From 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 2 Sep 2026 15:31:14 -0700 Subject: treewide: refresh kmalloc_obj() conversions This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook --- fs/afs/callback.c | 262 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 262 insertions(+) create mode 100644 fs/afs/callback.c (limited to 'fs/afs/callback.c') diff --git a/fs/afs/callback.c b/fs/afs/callback.c new file mode 100644 index 000000000..61354003c --- /dev/null +++ b/fs/afs/callback.c @@ -0,0 +1,262 @@ +/* + * Copyright (c) 2002, 2007 Red Hat, Inc. All rights reserved. + * + * This software may be freely redistributed under the terms of the + * GNU General Public License. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Authors: David Woodhouse + * David Howells + * + */ + +#include +#include +#include +#include +#include +#include "internal.h" + +/* + * Handle invalidation of an mmap'd file. We invalidate all the PTEs referring + * to the pages in this file's pagecache, forcing the kernel to go through + * ->fault() or ->page_mkwrite() - at which point we can handle invalidation + * more fully. + */ +void afs_invalidate_mmap_work(struct work_struct *work) +{ + struct afs_vnode *vnode = container_of(work, struct afs_vnode, cb_work); + + unmap_mapping_pages(vnode->netfs.inode.i_mapping, 0, 0, false); +} + +static void afs_volume_init_callback(struct afs_volume *volume) +{ + struct afs_vnode *vnode; + + down_read(&volume->open_mmaps_lock); + + list_for_each_entry(vnode, &volume->open_mmaps, cb_mmap_link) { + if (vnode->cb_v_check != atomic_read(&volume->cb_v_break)) { + afs_clear_cb_promise(vnode, afs_cb_promise_clear_vol_init_cb); + queue_work(system_dfl_wq, &vnode->cb_work); + } + } + + up_read(&volume->open_mmaps_lock); +} + +/* + * Allow the fileserver to request callback state (re-)initialisation. + * Unfortunately, UUIDs are not guaranteed unique. + */ +void afs_init_callback_state(struct afs_server *server) +{ + struct afs_server_entry *se; + + down_read(&server->cell->vs_lock); + + list_for_each_entry(se, &server->volumes, slink) { + se->cb_expires_at = AFS_NO_CB_PROMISE; + se->volume->cb_expires_at = AFS_NO_CB_PROMISE; + trace_afs_cb_v_break(se->volume->vid, atomic_read(&se->volume->cb_v_break), + afs_cb_break_for_s_reinit); + if (!list_empty(&se->volume->open_mmaps)) + afs_volume_init_callback(se->volume); + } + + up_read(&server->cell->vs_lock); +} + +/* + * actually break a callback + */ +void __afs_break_callback(struct afs_vnode *vnode, enum afs_cb_break_reason reason) +{ + _enter(""); + + clear_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags); + if (afs_clear_cb_promise(vnode, afs_cb_promise_clear_cb_break)) { + vnode->cb_break++; + vnode->cb_v_check = atomic_read(&vnode->volume->cb_v_break); + afs_clear_permits(vnode); + + if (vnode->lock_state == AFS_VNODE_LOCK_WAITING_FOR_CB) + afs_lock_may_be_available(vnode); + + if (reason != afs_cb_break_for_deleted && + vnode->status.type == AFS_FTYPE_FILE && + atomic_read(&vnode->cb_nr_mmap)) + queue_work(system_dfl_wq, &vnode->cb_work); + + trace_afs_cb_break(&vnode->fid, vnode->cb_break, reason, true); + } else { + trace_afs_cb_break(&vnode->fid, vnode->cb_break, reason, false); + } +} + +void afs_break_callback(struct afs_vnode *vnode, enum afs_cb_break_reason reason) +{ + write_seqlock(&vnode->cb_lock); + __afs_break_callback(vnode, reason); + write_sequnlock(&vnode->cb_lock); +} + +/* + * Look up a volume by volume ID under RCU conditions. + */ +static struct afs_volume *afs_lookup_volume_rcu(struct afs_cell *cell, + afs_volid_t vid) +{ + struct afs_volume *volume = NULL; + struct rb_node *p; + + scoped_seqlock_read(&cell->volume_lock, ss_lock) { + /* Unfortunately, rbtree walking doesn't give reliable results + * under just the RCU read lock, so we have to check for + * changes. + */ + p = rcu_dereference_raw(cell->volumes.rb_node); + while (p) { + volume = rb_entry(p, struct afs_volume, cell_node); + + if (volume->vid < vid) + p = rcu_dereference_raw(p->rb_left); + else if (volume->vid > vid) + p = rcu_dereference_raw(p->rb_right); + else + break; + volume = NULL; + } + + if (volume && afs_try_get_volume(volume, afs_volume_trace_get_callback)) + break; + volume = NULL; + } + + return volume; +} + +/* + * Allow the fileserver to break callbacks at the volume-level. This is + * typically done when, for example, a R/W volume is snapshotted to a R/O + * volume (the only way to change an R/O volume). It may also, however, happen + * when a volserver takes control of a volume (offlining it, moving it, etc.). + * + * Every file in that volume will need to be reevaluated. + */ +static void afs_break_volume_callback(struct afs_server *server, + struct afs_volume *volume) + __releases(RCU) +{ + struct afs_server_list *slist = rcu_dereference(volume->servers); + unsigned int i, cb_v_break; + + write_lock(&volume->cb_v_break_lock); + + for (i = 0; i < slist->nr_servers; i++) + if (slist->servers[i].server == server) + slist->servers[i].cb_expires_at = AFS_NO_CB_PROMISE; + volume->cb_expires_at = AFS_NO_CB_PROMISE; + + cb_v_break = atomic_inc_return_release(&volume->cb_v_break); + trace_afs_cb_v_break(volume->vid, cb_v_break, afs_cb_break_for_volume_callback); + + write_unlock(&volume->cb_v_break_lock); + rcu_read_unlock(); + + if (!list_empty(&volume->open_mmaps)) + afs_volume_init_callback(volume); +} + +/* + * allow the fileserver to explicitly break one callback + * - happens when + * - the backing file is changed + * - a lock is released + */ +static void afs_break_one_callback(struct afs_server *server, + struct afs_volume *volume, + struct afs_fid *fid) +{ + struct super_block *sb; + struct afs_vnode *vnode; + struct inode *inode; + + /* See if we can find a matching inode - even an I_NEW inode needs to + * be marked as it can have its callback broken before we finish + * setting up the local inode. + */ + sb = rcu_dereference(volume->sb); + if (!sb) + return; + + inode = find_inode_rcu(sb, fid->vnode, afs_ilookup5_test_by_fid, fid); + if (inode) { + vnode = AFS_FS_I(inode); + afs_break_callback(vnode, afs_cb_break_for_callback); + } else { + trace_afs_cb_miss(fid, afs_cb_break_for_callback); + } +} + +static void afs_break_some_callbacks(struct afs_server *server, + struct afs_callback_break *cbb, + size_t *_count) +{ + struct afs_callback_break *residue = cbb; + struct afs_volume *volume; + afs_volid_t vid = cbb->fid.vid; + size_t i; + + rcu_read_lock(); + volume = afs_lookup_volume_rcu(server->cell, vid); + if (!volume) { + /* Ignore breaks on unknown volumes. */ + rcu_read_unlock(); + *_count = 0; + } else if (cbb->fid.vnode == 0 && cbb->fid.unique == 0) { + afs_break_volume_callback(server, volume); + *_count -= 1; + if (*_count) + memmove(cbb, cbb + 1, sizeof(*cbb) * *_count); + } else { + /* TODO: Find all matching volumes if we couldn't match the server and + * break them anyway. + */ + + for (i = *_count; i > 0; cbb++, i--) { + if (cbb->fid.vid == vid) { + _debug("- Fid { vl=%08llx n=%llu u=%u }", + cbb->fid.vid, + cbb->fid.vnode, + cbb->fid.unique); + --*_count; + if (volume) + afs_break_one_callback(server, volume, &cbb->fid); + } else { + *residue++ = *cbb; + } + } + rcu_read_unlock(); + } + + afs_put_volume(volume, afs_volume_trace_put_callback); +} + +/* + * allow the fileserver to break callback promises + */ +void afs_break_callbacks(struct afs_server *server, size_t count, + struct afs_callback_break *callbacks) +{ + _enter("%p,%zu,", server, count); + + ASSERT(server != NULL); + + while (count > 0) + afs_break_some_callbacks(server, callbacks, &count); +} -- cgit v1.3.1