kernel/git/next/linux-next.git/fs/ceph, branch master

Merge branch 'vfs.all' of https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git

2026-09-04T16:31:54+00:00

ceph: apply nearfull_sync option on remount

2026-09-02T10:23:05+00:00

ceph_parse_mount_param() stores nearfull_sync / nonearfull_sync on the temporary fs_context options, but ceph_reconfigure_fc() never copied CEPH_MOUNT_OPT_NEARFULL_SYNC onto the live mount. Remount therefore succeeded while writes and /proc/mounts kept the original-mount flag. Apply the flag the same way as ASYNC_DIROPS and SPARSEREAD so remount can enable or disable NEARFULL IOCB_DSYNC promotion. Fixes: c7a12c20bfba ("ceph: make nearfull sync writes opt-in") Signed-off-by: Alex Markuze Reviewed-by: Xiubo Li Signed-off-by: Ilya Dryomov

ceph: lock mutex in ceph_mds_check_access()

2026-09-02T10:22:03+00:00

MDS session OPEN handling replaces mdsc->s_cap_auths under mdsc->mutex, freeing the previous array and its strings. ceph_mds_check_access() traverses this array without holding the mutex. A concurrent session reopen can therefore free the array while it is being inspected, resulting in a use-after-free like this: Unable to handle kernel paging request at virtual address 003aaad64b2c8bb9 [...] Internal error: Oops: 0000000096000004 [#1] SMP Modules linked in: CPU: 56 UID: 2953037534 PID: 1253231 Comm: php-cgi8.4 Not tainted 6.18.45-i2-ampere #1146 NONE [..] pc : ceph_mds_check_access+0xd4/0x550 lr : ceph_mds_check_access+0xc8/0x550 [...] Call trace: ceph_mds_check_access+0xd4/0x550 (P) ceph_atomic_open+0x138/0xbe8 path_openat+0xa24/0xfa8 do_filp_open+0x94/0x158 do_sys_openat2+0x88/0xf8 Cc: stable@vger.kernel.org Fixes: 596afb0b8933 ("ceph: add ceph_mds_check_access() helper") Signed-off-by: Max Kellermann Reviewed-by: Alex Markuze Signed-off-by: Ilya Dryomov

vfs: move O_IS_MKDIR check from lookup_open() into individual filesystems

2026-08-31T08:32:26+00:00

Individual filesystems that implement ->atomic_open() need to get the chance to implement O_CREAT|O_DIRECTORY or not, rather than decide this at the VFS level in lookup_open(). Signed-off-by: Jori Koolstra Link: https://patch.msgid.link/20260823160706.358293-8-jkoolstra@xs4all.nl Signed-off-by: Christian Brauner (Amutable)

Merge tag 'ceph-for-7.3-rc1' of https://github.com/ceph/ceph-client

2026-08-28T18:51:05+00:00

Pull ceph updates from Ilya Dryomov: "A wide variety of mostly CephFS fixes and cleanups, split between changes that address edge cases (Sam, Xiubo, Matthew), efficiency improvements (Max) and AI-assisted hardening (Michael, Jeremy). One thing that stands out is Alex's change to how CephFS behaves in NEARFULL scenarios: the long-standing "make all writes synchronous" behavior has become opt-in. It was always somewhat controversial and doesn't make much sense for modern deployments; the new default is to continue normal operation (i.e. buffer writes as MDS allows, etc). The behavior in case the cluster reaches any FULL state remains the same as before" * tag 'ceph-for-7.3-rc1' of https://github.com/ceph/ceph-client: (32 commits) ceph: force a cap message when a deferred revoke can't be acked immediately libceph: reject buckets with mismatched CRUSH ids ceph: reject export_targets ranks >= CEPH_MAX_MDS in mdsmap decode ceph: fix leaked inode reference on writeback abort at umount libceph: remove ceph_put_page_vector() libceph: validate banner payload length ceph: make nearfull sync writes opt-in ceph: do not repeat ceph_trim_dentries() if no progress possible ceph: drop mdsc->mutex before decoding the MDS reply ceph: fix UAF in check_new_map() on session freed during unlock ceph: fix UAF in __kick_flushing_caps() on cf entry freed during unlock ceph: pass inode pointer around instead of reloading it ceph: mark cap remove with RB_CLEAR_NODE() instead of setting ci=NULL ceph: add helper function ceph_cap_is_removed() ceph: make __ceph_remove_cap() static ceph: cap delegated inode count in ceph_parse_deleg_inos() ceph: bound num_export_targets array for mds info v2/v3 ceph: bound MDSCapAuth path and fs_name decode in handle_session() ceph: bound xattr value length in __build_xattrs() ceph: bound copied dentry name length in NFS export get_name ...

ceph: force a cap message when a deferred revoke can't be acked immediately

2026-08-26T17:57:29+00:00

When the MDS revokes capabilities, handle_cap_grant() normally guarantees a response by setting `CHECK_CAPS_FLUSH_FORCE` (see commit 31634d7597d8 ("ceph: force sending a cap update msg back to MDS for revoke op")), so ceph_check_caps() sends a cap message even if the client would otherwise decide it has nothing to do. That guarantee is skipped whenever the revoke has to be deferred (via revoke_wait): revoking Fb while dirty data is still buffered (writeback is queued first) or revoking Fc while pages are cached (async invalidation is queued first). In those cases, the ack is left to the deferred completion (ceph_put_wrbuffer_cap_refs() after writeback, or the invalidate worker after invalidation); both of which call ceph_check_caps(ci,0) i.e. without `CHECK_CAPS_FLUSH_FORCE`. Nothing gets sent under one of the following conditions: - the inode is retaining caps because the file was used recently (file_wanted != 0; retain |= CEPH_CAP_ANY) - the revoked cap is still used because the page was re-cached (e.g. a file being re-read) - the MDS has meanwhile re-granted, so `issued==implemented` and the client sees nothing being revoked The client then never emits the cap message which the MDS is waiting for. The MDS blocks on the revoke indefinitely and logs, for minutes or hours: client.NNN isn't responding to mclientcaps(revoke), ino 0x... pending pAsxLsXsxFsxcrwb issued pAsxLsXsxFsxcrwb, sent 964.899182 seconds ago The client-side state at that point shows the full cap set still issued, nothing in the revoking/flushing sets. Thus nothing gets sent. This patch fixes it by remembering that a forced response is expected. When a revoke is deferred, set `CEPH_I_FLUSH_FORCE` on the inode. ceph_check_caps() replays it as `CHECK_CAPS_FLUSH_FORCE`, so whichever path re-checks the inode next (the writeback/invalidate completion, the delayed worker, or any other caller) is guaranteed to send a cap message to the MDS. __prep_cap() clears the flag once a message is actually built. This is the deferred-path counterpart of the existing `CHECK_CAPS_FLUSH_FORCE` handling; a normal (non-deferred) revoke still forces the response inline as before. Cc: stable@vger.kernel.org Fixes: 31634d7597d8 ("ceph: force sending a cap update msg back to MDS for revoke op") Fixes: 257e6172ab36 ("ceph: don't let check_caps skip sending responses for revoke msgs") Signed-off-by: Max Kellermann Reviewed-by: Alex Markuze Signed-off-by: Ilya Dryomov

ceph: reject export_targets ranks >= CEPH_MAX_MDS in mdsmap decode

2026-08-26T17:57:29+00:00

MDSMap export_targets entries are monitor controlled. check_new_map() uses each entry as a bit number in a fixed stack bitmap, so a rank outside the protocol namespace can make set_bit() write past the end of the array. Reject ranks outside CEPH_MAX_MDS while decoding the map. Do not validate against possible_max_rank here because maps may legitimately reference ranks beyond a temporarily reduced max_mds. Cc: stable@vger.kernel.org Fixes: d517b3983dd3 ("ceph: reconnect to the export targets on new mdsmaps") Signed-off-by: Jérémy Jean Reviewed-by: Alex Markuze Signed-off-by: Alex Markuze Signed-off-by: Ilya Dryomov

ceph: fix leaked inode reference on writeback abort at umount

2026-08-26T17:57:28+00:00

ceph_dirty_folio() takes a wrbuffer claim on each newly dirtied folio: it bumps i_wrbuffer_ref (taking an ihold() on the 0->1 transition) and attaches the snap_context to folio->private. That claim is released only by ceph_put_wrbuffer_cap_refs(), which for a submitted write runs from writepages_finish(). In ceph_submit_write(), if ceph_inc_osd_stopping_blocker() fails -- which happens during umount -- the request is aborted before submission: the already-collected folios are only redirtied and unlocked, so writepages_finish() never runs and the claim is leaked. redirty_page_for_writepage() -> folio_redirty_for_writepage() -> filemap_dirty_folio() sets PG_dirty directly and does not go through ->dirty_folio, so ceph_dirty_folio() is not re-entered to rebalance it. Because every subsequent writeback also fails the osd_stopping_blocker, i_wrbuffer_ref never returns to 0, the ihold() is never dropped, and the inode cannot be evicted: VFS: Busy inodes after unmount of ceph kernel BUG at fs/super.c:650! Release the orphaned claim in the abort path before redirtying, via ceph_undo_wrbuffer_claim(): detach the snap_context, drop the wrbuffer reference (letting i_wrbuffer_ref reach 0 and iput() the inode), and drop the snap_context reference -- i.e. do what writepages_finish() would have done for these never-submitted folios. Only the locked_pages entries are undone; folios still in the fbatch were never dirty-cleared by this call (folio_clear_dirty_for_io() is the ownership-transfer point, and a successful move NULLs the fbatch slot), so they hold no claim this call owns. Cc: stable@vger.kernel.org Fixes: fd7449d937e7 ("ceph: fix generic/421 test failure") Signed-off-by: Matthew Brown Reviewed-by: Xiubo Li Signed-off-by: Ilya Dryomov

libceph: remove ceph_put_page_vector()

2026-08-26T17:57:28+00:00

ceph_put_page_vector() was paired with ceph_get_direct_page_vector(), which was removed in commit 97a385e55829 ("libceph: remove ceph_get_direct_page_vector()"). Its only remaining caller, finish_netfs_read(), uses it to put a page vector allocated with iov_iter_get_pages_alloc2(), which is confusing. Open-code the put_page() loop and kvfree() there instead. The caller passed dirty = false, so this also removes the dead dirty branch and with it a call to the deprecated set_page_dirty_lock(). Signed-off-by: Tal Zussman Reviewed-by: Ilya Dryomov Signed-off-by: Ilya Dryomov

ceph: make nearfull sync writes opt-in

2026-08-26T17:57:28+00:00

The kernel CephFS client has historically treated a cluster or pool NEARFULL condition as a request to force successful writes through generic_write_sync(). That effectively turns otherwise buffered writes into synchronous writes and can cause a severe throughput drop as soon as a single OSD or the file data pool crosses the nearfull threshold. On modern large clusters, NEARFULL is primarily an operator health signal rather than an immediate client-side capacity failure. Operators can still have substantial usable capacity while a cluster is rebalancing, splitting PGs, or expanding onto new devices. RBD, RGW and the userspace CephFS client do not impose this extra client-side sync-write throttle, so the kernel client behavior is surprising and operationally painful. Change the default behavior so NEARFULL no longer changes normal write-sync semantics. FULL and pool FULL still fail with -ENOSPC, and explicitly synchronous writes continue to be synced by generic_write_sync(). Add a nearfull_sync mount option for deployments that want the legacy backpressure behavior. When this option is set, successful writes are promoted to IOCB_DSYNC if the cluster or file data pool is marked NEARFULL, preserving the old behavior for conservative deployments. Link: https://tracker.ceph.com/issues/74849 Signed-off-by: Alex Markuze Reviewed-by: Xiubo Li Signed-off-by: Ilya Dryomov