kernel/git/stable/linux.git/fs/afs, branch master

Merge tag 'vfs-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-08-17T19:56:12+00:00

Pull misc vfs updates from Christian Brauner: "Bigger cleanups: - The lockref dead-count handling is tidied up. The open-coded check for a count below zero as the dead marker relies on information the caller should not have. - make put_mnt_ns() leave mounts connected. Destroying a mount namespace disconnected its mounts from their mount points. So a file descriptor still open on the parent of a mount point could be used to peek under it. Locked mounts were already kept connected to prevent exactly that. But a mount is only locked when its tree is copied across a user namespace boundary. So a mount namespace set up by a privileged component had no locked mounts and its mounts were disconnected. Passing UMOUNT_CONNECTED keeps every mount connected and prevents that bug. - vfs_prepare_mode() passes S_IFDIR for directories. I meant to fix that ago but didn't get to it. So now someone finally did it. This kills the exception where the mode could be 0 when a directory was created whereas every other creation operation passed it explicitly already. - move long delayed work for ufs, jffs2, hfsplus, hfs and affs from the per-cpu system_long_wq to the new unbound system_dfl_long_wq. None of that work relies on per-cpu state and the work item is enqueued with queue_delayed_work() whose timer is global anyway. So it may as well benefit from scheduler task placement. Smaller fixes and cleanups: - unlock_buffer() and journal_end_buffer_io_sync() use clear_and_wake_up_bit() - the pipe page pools are unified into a single per-pipe pool and the extra wake_up(rd_wait) is limited to EPOLLET consumers - eventpoll now computes its timer slack lazily in ep_poll() - shrink_dcache_for_umount() keeps making progress on busy roots - excess xarray nodes are freed in clear_inode() - romfs detects hard link cycles - the user path of nested backing files is fixed - pidfd holds exec_update_lock around the namespace ioctl - non-memcg-aware nr_cached_objects is skipped during memcg slab shrink - iomap_write_iter() always returns status - mangle_path() is renamed to seq_mangle_path() - inode timestamp accessors are annotated - new regression test for pipe->poll_usage. - a few documentation, kernel-doc and selftest fixes" * tag 'vfs-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (67 commits) selftests/namespaces: Fix racy pipe handshake in timens and pidns_separate selftests/epoll: add a regression test for pipe->poll_usage pipe: only enable the extra wake_up(rd_wait) for EPOLLET consumers pidfd: hold exec_update_lock around namespace ioctl fs: fix user path of nested backing files fs: remove stale inode_insert5() kernel-doc parameter fs: fix switch/case indentation in sysfs() syscall fs: document semantics of kstat::{uid,gid} fields dcache: keep shrink_dcache_for_umount() making progress on busy roots seq_file: rename mangle_path to seq_mangle_path nstree: add/fix struct ns_id_req kernel-doc member fields dcache: use lockref routines for dead count checks lockref: tidy up dead count handling initramfs: fix typo in reserve_initrd_mem comment fs/pipe: unify the page pools into a single per-pipe pool fs: annotate inode timestamp accessors eventpoll: compute timer slack lazily in ep_poll() selftests/filesystems: add mntns cleanup test put_mnt_ns(): leave mounts connected affs: Move long delayed work on system_dfl_long_wq ...

Merge tag 'vfs-7.3-rc1.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-08-17T19:03:34+00:00

Pull vfs lookup updates from Christian Brauner: "This refactors lookup_open() and adds vfs_lookup_open() for nfsd. mnt_want_write() and parent locking are moved into lookup_open() itself. audit_inode_child() is also now called in lookup_open() on failure. That is the calling convention in vfs_create() and vfs_mkdir(), but lookup_open() made no such call when atomic_open() should have created a file and did not. And neither did the regular ->create() path fwiw. This also contains work to remove the unneeded excl argument from the ->create() inode op" * tag 'vfs-7.3-rc1.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs/namei.c: fix coding style in atomic_open() and lookup_open() fs/namei.c: fix kerneldoc of atomic_open() and vfs_lookup_open() fs/namei.c: update stale comments in lookup_open() Remove excl arg to ->create inode_operation fs/namei.c: update kerneldoc of atomic_open() vfs: call audit_inode_child() in lookup_open() on failure vfs: move create error && negative dentry case in lookup_open() up VFS: add vfs_lookup_open() for nfsd VFS: move delegated_inode retry loop into lookup_open() VFS: move mnt_want_write() and locking into lookup_open()

Remove excl arg to ->create inode_operation

2026-07-31T08:18:30+00:00

The only time that 'false' is passed as the 'excl' arg to the ->create inode_operation is in lookup_open() when ->atomic_open is not provided by the parent directory. *all* directory inode_operations which do not have ->atomic_open completely ignore the 'excl' arg. Therefore we don't need the 'excl' arg. Those few ->create operations which pay attention to the arg are only ever called with a value of 'true'. We remove that arg and change all ->create operations to behave as those thhe arg were 'true'. Signed-off-by: NeilBrown Link: https://patch.msgid.link/178290671516.27465.15984496764174914338@noble.neil.brown.name Reviewed-by: Jori Koolstra Reviewed-by: Jan Kara Signed-off-by: Christian Brauner (Amutable)

afs: Fix UAF when sending a message

2026-07-28T07:20:44+00:00

In afs_make_call(), there's a race with async call reception and destruction. If a call is dispatched that doesn't have call->write_iter set (used to specify the data content for FS.StoreData), then the first rxrpc_kernel_send_data() will not set MSG_MORE in the msghdr. Once rxrpc_send_data() queues the last request packet, the response could come in at any time and cause the call to be completed and put. However, afs_make_call() will look at the call again to see it ->write_iter should be handled - something it's only allowed to do if it has its own ref on the call. Whilst this is the case for synchronous calls, it isn't true for async calls such as FS.FetchData. There's also a potential UAF in afs_make_call() in the event that an asynchronous call is being sent, but the call fails in some way (e.g. it gets aborted from the server). The problem there is that afs_make_call() tries to abort a call if the rxrpc send fails, but the asynchronous notification from rxrpc may have caused the afs_call to be torn down. generic/650 plays games with randomly taking CPUs offline, and can interject a significant delay such that the call is deallocated before afs_make_call() gets to check call->write_iter - and a UAF ensues (caught by KASAN). BUG: KASAN: slab-use-after-free in afs_make_call+0x1c90/0x2210 [kafs] Read of size 8 at addr ffff888035e050e8 by task fsstress/1409 Fix this by making afs_make_op_call() give the op->call its own ref rather than transferring the caller's ref to it and then dropping the ref when afs_make_call() returns. This also means that the afs_make_call() func never loses its ref on the call now. Fixes: eddf51f2bb2c ("afs: Make {Y,}FS.FetchData an asynchronous operation") Fixes: e49c7b2f6de7 ("afs: Build an abstraction around an "operation" concept") Link: https://sashiko.dev/#/patchset/20260702144919.172295-1-dhowells%40redhat.com Reported-by: Marc Dionne Signed-off-by: David Howells Link: https://patch.msgid.link/20260723113452.566619-4-dhowells@redhat.com cc: Jeffrey Altman cc: linux-afs@lists.infradead.org cc: stable@kernel.org Signed-off-by: Christian Brauner (Amutable)

afs: Fix afs_fs_fetch_data() to subtract transferred from len

2026-07-28T07:20:44+00:00

Fix afs_fs_fetch_data() to subtract subreq->transferred from subreq->len rather than adding it. Fixes: f28fc2010d62 ("afs: Eliminate afs_read") Link: https://sashiko.dev/#/patchset/20260713081022.2186481-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260723113452.566619-3-dhowells@redhat.com cc: Marc Dionne cc: Jeffrey Altman cc: linux-afs@lists.infradead.org cc: stable@kernel.org Signed-off-by: Christian Brauner (Amutable)

afs: Fix afs_fs_fetch_data() to set call->async

2026-07-28T07:20:44+00:00

Fix afs_fs_fetch_data() to set call->async on an async operation as does afs_fs_fetch_data64(). Fixes: eddf51f2bb2c ("afs: Make {Y,}FS.FetchData an asynchronous operation") Link: https://sashiko.dev/#/patchset/20260702144919.172295-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260723113452.566619-2-dhowells@redhat.com cc: Marc Dionne cc: Jeffrey Altman cc: linux-afs@lists.infradead.org cc: stable@kernel.org Signed-off-by: Christian Brauner (Amutable)

afs: Fix afs_edit_dir_remove() to get, not find, block 0

2026-07-23T09:32:40+00:00

Fix afs_edit_dir_remove() to use afs_dir_get_block() to get block 0 rather than afs_dir_find_block() as the latter caches the found block in the afs_dir_iter and may[*] switch out the page it's on if another afs_dir_find_block() is done. This parallels what afs_edit_dir_add() does. [*] There's more than one block per page. Fixes: a5b5beebcf96 ("afs: Use the contained hashtable to search a directory") Closes: https://sashiko.dev/#/patchset/20260706153408.1231650-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/2380759.1783956175@warthog.procyon.org.uk cc: Marc Dionne cc: linux-afs@lists.infradead.org cc: linux-fsdevel@vger.kernel.org cc: stable@vger.kernel.org Signed-off-by: Christian Brauner (Amutable)

netfs: Replace wb_lock with a bit lock for asynchronicity

2026-07-01T13:26:29+00:00

The netfs_inode::wb_lock mutex is used to prevent multiple simultaneous writebacks from fighting each other (a writeback thread will write multiple discontiguous regions within the same request). The mutex, however, only serialises the issuing of subrequests; it doesn't serialise the collection of results, and, in particular, the updating of file size information and fscache populatedness data. Unfortunately, the mutex cannot be held around the entire process as it has to be unlocked in the same thread in which it is locked - and we don't want to hold up the allocator whilst we complete the writeback. Fix this by replacing the mutex with a bit flag and a list of lock waiters so that the lock can be dropped in the collector thread after collection is complete. Link: https://sashiko.dev/#/patchset/20260608145432.681865-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260625140640.3116900-12-dhowells@redhat.com cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner (Amutable)

afs: Fix unchecked-length string display in debug statement

2026-07-01T13:26:22+00:00

Fix afs_extract_vlserver_list() to limit the length of the displayed string in a debug statement(). Fixes: 0a5143f2f89c ("afs: Implement VL server rotation") Closes: https://sashiko.dev/#/patchset/20260618074903.2374756-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260622090856.2746629-22-dhowells@redhat.com cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: Christian Brauner (Amutable)

afs: Fix the volume AFS_VOLUME_RM_TREE is set on

2026-07-01T13:26:22+00:00

Fix afs_insert_volume_into_cell() to set AFS_VOLUME_RM_TREE on the volume replaced, not the new volume, as it's now removed from the cell's volume tree. This will cause the old volume to be removed from the tree twice and the new volume never to be removed. Fixes: 9a6b294ab496 ("afs: Fix use-after-free due to get/remove race in volume tree") Closes: https://sashiko.dev/#/patchset/20260618074903.2374756-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260622090856.2746629-21-dhowells@redhat.com cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: Christian Brauner (Amutable)