kernel/linux.git/fs/notify, branch v7.0.11

fsnotify: fix inode reference leak in fsnotify_recalc_mask()

2026-05-23T11:09:26+00:00

[ Upstream commit 4aca914ac152f5d055ddcb36704d1e539ac08977 ] fsnotify_recalc_mask() fails to handle the return value of __fsnotify_recalc_mask(), which may return an inode pointer that needs to be released via fsnotify_drop_object() when the connector's HAS_IREF flag transitions from set to cleared. This manifests as a hung task with the following call trace: INFO: task umount:1234 blocked for more than 120 seconds. Call Trace: __schedule schedule fsnotify_sb_delete generic_shutdown_super kill_anon_super cleanup_mnt task_work_run do_exit do_group_exit The race window that triggers the iref leak: Thread A (adding mark) Thread B (removing mark) ────────────────────── ──────────────────────── fsnotify_add_mark_locked(): fsnotify_add_mark_list(): spin_lock(conn->lock) add mark_B(evictable) to list spin_unlock(conn->lock) return /* ---- gap: no lock held ---- */ fsnotify_detach_mark(mark_A): spin_lock(mark_A->lock) clear ATTACHED flag on mark_A spin_unlock(mark_A->lock) fsnotify_put_mark(mark_A) fsnotify_recalc_mask(): spin_lock(conn->lock) __fsnotify_recalc_mask(): /* mark_A skipped: ATTACHED cleared */ /* only mark_B(evictable) remains */ want_iref = false has_iref = true /* not yet cleared */ -> HAS_IREF transitions true -> false -> returns inode pointer spin_unlock(conn->lock) /* BUG: return value discarded! * iput() and fsnotify_put_sb_watched_objects() * are never called */ Fix this by deferring the transition true -> false of HAS_IREF flag from fsnotify_recalc_mask() (Thread A) to fsnotify_put_mark() (thread B). Fixes: c3638b5b1374 ("fsnotify: allow adding an inode mark without pinning inode") Signed-off-by: Xin Yin Signed-off-by: Amir Goldstein Link: https://patch.msgid.link/CAOQ4uxiPsbHb0o5voUKyPFMvBsDkG914FYDcs4C5UpBMNm0Vcg@mail.gmail.com Signed-off-by: Jan Kara Signed-off-by: Sasha Levin

fanotify: call fanotify_events_supported() before path_permission() and security_path_notify()

2026-05-23T11:08:56+00:00

[ Upstream commit 66052a768d4726a31e939b5ac902f2b0b452c8d5 ] The latter trigger LSM (e.g. SELinux) checks, which will log a denial when permission is denied, so it's better to do them after validity checks to avoid logging a denial when the operation would fail anyway. Fixes: 0b3b094ac9a7 ("fanotify: Disallow permission events for proc filesystem") Signed-off-by: Ondrej Mosnacek Reviewed-by: Amir Goldstein Reviewed-by: Paul Moore Link: https://patch.msgid.link/20260216150625.793013-3-omosnace@redhat.com Signed-off-by: Jan Kara Signed-off-by: Sasha Levin

fanotify: avoid/silence premature LSM capability checks

2026-05-23T11:08:56+00:00

[ Upstream commit 0d5ee3373426395478c355f3e93ba4b1118a04e9 ] Make sure calling capable()/ns_capable() actually leads to access denied when false is returned, because these functions emit an audit record when a Linux Security Module denies the capability, which makes it difficult to avoid allowing/silencing unnecessary permissions in security policies (namely with SELinux). Where the return value just used to set a flag, use the non-auditing ns_capable_noaudit() instead. Fixes: 7cea2a3c505e ("fanotify: support limited functionality for unprivileged users") Signed-off-by: Ondrej Mosnacek Reviewed-by: Paul Moore Reviewed-by: Amir Goldstein Link: https://patch.msgid.link/20260216150625.793013-2-omosnace@redhat.com Signed-off-by: Jan Kara Signed-off-by: Sasha Levin

fanotify: fix false positive on permission events

2026-05-14T13:31:07+00:00

commit 7746e3bd4cc19b5092e00d32d676e329bfcb6900 upstream. fsnotify_get_mark_safe() may return false for a mark on an unrelated group, which results in bypassing the permission check. Fix by skipping over detached marks that are not in the current group. CC: stable@vger.kernel.org Fixes: abc77577a669 ("fsnotify: Provide framework for dropping SRCU lock in ->handle_event") Signed-off-by: Miklos Szeredi Link: https://patch.msgid.link/20260410144950.156160-1-mszeredi@redhat.com Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman

inotify: fix watch count leak when fsnotify_add_inode_mark_locked() fails

2026-05-07T04:14:10+00:00

commit 6a320935fa4293e9e599ec9f85dc9eb3be7029f8 upstream. When fsnotify_add_inode_mark_locked() fails in inotify_new_watch(), the error path calls inotify_remove_from_idr() but does not call dec_inotify_watches() to undo the preceding inc_inotify_watches(). This leaks a watch count, and repeated failures can exhaust the max_user_watches limit with -ENOSPC even when no watches are active. Prior to commit 1cce1eea0aff ("inotify: Convert to using per-namespace limits"), the watch count was incremented after fsnotify_add_mark_locked() succeeded, so this path was not affected. The conversion moved inc_inotify_watches() before the mark insertion without adding the corresponding rollback. Add the missing dec_inotify_watches() call in the error path. Fixes: 1cce1eea0aff ("inotify: Convert to using per-namespace limits") Cc: stable@vger.kernel.org Signed-off-by: Chia-Ming Chang Signed-off-by: robbieko Reviewed-by: Nikolay Borisov Link: https://patch.msgid.link/20260224093442.3076294-1-chiamingc@synology.com Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

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

fsnotify: Use connector list for destroying inode marks

2026-01-23T12:26:37+00:00

Instead of iterating all inodes belonging to a superblock to find inode marks and remove them on umount, iterate all inode connectors for the superblock. This may be substantially faster since there are generally much less inodes with fsnotify marks than all inodes. It also removes one use of sb->s_inodes list which we strive to ultimately remove. Reviewed-by: Amir Goldstein Reviewed-by: Christian Brauner Signed-off-by: Jan Kara

fsnotify: Track inode connectors for a superblock

2026-01-23T12:26:20+00:00

Introduce a linked list tracking all inode connectors for a superblock. We will use this list when the superblock is getting shutdown to properly clean up all the inode marks instead of relying on scanning all inodes in the superblock which can get rather slow. Suggested-by: Amir Goldstein Reviewed-by: Amir Goldstein Reviewed-by: Christian Brauner Signed-off-by: Jan Kara

Merge tag 'fsnotify_for_v6.19-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2025-12-18T19:41:17+00:00

Pull fsnotify fixes from Jan Kara: "Two fsnotify fixes. The fix from Ahelenia makes sure we generate event when modifying inode flags, the fix from Amir disables sending of events from device inodes to their parent directory as it could concievably create a usable side channel attack in case of some devices and so far we aren't aware of anybody depending on the functionality" * tag 'fsnotify_for_v6.19-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fs: send fsnotify_xattr()/IN_ATTRIB from vfs_fileattr_set()/chattr(1) fsnotify: do not generate ACCESS/MODIFY events on child for special files