ubsan: add prototypes for internal functions

Most of the functions in ubsan that are only called from generated
code don't have a prototype, which W=1 builds warn about:

lib/ubsan.c:226:6: error: no previous prototype for '__ubsan_handle_divrem_overflow' [-Werror=missing-prototypes]
lib/ubsan.c:307:6: error: no previous prototype for '__ubsan_handle_type_mismatch' [-Werror=missing-prototypes]
lib/ubsan.c:321:6: error: no previous prototype for '__ubsan_handle_type_mismatch_v1' [-Werror=missing-prototypes]
lib/ubsan.c:335:6: error: no previous prototype for '__ubsan_handle_out_of_bounds' [-Werror=missing-prototypes]
lib/ubsan.c:352:6: error: no previous prototype for '__ubsan_handle_shift_out_of_bounds' [-Werror=missing-prototypes]
lib/ubsan.c:394:6: error: no previous prototype for '__ubsan_handle_builtin_unreachable' [-Werror=missing-prototypes]
lib/ubsan.c:404:6: error: no previous prototype for '__ubsan_handle_load_invalid_value' [-Werror=missing-prototypes]

Add prototypes for all of these to lib/ubsan.h, and remove the
one that was already present in ubsan.c.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Fangrui Song <maskray@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230517125102.930491-1-arnd@kernel.org

lib/ubsan.c

@@ -423,9 +423,6 @@ void __ubsan_handle_load_invalid_value(void *_data, void *val)
 }
 EXPORT_SYMBOL(__ubsan_handle_load_invalid_value);
 
-void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr,
-					 unsigned long align,
-					 unsigned long offset);
 void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr,
 					 unsigned long align,
 					 unsigned long offset)

lib/ubsan.h

@@ -124,4 +124,15 @@ typedef s64 s_max;
 typedef u64 u_max;
 #endif
 
+void __ubsan_handle_divrem_overflow(void *_data, void *lhs, void *rhs);
+void __ubsan_handle_type_mismatch(struct type_mismatch_data *data, void *ptr);
+void __ubsan_handle_type_mismatch_v1(void *_data, void *ptr);
+void __ubsan_handle_out_of_bounds(void *_data, void *index);
+void __ubsan_handle_shift_out_of_bounds(void *_data, void *lhs, void *rhs);
+void __ubsan_handle_builtin_unreachable(void *_data);
+void __ubsan_handle_load_invalid_value(void *_data, void *val);
+void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr,
+					 unsigned long align,
+					 unsigned long offset);
+
 #endif