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, 35 insertions, 0 deletions

diff --git a/security/selinux/include/ibpkey.h b/security/selinux/include/ibpkey.h
new file mode 100644
index 000000000..875b05584
--- /dev/null
+++ b/security/selinux/include/ibpkey.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * pkey table
+ *
+ * SELinux must keep a mapping of pkeys to labels/SIDs.  This
+ * mapping is maintained as part of the normal policy but a fast cache is
+ * needed to reduce the lookup overhead.
+ */
+
+/*
+ * (c) Mellanox Technologies, 2016
+ */
+
+#ifndef _SELINUX_IB_PKEY_H
+#define _SELINUX_IB_PKEY_H
+
+#include <linux/types.h>
+#include "flask.h"
+
+#ifdef CONFIG_SECURITY_INFINIBAND
+void sel_ib_pkey_flush(void);
+int sel_ib_pkey_sid(u64 subnet_prefix, u16 pkey, u32 *sid);
+#else
+static inline void sel_ib_pkey_flush(void)
+{
+	return;
+}
+static inline int sel_ib_pkey_sid(u64 subnet_prefix, u16 pkey, u32 *sid)
+{
+	*sid = SECINITSID_UNLABELED;
+	return 0;
+}
+#endif
+
+#endif