Merge tag 'hardening-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull hardening updates from Kees Cook:
 "One notable addition is the creation of the 'transitional' keyword for
  kconfig so CONFIG renaming can go more smoothly.

  This has been a long-standing deficiency, and with the renaming of
  CONFIG_CFI_CLANG to CONFIG_CFI (since GCC will soon have KCFI
  support), this came up again.

  The breadth of the diffstat is mainly this renaming.

   - Clean up usage of TRAILING_OVERLAP() (Gustavo A. R. Silva)

   - lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
     (Junjie Cao)

   - Add str_assert_deassert() helper (Lad Prabhakar)

   - gcc-plugins: Remove TODO_verify_il for GCC >= 16

   - kconfig: Fix BrokenPipeError warnings in selftests

   - kconfig: Add transitional symbol attribute for migration support

   - kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI"

* tag 'hardening-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  lib/string_choices: Add str_assert_deassert() helper
  kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
  kconfig: Add transitional symbol attribute for migration support
  kconfig: Fix BrokenPipeError warnings in selftests
  gcc-plugins: Remove TODO_verify_il for GCC >= 16
  stddef: Introduce __TRAILING_OVERLAP()
  stddef: Remove token-pasting in TRAILING_OVERLAP()
  lkdtm: fortify: Fix potential NULL dereference on kmalloc failure

6 files changed, 35 insertions, 13 deletions

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index ae2d2359b79e..a65a87366c48 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -157,7 +157,7 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG)
 #define PATCHABLE_DISCARDS	*(__patchable_function_entries)
 #endif
 
-#ifndef CONFIG_ARCH_SUPPORTS_CFI_CLANG
+#ifndef CONFIG_ARCH_SUPPORTS_CFI
 /*
  * Simply points to ftrace_stub, but with the proper protocol.
  * Defined by the linker script in linux/vmlinux.lds.h
diff --git a/include/linux/cfi.h b/include/linux/cfi.h
index 52a98886a455..1fd22ea6eba4 100644
--- a/include/linux/cfi.h
+++ b/include/linux/cfi.h
@@ -11,7 +11,7 @@
 #include <linux/module.h>
 #include <asm/cfi.h>
 
-#ifdef CONFIG_CFI_CLANG
+#ifdef CONFIG_CFI
 extern bool cfi_warn;
 
 enum bug_trap_type report_cfi_failure(struct pt_regs *regs, unsigned long addr,
@@ -52,7 +52,7 @@ static inline u32 cfi_get_func_hash(void *func)
 extern u32 cfi_bpf_hash;
 extern u32 cfi_bpf_subprog_hash;
 
-#else /* CONFIG_CFI_CLANG */
+#else /* CONFIG_CFI */
 
 static inline int cfi_get_offset(void) { return 0; }
 static inline u32 cfi_get_func_hash(void *func) { return 0; }
@@ -60,7 +60,7 @@ static inline u32 cfi_get_func_hash(void *func) { return 0; }
 #define cfi_bpf_hash 0U
 #define cfi_bpf_subprog_hash 0U
 
-#endif /* CONFIG_CFI_CLANG */
+#endif /* CONFIG_CFI */
 
 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
 bool is_cfi_trap(unsigned long addr);
diff --git a/include/linux/cfi_types.h b/include/linux/cfi_types.h
index 685f7181780f..a86af9bc8bdc 100644
--- a/include/linux/cfi_types.h
+++ b/include/linux/cfi_types.h
@@ -8,7 +8,7 @@
 #ifdef __ASSEMBLY__
 #include <linux/linkage.h>
 
-#ifdef CONFIG_CFI_CLANG
+#ifdef CONFIG_CFI
 /*
  * Use the __kcfi_typeid_<function> type identifier symbol to
  * annotate indirectly called assembly functions. The compiler emits
@@ -29,12 +29,12 @@
 #define SYM_TYPED_START(name, linkage, align...)	\
 	SYM_TYPED_ENTRY(name, linkage, align)
 
-#else /* CONFIG_CFI_CLANG */
+#else /* CONFIG_CFI */
 
 #define SYM_TYPED_START(name, linkage, align...)	\
 	SYM_START(name, linkage, align)
 
-#endif /* CONFIG_CFI_CLANG */
+#endif /* CONFIG_CFI */
 
 #ifndef SYM_TYPED_FUNC_START
 #define SYM_TYPED_FUNC_START(name) 			\
@@ -43,7 +43,7 @@
 
 #else /* __ASSEMBLY__ */
 
-#ifdef CONFIG_CFI_CLANG
+#ifdef CONFIG_CFI
 #define DEFINE_CFI_TYPE(name, func)						\
 	/*									\
 	 * Force a reference to the function so the compiler generates		\
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 64ff73c533e5..5b45ea7dff3e 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -248,7 +248,7 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
 
 #endif /* __KERNEL__ */
 
-#if defined(CONFIG_CFI_CLANG) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
+#if defined(CONFIG_CFI) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
 /*
  * Force a reference to the external symbol so the compiler generates
  * __kcfi_typid.
diff --git a/include/linux/stddef.h b/include/linux/stddef.h
index dab49e2ec8c0..80b6bfb944f0 100644
--- a/include/linux/stddef.h
+++ b/include/linux/stddef.h
@@ -94,7 +94,8 @@ enum {
 	__DECLARE_FLEX_ARRAY(TYPE, NAME)
 
 /**
- * TRAILING_OVERLAP() - Overlap a flexible-array member with trailing members.
+ * __TRAILING_OVERLAP() - Overlap a flexible-array member with trailing
+ *			  members.
  *
  * Creates a union between a flexible-array member (FAM) in a struct and a set
  * of additional members that would otherwise follow it.
@@ -102,15 +103,30 @@ enum {
  * @TYPE: Flexible structure type name, including "struct" keyword.
  * @NAME: Name for a variable to define.
  * @FAM: The flexible-array member within @TYPE
+ * @ATTRS: Any struct attributes (usually empty)
  * @MEMBERS: Trailing overlapping members.
  */
-#define TRAILING_OVERLAP(TYPE, NAME, FAM, MEMBERS)				\
+#define __TRAILING_OVERLAP(TYPE, NAME, FAM, ATTRS, MEMBERS)			\
 	union {									\
 		TYPE NAME;							\
 		struct {							\
-			unsigned char __offset_to_##FAM[offsetof(TYPE, FAM)];	\
+			unsigned char __offset_to_FAM[offsetof(TYPE, FAM)];	\
 			MEMBERS							\
-		};								\
+		} ATTRS;							\
 	}
 
+/**
+ * TRAILING_OVERLAP() - Overlap a flexible-array member with trailing members.
+ *
+ * Creates a union between a flexible-array member (FAM) in a struct and a set
+ * of additional members that would otherwise follow it.
+ *
+ * @TYPE: Flexible structure type name, including "struct" keyword.
+ * @NAME: Name for a variable to define.
+ * @FAM: The flexible-array member within @TYPE
+ * @MEMBERS: Trailing overlapping members.
+ */
+#define TRAILING_OVERLAP(TYPE, NAME, FAM, MEMBERS)				\
+	__TRAILING_OVERLAP(TYPE, NAME, FAM, /* no attrs */, MEMBERS)
+
 #endif
diff --git a/include/linux/string_choices.h b/include/linux/string_choices.h
index f3ba4f52ff26..6c4077be7742 100644
--- a/include/linux/string_choices.h
+++ b/include/linux/string_choices.h
@@ -17,6 +17,12 @@
 
 #include <linux/types.h>
 
+static inline const char *str_assert_deassert(bool v)
+{
+	return v ? "assert" : "deassert";
+}
+#define str_deassert_assert(v)		str_assert_deassert(!(v))
+
 static inline const char *str_enable_disable(bool v)
 {
 	return v ? "enable" : "disable";