixes: 3fd945a79e ("ceph: encode encrypted name in ceph_mdsc_build_path and dentry release")
Fixes: 550f7ca98e ("ceph: give up on paths longer than PATH_MAX")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-03-09 12:34:40 +01:00
Kees Cook
189f164e57 Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses
Conversion performed via this Coccinelle script:

  // SPDX-License-Identifier: GPL-2.0-only
  // Options: --include-headers-for-types --all-includes --include-headers --keep-comments
  virtual patch

  @gfp depends on patch && !(file in "tools") && !(file in "samples")@
  identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex,
 		    kzalloc_obj,kzalloc_objs,kzalloc_flex,
		    kvmalloc_obj,kvmalloc_objs,kvmalloc_flex,
		    kvzalloc_obj,kvzalloc_objs,kvzalloc_flex};
  @@

  	ALLOC(...
  -		, GFP_KERNEL
  	)

  $ make coccicheck MODE=patch COCCI=gfp.cocci

Build and boot tested x86_64 with Fedora 42's GCC and Clang:

Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01

Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-22 08:26:33 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Viacheslav Dubeyko
7987cce375 ceph: fix NULL pointer dereference in ceph_mds_auth_match()
The CephFS kernel client has regression starting from 6.18-rc1.
We have issue in ceph_mds_auth_match() if fs_name == NULL:

    const char fs_name = mdsc->fsc->mount_options->mds_namespace;
    ...
    if (auth->match.fs_name && strcmp(auth->match.fs_name, fs_name)) {
            / fsname mismatch, try next one */
            return 0;
    }

Patrick Donnelly suggested that: In summary, we should definitely start
decoding `fs_name` from the MDSMap and do strict authorizations checks
against it. Note that the `-o mds_namespace=foo` should only be used for
selecting the file system to mount and nothing else. It's possible
no mds_namespace is specified but the kernel will mount the only
file system that exists which may have name "foo".

This patch reworks ceph_mdsmap_decode() and namespace_equals() with
the goal of supporting the suggested concept. Now struct ceph_mdsmap
contains m_fs_name field that receives copy of extracted FS name
by ceph_extract_encoded_string(). For the case of "old" CephFS file
systems, it is used "cephfs" name.

[ idryomov: replace redundant %*pE with %s in ceph_mdsmap_decode(),
  get rid of a series of strlen() calls in ceph_namespace_match(),
  drop changes to namespace_equals() body to avoid treating empty
  mds_namespace as equal, drop changes to ceph_mdsc_handle_fsmap()
  as namespace_equals() isn't an equivalent substitution there ]

Cc: stable@vger.kernel.org
Fixes: 22c73d52a6 ("ceph: fix multifs mds auth caps issue")
Link: https://tracker.ceph.com/issues/73886
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Patrick Donnelly <pdonnell@ibm.com>
Tested-by: Patrick Donnelly <pdonnell@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2026-02-04 22:00:42 +01:00
Max Kellermann
d927a595ab ceph: add trace points to the MDS client
This patch adds trace points to the Ceph filesystem MDS client:

- request submission (CEPH_MSG_CLIENT_REQUEST) and completion
  (CEPH_MSG_CLIENT_REPLY)
- capabilities (CEPH_MSG_CLIENT_CAPS)

These are the central pieces that are useful for analyzing MDS
latency/performance problems from the client's perspective.

In the long run, all doutc() calls should be replaced with
tracepoints.  This way, the Ceph filesystem can be traced at any time
(without spamming the kernel log).  Additionally, trace points can be
used in BPF programs (which can even deference the pointer parameters
and extract more values).

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-12-10 11:50:54 +01:00
Linus Torvalds
8bd9238e51 Some messenger improvements from Eric and Max, a patch to address the
issue (also affected userspace) of incorrect permissions being granted
 to users who have access to multiple different CephFS instances within
 the same cluster from Kotresh and a bunch of assorted CephFS fixes from
 Slava.
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Merge tag 'ceph-for-6.18-rc1' of https://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:

 - some messenger improvements (Eric and Max)

 - address an issue (also affected userspace) of incorrect permissions
   being granted to users who have access to multiple different CephFS
   instances within the same cluster (Kotresh)

 - a bunch of assorted CephFS fixes (Slava)

* tag 'ceph-for-6.18-rc1' of https://github.com/ceph/ceph-client:
  ceph: add bug tracking system info to MAINTAINERS
  ceph: fix multifs mds auth caps issue
  ceph: cleanup in ceph_alloc_readdir_reply_buffer()
  ceph: fix potential NULL dereference issue in ceph_fill_trace()
  libceph: add empty check to ceph_con_get_out_msg()
  libceph: pass the message pointer instead of loading con->out_msg
  libceph: make ceph_con_get_out_msg() return the message pointer
  ceph: fix potential race condition on operations with CEPH_I_ODIRECT flag
  ceph: refactor wake_up_bit() pattern of calling
  ceph: fix potential race condition in ceph_ioctl_lazyio()
  ceph: fix overflowed constant issue in ceph_do_objects_copy()
  ceph: fix wrong sizeof argument issue in register_session()
  ceph: add checking of wait_for_completion_killable() return value
  ceph: make ceph_start_io_*() killable
  libceph: Use HMAC-SHA256 library instead of crypto_shash
2025-10-10 11:30:19 -07:00
Kotresh HR
22c73d52a6 ceph: fix multifs mds auth caps issue
The mds auth caps check should also validate the
fsname along with the associated caps. Not doing
so would result in applying the mds auth caps of
one fs on to the other fs in a multifs ceph cluster.
The bug causes multiple issues w.r.t user
authentication, following is one such example.

Steps to Reproduce (on vstart cluster):
1. Create two file systems in a cluster, say 'fsname1' and 'fsname2'
2. Authorize read only permission to the user 'client.usr' on fs 'fsname1'
    $ceph fs authorize fsname1 client.usr / r
3. Authorize read and write permission to the same user 'client.usr' on fs 'fsname2'
    $ceph fs authorize fsname2 client.usr / rw
4. Update the keyring
    $ceph auth get client.usr >> ./keyring

With above permssions for the user 'client.usr', following is the
expectation.
  a. The 'client.usr' should be able to only read the contents
     and not allowed to create or delete files on file system 'fsname1'.
  b. The 'client.usr' should be able to read/write on file system 'fsname2'.

But, with this bug, the 'client.usr' is allowed to read/write on file
system 'fsname1'. See below.

5. Mount the file system 'fsname1' with the user 'client.usr'
     $sudo bin/mount.ceph usr@.fsname1=/ /kmnt_fsname1_usr/
6. Try creating a file on file system 'fsname1' with user 'client.usr'. This
   should fail but passes with this bug.
     $touch /kmnt_fsname1_usr/file1
7. Mount the file system 'fsname1' with the user 'client.admin' and create a
   file.
     $sudo bin/mount.ceph admin@.fsname1=/ /kmnt_fsname1_admin
     $echo "data" > /kmnt_fsname1_admin/admin_file1
8. Try removing an existing file on file system 'fsname1' with the user
   'client.usr'. This shoudn't succeed but succeeds with the bug.
     $rm -f /kmnt_fsname1_usr/admin_file1

For more information, please take a look at the corresponding mds/fuse patch
and tests added by looking into the tracker mentioned below.

v2: Fix a possible null dereference in doutc
v3: Don't store fsname from mdsmap, validate against
    ceph_mount_options's fsname and use it
v4: Code refactor, better warning message and
    fix possible compiler warning

[ Slava.Dubeyko: "fsname check failed" -> "fsname mismatch" ]

Link: https://tracker.ceph.com/issues/72167
Signed-off-by: Kotresh HR <khiremat@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-10-08 23:30:47 +02:00
Viacheslav Dubeyko
c66120c842 ceph: cleanup in ceph_alloc_readdir_reply_buffer()
The Coverity Scan service has reported potential issue
in ceph_alloc_readdir_reply_buffer() [1]. If order could
be negative one, then it expects the issue in the logic:

num_entries = (PAGE_SIZE << order) / size;

Technically speaking, this logic [2] should prevent from
making the order variable negative:

if (!rinfo->dir_entries)
    return -ENOMEM;

However, the allocation logic requires some cleanup.
This patch makes sure that calculated bytes count
will never exceed ULONG_MAX before get_order()
calculation. And it adds the checking of order
variable on negative value to guarantee that second
half of the function's code will never operate by
negative value of order variable even if something
will be wrong or to be changed in the first half of
the function's logic.

v2
Alex Markuze suggested to add unlikely() macro
for introduced condition checks.

[1] https://scan5.scan.coverity.com/#/project-view/64304/10063?selectedIssue=1198252
[2] https://elixir.bootlin.com/linux/v6.17-rc3/source/fs/ceph/mds_client.c#L2553

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-10-08 23:30:47 +02:00
Viacheslav Dubeyko
1ed4471a4e ceph: fix wrong sizeof argument issue in register_session()
The Coverity Scan service has detected the wrong sizeof
argument in register_session() [1]. The CID 1598909 defect
contains explanation: "The wrong sizeof value is used in
an expression or as argument to a function. The result is
an incorrect value that may cause unexpected program behaviors.
In register_session: The sizeof operator is invoked on
the wrong argument (CWE-569)".

The patch introduces a ptr_size variable that is initialized
by sizeof(struct ceph_mds_session *). And this variable is used
instead of sizeof(void *) in the code.

[1] https://scan5.scan.coverity.com/#/project-view/64304/10063?selectedIssue=1598909

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-10-08 23:30:46 +02:00
Linus Torvalds
56e7b31071 vfs-6.18-rc1.inode
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Merge tag 'vfs-6.18-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs inode updates from Christian Brauner:
 "This contains a series I originally wrote and that Eric brought over
  the finish line. It moves out the i_crypt_info and i_verity_info
  pointers out of 'struct inode' and into the fs-specific part of the
  inode.

  So now the few filesytems that actually make use of this pay the price
  in their own private inode storage instead of forcing it upon every
  user of struct inode.

  The pointer for the crypt and verity info is simply found by storing
  an offset to its address in struct fsverity_operations and struct
  fscrypt_operations. This shrinks struct inode by 16 bytes.

  I hope to move a lot more out of it in the future so that struct inode
  becomes really just about very core stuff that we need, much like
  struct dentry and struct file, instead of the dumping ground it has
  become over the years.

  On top of this are a various changes associated with the ongoing inode
  lifetime handling rework that multiple people are pushing forward:

   - Stop accessing inode->i_count directly in f2fs and gfs2. They
     simply should use the __iget() and iput() helpers

   - Make the i_state flags an enum

   - Rework the iput() logic

     Currently, if we are the last iput, and we have the I_DIRTY_TIME
     bit set, we will grab a reference on the inode again and then mark
     it dirty and then redo the put. This is to make sure we delay the
     time update for as long as possible

     We can rework this logic to simply dec i_count if it is not 1, and
     if it is do the time update while still holding the i_count
     reference

     Then we can replace the atomic_dec_and_lock with locking the
     ->i_lock and doing atomic_dec_and_test, since we did the
     atomic_add_unless above

   - Add an icount_read() helper and convert everyone that accesses
     inode->i_count directly for this purpose to use the helper

   - Expand dump_inode() to dump more information about an inode helping
     in debugging

   - Add some might_sleep() annotations to iput() and associated
     helpers"

* tag 'vfs-6.18-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fs: add might_sleep() annotation to iput() and more
  fs: expand dump_inode()
  inode: fix whitespace issues
  fs: add an icount_read helper
  fs: rework iput logic
  fs: make the i_state flags an enum
  fs: stop accessing ->i_count directly in f2fs and gfs2
  fsverity: check IS_VERITY() in fsverity_cleanup_inode()
  fs: remove inode::i_verity_info
  btrfs: move verity info pointer to fs-specific part of inode
  f2fs: move verity info pointer to fs-specific part of inode
  ext4: move verity info pointer to fs-specific part of inode
  fsverity: add support for info in fs-specific part of inode
  fs: remove inode::i_crypt_info
  ceph: move crypt info pointer to fs-specific part of inode
  ubifs: move crypt info pointer to fs-specific part of inode
  f2fs: move crypt info pointer to fs-specific part of inode
  ext4: move crypt info pointer to fs-specific part of inode
  fscrypt: add support for info in fs-specific part of inode
  fscrypt: replace raw loads of info pointer with helper function
2025-09-29 09:42:30 -07:00
Alex Markuze
15f519e9f8 ceph: fix race condition validating r_parent before applying state
Add validation to ensure the cached parent directory inode matches the
directory info in MDS replies. This prevents client-side race conditions
where concurrent operations (e.g. rename) cause r_parent to become stale
between request initiation and reply processing, which could lead to
applying state changes to incorrect directory inodes.

[ idryomov: folded a kerneldoc fixup and a follow-up fix from Alex to
  move CEPH_CAP_PIN reference when r_parent is updated:

  When the parent directory lock is not held, req->r_parent can become
  stale and is updated to point to the correct inode.  However, the
  associated CEPH_CAP_PIN reference was not being adjusted.  The
  CEPH_CAP_PIN is a reference on an inode that is tracked for
  accounting purposes.  Moving this pin is important to keep the
  accounting balanced. When the pin was not moved from the old parent
  to the new one, it created two problems: The reference on the old,
  stale parent was never released, causing a reference leak.
  A reference for the new parent was never acquired, creating the risk
  of a reference underflow later in ceph_mdsc_release_request().  This
  patch corrects the logic by releasing the pin from the old parent and
  acquiring it for the new parent when r_parent is switched.  This
  ensures reference accounting stays balanced. ]

Cc: stable@vger.kernel.org
Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-09-09 12:57:02 +02:00
Josef Bacik
37b27bd5d6
fs: add an icount_read helper
Instead of doing direct access to ->i_count, add a helper to handle
this. This will make it easier to convert i_count to a refcount later.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/9bc62a84c6b9d6337781203f60837bd98fbc4a96.1756222464.git.josef@toxicpanda.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-01 12:41:09 +02:00
Al Viro
0d2da2561b ceph: fix a race with rename() in ceph_mdsc_build_path()
Lift copying the name into callers of ceph_encode_encrypted_dname()
that do not have it already copied; ceph_encode_encrypted_fname()
disappears.

That fixes a UAF in ceph_mdsc_build_path() - while the initial copy
of plaintext into buf is done under ->d_lock, we access the
original name again in ceph_encode_encrypted_fname() and that is
done without any locking.  With ceph_encode_encrypted_dname() using
the stable copy the problem goes away.

Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-06-17 17:58:14 -04:00
Viacheslav Dubeyko
fd7449d937
ceph: fix generic/421 test failure
The generic/421 fails to finish because of the issue:

Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.894678] INFO: task kworker/u48:0:11 blocked for more than 122 seconds.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895403] Not tainted 6.13.0-rc5+ #1
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895867] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896633] task:kworker/u48:0 state:D stack:0 pid:11 tgid:11 ppid:2 flags:0x00004000
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896641] Workqueue: writeback wb_workfn (flush-ceph-24)
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897614] Call Trace:
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897620] <TASK>
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897629] __schedule+0x443/0x16b0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897637] schedule+0x2b/0x140
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897640] io_schedule+0x4c/0x80
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897643] folio_wait_bit_common+0x11b/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897646] ? _raw_spin_unlock_irq+0xe/0x50
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897652] ? __pfx_wake_page_function+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897655] __folio_lock+0x17/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897658] ceph_writepages_start+0xca9/0x1fb0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897663] ? fsnotify_remove_queued_event+0x2f/0x40
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897668] do_writepages+0xd2/0x240
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897672] __writeback_single_inode+0x44/0x350
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897675] writeback_sb_inodes+0x25c/0x550
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897680] wb_writeback+0x89/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897683] ? finish_task_switch.isra.0+0x97/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897687] wb_workfn+0xb5/0x410
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897689] process_one_work+0x188/0x3d0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897692] worker_thread+0x2b5/0x3c0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897694] ? __pfx_worker_thread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897696] kthread+0xe1/0x120
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897699] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897701] ret_from_fork+0x43/0x70
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897705] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897707] ret_from_fork_asm+0x1a/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897711] </TASK>

There are several issues here:
(1) ceph_kill_sb() doesn't wait ending of flushing
all dirty folios/pages because of racy nature of
mdsc->stopping_blockers. As a result, mdsc->stopping
becomes CEPH_MDSC_STOPPING_FLUSHED too early.
(2) The ceph_inc_osd_stopping_blocker(fsc->mdsc) fails
to increment mdsc->stopping_blockers. Finally,
already locked folios/pages are never been unlocked
and the logic tries to lock the same page second time.
(3) The folio_batch with found dirty pages by
filemap_get_folios_tag() is not processed properly.
And this is why some number of dirty pages simply never
processed and we have dirty folios/pages after unmount
anyway.

This patch fixes the issues by means of:
(1) introducing dirty_folios counter and flush_end_wq
waiting queue in struct ceph_mds_client;
(2) ceph_dirty_folio() increments the dirty_folios
counter;
(3) writepages_finish() decrements the dirty_folios
counter and wake up all waiters on the queue
if dirty_folios counter is equal or lesser than zero;
(4) adding in ceph_kill_sb() method the logic of
checking the value of dirty_folios counter and
waiting if it is bigger than zero;
(5) adding ceph_inc_osd_stopping_blocker() call in the
beginning of the ceph_writepages_start() and
ceph_dec_osd_stopping_blocker() at the end of
the ceph_writepages_start() with the goal to resolve
the racy nature of mdsc->stopping_blockers.

sudo ./check generic/421
FSTYP         -- ceph
PLATFORM      -- Linux/x86_64 ceph-testing-0001 6.13.0+ #137 SMP PREEMPT_DYNAMIC Mon Feb  3 20:30:08 UTC 2025
MKFS_OPTIONS  -- 127.0.0.1:40551:/scratch
MOUNT_OPTIONS -- -o name=fs,secret=<secret>,ms_mode=crc,nowsync,copyfrom 127.0.0.1:40551:/scratch /mnt/scratch

generic/421 7s ...  4s
Ran: generic/421
Passed all 1 tests

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Link: https://lore.kernel.org/r/20250205000249.123054-5-slava@dubeyko.com
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:20:16 +01:00
Linus Torvalds
626d1a1e99 A fix for a memory leak from Antoine (marked for stable) and two
cleanups from Liang and Slava, all in CephFS.
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Merge tag 'ceph-for-6.14-rc1' of https://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "A fix for a memory leak from Antoine (marked for stable) and two
  cleanups from Liang and Slava"

* tag 'ceph-for-6.14-rc1' of https://github.com/ceph/ceph-client:
  ceph: exchange hardcoded value on NAME_MAX
  ceph: streamline request head structures in MDS client
  ceph: fix memory leak in ceph_mds_auth_match()
2025-01-31 10:30:34 -08:00
Linus Torvalds
d3d90cc289 Provide stable parent and name to ->d_revalidate() instances
Most of the filesystem methods where we care about dentry name
 and parent have their stability guaranteed by the callers;
 ->d_revalidate() is the major exception.
 
 It's easy enough for callers to supply stable values for
 expected name and expected parent of the dentry being
 validated.  That kills quite a bit of boilerplate in
 ->d_revalidate() instances, along with a bunch of races
 where they used to access ->d_name without sufficient
 precautions.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-revalidate' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs d_revalidate updates from Al Viro:
 "Provide stable parent and name to ->d_revalidate() instances

  Most of the filesystem methods where we care about dentry name and
  parent have their stability guaranteed by the callers;
  ->d_revalidate() is the major exception.

  It's easy enough for callers to supply stable values for expected name
  and expected parent of the dentry being validated. That kills quite a
  bit of boilerplate in ->d_revalidate() instances, along with a bunch
  of races where they used to access ->d_name without sufficient
  precautions"

* tag 'pull-revalidate' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  9p: fix ->rename_sem exclusion
  orangefs_d_revalidate(): use stable parent inode and name passed by caller
  ocfs2_dentry_revalidate(): use stable parent inode and name passed by caller
  nfs: fix ->d_revalidate() UAF on ->d_name accesses
  nfs{,4}_lookup_validate(): use stable parent inode passed by caller
  gfs2_drevalidate(): use stable parent inode and name passed by caller
  fuse_dentry_revalidate(): use stable parent inode and name passed by caller
  vfat_revalidate{,_ci}(): use stable parent inode passed by caller
  exfat_d_revalidate(): use stable parent inode passed by caller
  fscrypt_d_revalidate(): use stable parent inode passed by caller
  ceph_d_revalidate(): propagate stable name down into request encoding
  ceph_d_revalidate(): use stable parent inode passed by caller
  afs_d_revalidate(): use stable name and parent inode passed by caller
  Pass parent directory inode and expected name to ->d_revalidate()
  generic_ci_d_compare(): use shortname_storage
  ext4 fast_commit: make use of name_snapshot primitives
  dissolve external_name.u into separate members
  make take_dentry_name_snapshot() lockless
  dcache: back inline names with a struct-wrapped array of unsigned long
  make sure that DNAME_INLINE_LEN is a multiple of word size
2025-01-30 09:13:35 -08:00
Al Viro
541795cb0b ceph_d_revalidate(): propagate stable name down into request encoding
Currently get_fscrypt_altname() requires ->r_dentry->d_name to be stable
and it gets that in almost all cases.  The only exception is ->d_revalidate(),
where we have a stable name, but it's passed separately - dentry->d_name
is not stable there.

Propagate it down to get_fscrypt_altname() as a new field of struct
ceph_mds_request - ->r_dname, to be used instead ->r_dentry->d_name
when non-NULL.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-01-27 19:25:23 -05:00
Liang Jie
2f0805d7c0 ceph: streamline request head structures in MDS client
The existence of the ceph_mds_request_head_old structure in the MDS
client code is no longer required due to improvements in handling
different MDS request header versions. This patch removes the now
redundant ceph_mds_request_head_old structure and replaces its usage
with the flexible and extensible ceph_mds_request_head structure.

Changes include:
- Modification of find_legacy_request_head to directly cast the
  pointer to ceph_mds_request_head_legacy without going through the
  old structure.
- Update sizeof calculations in create_request_message to use
  offsetofend for consistency and future-proofing, rather than
  referencing the old structure.
- Use of the structured ceph_mds_request_head directly instead of the
  old one.

Additionally, this consolidation normalizes the handling of
request_head_version v1 to align with versions v2 and v3, leading to
a more consistent and maintainable codebase.

These changes simplify the codebase and reduce potential confusion
stemming from the existence of an obsolete structure.

Signed-off-by: Liang Jie <liangjie@lixiang.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-01-27 16:07:42 +01:00
Antoine Viallon
3b7d93db45 ceph: fix memory leak in ceph_mds_auth_match()
We now free the temporary target path substring allocation on every
possible branch, instead of omitting the default branch.  In some
cases, a memory leak occured, which could rapidly crash the system
(depending on how many file accesses were attempted).

This was detected in production because it caused a continuous memory
growth, eventually triggering kernel OOM and completely hard-locking
the kernel.

Relevant kmemleak stacktrace:

    unreferenced object 0xffff888131e69900 (size 128):
      comm "git", pid 66104, jiffies 4295435999
      hex dump (first 32 bytes):
        76 6f 6c 75 6d 65 73 2f 63 6f 6e 74 61 69 6e 65  volumes/containe
        72 73 2f 67 69 74 65 61 2f 67 69 74 65 61 2f 67  rs/gitea/gitea/g
      backtrace (crc 2f3bb450):
        [<ffffffffaa68fb49>] __kmalloc_noprof+0x359/0x510
        [<ffffffffc32bf1df>] ceph_mds_check_access+0x5bf/0x14e0 [ceph]
        [<ffffffffc3235722>] ceph_open+0x312/0xd80 [ceph]
        [<ffffffffaa7dd786>] do_dentry_open+0x456/0x1120
        [<ffffffffaa7e3729>] vfs_open+0x79/0x360
        [<ffffffffaa832875>] path_openat+0x1de5/0x4390
        [<ffffffffaa834fcc>] do_filp_open+0x19c/0x3c0
        [<ffffffffaa7e44a1>] do_sys_openat2+0x141/0x180
        [<ffffffffaa7e4945>] __x64_sys_open+0xe5/0x1a0
        [<ffffffffac2cc2f7>] do_syscall_64+0xb7/0x210
        [<ffffffffac400130>] entry_SYSCALL_64_after_hwframe+0x77/0x7f

It can be triggered by mouting a subdirectory of a CephFS filesystem,
and then trying to access files on this subdirectory with an auth token
using a path-scoped capability:

    $ ceph auth get client.services
    [client.services]
            key = REDACTED
            caps mds = "allow rw fsname=cephfs path=/volumes/"
            caps mon = "allow r fsname=cephfs"
            caps osd = "allow rw tag cephfs data=cephfs"

    $ cat /proc/self/mounts
    services@[REDACTED].cephfs=/volumes/containers /ceph/containers ceph rw,noatime,name=services,secret=<hidden>,ms_mode=prefer-crc,mount_timeout=300,acl,mon_addr=[REDACTED]:3300,recover_session=clean 0 0

    $ seq 1 1000000 | xargs -P32 --replace={} touch /ceph/containers/file-{} && \
    seq 1 1000000 | xargs -P32 --replace={} cat /ceph/containers/file-{}

[ idryomov: combine if statements, rename rc to path_matched and make
            it a bool, formatting ]

Cc: stable@vger.kernel.org
Fixes: 596afb0b89 ("ceph: add ceph_mds_check_access() helper")
Signed-off-by: Antoine Viallon <antoine@lesviallon.fr>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-01-15 20:35:06 +01:00
Max Kellermann
550f7ca98e ceph: give up on paths longer than PATH_MAX
If the full path to be built by ceph_mdsc_build_path() happens to be
longer than PATH_MAX, then this function will enter an endless (retry)
loop, effectively blocking the whole task.  Most of the machine
becomes unusable, making this a very simple and effective DoS
vulnerability.

I cannot imagine why this retry was ever implemented, but it seems
rather useless and harmful to me.  Let's remove it and fail with
ENAMETOOLONG instead.

Cc: stable@vger.kernel.org
Reported-by: Dario Weißer <dario@cure53.de>
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-12-16 23:25:43 +01:00
Max Kellermann
c5cf420303 ceph: fix cred leak in ceph_mds_check_access()
get_current_cred() increments the reference counter, but the
put_cred() call was missing.

Cc: stable@vger.kernel.org
Fixes: 596afb0b89 ("ceph: add ceph_mds_check_access() helper")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-11-25 15:51:13 +01:00
Max Kellermann
23426309a4 ceph: pass cred pointer to ceph_mds_auth_match()
This eliminates a redundant get_current_cred() call, because
ceph_mds_check_access() has already obtained this pointer.

As a side effect, this also fixes a reference leak in
ceph_mds_auth_match(): by omitting the get_current_cred() call, no
additional cred reference is taken.

Cc: stable@vger.kernel.org
Fixes: 596afb0b89 ("ceph: add ceph_mds_check_access() helper")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-11-25 15:51:13 +01:00
Patrick Donnelly
50f42c4895 ceph: correct ceph_mds_cap_item field name
The issue_seq is sent with bulk cap releases, not the current sequence
number. See also ceph.git commit 655cddb7c9f3 ("include/ceph_fs: correct
ceph_mds_cap_item field name").

Link: https://tracker.ceph.com/issues/66704
Signed-off-by: Patrick Donnelly <pdonnell@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-11-19 11:08:17 +01:00
Dmitry Antipov
3500000bb1 ceph: miscellaneous spelling fixes
Correct spelling here and there as suggested by codespell.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-11-18 17:34:36 +01:00
Dr. David Alan Gilbert
6025b482e4 ceph: Remove fs/ceph deadcode
ceph_caps_revoking() has been unused since 2017's commit
3fb99d483e ("ceph: nuke startsync op")

ceph_mdsc_open_export_target_sessions() has been unused since 2013's
commit 11df2dfb61 ("ceph: add imported caps when handling cap export message")

Remove them.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-11-18 17:34:35 +01:00
Yan Zhen
0039aebfe8 ceph: Fix typo in the comment
Correctly spelled comments make it easier for the reader to understand
the code.

replace 'tagert' with 'target' in the comment &
replace 'vaild' with 'valid' in the comment &
replace 'carefull' with 'careful' in the comment &
replace 'trsaverse' with 'traverse' in the comment.

Signed-off-by: Yan Zhen <yanzhen@vivo.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-09-24 22:51:33 +02:00
Luis Henriques (SUSE)
d97079e97e ceph: fix a memory leak on cap_auths in MDS client
The cap_auths that are allocated during an MDS session opening are never
released, causing a memory leak detected by kmemleak.  Fix this by freeing
the memory allocated when shutting down the MDS client.

Fixes: 1d17de9534 ("ceph: save cap_auths in MDS client when session is opened")
Signed-off-by: Luis Henriques (SUSE) <luis.henriques@linux.dev>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-09-24 22:51:33 +02:00
Xiubo Li
adc5246176 ceph: flush all caps releases when syncing the whole filesystem
We have hit a race between cap releases and cap revoke request
that will cause the check_caps() to miss sending a cap revoke ack
to MDS. And the client will depend on the cap release to release
that revoking caps, which could be delayed for some unknown reasons.

In Kclient we have figured out the RCA about race and we need
a way to explictly trigger this manually could help to get rid
of the caps revoke stuck issue.

Link: https://tracker.ceph.com/issues/67221
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-09-24 22:51:28 +02:00
Xiubo Li
c085f6ca95 ceph: rename ceph_flush_cap_releases() to ceph_flush_session_cap_releases()
Prepare for adding a helper to flush the cap releases for all
sessions.

Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-09-24 22:51:19 +02:00
Xiubo Li
578eb54c4a ceph: periodically flush the cap releases
The MDS could be waiting the caps releases infinitely in some corner
case and then reporting the caps revoke stuck warning. To fix this
we should periodically flush the cap releases.

Link: https://tracker.ceph.com/issues/57244
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Venky Shankar <vshankar@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-07-23 10:01:57 +02:00
Max Kellermann
65d284a38c ceph: use cap_wait_list only if debugfs is enabled
Only debugfs uses this list.  By omitting it, we save some memory and
reduce lock contention on `caps_list_lock`.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-07-23 10:01:57 +02:00
Xiubo Li
596afb0b89 ceph: add ceph_mds_check_access() helper
This will help check the mds auth access in client side. Always
insert the server path in front of the target path when matching
the paths.

[ idryomov: use u32 instead of uint32_t ]

Link: https://tracker.ceph.com/issues/61333
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Milind Changire <mchangir@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-05-23 10:35:46 +02:00
Xiubo Li
1d17de9534 ceph: save cap_auths in MDS client when session is opened
Save the cap_auths, which have been parsed by the MDS, in the opened
session.

[ idryomov: use s64 and u32 instead of int64_t and uint32_t, switch to
            bool for root_squash, readable and writeable ]

Link: https://tracker.ceph.com/issues/61333
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Milind Changire <mchangir@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-05-23 10:35:46 +02:00
Xiubo Li
17f8dc2db5 ceph: switch to use cap_delay_lock for the unlink delay list
The same list item will be used in both cap_delay_list and
cap_unlink_delay_list, so it's buggy to use two different locks
to protect them.

Cc: stable@vger.kernel.org
Fixes: dbc347ef7f ("ceph: add ceph_cap_unlink_work to fire check_caps() immediately")
Link: https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/thread/AODC76VXRAMXKLFDCTK4TKFDDPWUSCN5
Reported-by: Marc Ruhmann <ruhmann@luis.uni-hannover.de>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Tested-by: Marc Ruhmann <ruhmann@luis.uni-hannover.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-04-11 22:56:28 +02:00