ubsan: Remove vla bound checks.

The kernel the kernel is built with -Wvla for some time, so is not
supposed to have any variable length arrays.  Remove vla bounds checking
from ubsan since it's useless now.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/ubsan.c

@@ -349,24 +349,6 @@ void __ubsan_handle_type_mismatch_v1(struct type_mismatch_data_v1 *data,
 }
 EXPORT_SYMBOL(__ubsan_handle_type_mismatch_v1);
 
-void __ubsan_handle_vla_bound_not_positive(struct vla_bound_data *data,
-					void *bound)
-{
-	unsigned long flags;
-	char bound_str[VALUE_LENGTH];
-
-	if (suppress_report(&data->location))
-		return;
-
-	ubsan_prologue(&data->location, &flags);
-
-	val_to_string(bound_str, sizeof(bound_str), data->type, bound);
-	pr_err("variable length array bound value %s <= 0\n", bound_str);
-
-	ubsan_epilogue(&flags);
-}
-EXPORT_SYMBOL(__ubsan_handle_vla_bound_not_positive);
-
 void __ubsan_handle_out_of_bounds(struct out_of_bounds_data *data, void *index)
 {
 	unsigned long flags;

lib/ubsan.h

@@ -57,11 +57,6 @@ struct nonnull_arg_data {
 	int arg_index;
 };
 
-struct vla_bound_data {
-	struct source_location location;
-	struct type_descriptor *type;
-};
-
 struct out_of_bounds_data {
 	struct source_location location;
 	struct type_descriptor *array_type;

scripts/Makefile.ubsan

@@ -3,7 +3,6 @@ ifdef CONFIG_UBSAN
       CFLAGS_UBSAN += $(call cc-option, -fsanitize=shift)
       CFLAGS_UBSAN += $(call cc-option, -fsanitize=integer-divide-by-zero)
       CFLAGS_UBSAN += $(call cc-option, -fsanitize=unreachable)
-      CFLAGS_UBSAN += $(call cc-option, -fsanitize=vla-bound)
       CFLAGS_UBSAN += $(call cc-option, -fsanitize=signed-integer-overflow)
       CFLAGS_UBSAN += $(call cc-option, -fsanitize=bounds)
       CFLAGS_UBSAN += $(call cc-option, -fsanitize=object-size)