From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- fs/ext4/hash-test.c | 567 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 567 insertions(+) create mode 100644 fs/ext4/hash-test.c (limited to 'fs/ext4/hash-test.c') diff --git a/fs/ext4/hash-test.c b/fs/ext4/hash-test.c new file mode 100644 index 000000000..49b0d874c --- /dev/null +++ b/fs/ext4/hash-test.c @@ -0,0 +1,567 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KUnit tests for ext4 directory hash computation. + */ + +#include +#include +#include +#include +#include +#include +#include "ext4.h" + +static void ext4_hash_init_fake_dir(struct inode *dir, struct super_block *sb) +{ + memset(sb, 0, sizeof(*sb)); + memset(dir, 0, sizeof(*dir)); + dir->i_sb = sb; + strscpy(sb->s_id, "kunit-ext4", sizeof(sb->s_id)); +} + +static void ext4_hash_init_fake_dir_with_sbi(struct inode *dir, + struct super_block *sb, + struct ext4_sb_info *sbi) +{ + ext4_hash_init_fake_dir(dir, sb); + memset(sbi, 0, sizeof(*sbi)); + sb->s_fs_info = sbi; + sbi->s_sb = sb; +} + +#ifdef CONFIG_FS_ENCRYPTION +static const struct fscrypt_operations ext4_hash_test_cryptops = { + .inode_info_offs = + (int)offsetof(struct ext4_inode_info, i_crypt_info) - + (int)offsetof(struct ext4_inode_info, vfs_inode), +}; +#endif + +static void ext4_hash_init_fake_ext4_dir(struct ext4_inode_info *ei, + struct super_block *sb, + struct ext4_sb_info *sbi) +{ + struct inode *dir = &ei->vfs_inode; + + memset(sb, 0, sizeof(*sb)); + memset(ei, 0, sizeof(*ei)); + memset(sbi, 0, sizeof(*sbi)); + + strscpy(sb->s_id, "kunit-ext4", sizeof(sb->s_id)); + sb->s_fs_info = sbi; + sbi->s_sb = sb; + + dir->i_sb = sb; + dir->i_mode = S_IFDIR; + +#ifdef CONFIG_FS_ENCRYPTION + fscrypt_set_ops(sb, &ext4_hash_test_cryptops); +#endif +} + +struct ext4_dirhash_test_case { + const char *name; + u32 hash_version; + const char *input; + int len; + u32 seed[4]; + bool use_seed; + u32 expected_hash; + u32 expected_minor_hash; +}; + +static const struct ext4_dirhash_test_case ext4_dirhash_test_cases[] = { + { + .name = "legacy_abc", + .hash_version = DX_HASH_LEGACY, + .input = "abc", + .len = 3, + .use_seed = false, + .expected_hash = 0x75afd992, + .expected_minor_hash = 0x00000000, + }, + { + .name = "legacy_unsigned_abc", + .hash_version = DX_HASH_LEGACY_UNSIGNED, + .input = "abc", + .len = 3, + .use_seed = false, + .expected_hash = 0x75afd992, + .expected_minor_hash = 0x00000000, + }, + { + .name = "half_md4_abc", + .hash_version = DX_HASH_HALF_MD4, + .input = "abc", + .len = 3, + .use_seed = false, + .expected_hash = 0xd196a868, + .expected_minor_hash = 0xc420eb28, + }, + { + .name = "half_md4_unsigned_abc", + .hash_version = DX_HASH_HALF_MD4_UNSIGNED, + .input = "abc", + .len = 3, + .use_seed = false, + .expected_hash = 0xd196a868, + .expected_minor_hash = 0xc420eb28, + }, + { + .name = "tea_abc", + .hash_version = DX_HASH_TEA, + .input = "abc", + .len = 3, + .use_seed = false, + .expected_hash = 0xb1435ec4, + .expected_minor_hash = 0x3f7eaa0e, + }, + { + .name = "tea_unsigned_abc", + .hash_version = DX_HASH_TEA_UNSIGNED, + .input = "abc", + .len = 3, + .use_seed = false, + .expected_hash = 0xb1435ec4, + .expected_minor_hash = 0x3f7eaa0e, + }, + { + .name = "empty_half_md4", + .hash_version = DX_HASH_HALF_MD4, + .input = "", + .len = 0, + .use_seed = false, + .expected_hash = 0xefcdab88, + .expected_minor_hash = 0x98badcfe, + }, + { + .name = "half_md4_31bytes", + .hash_version = DX_HASH_HALF_MD4, + .input = "1234567890123456789012345678901", + .len = 31, + .use_seed = false, + .expected_hash = 0xc4db1f78, + .expected_minor_hash = 0xea23921b, + }, + { + .name = "half_md4_32bytes", + .hash_version = DX_HASH_HALF_MD4, + .input = "12345678901234567890123456789012", + .len = 32, + .use_seed = false, + .expected_hash = 0xfa6cc63e, + .expected_minor_hash = 0x2f77bd1c, + }, + { + .name = "half_md4_33bytes", + .hash_version = DX_HASH_HALF_MD4, + .input = "123456789012345678901234567890123", + .len = 33, + .use_seed = false, + .expected_hash = 0xdc0c2dec, + .expected_minor_hash = 0x5ca23365, + }, + { + .name = "half_md4_unsigned_31bytes", + .hash_version = DX_HASH_HALF_MD4_UNSIGNED, + .input = "1234567890123456789012345678901", + .len = 31, + .use_seed = false, + .expected_hash = 0xc4db1f78, + .expected_minor_hash = 0xea23921b, + }, + { + .name = "half_md4_unsigned_32bytes", + .hash_version = DX_HASH_HALF_MD4_UNSIGNED, + .input = "12345678901234567890123456789012", + .len = 32, + .use_seed = false, + .expected_hash = 0xfa6cc63e, + .expected_minor_hash = 0x2f77bd1c, + }, + { + .name = "half_md4_unsigned_33bytes", + .hash_version = DX_HASH_HALF_MD4_UNSIGNED, + .input = "123456789012345678901234567890123", + .len = 33, + .use_seed = false, + .expected_hash = 0xdc0c2dec, + .expected_minor_hash = 0x5ca23365, + }, + { + .name = "tea_15bytes", + .hash_version = DX_HASH_TEA, + .input = "123456789abcdef", + .len = 15, + .use_seed = false, + .expected_hash = 0xa562903a, + .expected_minor_hash = 0x6174a00f, + }, + { + .name = "tea_16bytes", + .hash_version = DX_HASH_TEA, + .input = "1234567890abcdef", + .len = 16, + .use_seed = false, + .expected_hash = 0x8449f258, + .expected_minor_hash = 0x49a16d46, + }, + { + .name = "tea_17bytes", + .hash_version = DX_HASH_TEA, + .input = "123456789abcdefgh", + .len = 17, + .use_seed = false, + .expected_hash = 0xf32ec10c, + .expected_minor_hash = 0x58ceae61, + }, + { + .name = "half_md4_seeded", + .hash_version = DX_HASH_HALF_MD4, + .input = "same-name", + .len = 9, + .seed = { 0x11111111, 0x22222222, 0x33333333, 0x44444444 }, + .use_seed = true, + .expected_hash = 0x8aebf604, + .expected_minor_hash = 0x66ce48fe, + }, + { + .name = "half_md4_non_ascii_signed", + .hash_version = DX_HASH_HALF_MD4, + .input = "\x80\x81\x82\x83\x84", + .len = 5, + .use_seed = false, + .expected_hash = 0x8bab0498, + .expected_minor_hash = 0xc326632d, + }, + { + .name = "half_md4_non_ascii_unsigned", + .hash_version = DX_HASH_HALF_MD4_UNSIGNED, + .input = "\x80\x81\x82\x83\x84", + .len = 5, + .use_seed = false, + .expected_hash = 0xbc48596e, + .expected_minor_hash = 0xde0fad41, + }, + { + .name = "tea_non_ascii_signed", + .hash_version = DX_HASH_TEA, + .input = "\x80\x81\x82\x83\x84", + .len = 5, + .use_seed = false, + .expected_hash = 0x21e3a154, + .expected_minor_hash = 0x90112c3d, + }, + { + .name = "tea_non_ascii_unsigned", + .hash_version = DX_HASH_TEA_UNSIGNED, + .input = "\x80\x81\x82\x83\x84", + .len = 5, + .use_seed = false, + .expected_hash = 0x9b648616, + .expected_minor_hash = 0x011dd507, + }, +}; + +static void test_ext4fs_dirhash_vectors(struct kunit *test) +{ + struct super_block *sb; + struct inode *dir; + int i; + + sb = kunit_kzalloc(test, sizeof(*sb), GFP_KERNEL); + dir = kunit_kzalloc(test, sizeof(*dir), GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, sb); + KUNIT_ASSERT_NOT_NULL(test, dir); + + ext4_hash_init_fake_dir(dir, sb); + + for (i = 0; i < ARRAY_SIZE(ext4_dirhash_test_cases); i++) { + const struct ext4_dirhash_test_case *tc = + &ext4_dirhash_test_cases[i]; + struct dx_hash_info hinfo; + int ret; + + memset(&hinfo, 0, sizeof(hinfo)); + hinfo.hash_version = tc->hash_version; + hinfo.seed = tc->use_seed ? (u32 *)tc->seed : NULL; + + ret = ext4fs_dirhash(dir, tc->input, tc->len, &hinfo); + + KUNIT_ASSERT_EQ_MSG(test, ret, 0, "case=%s", tc->name); + KUNIT_EXPECT_EQ_MSG(test, hinfo.hash, tc->expected_hash, + "case=%s", tc->name); + KUNIT_EXPECT_EQ_MSG(test, hinfo.minor_hash, + tc->expected_minor_hash, + "case=%s", tc->name); + } +} + +static void test_ext4fs_dirhash_seed_changes_result(struct kunit *test) +{ + struct super_block *sb; + struct inode *dir; + u32 seed[4] = { 0x11111111, 0x22222222, 0x33333333, 0x44444444 }; + struct dx_hash_info plain = { + .hash_version = DX_HASH_HALF_MD4, + }; + struct dx_hash_info seeded = { + .hash_version = DX_HASH_HALF_MD4, + .seed = seed, + }; + int ret_plain, ret_seeded; + + sb = kunit_kzalloc(test, sizeof(*sb), GFP_KERNEL); + dir = kunit_kzalloc(test, sizeof(*dir), GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, sb); + KUNIT_ASSERT_NOT_NULL(test, dir); + + ext4_hash_init_fake_dir(dir, sb); + + ret_plain = ext4fs_dirhash(dir, "same-name", 9, &plain); + ret_seeded = ext4fs_dirhash(dir, "same-name", 9, &seeded); + + KUNIT_ASSERT_EQ(test, ret_plain, 0); + KUNIT_ASSERT_EQ(test, ret_seeded, 0); + + KUNIT_EXPECT_TRUE(test, + plain.hash != seeded.hash || + plain.minor_hash != seeded.minor_hash); +} + +static void test_ext4fs_dirhash_invalid_version_returns_einval(struct kunit *test) +{ + struct super_block *sb; + struct inode *dir; + struct ext4_sb_info *sbi; + struct dx_hash_info hinfo = { + .hash = 0xdeadbeef, + .minor_hash = 0xcafebabe, + .hash_version = DX_HASH_LAST + 1, + }; + int ret; + + sb = kunit_kzalloc(test, sizeof(*sb), GFP_KERNEL); + dir = kunit_kzalloc(test, sizeof(*dir), GFP_KERNEL); + sbi = kunit_kzalloc(test, sizeof(*sbi), GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, sb); + KUNIT_ASSERT_NOT_NULL(test, dir); + KUNIT_ASSERT_NOT_NULL(test, sbi); + + ext4_hash_init_fake_dir_with_sbi(dir, sb, sbi); + + ret = ext4fs_dirhash(dir, "abc", 3, &hinfo); + + KUNIT_EXPECT_EQ(test, ret, -EINVAL); + KUNIT_EXPECT_EQ(test, hinfo.hash, 0); + KUNIT_EXPECT_EQ(test, hinfo.minor_hash, 0); +} + +static void test_ext4fs_dirhash_siphash_without_key_returns_einval(struct kunit *test) +{ + struct super_block *sb; + struct ext4_inode_info *ei; + struct inode *dir; + struct ext4_sb_info *sbi; + struct dx_hash_info hinfo = { + .hash_version = DX_HASH_SIPHASH, + }; + int ret; + + sb = kunit_kzalloc(test, sizeof(*sb), GFP_KERNEL); + ei = kunit_kzalloc(test, sizeof(*ei), GFP_KERNEL); + sbi = kunit_kzalloc(test, sizeof(*sbi), GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, sb); + KUNIT_ASSERT_NOT_NULL(test, ei); + KUNIT_ASSERT_NOT_NULL(test, sbi); + + ext4_hash_init_fake_ext4_dir(ei, sb, sbi); + dir = &ei->vfs_inode; + + ret = ext4fs_dirhash(dir, "name", strlen("name"), &hinfo); + + KUNIT_EXPECT_EQ(test, ret, -EINVAL); +} + +static void test_ext4fs_dirhash_signed_unsigned_differ_on_nonascii(struct kunit *test) +{ + struct super_block *sb; + struct inode *dir; + static const char input[] = "\x80\xff\x81\xfe\101bc"; + struct dx_hash_info legacy_signed = { + .hash_version = DX_HASH_LEGACY, + }; + struct dx_hash_info legacy_unsigned = { + .hash_version = DX_HASH_LEGACY_UNSIGNED, + }; + struct dx_hash_info md4_signed = { + .hash_version = DX_HASH_HALF_MD4, + }; + struct dx_hash_info md4_unsigned = { + .hash_version = DX_HASH_HALF_MD4_UNSIGNED, + }; + struct dx_hash_info tea_signed = { + .hash_version = DX_HASH_TEA, + }; + struct dx_hash_info tea_unsigned = { + .hash_version = DX_HASH_TEA_UNSIGNED, + }; + int ret; + + sb = kunit_kzalloc(test, sizeof(*sb), GFP_KERNEL); + dir = kunit_kzalloc(test, sizeof(*dir), GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, sb); + KUNIT_ASSERT_NOT_NULL(test, dir); + + ext4_hash_init_fake_dir(dir, sb); + + ret = ext4fs_dirhash(dir, input, sizeof(input) - 1, &legacy_signed); + KUNIT_ASSERT_EQ(test, ret, 0); + ret = ext4fs_dirhash(dir, input, sizeof(input) - 1, &legacy_unsigned); + KUNIT_ASSERT_EQ(test, ret, 0); + KUNIT_EXPECT_NE(test, legacy_signed.hash, legacy_unsigned.hash); + + ret = ext4fs_dirhash(dir, input, sizeof(input) - 1, &md4_signed); + KUNIT_ASSERT_EQ(test, ret, 0); + ret = ext4fs_dirhash(dir, input, sizeof(input) - 1, &md4_unsigned); + KUNIT_ASSERT_EQ(test, ret, 0); + KUNIT_EXPECT_TRUE(test, + md4_signed.hash != md4_unsigned.hash || + md4_signed.minor_hash != md4_unsigned.minor_hash); + + ret = ext4fs_dirhash(dir, input, sizeof(input) - 1, &tea_signed); + KUNIT_ASSERT_EQ(test, ret, 0); + ret = ext4fs_dirhash(dir, input, sizeof(input) - 1, &tea_unsigned); + KUNIT_ASSERT_EQ(test, ret, 0); + KUNIT_EXPECT_TRUE(test, + tea_signed.hash != tea_unsigned.hash || + tea_signed.minor_hash != tea_unsigned.minor_hash); +} + +#if IS_ENABLED(CONFIG_UNICODE) +KUNIT_DEFINE_ACTION_WRAPPER(utf8_unload_action, utf8_unload, + struct unicode_map *); +static void test_ext4fs_dirhash_casefolded_names_hash_consistently(struct kunit *test) +{ + struct super_block *sb; + struct ext4_inode_info *ei; + struct ext4_sb_info *sbi; + struct unicode_map *um; + struct dx_hash_info h1 = { + .hash_version = DX_HASH_HALF_MD4, + }; + struct dx_hash_info h2 = { + .hash_version = DX_HASH_HALF_MD4, + }; + int ret, ret1, ret2; + + sb = kunit_kzalloc(test, sizeof(*sb), GFP_KERNEL); + ei = kunit_kzalloc(test, sizeof(*ei), GFP_KERNEL); + sbi = kunit_kzalloc(test, sizeof(*sbi), GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, sb); + KUNIT_ASSERT_NOT_NULL(test, ei); + KUNIT_ASSERT_NOT_NULL(test, sbi); + + um = utf8_load(UTF8_LATEST); + if (IS_ERR(um)) { + kunit_skip(test, "utf8_load(UTF8_LATEST) failed: %pe", + um); + return; + } + + ret = kunit_add_action_or_reset(test, utf8_unload_action, um); + KUNIT_ASSERT_EQ(test, ret, 0); + + ext4_hash_init_fake_ext4_dir(ei, sb, sbi); + sb->s_encoding = um; + ei->vfs_inode.i_flags |= S_CASEFOLD; + + KUNIT_ASSERT_TRUE(test, IS_CASEFOLDED(&ei->vfs_inode)); + + ret1 = ext4fs_dirhash(&ei->vfs_inode, "Alpha", 5, &h1); + ret2 = ext4fs_dirhash(&ei->vfs_inode, "aLPHa", 5, &h2); + + KUNIT_ASSERT_EQ(test, ret1, 0); + KUNIT_ASSERT_EQ(test, ret2, 0); + KUNIT_EXPECT_EQ(test, h1.hash, h2.hash); + KUNIT_EXPECT_EQ(test, h1.minor_hash, h2.minor_hash); +} + +static void test_ext4fs_dirhash_casefold_fallback(struct kunit *test) +{ + struct super_block *sb_cf, *sb_plain; + struct ext4_inode_info *ei; + struct ext4_sb_info *sbi; + struct inode *plain_dir; + struct unicode_map *um; + static const char invalid_utf8[] = "\xc3\x28"; + struct dx_hash_info folded_dir = { + .hash_version = DX_HASH_HALF_MD4, + }; + struct dx_hash_info plain = { + .hash_version = DX_HASH_HALF_MD4, + }; + int ret, ret_cf, ret_plain; + + sb_cf = kunit_kzalloc(test, sizeof(*sb_cf), GFP_KERNEL); + sb_plain = kunit_kzalloc(test, sizeof(*sb_plain), GFP_KERNEL); + ei = kunit_kzalloc(test, sizeof(*ei), GFP_KERNEL); + sbi = kunit_kzalloc(test, sizeof(*sbi), GFP_KERNEL); + plain_dir = kunit_kzalloc(test, sizeof(*plain_dir), GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, sb_cf); + KUNIT_ASSERT_NOT_NULL(test, sb_plain); + KUNIT_ASSERT_NOT_NULL(test, ei); + KUNIT_ASSERT_NOT_NULL(test, sbi); + KUNIT_ASSERT_NOT_NULL(test, plain_dir); + + um = utf8_load(UTF8_LATEST); + if (IS_ERR(um)) { + kunit_skip(test, "utf8_load(UTF8_LATEST) failed: %pe", + um); + return; + } + + ret = kunit_add_action_or_reset(test, utf8_unload_action, um); + KUNIT_ASSERT_EQ(test, ret, 0); + + ext4_hash_init_fake_ext4_dir(ei, sb_cf, sbi); + sb_cf->s_encoding = um; + ei->vfs_inode.i_flags |= S_CASEFOLD; + + KUNIT_ASSERT_TRUE(test, IS_CASEFOLDED(&ei->vfs_inode)); + + ext4_hash_init_fake_dir(plain_dir, sb_plain); + + ret_cf = ext4fs_dirhash(&ei->vfs_inode, invalid_utf8, + sizeof(invalid_utf8) - 1, &folded_dir); + ret_plain = ext4fs_dirhash(plain_dir, invalid_utf8, + sizeof(invalid_utf8) - 1, &plain); + + KUNIT_ASSERT_EQ(test, ret_cf, 0); + KUNIT_ASSERT_EQ(test, ret_plain, 0); + KUNIT_EXPECT_EQ(test, folded_dir.hash, plain.hash); + KUNIT_EXPECT_EQ(test, folded_dir.minor_hash, plain.minor_hash); +} +#endif + +static struct kunit_case ext4_hash_test_cases[] = { + KUNIT_CASE(test_ext4fs_dirhash_vectors), + KUNIT_CASE(test_ext4fs_dirhash_seed_changes_result), + KUNIT_CASE(test_ext4fs_dirhash_invalid_version_returns_einval), + KUNIT_CASE(test_ext4fs_dirhash_siphash_without_key_returns_einval), + KUNIT_CASE(test_ext4fs_dirhash_signed_unsigned_differ_on_nonascii), +#if IS_ENABLED(CONFIG_UNICODE) + KUNIT_CASE(test_ext4fs_dirhash_casefolded_names_hash_consistently), + KUNIT_CASE(test_ext4fs_dirhash_casefold_fallback), +#endif + {} +}; + +static struct kunit_suite ext4_hash_test_suite = { + .name = "ext4_hash", + .test_cases = ext4_hash_test_cases, +}; + +kunit_test_suites(&ext4_hash_test_suite); + +MODULE_LICENSE("GPL"); -- cgit v1.3.1