Merge tag 'vfs-6.10-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs fixes from Christian Brauner:
 "cachefiles:

   - Export an existing and add a new cachefile helper to be used in
     filesystems to fix reference count bugs

   - Use the newly added fscache_ty_get_volume() helper to get a
     reference count on an fscache_volume to handle volumes that are
     about to be removed cleanly

   - After withdrawing a fscache_cache via FSCACHE_CACHE_IS_WITHDRAWN
     wait for all ongoing cookie lookups to complete and for the object
     count to reach zero

   - Propagate errors from vfs_getxattr() to avoid an infinite loop in
     cachefiles_check_volume_xattr() because it keeps seeing ESTALE

   - Don't send new requests when an object is dropped by raising
     CACHEFILES_ONDEMAND_OJBSTATE_DROPPING

   - Cancel all requests for an object that is about to be dropped

   - Wait for the ondemand_boject_worker to finish before dropping a
     cachefiles object to prevent use-after-free

   - Use cyclic allocation for message ids to better handle id recycling

   - Add missing lock protection when iterating through the xarray when
     polling

  netfs:

   - Use standard logging helpers for debug logging

  VFS:

   - Fix potential use-after-free in file locks during
     trace_posix_lock_inode(). The tracepoint could fire while another
     task raced it and freed the lock that was requested to be traced

   - Only increment the nr_dentry_negative counter for dentries that are
     present on the superblock LRU. Currently, DCACHE_LRU_LIST list is
     used to detect this case. However, the flag is also raised in
     combination with DCACHE_SHRINK_LIST to indicate that dentry->d_lru
     is used. So checking only DCACHE_LRU_LIST will lead to wrong
     nr_dentry_negative count. Fix the check to not count dentries that
     are on a shrink related list

  Misc:

   - hfsplus: fix an uninitialized value issue in copy_name

   - minix: fix minixfs_rename with HIGHMEM. It still uses kunmap() even
     though we switched it to kmap_local_page() a while ago"

* tag 'vfs-6.10-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  minixfs: Fix minixfs_rename with HIGHMEM
  hfsplus: fix uninit-value in copy_name
  vfs: don't mod negative dentry count when on shrinker list
  filelock: fix potential use-after-free in posix_lock_inode
  cachefiles: add missing lock protection when polling
  cachefiles: cyclic allocation of msg_id to avoid reuse
  cachefiles: wait for ondemand_object_worker to finish when dropping object
  cachefiles: cancel all requests for the object that is being dropped
  cachefiles: stop sending new request when dropping object
  cachefiles: propagate errors from vfs_getxattr() to avoid infinite loop
  cachefiles: fix slab-use-after-free in cachefiles_withdraw_cookie()
  cachefiles: fix slab-use-after-free in fscache_withdraw_volume()
  netfs, fscache: export fscache_put_volume() and add fscache_try_get_volume()
  netfs: Switch debug logging to pr_debug()

2 files changed, 10 insertions, 0 deletions

diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h
index bdf7f3eddf0a..4c91a019972b 100644
--- a/include/linux/fscache-cache.h
+++ b/include/linux/fscache-cache.h
@@ -19,6 +19,7 @@
 enum fscache_cache_trace;
 enum fscache_cookie_trace;
 enum fscache_access_trace;
+enum fscache_volume_trace;
 
 enum fscache_cache_state {
 	FSCACHE_CACHE_IS_NOT_PRESENT,	/* No cache is present for this name */
@@ -97,6 +98,11 @@ extern void fscache_withdraw_cookie(struct fscache_cookie *cookie);
 
 extern void fscache_io_error(struct fscache_cache *cache);
 
+extern struct fscache_volume *
+fscache_try_get_volume(struct fscache_volume *volume,
+		       enum fscache_volume_trace where);
+extern void fscache_put_volume(struct fscache_volume *volume,
+			       enum fscache_volume_trace where);
 extern void fscache_end_volume_access(struct fscache_volume *volume,
 				      struct fscache_cookie *cookie,
 				      enum fscache_access_trace why);
diff --git a/include/trace/events/fscache.h b/include/trace/events/fscache.h
index a6190aa1b406..f1a73aa83fbb 100644
--- a/include/trace/events/fscache.h
+++ b/include/trace/events/fscache.h
@@ -35,12 +35,14 @@ enum fscache_volume_trace {
 	fscache_volume_get_cookie,
 	fscache_volume_get_create_work,
 	fscache_volume_get_hash_collision,
+	fscache_volume_get_withdraw,
 	fscache_volume_free,
 	fscache_volume_new_acquire,
 	fscache_volume_put_cookie,
 	fscache_volume_put_create_work,
 	fscache_volume_put_hash_collision,
 	fscache_volume_put_relinquish,
+	fscache_volume_put_withdraw,
 	fscache_volume_see_create_work,
 	fscache_volume_see_hash_wake,
 	fscache_volume_wait_create_work,
@@ -120,12 +122,14 @@ enum fscache_access_trace {
 	EM(fscache_volume_get_cookie,		"GET cook ")		\
 	EM(fscache_volume_get_create_work,	"GET creat")		\
 	EM(fscache_volume_get_hash_collision,	"GET hcoll")		\
+	EM(fscache_volume_get_withdraw,		"GET withd")            \
 	EM(fscache_volume_free,			"FREE     ")		\
 	EM(fscache_volume_new_acquire,		"NEW acq  ")		\
 	EM(fscache_volume_put_cookie,		"PUT cook ")		\
 	EM(fscache_volume_put_create_work,	"PUT creat")		\
 	EM(fscache_volume_put_hash_collision,	"PUT hcoll")		\
 	EM(fscache_volume_put_relinquish,	"PUT relnq")		\
+	EM(fscache_volume_put_withdraw,		"PUT withd")            \
 	EM(fscache_volume_see_create_work,	"SEE creat")		\
 	EM(fscache_volume_see_hash_wake,	"SEE hwake")		\
 	E_(fscache_volume_wait_create_work,	"WAIT crea")