bpf: mark a NULL kfunc argument precisegrafted

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>

1 files changed, 32 insertions, 0 deletions

diff --git a/security/selinux/include/ima.h b/security/selinux/include/ima.h
new file mode 100644
index 000000000..d7d18f030
--- /dev/null
+++ b/security/selinux/include/ima.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2021 Microsoft Corporation
+ *
+ * Author: Lakshmi Ramasubramanian (nramas@linux.microsoft.com)
+ *
+ * Measure critical data structures maintained by SELinux
+ * using IMA subsystem.
+ */
+
+#ifndef _SELINUX_IMA_H_
+#define _SELINUX_IMA_H_
+
+#include "security.h"
+
+#ifdef CONFIG_IMA
+void __init selinux_ima_config_len_init(void);
+extern void selinux_ima_measure_state(void);
+extern void selinux_ima_measure_state_locked(void);
+#else
+static inline void selinux_ima_config_len_init(void)
+{
+}
+static inline void selinux_ima_measure_state(void)
+{
+}
+static inline void selinux_ima_measure_state_locked(void)
+{
+}
+#endif
+
+#endif /* _SELINUX_IMA_H_ */