diff options
| -rw-r--r-- | Makefile | 4 | ||||
| -rw-r--r-- | common/Kconfig | 2 | ||||
| -rw-r--r-- | lib/Kconfig.ubsan | 35 | ||||
| -rw-r--r-- | lib/Makefile | 3 | ||||
| -rw-r--r-- | lib/ubsan.c | 442 | ||||
| -rw-r--r-- | lib/ubsan.h | 89 | ||||
| -rw-r--r-- | scripts/Makefile.lib | 8 | ||||
| -rw-r--r-- | scripts/Makefile.ubsan | 19 |
8 files changed, 602 insertions, 0 deletions
@@ -329,6 +329,8 @@ export CFLAGS CFLAGS_KERNEL export AFLAGS AFLAGS_KERNEL export LDFLAGS_barebox +export CFLAGS_UBSAN + # Files to ignore in find ... statements RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o -name CVS -o -name .pc -o -name .hg -o -name .git \) -prune -o @@ -489,6 +491,8 @@ CFLAGS += $(call cc-option,-Wno-pointer-sign,) # change __FILE__ to the relative path from the srctree CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=) +include $(srctree)/scripts/Makefile.ubsan + # KBUILD_IMAGE: Default barebox image to build # Depending on the architecture, this can be either compressed or not. # It will also include any necessary headers to be bootable. diff --git a/common/Kconfig b/common/Kconfig index 8aad5baecd..16a2aef7c5 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -1295,6 +1295,8 @@ config PBL_BREAK If this enabled, barebox will be compiled with BKPT instruction on early pbl init. This option should be used only with JTAG debugger! +source "lib/Kconfig.ubsan" + endmenu config HAS_DEBUG_LL diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan new file mode 100644 index 0000000000..09f4a0ab8a --- /dev/null +++ b/lib/Kconfig.ubsan @@ -0,0 +1,35 @@ +# SPDX-License-Identifier: GPL-2.0-only +config ARCH_HAS_UBSAN_SANITIZE_ALL + bool + +config UBSAN + bool "Undefined behaviour sanity checker" + help + This option enables undefined behaviour sanity checker + Compile-time instrumentation is used to detect various undefined + behaviours in runtime. + +config UBSAN_SANITIZE_ALL + bool "Enable instrumentation for all of barebox" + depends on UBSAN + depends on ARCH_HAS_UBSAN_SANITIZE_ALL + default y + help + This option activates instrumentation for all of barebox. + If you don't enable this option, you have to explicitly specify + UBSAN_SANITIZE := y for the files/directories you want to check for UB. + Enabling this option will get barebox image size increased + significantly. + +config UBSAN_NO_ALIGNMENT + bool "Disable checking of pointers alignment" + depends on UBSAN + default y if HAVE_EFFICIENT_UNALIGNED_ACCESS + help + This option disables the check of unaligned memory accesses. + This option should be used when building allmodconfig. + Disabling this option on architectures that support unaligned + accesses may produce a lot of false positives. + +config UBSAN_ALIGNMENT + def_bool !UBSAN_NO_ALIGNMENT diff --git a/lib/Makefile b/lib/Makefile index 161d3a756e..c23937234f 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -71,6 +71,7 @@ obj-$(CONFIG_CRC_CCITT) += crc-ccitt.o obj-$(CONFIG_CRC8) += crc8.o obj-$(CONFIG_NLS) += nls_base.o obj-$(CONFIG_FSL_QE_FIRMWARE) += fsl-qe-firmware.o +obj-$(CONFIG_UBSAN) += ubsan.o # GCC library routines obj-$(CONFIG_GENERIC_LIB_ASHLDI3) += ashldi3.o @@ -79,3 +80,5 @@ obj-$(CONFIG_GENERIC_LIB_LSHRDI3) += lshrdi3.o obj-$(CONFIG_GENERIC_LIB_MULDI3) += muldi3.o pbl-$(CONFIG_GENERIC_LIB_ASHLDI3) += ashldi3.o + +UBSAN_SANITIZE_ubsan.o := n diff --git a/lib/ubsan.c b/lib/ubsan.c new file mode 100644 index 0000000000..89ca6e580b --- /dev/null +++ b/lib/ubsan.c @@ -0,0 +1,442 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * UBSAN error reporting functions + * + * Copyright (c) 2014 Samsung Electronics Co., Ltd. + * Author: Andrey Ryabinin <ryabinin.a.a@gmail.com> + */ + +#include <linux/bitops.h> +#include <linux/bug.h> +#include <linux/ctype.h> +#include <init.h> +#include <linux/kernel.h> +#include <linux/types.h> + +#include "ubsan.h" + +void __ubsan_handle_add_overflow(struct overflow_data *, void *, void *); +void __ubsan_handle_sub_overflow(struct overflow_data *, void *, void *); +void __ubsan_handle_mul_overflow(struct overflow_data *, void *, void *); +void __ubsan_handle_negate_overflow(struct overflow_data *, void *); +void __ubsan_handle_divrem_overflow(struct overflow_data *, void *, void *); +void __ubsan_handle_type_mismatch(struct type_mismatch_data *, void *); +void __ubsan_handle_type_mismatch_v1(struct type_mismatch_data_v1 *, void *); +void __ubsan_handle_out_of_bounds(struct out_of_bounds_data *, void *); +void __ubsan_handle_shift_out_of_bounds(struct shift_out_of_bounds_data *, void *, void *); +void __ubsan_handle_builtin_unreachable(struct unreachable_data *); +void __ubsan_handle_load_invalid_value(struct invalid_value_data *, void *); + +const char *type_check_kinds[] = { + "load of", + "store to", + "reference binding to", + "member access within", + "member call on", + "constructor call on", + "downcast of", + "downcast of" +}; + +#define REPORTED_BIT 31 + +#if (BITS_PER_LONG == 64) && defined(__BIG_ENDIAN) +#define COLUMN_MASK (~(1U << REPORTED_BIT)) +#define LINE_MASK (~0U) +#else +#define COLUMN_MASK (~0U) +#define LINE_MASK (~(1U << REPORTED_BIT)) +#endif + +#define VALUE_LENGTH 40 + +static unsigned int in_ubsan; + +static bool was_reported(struct source_location *location) +{ + return test_and_set_bit(REPORTED_BIT, &location->reported); +} + +static void print_source_location(const char *prefix, + struct source_location *loc) +{ + pr_err("%s %s:%d:%d\n", prefix, loc->file_name, + loc->line & LINE_MASK, loc->column & COLUMN_MASK); +} + +static bool suppress_report(struct source_location *loc) +{ + return in_ubsan || was_reported(loc); +} + +static bool type_is_int(struct type_descriptor *type) +{ + return type->type_kind == type_kind_int; +} + +static bool type_is_signed(struct type_descriptor *type) +{ + WARN_ON(!type_is_int(type)); + return type->type_info & 1; +} + +static unsigned type_bit_width(struct type_descriptor *type) +{ + return 1 << (type->type_info >> 1); +} + +static bool is_inline_int(struct type_descriptor *type) +{ + unsigned inline_bits = sizeof(unsigned long)*8; + unsigned bits = type_bit_width(type); + + WARN_ON(!type_is_int(type)); + + return bits <= inline_bits; +} + +static s_max get_signed_val(struct type_descriptor *type, void *val) +{ + if (is_inline_int(type)) { + unsigned extra_bits = sizeof(s_max)*8 - type_bit_width(type); + unsigned long ulong_val = (unsigned long)val; + + return ((s_max)ulong_val) << extra_bits >> extra_bits; + } + + if (type_bit_width(type) == 64) + return *(s64 *)val; + + return *(s_max *)val; +} + +static bool val_is_negative(struct type_descriptor *type, void *val) +{ + return type_is_signed(type) && get_signed_val(type, val) < 0; +} + +static u_max get_unsigned_val(struct type_descriptor *type, void *val) +{ + if (is_inline_int(type)) + return (unsigned long)val; + + if (type_bit_width(type) == 64) + return *(u64 *)val; + + return *(u_max *)val; +} + +static void val_to_string(char *str, size_t size, struct type_descriptor *type, + void *value) +{ + if (type_is_int(type)) { + if (type_bit_width(type) == 128) { +#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__) + u_max val = get_unsigned_val(type, value); + + scnprintf(str, size, "0x%08x%08x%08x%08x", + (u32)(val >> 96), + (u32)(val >> 64), + (u32)(val >> 32), + (u32)(val)); +#else + WARN_ON(1); +#endif + } else if (type_is_signed(type)) { + scnprintf(str, size, "%lld", + (s64)get_signed_val(type, value)); + } else { + scnprintf(str, size, "%llu", + (u64)get_unsigned_val(type, value)); + } + } +} + +static void ubsan_prologue(struct source_location *location, + unsigned long *flags) +{ + in_ubsan++; + + pr_err("========================================" + "========================================\n"); + print_source_location("UBSAN: Undefined behaviour in", location); +} + +static void ubsan_epilogue(unsigned long *flags) +{ + dump_stack(); + pr_err("========================================" + "========================================\n"); + in_ubsan--; +} + +static void handle_overflow(struct overflow_data *data, void *lhs, + void *rhs, char op) +{ + + struct type_descriptor *type = data->type; + unsigned long flags; + char lhs_val_str[VALUE_LENGTH]; + char rhs_val_str[VALUE_LENGTH]; + + if (suppress_report(&data->location)) + return; + + ubsan_prologue(&data->location, &flags); + + val_to_string(lhs_val_str, sizeof(lhs_val_str), type, lhs); + val_to_string(rhs_val_str, sizeof(rhs_val_str), type, rhs); + pr_err("%s integer overflow:\n", + type_is_signed(type) ? "signed" : "unsigned"); + pr_err("%s %c %s cannot be represented in type %s\n", + lhs_val_str, + op, + rhs_val_str, + type->type_name); + + ubsan_epilogue(&flags); +} + +void __ubsan_handle_add_overflow(struct overflow_data *data, + void *lhs, void *rhs) +{ + + handle_overflow(data, lhs, rhs, '+'); +} +EXPORT_SYMBOL(__ubsan_handle_add_overflow); + +void __ubsan_handle_sub_overflow(struct overflow_data *data, + void *lhs, void *rhs) +{ + handle_overflow(data, lhs, rhs, '-'); +} +EXPORT_SYMBOL(__ubsan_handle_sub_overflow); + +void __ubsan_handle_mul_overflow(struct overflow_data *data, + void *lhs, void *rhs) +{ + handle_overflow(data, lhs, rhs, '*'); +} +EXPORT_SYMBOL(__ubsan_handle_mul_overflow); + +void __ubsan_handle_negate_overflow(struct overflow_data *data, + void *old_val) +{ + unsigned long flags; + char old_val_str[VALUE_LENGTH]; + + if (suppress_report(&data->location)) + return; + + ubsan_prologue(&data->location, &flags); + + val_to_string(old_val_str, sizeof(old_val_str), data->type, old_val); + + pr_err("negation of %s cannot be represented in type %s:\n", + old_val_str, data->type->type_name); + + ubsan_epilogue(&flags); +} +EXPORT_SYMBOL(__ubsan_handle_negate_overflow); + + +void __ubsan_handle_divrem_overflow(struct overflow_data *data, + void *lhs, void *rhs) +{ + unsigned long flags; + char rhs_val_str[VALUE_LENGTH]; + + if (suppress_report(&data->location)) + return; + + ubsan_prologue(&data->location, &flags); + + val_to_string(rhs_val_str, sizeof(rhs_val_str), data->type, rhs); + + if (type_is_signed(data->type) && get_signed_val(data->type, rhs) == -1) + pr_err("division of %s by -1 cannot be represented in type %s\n", + rhs_val_str, data->type->type_name); + else + pr_err("division by zero\n"); + + ubsan_epilogue(&flags); +} +EXPORT_SYMBOL(__ubsan_handle_divrem_overflow); + +static void handle_null_ptr_deref(struct type_mismatch_data_common *data) +{ + unsigned long flags; + + if (suppress_report(data->location)) + return; + + ubsan_prologue(data->location, &flags); + + pr_err("%s null pointer of type %s\n", + type_check_kinds[data->type_check_kind], + data->type->type_name); + + ubsan_epilogue(&flags); +} + +static void handle_misaligned_access(struct type_mismatch_data_common *data, + unsigned long ptr) +{ + unsigned long flags; + + if (suppress_report(data->location)) + return; + + ubsan_prologue(data->location, &flags); + + pr_err("%s misaligned address %p for type %s\n", + type_check_kinds[data->type_check_kind], + (void *)ptr, data->type->type_name); + pr_err("which requires %ld byte alignment\n", data->alignment); + + ubsan_epilogue(&flags); +} + +static void handle_object_size_mismatch(struct type_mismatch_data_common *data, + unsigned long ptr) +{ + unsigned long flags; + + if (suppress_report(data->location)) + return; + + ubsan_prologue(data->location, &flags); + pr_err("%s address %p with insufficient space\n", + type_check_kinds[data->type_check_kind], + (void *) ptr); + pr_err("for an object of type %s\n", data->type->type_name); + ubsan_epilogue(&flags); +} + +static void ubsan_type_mismatch_common(struct type_mismatch_data_common *data, + unsigned long ptr) +{ + if (!ptr) + handle_null_ptr_deref(data); + else if (data->alignment && !IS_ALIGNED(ptr, data->alignment)) + handle_misaligned_access(data, ptr); + else + handle_object_size_mismatch(data, ptr); +} + +void __ubsan_handle_type_mismatch(struct type_mismatch_data *data, + void *ptr) +{ + struct type_mismatch_data_common common_data = { + .location = &data->location, + .type = data->type, + .alignment = data->alignment, + .type_check_kind = data->type_check_kind + }; + + ubsan_type_mismatch_common(&common_data, (unsigned long)ptr); +} +EXPORT_SYMBOL(__ubsan_handle_type_mismatch); + +void __ubsan_handle_type_mismatch_v1(struct type_mismatch_data_v1 *data, + void *ptr) +{ + + struct type_mismatch_data_common common_data = { + .location = &data->location, + .type = data->type, + .alignment = 1UL << data->log_alignment, + .type_check_kind = data->type_check_kind + }; + + ubsan_type_mismatch_common(&common_data, (unsigned long)ptr); +} +EXPORT_SYMBOL(__ubsan_handle_type_mismatch_v1); + +void __ubsan_handle_out_of_bounds(struct out_of_bounds_data *data, void *index) +{ + unsigned long flags; + char index_str[VALUE_LENGTH]; + + if (suppress_report(&data->location)) + return; + + ubsan_prologue(&data->location, &flags); + + val_to_string(index_str, sizeof(index_str), data->index_type, index); + pr_err("index %s is out of range for type %s\n", index_str, + data->array_type->type_name); + ubsan_epilogue(&flags); +} +EXPORT_SYMBOL(__ubsan_handle_out_of_bounds); + +void __ubsan_handle_shift_out_of_bounds(struct shift_out_of_bounds_data *data, + void *lhs, void *rhs) +{ + unsigned long flags; + struct type_descriptor *rhs_type = data->rhs_type; + struct type_descriptor *lhs_type = data->lhs_type; + char rhs_str[VALUE_LENGTH]; + char lhs_str[VALUE_LENGTH]; + + if (suppress_report(&data->location)) + return; + + ubsan_prologue(&data->location, &flags); + + val_to_string(rhs_str, sizeof(rhs_str), rhs_type, rhs); + val_to_string(lhs_str, sizeof(lhs_str), lhs_type, lhs); + + if (val_is_negative(rhs_type, rhs)) + pr_err("shift exponent %s is negative\n", rhs_str); + + else if (get_unsigned_val(rhs_type, rhs) >= + type_bit_width(lhs_type)) + pr_err("shift exponent %s is too large for %u-bit type %s\n", + rhs_str, + type_bit_width(lhs_type), + lhs_type->type_name); + else if (val_is_negative(lhs_type, lhs)) + pr_err("left shift of negative value %s\n", + lhs_str); + else + pr_err("left shift of %s by %s places cannot be" + " represented in type %s\n", + lhs_str, rhs_str, + lhs_type->type_name); + + ubsan_epilogue(&flags); +} +EXPORT_SYMBOL(__ubsan_handle_shift_out_of_bounds); + + +void __ubsan_handle_builtin_unreachable(struct unreachable_data *data) +{ + unsigned long flags; + + ubsan_prologue(&data->location, &flags); + pr_err("calling __builtin_unreachable()\n"); + ubsan_epilogue(&flags); + panic("can't return from __builtin_unreachable()"); +} +EXPORT_SYMBOL(__ubsan_handle_builtin_unreachable); + +void __ubsan_handle_load_invalid_value(struct invalid_value_data *data, + void *val) +{ + unsigned long flags; + char val_str[VALUE_LENGTH]; + + if (suppress_report(&data->location)) + return; + + ubsan_prologue(&data->location, &flags); + + val_to_string(val_str, sizeof(val_str), data->type, val); + + pr_err("load of value %s is not a valid value for type %s\n", + val_str, data->type->type_name); + + ubsan_epilogue(&flags); +} +EXPORT_SYMBOL(__ubsan_handle_load_invalid_value); diff --git a/lib/ubsan.h b/lib/ubsan.h new file mode 100644 index 0000000000..7bbedd4b78 --- /dev/null +++ b/lib/ubsan.h @@ -0,0 +1,89 @@ + /* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LIB_UBSAN_H +#define _LIB_UBSAN_H + +enum { + type_kind_int = 0, + type_kind_float = 1, + type_unknown = 0xffff +}; + +struct type_descriptor { + u16 type_kind; + u16 type_info; + char type_name[1]; +}; + +struct source_location { + const char *file_name; + union { + unsigned long reported; + struct { + u32 line; + u32 column; + }; + }; +}; + +struct overflow_data { + struct source_location location; + struct type_descriptor *type; +}; + +struct type_mismatch_data { + struct source_location location; + struct type_descriptor *type; + unsigned long alignment; + unsigned char type_check_kind; +}; + +struct type_mismatch_data_v1 { + struct source_location location; + struct type_descriptor *type; + unsigned char log_alignment; + unsigned char type_check_kind; +}; + +struct type_mismatch_data_common { + struct source_location *location; + struct type_descriptor *type; + unsigned long alignment; + unsigned char type_check_kind; +}; + +struct nonnull_arg_data { + struct source_location location; + struct source_location attr_location; + int arg_index; +}; + +struct out_of_bounds_data { + struct source_location location; + struct type_descriptor *array_type; + struct type_descriptor *index_type; +}; + +struct shift_out_of_bounds_data { + struct source_location location; + struct type_descriptor *lhs_type; + struct type_descriptor *rhs_type; +}; + +struct unreachable_data { + struct source_location location; +}; + +struct invalid_value_data { + struct source_location location; + struct type_descriptor *type; +}; + +#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__) +typedef __int128 s_max; +typedef unsigned __int128 u_max; +#else +typedef s64 s_max; +typedef u64 u_max; +#endif + +#endif diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index fc5fe3d7e8..c4d307ae30 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -120,6 +120,14 @@ _c_flags = $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$(basetarget).o) _a_flags = $(AFLAGS) $(EXTRA_AFLAGS) $(AFLAGS_$(basetarget).o) _cpp_flags = $(CPPFLAGS) $(EXTRA_CPPFLAGS) $(CPPFLAGS_$(@F)) +ifeq ($(CONFIG_UBSAN),y) +_CFLAGS_UBSAN = $(eval _CFLAGS_UBSAN := $(CFLAGS_UBSAN))$(_CFLAGS_UBSAN) +_c_flags += $(if $(patsubst n%,, \ + $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \ + $(_CFLAGS_UBSAN)) +PBL_CPPFLAGS += $(call cc-option,-fno-sanitize=all) +endif + # If building barebox in a separate objtree expand all occurrences # of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/'). diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan new file mode 100644 index 0000000000..019771b845 --- /dev/null +++ b/scripts/Makefile.ubsan @@ -0,0 +1,19 @@ +# SPDX-License-Identifier: GPL-2.0 +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=signed-integer-overflow) + CFLAGS_UBSAN += $(call cc-option, -fsanitize=bounds) + CFLAGS_UBSAN += $(call cc-option, -fsanitize=object-size) + CFLAGS_UBSAN += $(call cc-option, -fsanitize=bool) + CFLAGS_UBSAN += $(call cc-option, -fsanitize=enum) + +ifdef CONFIG_UBSAN_ALIGNMENT + CFLAGS_UBSAN += $(call cc-option, -fsanitize=alignment) +endif + + # -fsanitize=* options makes GCC less smart than usual and + # increase number of 'maybe-uninitialized false-positives + CFLAGS_UBSAN += $(call cc-option, -Wno-maybe-uninitialized) +endif |