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Diffstat (limited to '')
| -rw-r--r-- | lib/test_overflow.c | 712 |
1 files changed, 712 insertions, 0 deletions
diff --git a/lib/test_overflow.c b/lib/test_overflow.c new file mode 100644 index 000000000..7a5a5738d --- /dev/null +++ b/lib/test_overflow.c @@ -0,0 +1,712 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT +/* + * Test cases for arithmetic overflow checks. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/device.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/overflow.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/vmalloc.h> + +#define DEFINE_TEST_ARRAY(t) \ + static const struct test_ ## t { \ + t a, b; \ + t sum, diff, prod; \ + bool s_of, d_of, p_of; \ + } t ## _tests[] __initconst + +DEFINE_TEST_ARRAY(u8) = { + {0, 0, 0, 0, 0, false, false, false}, + {1, 1, 2, 0, 1, false, false, false}, + {0, 1, 1, U8_MAX, 0, false, true, false}, + {1, 0, 1, 1, 0, false, false, false}, + {0, U8_MAX, U8_MAX, 1, 0, false, true, false}, + {U8_MAX, 0, U8_MAX, U8_MAX, 0, false, false, false}, + {1, U8_MAX, 0, 2, U8_MAX, true, true, false}, + {U8_MAX, 1, 0, U8_MAX-1, U8_MAX, true, false, false}, + {U8_MAX, U8_MAX, U8_MAX-1, 0, 1, true, false, true}, + + {U8_MAX, U8_MAX-1, U8_MAX-2, 1, 2, true, false, true}, + {U8_MAX-1, U8_MAX, U8_MAX-2, U8_MAX, 2, true, true, true}, + + {1U << 3, 1U << 3, 1U << 4, 0, 1U << 6, false, false, false}, + {1U << 4, 1U << 4, 1U << 5, 0, 0, false, false, true}, + {1U << 4, 1U << 3, 3*(1U << 3), 1U << 3, 1U << 7, false, false, false}, + {1U << 7, 1U << 7, 0, 0, 0, true, false, true}, + + {48, 32, 80, 16, 0, false, false, true}, + {128, 128, 0, 0, 0, true, false, true}, + {123, 234, 101, 145, 110, true, true, true}, +}; +DEFINE_TEST_ARRAY(u16) = { + {0, 0, 0, 0, 0, false, false, false}, + {1, 1, 2, 0, 1, false, false, false}, + {0, 1, 1, U16_MAX, 0, false, true, false}, + {1, 0, 1, 1, 0, false, false, false}, + {0, U16_MAX, U16_MAX, 1, 0, false, true, false}, + {U16_MAX, 0, U16_MAX, U16_MAX, 0, false, false, false}, + {1, U16_MAX, 0, 2, U16_MAX, true, true, false}, + {U16_MAX, 1, 0, U16_MAX-1, U16_MAX, true, false, false}, + {U16_MAX, U16_MAX, U16_MAX-1, 0, 1, true, false, true}, + + {U16_MAX, U16_MAX-1, U16_MAX-2, 1, 2, true, false, true}, + {U16_MAX-1, U16_MAX, U16_MAX-2, U16_MAX, 2, true, true, true}, + + {1U << 7, 1U << 7, 1U << 8, 0, 1U << 14, false, false, false}, + {1U << 8, 1U << 8, 1U << 9, 0, 0, false, false, true}, + {1U << 8, 1U << 7, 3*(1U << 7), 1U << 7, 1U << 15, false, false, false}, + {1U << 15, 1U << 15, 0, 0, 0, true, false, true}, + + {123, 234, 357, 65425, 28782, false, true, false}, + {1234, 2345, 3579, 64425, 10146, false, true, true}, +}; +DEFINE_TEST_ARRAY(u32) = { + {0, 0, 0, 0, 0, false, false, false}, + {1, 1, 2, 0, 1, false, false, false}, + {0, 1, 1, U32_MAX, 0, false, true, false}, + {1, 0, 1, 1, 0, false, false, false}, + {0, U32_MAX, U32_MAX, 1, 0, false, true, false}, + {U32_MAX, 0, U32_MAX, U32_MAX, 0, false, false, false}, + {1, U32_MAX, 0, 2, U32_MAX, true, true, false}, + {U32_MAX, 1, 0, U32_MAX-1, U32_MAX, true, false, false}, + {U32_MAX, U32_MAX, U32_MAX-1, 0, 1, true, false, true}, + + {U32_MAX, U32_MAX-1, U32_MAX-2, 1, 2, true, false, true}, + {U32_MAX-1, U32_MAX, U32_MAX-2, U32_MAX, 2, true, true, true}, + + {1U << 15, 1U << 15, 1U << 16, 0, 1U << 30, false, false, false}, + {1U << 16, 1U << 16, 1U << 17, 0, 0, false, false, true}, + {1U << 16, 1U << 15, 3*(1U << 15), 1U << 15, 1U << 31, false, false, false}, + {1U << 31, 1U << 31, 0, 0, 0, true, false, true}, + + {-2U, 1U, -1U, -3U, -2U, false, false, false}, + {-4U, 5U, 1U, -9U, -20U, true, false, true}, +}; + +DEFINE_TEST_ARRAY(u64) = { + {0, 0, 0, 0, 0, false, false, false}, + {1, 1, 2, 0, 1, false, false, false}, + {0, 1, 1, U64_MAX, 0, false, true, false}, + {1, 0, 1, 1, 0, false, false, false}, + {0, U64_MAX, U64_MAX, 1, 0, false, true, false}, + {U64_MAX, 0, U64_MAX, U64_MAX, 0, false, false, false}, + {1, U64_MAX, 0, 2, U64_MAX, true, true, false}, + {U64_MAX, 1, 0, U64_MAX-1, U64_MAX, true, false, false}, + {U64_MAX, U64_MAX, U64_MAX-1, 0, 1, true, false, true}, + + {U64_MAX, U64_MAX-1, U64_MAX-2, 1, 2, true, false, true}, + {U64_MAX-1, U64_MAX, U64_MAX-2, U64_MAX, 2, true, true, true}, + + {1ULL << 31, 1ULL << 31, 1ULL << 32, 0, 1ULL << 62, false, false, false}, + {1ULL << 32, 1ULL << 32, 1ULL << 33, 0, 0, false, false, true}, + {1ULL << 32, 1ULL << 31, 3*(1ULL << 31), 1ULL << 31, 1ULL << 63, false, false, false}, + {1ULL << 63, 1ULL << 63, 0, 0, 0, true, false, true}, + {1000000000ULL /* 10^9 */, 10000000000ULL /* 10^10 */, + 11000000000ULL, 18446744064709551616ULL, 10000000000000000000ULL, + false, true, false}, + {-15ULL, 10ULL, -5ULL, -25ULL, -150ULL, false, false, true}, +}; + +DEFINE_TEST_ARRAY(s8) = { + {0, 0, 0, 0, 0, false, false, false}, + + {0, S8_MAX, S8_MAX, -S8_MAX, 0, false, false, false}, + {S8_MAX, 0, S8_MAX, S8_MAX, 0, false, false, false}, + {0, S8_MIN, S8_MIN, S8_MIN, 0, false, true, false}, + {S8_MIN, 0, S8_MIN, S8_MIN, 0, false, false, false}, + + {-1, S8_MIN, S8_MAX, S8_MAX, S8_MIN, true, false, true}, + {S8_MIN, -1, S8_MAX, -S8_MAX, S8_MIN, true, false, true}, + {-1, S8_MAX, S8_MAX-1, S8_MIN, -S8_MAX, false, false, false}, + {S8_MAX, -1, S8_MAX-1, S8_MIN, -S8_MAX, false, true, false}, + {-1, -S8_MAX, S8_MIN, S8_MAX-1, S8_MAX, false, false, false}, + {-S8_MAX, -1, S8_MIN, S8_MIN+2, S8_MAX, false, false, false}, + + {1, S8_MIN, -S8_MAX, -S8_MAX, S8_MIN, false, true, false}, + {S8_MIN, 1, -S8_MAX, S8_MAX, S8_MIN, false, true, false}, + {1, S8_MAX, S8_MIN, S8_MIN+2, S8_MAX, true, false, false}, + {S8_MAX, 1, S8_MIN, S8_MAX-1, S8_MAX, true, false, false}, + + {S8_MIN, S8_MIN, 0, 0, 0, true, false, true}, + {S8_MAX, S8_MAX, -2, 0, 1, true, false, true}, + + {-4, -32, -36, 28, -128, false, false, true}, + {-4, 32, 28, -36, -128, false, false, false}, +}; + +DEFINE_TEST_ARRAY(s16) = { + {0, 0, 0, 0, 0, false, false, false}, + + {0, S16_MAX, S16_MAX, -S16_MAX, 0, false, false, false}, + {S16_MAX, 0, S16_MAX, S16_MAX, 0, false, false, false}, + {0, S16_MIN, S16_MIN, S16_MIN, 0, false, true, false}, + {S16_MIN, 0, S16_MIN, S16_MIN, 0, false, false, false}, + + {-1, S16_MIN, S16_MAX, S16_MAX, S16_MIN, true, false, true}, + {S16_MIN, -1, S16_MAX, -S16_MAX, S16_MIN, true, false, true}, + {-1, S16_MAX, S16_MAX-1, S16_MIN, -S16_MAX, false, false, false}, + {S16_MAX, -1, S16_MAX-1, S16_MIN, -S16_MAX, false, true, false}, + {-1, -S16_MAX, S16_MIN, S16_MAX-1, S16_MAX, false, false, false}, + {-S16_MAX, -1, S16_MIN, S16_MIN+2, S16_MAX, false, false, false}, + + {1, S16_MIN, -S16_MAX, -S16_MAX, S16_MIN, false, true, false}, + {S16_MIN, 1, -S16_MAX, S16_MAX, S16_MIN, false, true, false}, + {1, S16_MAX, S16_MIN, S16_MIN+2, S16_MAX, true, false, false}, + {S16_MAX, 1, S16_MIN, S16_MAX-1, S16_MAX, true, false, false}, + + {S16_MIN, S16_MIN, 0, 0, 0, true, false, true}, + {S16_MAX, S16_MAX, -2, 0, 1, true, false, true}, +}; +DEFINE_TEST_ARRAY(s32) = { + {0, 0, 0, 0, 0, false, false, false}, + + {0, S32_MAX, S32_MAX, -S32_MAX, 0, false, false, false}, + {S32_MAX, 0, S32_MAX, S32_MAX, 0, false, false, false}, + {0, S32_MIN, S32_MIN, S32_MIN, 0, false, true, false}, + {S32_MIN, 0, S32_MIN, S32_MIN, 0, false, false, false}, + + {-1, S32_MIN, S32_MAX, S32_MAX, S32_MIN, true, false, true}, + {S32_MIN, -1, S32_MAX, -S32_MAX, S32_MIN, true, false, true}, + {-1, S32_MAX, S32_MAX-1, S32_MIN, -S32_MAX, false, false, false}, + {S32_MAX, -1, S32_MAX-1, S32_MIN, -S32_MAX, false, true, false}, + {-1, -S32_MAX, S32_MIN, S32_MAX-1, S32_MAX, false, false, false}, + {-S32_MAX, -1, S32_MIN, S32_MIN+2, S32_MAX, false, false, false}, + + {1, S32_MIN, -S32_MAX, -S32_MAX, S32_MIN, false, true, false}, + {S32_MIN, 1, -S32_MAX, S32_MAX, S32_MIN, false, true, false}, + {1, S32_MAX, S32_MIN, S32_MIN+2, S32_MAX, true, false, false}, + {S32_MAX, 1, S32_MIN, S32_MAX-1, S32_MAX, true, false, false}, + + {S32_MIN, S32_MIN, 0, 0, 0, true, false, true}, + {S32_MAX, S32_MAX, -2, 0, 1, true, false, true}, +}; +DEFINE_TEST_ARRAY(s64) = { + {0, 0, 0, 0, 0, false, false, false}, + + {0, S64_MAX, S64_MAX, -S64_MAX, 0, false, false, false}, + {S64_MAX, 0, S64_MAX, S64_MAX, 0, false, false, false}, + {0, S64_MIN, S64_MIN, S64_MIN, 0, false, true, false}, + {S64_MIN, 0, S64_MIN, S64_MIN, 0, false, false, false}, + + {-1, S64_MIN, S64_MAX, S64_MAX, S64_MIN, true, false, true}, + {S64_MIN, -1, S64_MAX, -S64_MAX, S64_MIN, true, false, true}, + {-1, S64_MAX, S64_MAX-1, S64_MIN, -S64_MAX, false, false, false}, + {S64_MAX, -1, S64_MAX-1, S64_MIN, -S64_MAX, false, true, false}, + {-1, -S64_MAX, S64_MIN, S64_MAX-1, S64_MAX, false, false, false}, + {-S64_MAX, -1, S64_MIN, S64_MIN+2, S64_MAX, false, false, false}, + + {1, S64_MIN, -S64_MAX, -S64_MAX, S64_MIN, false, true, false}, + {S64_MIN, 1, -S64_MAX, S64_MAX, S64_MIN, false, true, false}, + {1, S64_MAX, S64_MIN, S64_MIN+2, S64_MAX, true, false, false}, + {S64_MAX, 1, S64_MIN, S64_MAX-1, S64_MAX, true, false, false}, + + {S64_MIN, S64_MIN, 0, 0, 0, true, false, true}, + {S64_MAX, S64_MAX, -2, 0, 1, true, false, true}, + + {-1, -1, -2, 0, 1, false, false, false}, + {-1, -128, -129, 127, 128, false, false, false}, + {-128, -1, -129, -127, 128, false, false, false}, + {0, -S64_MAX, -S64_MAX, S64_MAX, 0, false, false, false}, +}; + +#define check_one_op(t, fmt, op, sym, a, b, r, of) do { \ + t _r; \ + bool _of; \ + \ + _of = check_ ## op ## _overflow(a, b, &_r); \ + if (_of != of) { \ + pr_warn("expected "fmt" "sym" "fmt \ + " to%s overflow (type %s)\n", \ + a, b, of ? "" : " not", #t); \ + err = 1; \ + } \ + if (_r != r) { \ + pr_warn("expected "fmt" "sym" "fmt" == " \ + fmt", got "fmt" (type %s)\n", \ + a, b, r, _r, #t); \ + err = 1; \ + } \ +} while (0) + +#define DEFINE_TEST_FUNC(t, fmt) \ +static int __init do_test_ ## t(const struct test_ ## t *p) \ +{ \ + int err = 0; \ + \ + check_one_op(t, fmt, add, "+", p->a, p->b, p->sum, p->s_of); \ + check_one_op(t, fmt, add, "+", p->b, p->a, p->sum, p->s_of); \ + check_one_op(t, fmt, sub, "-", p->a, p->b, p->diff, p->d_of); \ + check_one_op(t, fmt, mul, "*", p->a, p->b, p->prod, p->p_of); \ + check_one_op(t, fmt, mul, "*", p->b, p->a, p->prod, p->p_of); \ + \ + return err; \ +} \ + \ +static int __init test_ ## t ## _overflow(void) { \ + int err = 0; \ + unsigned i; \ + \ + pr_info("%-3s: %zu arithmetic tests\n", #t, \ + ARRAY_SIZE(t ## _tests)); \ + for (i = 0; i < ARRAY_SIZE(t ## _tests); ++i) \ + err |= do_test_ ## t(&t ## _tests[i]); \ + return err; \ +} + +DEFINE_TEST_FUNC(u8, "%d"); +DEFINE_TEST_FUNC(s8, "%d"); +DEFINE_TEST_FUNC(u16, "%d"); +DEFINE_TEST_FUNC(s16, "%d"); +DEFINE_TEST_FUNC(u32, "%u"); +DEFINE_TEST_FUNC(s32, "%d"); +#if BITS_PER_LONG == 64 +DEFINE_TEST_FUNC(u64, "%llu"); +DEFINE_TEST_FUNC(s64, "%lld"); +#endif + +static int __init test_overflow_calculation(void) +{ + int err = 0; + + err |= test_u8_overflow(); + err |= test_s8_overflow(); + err |= test_u16_overflow(); + err |= test_s16_overflow(); + err |= test_u32_overflow(); + err |= test_s32_overflow(); +#if BITS_PER_LONG == 64 + err |= test_u64_overflow(); + err |= test_s64_overflow(); +#endif + + return err; +} + +static int __init test_overflow_shift(void) +{ + int err = 0; + +/* Args are: value, shift, type, expected result, overflow expected */ +#define TEST_ONE_SHIFT(a, s, t, expect, of) ({ \ + int __failed = 0; \ + typeof(a) __a = (a); \ + typeof(s) __s = (s); \ + t __e = (expect); \ + t __d; \ + bool __of = check_shl_overflow(__a, __s, &__d); \ + if (__of != of) { \ + pr_warn("expected (%s)(%s << %s) to%s overflow\n", \ + #t, #a, #s, of ? "" : " not"); \ + __failed = 1; \ + } else if (!__of && __d != __e) { \ + pr_warn("expected (%s)(%s << %s) == %s\n", \ + #t, #a, #s, #expect); \ + if ((t)-1 < 0) \ + pr_warn("got %lld\n", (s64)__d); \ + else \ + pr_warn("got %llu\n", (u64)__d); \ + __failed = 1; \ + } \ + if (!__failed) \ + pr_info("ok: (%s)(%s << %s) == %s\n", #t, #a, #s, \ + of ? "overflow" : #expect); \ + __failed; \ +}) + + /* Sane shifts. */ + err |= TEST_ONE_SHIFT(1, 0, u8, 1 << 0, false); + err |= TEST_ONE_SHIFT(1, 4, u8, 1 << 4, false); + err |= TEST_ONE_SHIFT(1, 7, u8, 1 << 7, false); + err |= TEST_ONE_SHIFT(0xF, 4, u8, 0xF << 4, false); + err |= TEST_ONE_SHIFT(1, 0, u16, 1 << 0, false); + err |= TEST_ONE_SHIFT(1, 10, u16, 1 << 10, false); + err |= TEST_ONE_SHIFT(1, 15, u16, 1 << 15, false); + err |= TEST_ONE_SHIFT(0xFF, 8, u16, 0xFF << 8, false); + err |= TEST_ONE_SHIFT(1, 0, int, 1 << 0, false); + err |= TEST_ONE_SHIFT(1, 16, int, 1 << 16, false); + err |= TEST_ONE_SHIFT(1, 30, int, 1 << 30, false); + err |= TEST_ONE_SHIFT(1, 0, s32, 1 << 0, false); + err |= TEST_ONE_SHIFT(1, 16, s32, 1 << 16, false); + err |= TEST_ONE_SHIFT(1, 30, s32, 1 << 30, false); + err |= TEST_ONE_SHIFT(1, 0, unsigned int, 1U << 0, false); + err |= TEST_ONE_SHIFT(1, 20, unsigned int, 1U << 20, false); + err |= TEST_ONE_SHIFT(1, 31, unsigned int, 1U << 31, false); + err |= TEST_ONE_SHIFT(0xFFFFU, 16, unsigned int, 0xFFFFU << 16, false); + err |= TEST_ONE_SHIFT(1, 0, u32, 1U << 0, false); + err |= TEST_ONE_SHIFT(1, 20, u32, 1U << 20, false); + err |= TEST_ONE_SHIFT(1, 31, u32, 1U << 31, false); + err |= TEST_ONE_SHIFT(0xFFFFU, 16, u32, 0xFFFFU << 16, false); + err |= TEST_ONE_SHIFT(1, 0, u64, 1ULL << 0, false); + err |= TEST_ONE_SHIFT(1, 40, u64, 1ULL << 40, false); + err |= TEST_ONE_SHIFT(1, 63, u64, 1ULL << 63, false); + err |= TEST_ONE_SHIFT(0xFFFFFFFFULL, 32, u64, + 0xFFFFFFFFULL << 32, false); + + /* Sane shift: start and end with 0, without a too-wide shift. */ + err |= TEST_ONE_SHIFT(0, 7, u8, 0, false); + err |= TEST_ONE_SHIFT(0, 15, u16, 0, false); + err |= TEST_ONE_SHIFT(0, 31, unsigned int, 0, false); + err |= TEST_ONE_SHIFT(0, 31, u32, 0, false); + err |= TEST_ONE_SHIFT(0, 63, u64, 0, false); + + /* Sane shift: start and end with 0, without reaching signed bit. */ + err |= TEST_ONE_SHIFT(0, 6, s8, 0, false); + err |= TEST_ONE_SHIFT(0, 14, s16, 0, false); + err |= TEST_ONE_SHIFT(0, 30, int, 0, false); + err |= TEST_ONE_SHIFT(0, 30, s32, 0, false); + err |= TEST_ONE_SHIFT(0, 62, s64, 0, false); + + /* Overflow: shifted the bit off the end. */ + err |= TEST_ONE_SHIFT(1, 8, u8, 0, true); + err |= TEST_ONE_SHIFT(1, 16, u16, 0, true); + err |= TEST_ONE_SHIFT(1, 32, unsigned int, 0, true); + err |= TEST_ONE_SHIFT(1, 32, u32, 0, true); + err |= TEST_ONE_SHIFT(1, 64, u64, 0, true); + + /* Overflow: shifted into the signed bit. */ + err |= TEST_ONE_SHIFT(1, 7, s8, 0, true); + err |= TEST_ONE_SHIFT(1, 15, s16, 0, true); + err |= TEST_ONE_SHIFT(1, 31, int, 0, true); + err |= TEST_ONE_SHIFT(1, 31, s32, 0, true); + err |= TEST_ONE_SHIFT(1, 63, s64, 0, true); + + /* Overflow: high bit falls off unsigned types. */ + /* 10010110 */ + err |= TEST_ONE_SHIFT(150, 1, u8, 0, true); + /* 1000100010010110 */ + err |= TEST_ONE_SHIFT(34966, 1, u16, 0, true); + /* 10000100000010001000100010010110 */ + err |= TEST_ONE_SHIFT(2215151766U, 1, u32, 0, true); + err |= TEST_ONE_SHIFT(2215151766U, 1, unsigned int, 0, true); + /* 1000001000010000010000000100000010000100000010001000100010010110 */ + err |= TEST_ONE_SHIFT(9372061470395238550ULL, 1, u64, 0, true); + + /* Overflow: bit shifted into signed bit on signed types. */ + /* 01001011 */ + err |= TEST_ONE_SHIFT(75, 1, s8, 0, true); + /* 0100010001001011 */ + err |= TEST_ONE_SHIFT(17483, 1, s16, 0, true); + /* 01000010000001000100010001001011 */ + err |= TEST_ONE_SHIFT(1107575883, 1, s32, 0, true); + err |= TEST_ONE_SHIFT(1107575883, 1, int, 0, true); + /* 0100000100001000001000000010000001000010000001000100010001001011 */ + err |= TEST_ONE_SHIFT(4686030735197619275LL, 1, s64, 0, true); + + /* Overflow: bit shifted past signed bit on signed types. */ + /* 01001011 */ + err |= TEST_ONE_SHIFT(75, 2, s8, 0, true); + /* 0100010001001011 */ + err |= TEST_ONE_SHIFT(17483, 2, s16, 0, true); + /* 01000010000001000100010001001011 */ + err |= TEST_ONE_SHIFT(1107575883, 2, s32, 0, true); + err |= TEST_ONE_SHIFT(1107575883, 2, int, 0, true); + /* 0100000100001000001000000010000001000010000001000100010001001011 */ + err |= TEST_ONE_SHIFT(4686030735197619275LL, 2, s64, 0, true); + + /* Overflow: values larger than destination type. */ + err |= TEST_ONE_SHIFT(0x100, 0, u8, 0, true); + err |= TEST_ONE_SHIFT(0xFF, 0, s8, 0, true); + err |= TEST_ONE_SHIFT(0x10000U, 0, u16, 0, true); + err |= TEST_ONE_SHIFT(0xFFFFU, 0, s16, 0, true); + err |= TEST_ONE_SHIFT(0x100000000ULL, 0, u32, 0, true); + err |= TEST_ONE_SHIFT(0x100000000ULL, 0, unsigned int, 0, true); + err |= TEST_ONE_SHIFT(0xFFFFFFFFUL, 0, s32, 0, true); + err |= TEST_ONE_SHIFT(0xFFFFFFFFUL, 0, int, 0, true); + err |= TEST_ONE_SHIFT(0xFFFFFFFFFFFFFFFFULL, 0, s64, 0, true); + + /* Nonsense: negative initial value. */ + err |= TEST_ONE_SHIFT(-1, 0, s8, 0, true); + err |= TEST_ONE_SHIFT(-1, 0, u8, 0, true); + err |= TEST_ONE_SHIFT(-5, 0, s16, 0, true); + err |= TEST_ONE_SHIFT(-5, 0, u16, 0, true); + err |= TEST_ONE_SHIFT(-10, 0, int, 0, true); + err |= TEST_ONE_SHIFT(-10, 0, unsigned int, 0, true); + err |= TEST_ONE_SHIFT(-100, 0, s32, 0, true); + err |= TEST_ONE_SHIFT(-100, 0, u32, 0, true); + err |= TEST_ONE_SHIFT(-10000, 0, s64, 0, true); + err |= TEST_ONE_SHIFT(-10000, 0, u64, 0, true); + + /* Nonsense: negative shift values. */ + err |= TEST_ONE_SHIFT(0, -5, s8, 0, true); + err |= TEST_ONE_SHIFT(0, -5, u8, 0, true); + err |= TEST_ONE_SHIFT(0, -10, s16, 0, true); + err |= TEST_ONE_SHIFT(0, -10, u16, 0, true); + err |= TEST_ONE_SHIFT(0, -15, int, 0, true); + err |= TEST_ONE_SHIFT(0, -15, unsigned int, 0, true); + err |= TEST_ONE_SHIFT(0, -20, s32, 0, true); + err |= TEST_ONE_SHIFT(0, -20, u32, 0, true); + err |= TEST_ONE_SHIFT(0, -30, s64, 0, true); + err |= TEST_ONE_SHIFT(0, -30, u64, 0, true); + + /* Overflow: shifted at or beyond entire type's bit width. */ + err |= TEST_ONE_SHIFT(0, 8, u8, 0, true); + err |= TEST_ONE_SHIFT(0, 9, u8, 0, true); + err |= TEST_ONE_SHIFT(0, 8, s8, 0, true); + err |= TEST_ONE_SHIFT(0, 9, s8, 0, true); + err |= TEST_ONE_SHIFT(0, 16, u16, 0, true); + err |= TEST_ONE_SHIFT(0, 17, u16, 0, true); + err |= TEST_ONE_SHIFT(0, 16, s16, 0, true); + err |= TEST_ONE_SHIFT(0, 17, s16, 0, true); + err |= TEST_ONE_SHIFT(0, 32, u32, 0, true); + err |= TEST_ONE_SHIFT(0, 33, u32, 0, true); + err |= TEST_ONE_SHIFT(0, 32, int, 0, true); + err |= TEST_ONE_SHIFT(0, 33, int, 0, true); + err |= TEST_ONE_SHIFT(0, 32, s32, 0, true); + err |= TEST_ONE_SHIFT(0, 33, s32, 0, true); + err |= TEST_ONE_SHIFT(0, 64, u64, 0, true); + err |= TEST_ONE_SHIFT(0, 65, u64, 0, true); + err |= TEST_ONE_SHIFT(0, 64, s64, 0, true); + err |= TEST_ONE_SHIFT(0, 65, s64, 0, true); + + /* + * Corner case: for unsigned types, we fail when we've shifted + * through the entire width of bits. For signed types, we might + * want to match this behavior, but that would mean noticing if + * we shift through all but the signed bit, and this is not + * currently detected (but we'll notice an overflow into the + * signed bit). So, for now, we will test this condition but + * mark it as not expected to overflow. + */ + err |= TEST_ONE_SHIFT(0, 7, s8, 0, false); + err |= TEST_ONE_SHIFT(0, 15, s16, 0, false); + err |= TEST_ONE_SHIFT(0, 31, int, 0, false); + err |= TEST_ONE_SHIFT(0, 31, s32, 0, false); + err |= TEST_ONE_SHIFT(0, 63, s64, 0, false); + + return err; +} + +/* + * Deal with the various forms of allocator arguments. See comments above + * the DEFINE_TEST_ALLOC() instances for mapping of the "bits". + */ +#define alloc_GFP (GFP_KERNEL | __GFP_NOWARN) +#define alloc010(alloc, arg, sz) alloc(sz, alloc_GFP) +#define alloc011(alloc, arg, sz) alloc(sz, alloc_GFP, NUMA_NO_NODE) +#define alloc000(alloc, arg, sz) alloc(sz) +#define alloc001(alloc, arg, sz) alloc(sz, NUMA_NO_NODE) +#define alloc110(alloc, arg, sz) alloc(arg, sz, alloc_GFP) +#define free0(free, arg, ptr) free(ptr) +#define free1(free, arg, ptr) free(arg, ptr) + +/* Wrap around to 16K */ +#define TEST_SIZE (5 * 4096) + +#define DEFINE_TEST_ALLOC(func, free_func, want_arg, want_gfp, want_node)\ +static int __init test_ ## func (void *arg) \ +{ \ + volatile size_t a = TEST_SIZE; \ + volatile size_t b = (SIZE_MAX / TEST_SIZE) + 1; \ + void *ptr; \ + \ + /* Tiny allocation test. */ \ + ptr = alloc ## want_arg ## want_gfp ## want_node (func, arg, 1);\ + if (!ptr) { \ + pr_warn(#func " failed regular allocation?!\n"); \ + return 1; \ + } \ + free ## want_arg (free_func, arg, ptr); \ + \ + /* Wrapped allocation test. */ \ + ptr = alloc ## want_arg ## want_gfp ## want_node (func, arg, \ + a * b); \ + if (!ptr) { \ + pr_warn(#func " unexpectedly failed bad wrapping?!\n"); \ + return 1; \ + } \ + free ## want_arg (free_func, arg, ptr); \ + \ + /* Saturated allocation test. */ \ + ptr = alloc ## want_arg ## want_gfp ## want_node (func, arg, \ + array_size(a, b)); \ + if (ptr) { \ + pr_warn(#func " missed saturation!\n"); \ + free ## want_arg (free_func, arg, ptr); \ + return 1; \ + } \ + pr_info(#func " detected saturation\n"); \ + return 0; \ +} + +/* + * Allocator uses a trailing node argument --------+ (e.g. kmalloc_node()) + * Allocator uses the gfp_t argument -----------+ | (e.g. kmalloc()) + * Allocator uses a special leading argument + | | (e.g. devm_kmalloc()) + * | | | + */ +DEFINE_TEST_ALLOC(kmalloc, kfree, 0, 1, 0); +DEFINE_TEST_ALLOC(kmalloc_node, kfree, 0, 1, 1); +DEFINE_TEST_ALLOC(kzalloc, kfree, 0, 1, 0); +DEFINE_TEST_ALLOC(kzalloc_node, kfree, 0, 1, 1); +DEFINE_TEST_ALLOC(vmalloc, vfree, 0, 0, 0); +DEFINE_TEST_ALLOC(vmalloc_node, vfree, 0, 0, 1); +DEFINE_TEST_ALLOC(vzalloc, vfree, 0, 0, 0); +DEFINE_TEST_ALLOC(vzalloc_node, vfree, 0, 0, 1); +DEFINE_TEST_ALLOC(kvmalloc, kvfree, 0, 1, 0); +DEFINE_TEST_ALLOC(kvmalloc_node, kvfree, 0, 1, 1); +DEFINE_TEST_ALLOC(kvzalloc, kvfree, 0, 1, 0); +DEFINE_TEST_ALLOC(kvzalloc_node, kvfree, 0, 1, 1); +DEFINE_TEST_ALLOC(devm_kmalloc, devm_kfree, 1, 1, 0); +DEFINE_TEST_ALLOC(devm_kzalloc, devm_kfree, 1, 1, 0); + +static int __init test_overflow_allocation(void) +{ + const char device_name[] = "overflow-test"; + struct device *dev; + int err = 0; + + /* Create dummy device for devm_kmalloc()-family tests. */ + dev = root_device_register(device_name); + if (IS_ERR(dev)) { + pr_warn("Cannot register test device\n"); + return 1; + } + + err |= test_kmalloc(NULL); + err |= test_kmalloc_node(NULL); + err |= test_kzalloc(NULL); + err |= test_kzalloc_node(NULL); + err |= test_kvmalloc(NULL); + err |= test_kvmalloc_node(NULL); + err |= test_kvzalloc(NULL); + err |= test_kvzalloc_node(NULL); + err |= test_vmalloc(NULL); + err |= test_vmalloc_node(NULL); + err |= test_vzalloc(NULL); + err |= test_vzalloc_node(NULL); + err |= test_devm_kmalloc(dev); + err |= test_devm_kzalloc(dev); + + device_unregister(dev); + + return err; +} + +struct __test_flex_array { + unsigned long flags; + size_t count; + unsigned long data[]; +}; + +static int __init test_overflow_size_helpers(void) +{ + struct __test_flex_array *obj; + int count = 0; + int err = 0; + int var; + +#define check_one_size_helper(expected, func, args...) ({ \ + bool __failure = false; \ + size_t _r; \ + \ + _r = func(args); \ + if (_r != (expected)) { \ + pr_warn("expected " #func "(" #args ") " \ + "to return %zu but got %zu instead\n", \ + (size_t)(expected), _r); \ + __failure = true; \ + } \ + count++; \ + __failure; \ +}) + + var = 4; + err |= check_one_size_helper(20, size_mul, var++, 5); + err |= check_one_size_helper(20, size_mul, 4, var++); + err |= check_one_size_helper(0, size_mul, 0, 3); + err |= check_one_size_helper(0, size_mul, 3, 0); + err |= check_one_size_helper(6, size_mul, 2, 3); + err |= check_one_size_helper(SIZE_MAX, size_mul, SIZE_MAX, 1); + err |= check_one_size_helper(SIZE_MAX, size_mul, SIZE_MAX, 3); + err |= check_one_size_helper(SIZE_MAX, size_mul, SIZE_MAX, -3); + + var = 4; + err |= check_one_size_helper(9, size_add, var++, 5); + err |= check_one_size_helper(9, size_add, 4, var++); + err |= check_one_size_helper(9, size_add, 9, 0); + err |= check_one_size_helper(9, size_add, 0, 9); + err |= check_one_size_helper(5, size_add, 2, 3); + err |= check_one_size_helper(SIZE_MAX, size_add, SIZE_MAX, 1); + err |= check_one_size_helper(SIZE_MAX, size_add, SIZE_MAX, 3); + err |= check_one_size_helper(SIZE_MAX, size_add, SIZE_MAX, -3); + + var = 4; + err |= check_one_size_helper(1, size_sub, var--, 3); + err |= check_one_size_helper(1, size_sub, 4, var--); + err |= check_one_size_helper(1, size_sub, 3, 2); + err |= check_one_size_helper(9, size_sub, 9, 0); + err |= check_one_size_helper(SIZE_MAX, size_sub, 9, -3); + err |= check_one_size_helper(SIZE_MAX, size_sub, 0, 9); + err |= check_one_size_helper(SIZE_MAX, size_sub, 2, 3); + err |= check_one_size_helper(SIZE_MAX, size_sub, SIZE_MAX, 0); + err |= check_one_size_helper(SIZE_MAX, size_sub, SIZE_MAX, 10); + err |= check_one_size_helper(SIZE_MAX, size_sub, 0, SIZE_MAX); + err |= check_one_size_helper(SIZE_MAX, size_sub, 14, SIZE_MAX); + err |= check_one_size_helper(SIZE_MAX - 2, size_sub, SIZE_MAX - 1, 1); + err |= check_one_size_helper(SIZE_MAX - 4, size_sub, SIZE_MAX - 1, 3); + err |= check_one_size_helper(1, size_sub, SIZE_MAX - 1, -3); + + var = 4; + err |= check_one_size_helper(4 * sizeof(*obj->data), + flex_array_size, obj, data, var++); + err |= check_one_size_helper(5 * sizeof(*obj->data), + flex_array_size, obj, data, var++); + err |= check_one_size_helper(0, flex_array_size, obj, data, 0); + err |= check_one_size_helper(sizeof(*obj->data), + flex_array_size, obj, data, 1); + err |= check_one_size_helper(7 * sizeof(*obj->data), + flex_array_size, obj, data, 7); + err |= check_one_size_helper(SIZE_MAX, + flex_array_size, obj, data, -1); + err |= check_one_size_helper(SIZE_MAX, + flex_array_size, obj, data, SIZE_MAX - 4); + + var = 4; + err |= check_one_size_helper(sizeof(*obj) + (4 * sizeof(*obj->data)), + struct_size, obj, data, var++); + err |= check_one_size_helper(sizeof(*obj) + (5 * sizeof(*obj->data)), + struct_size, obj, data, var++); + err |= check_one_size_helper(sizeof(*obj), struct_size, obj, data, 0); + err |= check_one_size_helper(sizeof(*obj) + sizeof(*obj->data), + struct_size, obj, data, 1); + err |= check_one_size_helper(SIZE_MAX, + struct_size, obj, data, -3); + err |= check_one_size_helper(SIZE_MAX, + struct_size, obj, data, SIZE_MAX - 3); + + pr_info("%d overflow size helper tests finished\n", count); + + return err; +} + +static int __init test_module_init(void) +{ + int err = 0; + + err |= test_overflow_calculation(); + err |= test_overflow_shift(); + err |= test_overflow_size_helpers(); + err |= test_overflow_allocation(); + + if (err) { + pr_warn("FAIL!\n"); + err = -EINVAL; + } else { + pr_info("all tests passed\n"); + } + + return err; +} + +static void __exit test_module_exit(void) +{ } + +module_init(test_module_init); +module_exit(test_module_exit); +MODULE_LICENSE("Dual MIT/GPL"); |