[PATCH 2/2] ubsan: Remove vla bound checks.

From: Andrey Ryabinin
Date: Mon May 06 2019 - 06:45:50 EST


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@xxxxxxxxxxxxx>
---
lib/ubsan.c | 18 ------------------
lib/ubsan.h | 5 -----
scripts/Makefile.ubsan | 1 -
3 files changed, 24 deletions(-)

diff --git a/lib/ubsan.c b/lib/ubsan.c
index 1e9e2ab25539..c4859c2d2f1b 100644
--- a/lib/ubsan.c
+++ b/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;
diff --git a/lib/ubsan.h b/lib/ubsan.h
index f4d8d0bd4016..b8fa83864467 100644
--- a/lib/ubsan.h
+++ b/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;
diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan
index 38b2b4818e8e..019771b845c5 100644
--- a/scripts/Makefile.ubsan
+++ b/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)
--
2.21.0