diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Kconfig.debug | 2 | ||||
| -rw-r--r-- | lib/Kconfig.ubsan | 29 | ||||
| -rw-r--r-- | lib/Makefile | 7 | ||||
| -rw-r--r-- | lib/iomap_copy.c | 21 | ||||
| -rw-r--r-- | lib/libcrc32c.c | 1 | ||||
| -rw-r--r-- | lib/string_helpers.c | 63 | ||||
| -rw-r--r-- | lib/test_hexdump.c (renamed from lib/test-hexdump.c) | 146 | ||||
| -rw-r--r-- | lib/ubsan.c | 456 | ||||
| -rw-r--r-- | lib/ubsan.h | 84 |
9 files changed, 743 insertions, 66 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 7d0b49c536c5..ecb9e75614bf 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1893,6 +1893,8 @@ source "samples/Kconfig" source "lib/Kconfig.kgdb" +source "lib/Kconfig.ubsan" + config ARCH_HAS_DEVMEM_IS_ALLOWED bool diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan new file mode 100644 index 000000000000..49518fb48cab --- /dev/null +++ b/lib/Kconfig.ubsan @@ -0,0 +1,29 @@ +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. Various types of checks may be enabled + via boot parameter ubsan_handle (see: Documentation/ubsan.txt). + +config UBSAN_SANITIZE_ALL + bool "Enable instrumentation for the entire kernel" + depends on UBSAN + depends on ARCH_HAS_UBSAN_SANITIZE_ALL + default y + help + This option activates instrumentation for the entire kernel. + 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. + +config UBSAN_ALIGNMENT + bool "Enable checking of pointers alignment" + depends on UBSAN + default y if !HAVE_EFFICIENT_UNALIGNED_ACCESS + help + This option enables detection of unaligned memory accesses. + Enabling this option on architectures that support unalligned + accesses may produce a lot of false positives. diff --git a/lib/Makefile b/lib/Makefile index 180dd4d0dd41..2d4bc33d09b4 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -31,7 +31,7 @@ obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ obj-y += string_helpers.o obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o obj-y += hexdump.o -obj-$(CONFIG_TEST_HEXDUMP) += test-hexdump.o +obj-$(CONFIG_TEST_HEXDUMP) += test_hexdump.o obj-y += kstrtox.o obj-$(CONFIG_TEST_BPF) += test_bpf.o obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o @@ -154,7 +154,7 @@ obj-$(CONFIG_GLOB) += glob.o obj-$(CONFIG_MPILIB) += mpi/ obj-$(CONFIG_SIGNATURE) += digsig.o -obj-$(CONFIG_CLZ_TAB) += clz_tab.o +lib-$(CONFIG_CLZ_TAB) += clz_tab.o obj-$(CONFIG_DDR) += jedec_ddr_data.o @@ -209,3 +209,6 @@ quiet_cmd_build_OID_registry = GEN $@ clean-files += oid_registry_data.c obj-$(CONFIG_UCS2_STRING) += ucs2_string.o +obj-$(CONFIG_UBSAN) += ubsan.o + +UBSAN_SANITIZE_ubsan.o := n diff --git a/lib/iomap_copy.c b/lib/iomap_copy.c index 4527e751b5e0..b8f1d6cbb200 100644 --- a/lib/iomap_copy.c +++ b/lib/iomap_copy.c @@ -42,6 +42,27 @@ void __attribute__((weak)) __iowrite32_copy(void __iomem *to, EXPORT_SYMBOL_GPL(__iowrite32_copy); /** + * __ioread32_copy - copy data from MMIO space, in 32-bit units + * @to: destination (must be 32-bit aligned) + * @from: source, in MMIO space (must be 32-bit aligned) + * @count: number of 32-bit quantities to copy + * + * Copy data from MMIO space to kernel space, in units of 32 bits at a + * time. Order of access is not guaranteed, nor is a memory barrier + * performed afterwards. + */ +void __ioread32_copy(void *to, const void __iomem *from, size_t count) +{ + u32 *dst = to; + const u32 __iomem *src = from; + const u32 __iomem *end = src + count; + + while (src < end) + *dst++ = __raw_readl(src++); +} +EXPORT_SYMBOL_GPL(__ioread32_copy); + +/** * __iowrite64_copy - copy data to MMIO space, in 64-bit or 32-bit units * @to: destination, in MMIO space (must be 64-bit aligned) * @from: source (must be 64-bit aligned) diff --git a/lib/libcrc32c.c b/lib/libcrc32c.c index 6a08ce7d6adc..31ce853fbfb1 100644 --- a/lib/libcrc32c.c +++ b/lib/libcrc32c.c @@ -36,6 +36,7 @@ #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> +#include <linux/crc32c.h> static struct crypto_shash *tfm; diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 5939f63d90cd..5c88204b6f1f 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -43,50 +43,73 @@ void string_get_size(u64 size, u64 blk_size, const enum string_size_units units, [STRING_UNITS_10] = 1000, [STRING_UNITS_2] = 1024, }; - int i, j; - u32 remainder = 0, sf_cap, exp; + static const unsigned int rounding[] = { 500, 50, 5 }; + int i = 0, j; + u32 remainder = 0, sf_cap; char tmp[8]; const char *unit; tmp[0] = '\0'; - i = 0; - if (!size) + + if (blk_size == 0) + size = 0; + if (size == 0) goto out; - while (blk_size >= divisor[units]) { - remainder = do_div(blk_size, divisor[units]); + /* This is Napier's algorithm. Reduce the original block size to + * + * coefficient * divisor[units]^i + * + * we do the reduction so both coefficients are just under 32 bits so + * that multiplying them together won't overflow 64 bits and we keep + * as much precision as possible in the numbers. + * + * Note: it's safe to throw away the remainders here because all the + * precision is in the coefficients. + */ + while (blk_size >> 32) { + do_div(blk_size, divisor[units]); i++; } - exp = divisor[units] / (u32)blk_size; - /* - * size must be strictly greater than exp here to ensure that remainder - * is greater than divisor[units] coming out of the if below. - */ - if (size > exp) { - remainder = do_div(size, divisor[units]); - remainder *= blk_size; + while (size >> 32) { + do_div(size, divisor[units]); i++; - } else { - remainder *= size; } + /* now perform the actual multiplication keeping i as the sum of the + * two logarithms */ size *= blk_size; - size += remainder / divisor[units]; - remainder %= divisor[units]; + /* and logarithmically reduce it until it's just under the divisor */ while (size >= divisor[units]) { remainder = do_div(size, divisor[units]); i++; } + /* work out in j how many digits of precision we need from the + * remainder */ sf_cap = size; for (j = 0; sf_cap*10 < 1000; j++) sf_cap *= 10; - if (j) { + if (units == STRING_UNITS_2) { + /* express the remainder as a decimal. It's currently the + * numerator of a fraction whose denominator is + * divisor[units], which is 1 << 10 for STRING_UNITS_2 */ remainder *= 1000; - remainder /= divisor[units]; + remainder >>= 10; + } + + /* add a 5 to the digit below what will be printed to ensure + * an arithmetical round up and carry it through to size */ + remainder += rounding[j]; + if (remainder >= 1000) { + remainder -= 1000; + size += 1; + } + + if (j) { snprintf(tmp, sizeof(tmp), ".%03u", remainder); tmp[j+1] = '\0'; } diff --git a/lib/test-hexdump.c b/lib/test_hexdump.c index 5241df36eedf..3f415d8101f3 100644 --- a/lib/test-hexdump.c +++ b/lib/test_hexdump.c @@ -42,19 +42,21 @@ static const char * const test_data_8_le[] __initconst = { "e9ac0f9cad319ca6", "0cafb1439919d14c", }; -static void __init test_hexdump(size_t len, int rowsize, int groupsize, - bool ascii) +#define FILL_CHAR '#' + +static unsigned total_tests __initdata; +static unsigned failed_tests __initdata; + +static void __init test_hexdump_prepare_test(size_t len, int rowsize, + int groupsize, char *test, + size_t testlen, bool ascii) { - char test[32 * 3 + 2 + 32 + 1]; - char real[32 * 3 + 2 + 32 + 1]; char *p; const char * const *result; size_t l = len; int gs = groupsize, rs = rowsize; unsigned int i; - hex_dump_to_buffer(data_b, l, rs, gs, real, sizeof(real), ascii); - if (rs != 16 && rs != 32) rs = 16; @@ -73,8 +75,6 @@ static void __init test_hexdump(size_t len, int rowsize, int groupsize, else result = test_data_1_le; - memset(test, ' ', sizeof(test)); - /* hex dump */ p = test; for (i = 0; i < l / gs; i++) { @@ -82,24 +82,49 @@ static void __init test_hexdump(size_t len, int rowsize, int groupsize, size_t amount = strlen(q); strncpy(p, q, amount); - p += amount + 1; + p += amount; + + *p++ = ' '; } if (i) p--; /* ASCII part */ if (ascii) { - p = test + rs * 2 + rs / gs + 1; + do { + *p++ = ' '; + } while (p < test + rs * 2 + rs / gs + 1); + strncpy(p, data_a, l); p += l; } *p = '\0'; +} - if (strcmp(test, real)) { +#define TEST_HEXDUMP_BUF_SIZE (32 * 3 + 2 + 32 + 1) + +static void __init test_hexdump(size_t len, int rowsize, int groupsize, + bool ascii) +{ + char test[TEST_HEXDUMP_BUF_SIZE]; + char real[TEST_HEXDUMP_BUF_SIZE]; + + total_tests++; + + memset(real, FILL_CHAR, sizeof(real)); + hex_dump_to_buffer(data_b, len, rowsize, groupsize, real, sizeof(real), + ascii); + + memset(test, FILL_CHAR, sizeof(test)); + test_hexdump_prepare_test(len, rowsize, groupsize, test, sizeof(test), + ascii); + + if (memcmp(test, real, TEST_HEXDUMP_BUF_SIZE)) { pr_err("Len: %zu row: %d group: %d\n", len, rowsize, groupsize); pr_err("Result: '%s'\n", real); pr_err("Expect: '%s'\n", test); + failed_tests++; } } @@ -114,52 +139,72 @@ static void __init test_hexdump_set(int rowsize, bool ascii) test_hexdump(len, rowsize, 1, ascii); } -static void __init test_hexdump_overflow(bool ascii) +static void __init test_hexdump_overflow(size_t buflen, size_t len, + int rowsize, int groupsize, + bool ascii) { - char buf[56]; - const char *t = test_data_1_le[0]; - size_t l = get_random_int() % sizeof(buf); + char test[TEST_HEXDUMP_BUF_SIZE]; + char buf[TEST_HEXDUMP_BUF_SIZE]; + int rs = rowsize, gs = groupsize; + int ae, he, e, f, r; bool a; - int e, r; - memset(buf, ' ', sizeof(buf)); + total_tests++; + + memset(buf, FILL_CHAR, sizeof(buf)); - r = hex_dump_to_buffer(data_b, 1, 16, 1, buf, l, ascii); + r = hex_dump_to_buffer(data_b, len, rs, gs, buf, buflen, ascii); + + /* + * Caller must provide the data length multiple of groupsize. The + * calculations below are made with that assumption in mind. + */ + ae = rs * 2 /* hex */ + rs / gs /* spaces */ + 1 /* space */ + len /* ascii */; + he = (gs * 2 /* hex */ + 1 /* space */) * len / gs - 1 /* no trailing space */; if (ascii) - e = 50; + e = ae; else - e = 2; - buf[e + 2] = '\0'; - - if (!l) { - a = r == e && buf[0] == ' '; - } else if (l < 3) { - a = r == e && buf[0] == '\0'; - } else if (l < 4) { - a = r == e && !strcmp(buf, t); - } else if (ascii) { - if (l < 51) - a = r == e && buf[l - 1] == '\0' && buf[l - 2] == ' '; - else - a = r == e && buf[50] == '\0' && buf[49] == '.'; - } else { - a = r == e && buf[e] == '\0'; + e = he; + + f = min_t(int, e + 1, buflen); + if (buflen) { + test_hexdump_prepare_test(len, rs, gs, test, sizeof(test), ascii); + test[f - 1] = '\0'; } + memset(test + f, FILL_CHAR, sizeof(test) - f); + + a = r == e && !memcmp(test, buf, TEST_HEXDUMP_BUF_SIZE); + + buf[sizeof(buf) - 1] = '\0'; if (!a) { - pr_err("Len: %zu rc: %u strlen: %zu\n", l, r, strlen(buf)); - pr_err("Result: '%s'\n", buf); + pr_err("Len: %zu buflen: %zu strlen: %zu\n", + len, buflen, strnlen(buf, sizeof(buf))); + pr_err("Result: %d '%s'\n", r, buf); + pr_err("Expect: %d '%s'\n", e, test); + failed_tests++; } } +static void __init test_hexdump_overflow_set(size_t buflen, bool ascii) +{ + unsigned int i = 0; + int rs = (get_random_int() % 2 + 1) * 16; + + do { + int gs = 1 << i; + size_t len = get_random_int() % rs + gs; + + test_hexdump_overflow(buflen, rounddown(len, gs), rs, gs, ascii); + } while (i++ < 3); +} + static int __init test_hexdump_init(void) { unsigned int i; int rowsize; - pr_info("Running tests...\n"); - rowsize = (get_random_int() % 2 + 1) * 16; for (i = 0; i < 16; i++) test_hexdump_set(rowsize, false); @@ -168,13 +213,26 @@ static int __init test_hexdump_init(void) for (i = 0; i < 16; i++) test_hexdump_set(rowsize, true); - for (i = 0; i < 16; i++) - test_hexdump_overflow(false); + for (i = 0; i <= TEST_HEXDUMP_BUF_SIZE; i++) + test_hexdump_overflow_set(i, false); - for (i = 0; i < 16; i++) - test_hexdump_overflow(true); + for (i = 0; i <= TEST_HEXDUMP_BUF_SIZE; i++) + test_hexdump_overflow_set(i, true); + + if (failed_tests == 0) + pr_info("all %u tests passed\n", total_tests); + else + pr_err("failed %u out of %u tests\n", failed_tests, total_tests); - return -EINVAL; + return failed_tests ? -EINVAL : 0; } module_init(test_hexdump_init); + +static void __exit test_hexdump_exit(void) +{ + /* do nothing */ +} +module_exit(test_hexdump_exit); + +MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>"); MODULE_LICENSE("Dual BSD/GPL"); diff --git a/lib/ubsan.c b/lib/ubsan.c new file mode 100644 index 000000000000..8799ae5e2e42 --- /dev/null +++ b/lib/ubsan.c @@ -0,0 +1,456 @@ +/* + * UBSAN error reporting functions + * + * Copyright (c) 2014 Samsung Electronics Co., Ltd. + * Author: Andrey Ryabinin <ryabinin.a.a@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/bitops.h> +#include <linux/bug.h> +#include <linux/ctype.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/sched.h> + +#include "ubsan.h" + +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 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 current->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, unsigned long val) +{ + if (is_inline_int(type)) { + unsigned extra_bits = sizeof(s_max)*8 - type_bit_width(type); + return ((s_max)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, unsigned long val) +{ + return type_is_signed(type) && get_signed_val(type, val) < 0; +} + +static u_max get_unsigned_val(struct type_descriptor *type, unsigned long val) +{ + if (is_inline_int(type)) + return 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, + unsigned long 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 bool location_is_valid(struct source_location *loc) +{ + return loc->file_name != NULL; +} + +static DEFINE_SPINLOCK(report_lock); + +static void ubsan_prologue(struct source_location *location, + unsigned long *flags) +{ + current->in_ubsan++; + spin_lock_irqsave(&report_lock, *flags); + + pr_err("========================================" + "========================================\n"); + print_source_location("UBSAN: Undefined behaviour in", location); +} + +static void ubsan_epilogue(unsigned long *flags) +{ + dump_stack(); + pr_err("========================================" + "========================================\n"); + spin_unlock_irqrestore(&report_lock, *flags); + current->in_ubsan--; +} + +static void handle_overflow(struct overflow_data *data, unsigned long lhs, + unsigned long 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, + unsigned long lhs, + unsigned long rhs) +{ + + handle_overflow(data, lhs, rhs, '+'); +} +EXPORT_SYMBOL(__ubsan_handle_add_overflow); + +void __ubsan_handle_sub_overflow(struct overflow_data *data, + unsigned long lhs, + unsigned long rhs) +{ + handle_overflow(data, lhs, rhs, '-'); +} +EXPORT_SYMBOL(__ubsan_handle_sub_overflow); + +void __ubsan_handle_mul_overflow(struct overflow_data *data, + unsigned long lhs, + unsigned long rhs) +{ + handle_overflow(data, lhs, rhs, '*'); +} +EXPORT_SYMBOL(__ubsan_handle_mul_overflow); + +void __ubsan_handle_negate_overflow(struct overflow_data *data, + unsigned long 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, + unsigned long lhs, + unsigned long 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 *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_missaligned_access(struct type_mismatch_data *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 *data, + unsigned long ptr) +{ + unsigned long flags; + + if (suppress_report(&data->location)) + return; + + ubsan_prologue(&data->location, &flags); + pr_err("%s address %pk 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); +} + +void __ubsan_handle_type_mismatch(struct type_mismatch_data *data, + unsigned long ptr) +{ + + if (!ptr) + handle_null_ptr_deref(data); + else if (data->alignment && !IS_ALIGNED(ptr, data->alignment)) + handle_missaligned_access(data, ptr); + else + handle_object_size_mismatch(data, ptr); +} +EXPORT_SYMBOL(__ubsan_handle_type_mismatch); + +void __ubsan_handle_nonnull_return(struct nonnull_return_data *data) +{ + unsigned long flags; + + if (suppress_report(&data->location)) + return; + + ubsan_prologue(&data->location, &flags); + + pr_err("null pointer returned from function declared to never return null\n"); + + if (location_is_valid(&data->attr_location)) + print_source_location("returns_nonnull attribute specified in", + &data->attr_location); + + ubsan_epilogue(&flags); +} +EXPORT_SYMBOL(__ubsan_handle_nonnull_return); + +void __ubsan_handle_vla_bound_not_positive(struct vla_bound_data *data, + unsigned long 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, + unsigned long 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, + unsigned long lhs, unsigned long 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 __noreturn +__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, + unsigned long 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 000000000000..b2d18d4a53f5 --- /dev/null +++ b/lib/ubsan.h @@ -0,0 +1,84 @@ +#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 nonnull_arg_data { + struct source_location location; + struct source_location attr_location; + int arg_index; +}; + +struct nonnull_return_data { + struct source_location location; + struct source_location attr_location; +}; + +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; + 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 |