From 506ada89629ec7059b96ecfb0dc7d33ece0103ca Mon Sep 17 00:00:00 2001
From: Eduard Zingerman <eddyz87@gmail.com>
Date: Fri, 4 Sep 2026 17:05:56 -0700
Subject: bpf: mark a NULL kfunc argument precise

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 fs/notify/fsnotify.h | 114 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 114 insertions(+)
 create mode 100644 fs/notify/fsnotify.h

(limited to 'fs/notify/fsnotify.h')

diff --git a/fs/notify/fsnotify.h b/fs/notify/fsnotify.h
new file mode 100644
index 000000000..58c7bb25e
--- /dev/null
+++ b/fs/notify/fsnotify.h
@@ -0,0 +1,114 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __FS_NOTIFY_FSNOTIFY_H_
+#define __FS_NOTIFY_FSNOTIFY_H_
+
+#include <linux/list.h>
+#include <linux/fsnotify.h>
+#include <linux/srcu.h>
+#include <linux/types.h>
+
+#include "../mount.h"
+
+/*
+ * fsnotify_connp_t is what we embed in objects which connector can be attached
+ * to.
+ */
+typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t;
+
+static inline struct inode *fsnotify_conn_inode(
+				struct fsnotify_mark_connector *conn)
+{
+	return conn->obj;
+}
+
+static inline struct mount *fsnotify_conn_mount(
+				struct fsnotify_mark_connector *conn)
+{
+	return real_mount(conn->obj);
+}
+
+static inline struct super_block *fsnotify_conn_sb(
+				struct fsnotify_mark_connector *conn)
+{
+	return conn->obj;
+}
+
+static inline struct mnt_namespace *fsnotify_conn_mntns(
+				struct fsnotify_mark_connector *conn)
+{
+	return conn->obj;
+}
+
+static inline struct super_block *fsnotify_object_sb(void *obj,
+			enum fsnotify_obj_type obj_type)
+{
+	switch (obj_type) {
+	case FSNOTIFY_OBJ_TYPE_INODE:
+		return ((struct inode *)obj)->i_sb;
+	case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
+		return ((struct vfsmount *)obj)->mnt_sb;
+	case FSNOTIFY_OBJ_TYPE_SB:
+		return (struct super_block *)obj;
+	default:
+		return NULL;
+	}
+}
+
+static inline struct super_block *fsnotify_connector_sb(
+				struct fsnotify_mark_connector *conn)
+{
+	return fsnotify_object_sb(conn->obj, conn->type);
+}
+
+static inline fsnotify_connp_t *fsnotify_sb_marks(struct super_block *sb)
+{
+	struct fsnotify_sb_info *sbinfo = fsnotify_sb_info(sb);
+
+	return sbinfo ? &sbinfo->sb_marks : NULL;
+}
+
+/* destroy all events sitting in this groups notification queue */
+extern void fsnotify_flush_notify(struct fsnotify_group *group);
+
+/* protects reads of inode and vfsmount marks list */
+extern struct srcu_struct fsnotify_mark_srcu;
+
+/* compare two groups for sorting of marks lists */
+extern int fsnotify_compare_groups(struct fsnotify_group *a,
+				   struct fsnotify_group *b);
+
+/* Destroy all inode marks for given superblock */
+void fsnotify_unmount_inodes(struct fsnotify_sb_info *sbinfo);
+
+/* Destroy all marks attached to an object via connector */
+extern void fsnotify_destroy_marks(fsnotify_connp_t *connp);
+/* run the list of all marks associated with inode and destroy them */
+static inline void fsnotify_clear_marks_by_inode(struct inode *inode)
+{
+	fsnotify_destroy_marks(&inode->i_fsnotify_marks);
+}
+/* run the list of all marks associated with vfsmount and destroy them */
+static inline void fsnotify_clear_marks_by_mount(struct vfsmount *mnt)
+{
+	fsnotify_destroy_marks(&real_mount(mnt)->mnt_fsnotify_marks);
+}
+/* run the list of all marks associated with sb and destroy them */
+static inline void fsnotify_clear_marks_by_sb(struct super_block *sb)
+{
+	fsnotify_destroy_marks(fsnotify_sb_marks(sb));
+}
+
+static inline void fsnotify_clear_marks_by_mntns(struct mnt_namespace *mntns)
+{
+	fsnotify_destroy_marks(&mntns->n_fsnotify_marks);
+}
+
+/*
+ * update the dentry->d_flags of all of inode's children to indicate if inode cares
+ * about events that happen to its children.
+ */
+extern void fsnotify_set_children_dentry_flags(struct inode *inode);
+
+void fsnotify_init_connector_caches(void);
+
+#endif	/* __FS_NOTIFY_FSNOTIFY_H_ */
-- 
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