diff options
Diffstat (limited to 'tools/testing/selftests/mm/mdwe_test.c')
| -rw-r--r-- | tools/testing/selftests/mm/mdwe_test.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/mdwe_test.c b/tools/testing/selftests/mm/mdwe_test.c new file mode 100644 index 0000000000..0c5e469ae3 --- /dev/null +++ b/tools/testing/selftests/mm/mdwe_test.c @@ -0,0 +1,193 @@ +// SPDX-License-Identifier: GPL-2.0 + +#ifdef __aarch64__ +#include <asm/hwcap.h> +#endif + +#include <linux/mman.h> +#include <linux/prctl.h> + +#include <stdio.h> +#include <stdlib.h> +#include <sys/auxv.h> +#include <sys/prctl.h> +#include <sys/wait.h> +#include <unistd.h> + +#include "../kselftest_harness.h" + +#ifndef __aarch64__ +# define PROT_BTI 0 +#endif + +TEST(prctl_flags) +{ + EXPECT_LT(prctl(PR_SET_MDWE, 7L, 0L, 0L, 0L), 0); + EXPECT_LT(prctl(PR_SET_MDWE, 0L, 7L, 0L, 0L), 0); + EXPECT_LT(prctl(PR_SET_MDWE, 0L, 0L, 7L, 0L), 0); + EXPECT_LT(prctl(PR_SET_MDWE, 0L, 0L, 0L, 7L), 0); + + EXPECT_LT(prctl(PR_GET_MDWE, 7L, 0L, 0L, 0L), 0); + EXPECT_LT(prctl(PR_GET_MDWE, 0L, 7L, 0L, 0L), 0); + EXPECT_LT(prctl(PR_GET_MDWE, 0L, 0L, 7L, 0L), 0); + EXPECT_LT(prctl(PR_GET_MDWE, 0L, 0L, 0L, 7L), 0); +} + +FIXTURE(mdwe) +{ + void *p; + int flags; + size_t size; + pid_t pid; +}; + +FIXTURE_VARIANT(mdwe) +{ + bool enabled; + bool forked; +}; + +FIXTURE_VARIANT_ADD(mdwe, stock) +{ + .enabled = false, + .forked = false, +}; + +FIXTURE_VARIANT_ADD(mdwe, enabled) +{ + .enabled = true, + .forked = false, +}; + +FIXTURE_VARIANT_ADD(mdwe, forked) +{ + .enabled = true, + .forked = true, +}; + +FIXTURE_SETUP(mdwe) +{ + int ret, status; + + self->p = NULL; + self->flags = MAP_SHARED | MAP_ANONYMOUS; + self->size = getpagesize(); + + if (!variant->enabled) + return; + + ret = prctl(PR_SET_MDWE, PR_MDWE_REFUSE_EXEC_GAIN, 0L, 0L, 0L); + ASSERT_EQ(ret, 0) { + TH_LOG("PR_SET_MDWE failed or unsupported"); + } + + ret = prctl(PR_GET_MDWE, 0L, 0L, 0L, 0L); + ASSERT_EQ(ret, 1); + + if (variant->forked) { + self->pid = fork(); + ASSERT_GE(self->pid, 0) { + TH_LOG("fork failed\n"); + } + + if (self->pid > 0) { + ret = waitpid(self->pid, &status, 0); + ASSERT_TRUE(WIFEXITED(status)); + exit(WEXITSTATUS(status)); + } + } +} + +FIXTURE_TEARDOWN(mdwe) +{ + if (self->p && self->p != MAP_FAILED) + munmap(self->p, self->size); +} + +TEST_F(mdwe, mmap_READ_EXEC) +{ + self->p = mmap(NULL, self->size, PROT_READ | PROT_EXEC, self->flags, 0, 0); + EXPECT_NE(self->p, MAP_FAILED); +} + +TEST_F(mdwe, mmap_WRITE_EXEC) +{ + self->p = mmap(NULL, self->size, PROT_WRITE | PROT_EXEC, self->flags, 0, 0); + if (variant->enabled) { + EXPECT_EQ(self->p, MAP_FAILED); + } else { + EXPECT_NE(self->p, MAP_FAILED); + } +} + +TEST_F(mdwe, mprotect_stay_EXEC) +{ + int ret; + + self->p = mmap(NULL, self->size, PROT_READ | PROT_EXEC, self->flags, 0, 0); + ASSERT_NE(self->p, MAP_FAILED); + + ret = mprotect(self->p, self->size, PROT_READ | PROT_EXEC); + EXPECT_EQ(ret, 0); +} + +TEST_F(mdwe, mprotect_add_EXEC) +{ + int ret; + + self->p = mmap(NULL, self->size, PROT_READ, self->flags, 0, 0); + ASSERT_NE(self->p, MAP_FAILED); + + ret = mprotect(self->p, self->size, PROT_READ | PROT_EXEC); + if (variant->enabled) { + EXPECT_LT(ret, 0); + } else { + EXPECT_EQ(ret, 0); + } +} + +TEST_F(mdwe, mprotect_WRITE_EXEC) +{ + int ret; + + self->p = mmap(NULL, self->size, PROT_WRITE, self->flags, 0, 0); + ASSERT_NE(self->p, MAP_FAILED); + + ret = mprotect(self->p, self->size, PROT_WRITE | PROT_EXEC); + if (variant->enabled) { + EXPECT_LT(ret, 0); + } else { + EXPECT_EQ(ret, 0); + } +} + +TEST_F(mdwe, mmap_FIXED) +{ + void *p; + + self->p = mmap(NULL, self->size, PROT_READ, self->flags, 0, 0); + ASSERT_NE(self->p, MAP_FAILED); + + /* MAP_FIXED unmaps the existing page before mapping which is allowed */ + p = mmap(self->p, self->size, PROT_READ | PROT_EXEC, + self->flags | MAP_FIXED, 0, 0); + EXPECT_EQ(p, self->p); +} + +TEST_F(mdwe, arm64_BTI) +{ + int ret; + +#ifdef __aarch64__ + if (!(getauxval(AT_HWCAP2) & HWCAP2_BTI)) +#endif + SKIP(return, "HWCAP2_BTI not supported"); + + self->p = mmap(NULL, self->size, PROT_EXEC, self->flags, 0, 0); + ASSERT_NE(self->p, MAP_FAILED); + + ret = mprotect(self->p, self->size, PROT_EXEC | PROT_BTI); + EXPECT_EQ(ret, 0); +} + +TEST_HARNESS_MAIN |