| /* |
| * Copyright (c) 2012 The Chromium OS Authors. All rights reserved. |
| * Use of this source code is governed by the GPLv2 license. |
| * |
| * Test code for seccomp bpf. |
| */ |
| |
| #include <asm/siginfo.h> |
| #define __have_siginfo_t 1 |
| #define __have_sigval_t 1 |
| #define __have_sigevent_t 1 |
| |
| #include <errno.h> |
| #include <linux/filter.h> |
| #include <sys/prctl.h> |
| #include <sys/ptrace.h> |
| #include <sys/types.h> |
| #include <sys/user.h> |
| #include <linux/prctl.h> |
| #include <linux/ptrace.h> |
| #include <linux/seccomp.h> |
| #include <pthread.h> |
| #include <semaphore.h> |
| #include <signal.h> |
| #include <stddef.h> |
| #include <stdbool.h> |
| #include <string.h> |
| #include <time.h> |
| #include <linux/elf.h> |
| #include <sys/uio.h> |
| #include <sys/utsname.h> |
| #include <sys/fcntl.h> |
| #include <sys/mman.h> |
| #include <sys/times.h> |
| |
| #define _GNU_SOURCE |
| #include <unistd.h> |
| #include <sys/syscall.h> |
| |
| #include "test_harness.h" |
| |
| #ifndef PR_SET_PTRACER |
| # define PR_SET_PTRACER 0x59616d61 |
| #endif |
| |
| #ifndef PR_SET_NO_NEW_PRIVS |
| #define PR_SET_NO_NEW_PRIVS 38 |
| #define PR_GET_NO_NEW_PRIVS 39 |
| #endif |
| |
| #ifndef PR_SECCOMP_EXT |
| #define PR_SECCOMP_EXT 43 |
| #endif |
| |
| #ifndef SECCOMP_EXT_ACT |
| #define SECCOMP_EXT_ACT 1 |
| #endif |
| |
| #ifndef SECCOMP_EXT_ACT_TSYNC |
| #define SECCOMP_EXT_ACT_TSYNC 1 |
| #endif |
| |
| #ifndef SECCOMP_MODE_STRICT |
| #define SECCOMP_MODE_STRICT 1 |
| #endif |
| |
| #ifndef SECCOMP_MODE_FILTER |
| #define SECCOMP_MODE_FILTER 2 |
| #endif |
| |
| #ifndef SECCOMP_RET_KILL |
| #define SECCOMP_RET_KILL 0x00000000U /* kill the task immediately */ |
| #define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */ |
| #define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */ |
| #define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */ |
| #define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */ |
| |
| /* Masks for the return value sections. */ |
| #define SECCOMP_RET_ACTION 0x7fff0000U |
| #define SECCOMP_RET_DATA 0x0000ffffU |
| |
| struct seccomp_data { |
| int nr; |
| __u32 arch; |
| __u64 instruction_pointer; |
| __u64 args[6]; |
| }; |
| #endif |
| |
| #if __BYTE_ORDER == __LITTLE_ENDIAN |
| #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n])) |
| #elif __BYTE_ORDER == __BIG_ENDIAN |
| #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]) + sizeof(__u32)) |
| #else |
| #error "wut? Unknown __BYTE_ORDER?!" |
| #endif |
| |
| #define SIBLING_EXIT_UNKILLED 0xbadbeef |
| #define SIBLING_EXIT_FAILURE 0xbadface |
| #define SIBLING_EXIT_NEWPRIVS 0xbadfeed |
| |
| TEST(mode_strict_support) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Kernel does not support CONFIG_SECCOMP"); |
| } |
| syscall(__NR_exit, 1); |
| } |
| |
| TEST_SIGNAL(mode_strict_cannot_call_prctl, SIGKILL) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Kernel does not support CONFIG_SECCOMP"); |
| } |
| syscall(__NR_prctl, PR_SET_SECCOMP, SECCOMP_MODE_FILTER, |
| NULL, NULL, NULL); |
| EXPECT_FALSE(true) { |
| TH_LOG("Unreachable!"); |
| } |
| } |
| |
| /* Note! This doesn't test no new privs behavior */ |
| TEST(no_new_privs_support) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| EXPECT_EQ(0, ret) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| } |
| |
| /* Tests kernel support by checking for a copy_from_user() fault on * NULL. */ |
| TEST(mode_filter_support) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, NULL, NULL); |
| EXPECT_EQ(-1, ret); |
| EXPECT_EQ(EFAULT, errno) { |
| TH_LOG("Kernel does not support CONFIG_SECCOMP_FILTER!"); |
| } |
| } |
| |
| TEST(mode_filter_without_nnp) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_GET_NO_NEW_PRIVS, 0, NULL, 0, 0); |
| ASSERT_LE(0, ret) { |
| TH_LOG("Expected 0 or unsupported for NO_NEW_PRIVS"); |
| } |
| errno = 0; |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0); |
| /* Succeeds with CAP_SYS_ADMIN, fails without */ |
| /* TODO(wad) check caps not euid */ |
| if (geteuid()) { |
| EXPECT_EQ(-1, ret); |
| EXPECT_EQ(EACCES, errno); |
| } else { |
| EXPECT_EQ(0, ret); |
| } |
| } |
| |
| #define MAX_INSNS_PER_PATH 32768 |
| |
| TEST(filter_size_limits) |
| { |
| int i; |
| int count = BPF_MAXINSNS + 1; |
| struct sock_filter allow[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_filter *filter; |
| struct sock_fprog prog = { }; |
| long ret; |
| |
| filter = calloc(count, sizeof(*filter)); |
| ASSERT_NE(NULL, filter); |
| |
| for (i = 0; i < count; i++) |
| filter[i] = allow[0]; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| prog.filter = filter; |
| prog.len = count; |
| |
| /* Too many filter instructions in a single filter. */ |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0); |
| ASSERT_NE(0, ret) { |
| TH_LOG("Installing %d insn filter was allowed", prog.len); |
| } |
| |
| /* One less is okay, though. */ |
| prog.len -= 1; |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Installing %d insn filter wasn't allowed", prog.len); |
| } |
| } |
| |
| TEST(filter_chain_limits) |
| { |
| int i; |
| int count = BPF_MAXINSNS; |
| struct sock_filter allow[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_filter *filter; |
| struct sock_fprog prog = { }; |
| long ret; |
| |
| filter = calloc(count, sizeof(*filter)); |
| ASSERT_NE(NULL, filter); |
| |
| for (i = 0; i < count; i++) |
| filter[i] = allow[0]; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| prog.filter = filter; |
| prog.len = 1; |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| prog.len = count; |
| |
| /* Too many total filter instructions. */ |
| for (i = 0; i < MAX_INSNS_PER_PATH; i++) { |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0); |
| if (ret != 0) |
| break; |
| } |
| ASSERT_NE(0, ret) { |
| TH_LOG("Allowed %d %d-insn filters (total with penalties:%d)", |
| i, count, i * (count + 4)); |
| } |
| } |
| |
| TEST(mode_filter_cannot_move_to_strict) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, 0, 0); |
| EXPECT_EQ(-1, ret); |
| EXPECT_EQ(EINVAL, errno); |
| } |
| |
| |
| TEST(mode_filter_get_seccomp) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0); |
| EXPECT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0); |
| EXPECT_EQ(2, ret); |
| } |
| |
| |
| TEST(ALLOW_all) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| } |
| |
| TEST(empty_prog) |
| { |
| struct sock_filter filter[] = { |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| EXPECT_EQ(-1, ret); |
| EXPECT_EQ(EINVAL, errno); |
| } |
| |
| TEST_SIGNAL(unknown_ret_is_kill_inside, SIGSYS) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, 0x10000000U), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| EXPECT_EQ(0, syscall(__NR_getpid)) { |
| TH_LOG("getpid() shouldn't ever return"); |
| } |
| } |
| |
| /* return code >= 0x80000000 is unused. */ |
| TEST_SIGNAL(unknown_ret_is_kill_above_allow, SIGSYS) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, 0x90000000U), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| EXPECT_EQ(0, syscall(__NR_getpid)) { |
| TH_LOG("getpid() shouldn't ever return"); |
| } |
| } |
| |
| TEST_SIGNAL(KILL_all, SIGSYS) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| } |
| |
| TEST_SIGNAL(KILL_one, SIGSYS) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| pid_t parent = getppid(); |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| /* getpid() should never return. */ |
| EXPECT_EQ(0, syscall(__NR_getpid)); |
| } |
| |
| TEST_SIGNAL(KILL_one_arg_one, SIGSYS) |
| { |
| void *fatal_address; |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_times, 1, 0), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| /* Only both with lower 32-bit for now. */ |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(0)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, |
| (unsigned long)&fatal_address, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| pid_t parent = getppid(); |
| struct tms timebuf; |
| clock_t clock = times(&timebuf); |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| EXPECT_LE(clock, syscall(__NR_times, &timebuf)); |
| /* times() should never return. */ |
| EXPECT_EQ(0, syscall(__NR_times, &fatal_address)); |
| } |
| |
| TEST_SIGNAL(KILL_one_arg_six, SIGSYS) |
| { |
| #ifndef __NR_mmap2 |
| int sysno = __NR_mmap; |
| #else |
| int sysno = __NR_mmap2; |
| #endif |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, sysno, 1, 0), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| /* Only both with lower 32-bit for now. */ |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(5)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x0C0FFEE, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| pid_t parent = getppid(); |
| int fd; |
| void *map1, *map2; |
| int page_size = sysconf(_SC_PAGESIZE); |
| |
| ASSERT_LT(0, page_size); |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| |
| fd = open("/dev/zero", O_RDONLY); |
| ASSERT_NE(-1, fd); |
| |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| map1 = (void *)syscall(sysno, |
| NULL, page_size, PROT_READ, MAP_PRIVATE, fd, page_size); |
| EXPECT_NE(MAP_FAILED, map1); |
| /* mmap2() should never return. */ |
| map2 = (void *)syscall(sysno, |
| NULL, page_size, PROT_READ, MAP_PRIVATE, fd, 0x0C0FFEE); |
| EXPECT_EQ(MAP_FAILED, map2); |
| |
| /* The test failed, so clean up the resources. */ |
| munmap(map1, page_size); |
| munmap(map2, page_size); |
| close(fd); |
| } |
| |
| /* TODO(wad) add 64-bit versus 32-bit arg tests. */ |
| TEST(arg_out_of_range) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(6)), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| EXPECT_EQ(-1, ret); |
| EXPECT_EQ(EINVAL, errno); |
| } |
| |
| TEST(ERRNO_valid) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | E2BIG), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| pid_t parent = getppid(); |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| EXPECT_EQ(-1, read(0, NULL, 0)); |
| EXPECT_EQ(E2BIG, errno); |
| } |
| |
| TEST(ERRNO_zero) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | 0), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| pid_t parent = getppid(); |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| /* "errno" of 0 is ok. */ |
| EXPECT_EQ(0, read(0, NULL, 0)); |
| } |
| |
| TEST(ERRNO_capped) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | 4096), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| pid_t parent = getppid(); |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog); |
| ASSERT_EQ(0, ret); |
| |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| EXPECT_EQ(-1, read(0, NULL, 0)); |
| EXPECT_EQ(4095, errno); |
| } |
| |
| FIXTURE_DATA(TRAP) { |
| struct sock_fprog prog; |
| }; |
| |
| FIXTURE_SETUP(TRAP) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| |
| memset(&self->prog, 0, sizeof(self->prog)); |
| self->prog.filter = malloc(sizeof(filter)); |
| ASSERT_NE(NULL, self->prog.filter); |
| memcpy(self->prog.filter, filter, sizeof(filter)); |
| self->prog.len = (unsigned short)ARRAY_SIZE(filter); |
| } |
| |
| FIXTURE_TEARDOWN(TRAP) |
| { |
| if (self->prog.filter) |
| free(self->prog.filter); |
| } |
| |
| TEST_F_SIGNAL(TRAP, dfl, SIGSYS) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog); |
| ASSERT_EQ(0, ret); |
| syscall(__NR_getpid); |
| } |
| |
| /* Ensure that SIGSYS overrides SIG_IGN */ |
| TEST_F_SIGNAL(TRAP, ign, SIGSYS) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| signal(SIGSYS, SIG_IGN); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog); |
| ASSERT_EQ(0, ret); |
| syscall(__NR_getpid); |
| } |
| |
| static struct siginfo TRAP_info; |
| static volatile int TRAP_nr; |
| static void TRAP_action(int nr, siginfo_t *info, void *void_context) |
| { |
| memcpy(&TRAP_info, info, sizeof(TRAP_info)); |
| TRAP_nr = nr; |
| } |
| |
| TEST_F(TRAP, handler) |
| { |
| int ret, test; |
| struct sigaction act; |
| sigset_t mask; |
| |
| memset(&act, 0, sizeof(act)); |
| sigemptyset(&mask); |
| sigaddset(&mask, SIGSYS); |
| |
| act.sa_sigaction = &TRAP_action; |
| act.sa_flags = SA_SIGINFO; |
| ret = sigaction(SIGSYS, &act, NULL); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("sigaction failed"); |
| } |
| ret = sigprocmask(SIG_UNBLOCK, &mask, NULL); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("sigprocmask failed"); |
| } |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog); |
| ASSERT_EQ(0, ret); |
| TRAP_nr = 0; |
| memset(&TRAP_info, 0, sizeof(TRAP_info)); |
| /* Expect the registers to be rolled back. (nr = error) may vary |
| * based on arch. */ |
| ret = syscall(__NR_getpid); |
| /* Silence gcc warning about volatile. */ |
| test = TRAP_nr; |
| EXPECT_EQ(SIGSYS, test); |
| struct local_sigsys { |
| void *_call_addr; /* calling user insn */ |
| int _syscall; /* triggering system call number */ |
| unsigned int _arch; /* AUDIT_ARCH_* of syscall */ |
| } *sigsys = (struct local_sigsys *) |
| #ifdef si_syscall |
| &(TRAP_info.si_call_addr); |
| #else |
| &TRAP_info.si_pid; |
| #endif |
| EXPECT_EQ(__NR_getpid, sigsys->_syscall); |
| /* Make sure arch is non-zero. */ |
| EXPECT_NE(0, sigsys->_arch); |
| EXPECT_NE(0, (unsigned long)sigsys->_call_addr); |
| } |
| |
| FIXTURE_DATA(precedence) { |
| struct sock_fprog allow; |
| struct sock_fprog trace; |
| struct sock_fprog error; |
| struct sock_fprog trap; |
| struct sock_fprog kill; |
| }; |
| |
| FIXTURE_SETUP(precedence) |
| { |
| struct sock_filter allow_insns[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_filter trace_insns[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE), |
| }; |
| struct sock_filter error_insns[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO), |
| }; |
| struct sock_filter trap_insns[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP), |
| }; |
| struct sock_filter kill_insns[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL), |
| }; |
| |
| memset(self, 0, sizeof(*self)); |
| #define FILTER_ALLOC(_x) \ |
| self->_x.filter = malloc(sizeof(_x##_insns)); \ |
| ASSERT_NE(NULL, self->_x.filter); \ |
| memcpy(self->_x.filter, &_x##_insns, sizeof(_x##_insns)); \ |
| self->_x.len = (unsigned short)ARRAY_SIZE(_x##_insns) |
| FILTER_ALLOC(allow); |
| FILTER_ALLOC(trace); |
| FILTER_ALLOC(error); |
| FILTER_ALLOC(trap); |
| FILTER_ALLOC(kill); |
| } |
| |
| FIXTURE_TEARDOWN(precedence) |
| { |
| #define FILTER_FREE(_x) if (self->_x.filter) free(self->_x.filter) |
| FILTER_FREE(allow); |
| FILTER_FREE(trace); |
| FILTER_FREE(error); |
| FILTER_FREE(trap); |
| FILTER_FREE(kill); |
| } |
| |
| TEST_F(precedence, allow_ok) |
| { |
| pid_t parent, res = 0; |
| long ret; |
| |
| parent = getppid(); |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill); |
| ASSERT_EQ(0, ret); |
| /* Should work just fine. */ |
| res = syscall(__NR_getppid); |
| EXPECT_EQ(parent, res); |
| } |
| |
| TEST_F_SIGNAL(precedence, kill_is_highest, SIGSYS) |
| { |
| pid_t parent, res = 0; |
| long ret; |
| |
| parent = getppid(); |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill); |
| ASSERT_EQ(0, ret); |
| /* Should work just fine. */ |
| res = syscall(__NR_getppid); |
| EXPECT_EQ(parent, res); |
| /* getpid() should never return. */ |
| res = syscall(__NR_getpid); |
| EXPECT_EQ(0, res); |
| } |
| |
| TEST_F_SIGNAL(precedence, kill_is_highest_in_any_order, SIGSYS) |
| { |
| pid_t parent; |
| long ret; |
| |
| parent = getppid(); |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap); |
| ASSERT_EQ(0, ret); |
| /* Should work just fine. */ |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| /* getpid() should never return. */ |
| EXPECT_EQ(0, syscall(__NR_getpid)); |
| } |
| |
| TEST_F_SIGNAL(precedence, trap_is_second, SIGSYS) |
| { |
| pid_t parent; |
| long ret; |
| |
| parent = getppid(); |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap); |
| ASSERT_EQ(0, ret); |
| /* Should work just fine. */ |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| /* getpid() should never return. */ |
| EXPECT_EQ(0, syscall(__NR_getpid)); |
| } |
| |
| TEST_F_SIGNAL(precedence, trap_is_second_in_any_order, SIGSYS) |
| { |
| pid_t parent; |
| long ret; |
| |
| parent = getppid(); |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error); |
| ASSERT_EQ(0, ret); |
| /* Should work just fine. */ |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| /* getpid() should never return. */ |
| EXPECT_EQ(0, syscall(__NR_getpid)); |
| } |
| |
| TEST_F(precedence, errno_is_third) |
| { |
| pid_t parent; |
| long ret; |
| |
| parent = getppid(); |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error); |
| ASSERT_EQ(0, ret); |
| /* Should work just fine. */ |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| EXPECT_EQ(0, syscall(__NR_getpid)); |
| } |
| |
| TEST_F(precedence, errno_is_third_in_any_order) |
| { |
| pid_t parent; |
| long ret; |
| |
| parent = getppid(); |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow); |
| ASSERT_EQ(0, ret); |
| /* Should work just fine. */ |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| EXPECT_EQ(0, syscall(__NR_getpid)); |
| } |
| |
| TEST_F(precedence, trace_is_fourth) |
| { |
| pid_t parent; |
| long ret; |
| |
| parent = getppid(); |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace); |
| ASSERT_EQ(0, ret); |
| /* Should work just fine. */ |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| /* No ptracer */ |
| EXPECT_EQ(-1, syscall(__NR_getpid)); |
| } |
| |
| TEST_F(precedence, trace_is_fourth_in_any_order) |
| { |
| pid_t parent; |
| long ret; |
| |
| parent = getppid(); |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace); |
| ASSERT_EQ(0, ret); |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow); |
| ASSERT_EQ(0, ret); |
| /* Should work just fine. */ |
| EXPECT_EQ(parent, syscall(__NR_getppid)); |
| /* No ptracer */ |
| EXPECT_EQ(-1, syscall(__NR_getpid)); |
| } |
| |
| #ifndef PTRACE_O_TRACESECCOMP |
| #define PTRACE_O_TRACESECCOMP 0x00000080 |
| #endif |
| |
| /* Catch the Ubuntu 12.04 value error. */ |
| #if PTRACE_EVENT_SECCOMP != 7 |
| #undef PTRACE_EVENT_SECCOMP |
| #endif |
| |
| #ifndef PTRACE_EVENT_SECCOMP |
| #define PTRACE_EVENT_SECCOMP 7 |
| #endif |
| |
| #define IS_SECCOMP_EVENT(status) ((status >> 16) == PTRACE_EVENT_SECCOMP) |
| bool tracer_running; |
| void tracer_stop(int sig) |
| { |
| tracer_running = false; |
| } |
| |
| typedef void tracer_func_t(struct __test_metadata *_metadata, |
| pid_t tracee, int status, void *args); |
| |
| void tracer(struct __test_metadata *_metadata, int fd, pid_t tracee, |
| tracer_func_t tracer_func, void *args) |
| { |
| int ret = -1; |
| struct sigaction action = { |
| .sa_handler = tracer_stop, |
| }; |
| |
| /* Allow external shutdown. */ |
| tracer_running = true; |
| ASSERT_EQ(0, sigaction(SIGUSR1, &action, NULL)); |
| |
| errno = 0; |
| while (ret == -1 && errno != EINVAL) |
| ret = ptrace(PTRACE_ATTACH, tracee, NULL, 0); |
| ASSERT_EQ(0, ret) { |
| kill(tracee, SIGKILL); |
| } |
| /* Wait for attach stop */ |
| wait(NULL); |
| |
| ret = ptrace(PTRACE_SETOPTIONS, tracee, NULL, PTRACE_O_TRACESECCOMP); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Failed to set PTRACE_O_TRACESECCOMP"); |
| kill(tracee, SIGKILL); |
| } |
| ptrace(PTRACE_CONT, tracee, NULL, 0); |
| |
| /* Unblock the tracee */ |
| ASSERT_EQ(1, write(fd, "A", 1)); |
| ASSERT_EQ(0, close(fd)); |
| |
| /* Run until we're shut down. Must assert to stop execution. */ |
| while (tracer_running) { |
| int status; |
| |
| if (wait(&status) != tracee) |
| continue; |
| if (WIFSIGNALED(status) || WIFEXITED(status)) |
| /* Child is dead. Time to go. */ |
| return; |
| |
| /* Make sure this is a seccomp event. */ |
| ASSERT_EQ(true, IS_SECCOMP_EVENT(status)); |
| |
| tracer_func(_metadata, tracee, status, args); |
| |
| ret = ptrace(PTRACE_CONT, tracee, NULL, NULL); |
| ASSERT_EQ(0, ret); |
| } |
| /* Directly report the status of our test harness results. */ |
| syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE); |
| } |
| |
| /* Common tracer setup/teardown functions. */ |
| void cont_handler(int num) |
| { } |
| pid_t setup_trace_fixture(struct __test_metadata *_metadata, |
| tracer_func_t func, void *args) |
| { |
| char sync; |
| int pipefd[2]; |
| pid_t tracer_pid; |
| pid_t tracee = getpid(); |
| |
| /* Setup a pipe for clean synchronization. */ |
| ASSERT_EQ(0, pipe(pipefd)); |
| |
| /* Fork a child which we'll promote to tracer */ |
| tracer_pid = fork(); |
| ASSERT_LE(0, tracer_pid); |
| signal(SIGALRM, cont_handler); |
| if (tracer_pid == 0) { |
| close(pipefd[0]); |
| tracer(_metadata, pipefd[1], tracee, func, args); |
| syscall(__NR_exit, 0); |
| } |
| close(pipefd[1]); |
| prctl(PR_SET_PTRACER, tracer_pid, 0, 0, 0); |
| read(pipefd[0], &sync, 1); |
| close(pipefd[0]); |
| |
| return tracer_pid; |
| } |
| void teardown_trace_fixture(struct __test_metadata *_metadata, |
| pid_t tracer) |
| { |
| if (tracer) { |
| int status; |
| /* |
| * Extract the exit code from the other process and |
| * adopt it for ourselves in case its asserts failed. |
| */ |
| ASSERT_EQ(0, kill(tracer, SIGUSR1)); |
| ASSERT_EQ(tracer, waitpid(tracer, &status, 0)); |
| if (WEXITSTATUS(status)) |
| _metadata->passed = 0; |
| } |
| } |
| |
| /* "poke" tracer arguments and function. */ |
| struct tracer_args_poke_t { |
| unsigned long poke_addr; |
| }; |
| |
| void tracer_poke(struct __test_metadata *_metadata, pid_t tracee, int status, |
| void *args) |
| { |
| int ret; |
| unsigned long msg; |
| struct tracer_args_poke_t *info = (struct tracer_args_poke_t *)args; |
| |
| ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg); |
| EXPECT_EQ(0, ret); |
| /* If this fails, don't try to recover. */ |
| ASSERT_EQ(0x1001, msg) { |
| kill(tracee, SIGKILL); |
| } |
| /* |
| * Poke in the message. |
| * Registers are not touched to try to keep this relatively arch |
| * agnostic. |
| */ |
| ret = ptrace(PTRACE_POKEDATA, tracee, info->poke_addr, 0x1001); |
| EXPECT_EQ(0, ret); |
| } |
| |
| FIXTURE_DATA(TRACE_poke) { |
| struct sock_fprog prog; |
| pid_t tracer; |
| long poked; |
| struct tracer_args_poke_t tracer_args; |
| }; |
| |
| FIXTURE_SETUP(TRACE_poke) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1001), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| |
| self->poked = 0; |
| memset(&self->prog, 0, sizeof(self->prog)); |
| self->prog.filter = malloc(sizeof(filter)); |
| ASSERT_NE(NULL, self->prog.filter); |
| memcpy(self->prog.filter, filter, sizeof(filter)); |
| self->prog.len = (unsigned short)ARRAY_SIZE(filter); |
| |
| /* Set up tracer args. */ |
| self->tracer_args.poke_addr = (unsigned long)&self->poked; |
| |
| /* Launch tracer. */ |
| self->tracer = setup_trace_fixture(_metadata, tracer_poke, |
| &self->tracer_args); |
| } |
| |
| FIXTURE_TEARDOWN(TRACE_poke) |
| { |
| teardown_trace_fixture(_metadata, self->tracer); |
| if (self->prog.filter) |
| free(self->prog.filter); |
| } |
| |
| TEST_F(TRACE_poke, read_has_side_effects) |
| { |
| ssize_t ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| EXPECT_EQ(0, self->poked); |
| ret = read(-1, NULL, 0); |
| EXPECT_EQ(-1, ret); |
| EXPECT_EQ(0x1001, self->poked); |
| } |
| |
| TEST_F(TRACE_poke, getpid_runs_normally) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| EXPECT_EQ(0, self->poked); |
| EXPECT_NE(0, syscall(__NR_getpid)); |
| EXPECT_EQ(0, self->poked); |
| } |
| |
| #if defined(__x86_64__) |
| # define ARCH_REGS struct user_regs_struct |
| # define SYSCALL_NUM orig_rax |
| # define SYSCALL_RET rax |
| #elif defined(__i386__) |
| # define ARCH_REGS struct user_regs_struct |
| # define SYSCALL_NUM orig_eax |
| # define SYSCALL_RET eax |
| #elif defined(__arm__) |
| # define ARCH_REGS struct pt_regs |
| # define SYSCALL_NUM ARM_r7 |
| # define SYSCALL_RET ARM_r0 |
| #elif defined(__aarch64__) |
| # define ARCH_REGS struct user_pt_regs |
| # define SYSCALL_NUM regs[8] |
| # define SYSCALL_RET regs[0] |
| #elif defined(__powerpc__) |
| # define ARCH_REGS struct pt_regs |
| # define SYSCALL_NUM gpr[0] |
| # define SYSCALL_RET gpr[3] |
| #elif defined(__s390__) |
| # define ARCH_REGS s390_regs |
| # define SYSCALL_NUM gprs[2] |
| # define SYSCALL_RET gprs[2] |
| #else |
| # error "Do not know how to find your architecture's registers and syscalls" |
| #endif |
| |
| /* Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for |
| * architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux). |
| */ |
| #if defined(__x86_64__) || defined(__i386__) |
| #define HAVE_GETREGS |
| #endif |
| |
| /* Architecture-specific syscall fetching routine. */ |
| int get_syscall(struct __test_metadata *_metadata, pid_t tracee) |
| { |
| ARCH_REGS regs; |
| #ifdef HAVE_GETREGS |
| EXPECT_EQ(0, ptrace(PTRACE_GETREGS, tracee, 0, ®s)) { |
| TH_LOG("PTRACE_GETREGS failed"); |
| return -1; |
| } |
| #else |
| struct iovec iov; |
| |
| iov.iov_base = ®s; |
| iov.iov_len = sizeof(regs); |
| EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) { |
| TH_LOG("PTRACE_GETREGSET failed"); |
| return -1; |
| } |
| #endif |
| |
| return regs.SYSCALL_NUM; |
| } |
| |
| /* Architecture-specific syscall changing routine. */ |
| void change_syscall(struct __test_metadata *_metadata, |
| pid_t tracee, int syscall) |
| { |
| int ret; |
| ARCH_REGS regs; |
| #ifdef HAVE_GETREGS |
| ret = ptrace(PTRACE_GETREGS, tracee, 0, ®s); |
| #else |
| struct iovec iov; |
| iov.iov_base = ®s; |
| iov.iov_len = sizeof(regs); |
| ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov); |
| #endif |
| EXPECT_EQ(0, ret); |
| |
| #if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \ |
| defined(__s390__) |
| { |
| regs.SYSCALL_NUM = syscall; |
| } |
| |
| #elif defined(__arm__) |
| # ifndef PTRACE_SET_SYSCALL |
| # define PTRACE_SET_SYSCALL 23 |
| # endif |
| { |
| ret = ptrace(PTRACE_SET_SYSCALL, tracee, NULL, syscall); |
| EXPECT_EQ(0, ret); |
| } |
| |
| #elif defined(__aarch64__) |
| # ifndef NT_ARM_SYSTEM_CALL |
| # define NT_ARM_SYSTEM_CALL 0x404 |
| # endif |
| { |
| iov.iov_base = &syscall; |
| iov.iov_len = sizeof(syscall); |
| ret = ptrace(PTRACE_SETREGSET, tracee, NT_ARM_SYSTEM_CALL, |
| &iov); |
| EXPECT_EQ(0, ret); |
| } |
| |
| #else |
| ASSERT_EQ(1, 0) { |
| TH_LOG("How is the syscall changed on this architecture?"); |
| } |
| #endif |
| |
| /* If syscall is skipped, change return value. */ |
| if (syscall == -1) |
| regs.SYSCALL_RET = 1; |
| |
| #ifdef HAVE_GETREGS |
| ret = ptrace(PTRACE_SETREGS, tracee, 0, ®s); |
| #else |
| iov.iov_base = ®s; |
| iov.iov_len = sizeof(regs); |
| ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov); |
| #endif |
| EXPECT_EQ(0, ret); |
| } |
| |
| void tracer_syscall(struct __test_metadata *_metadata, pid_t tracee, |
| int status, void *args) |
| { |
| int ret; |
| unsigned long msg; |
| |
| /* Make sure we got the right message. */ |
| ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg); |
| EXPECT_EQ(0, ret); |
| |
| /* Validate and take action on expected syscalls. */ |
| switch (msg) { |
| case 0x1002: |
| /* change getpid to getppid. */ |
| EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee)); |
| change_syscall(_metadata, tracee, __NR_getppid); |
| break; |
| case 0x1003: |
| /* skip gettid. */ |
| EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee)); |
| change_syscall(_metadata, tracee, -1); |
| break; |
| case 0x1004: |
| /* do nothing (allow getppid) */ |
| EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee)); |
| break; |
| default: |
| EXPECT_EQ(0, msg) { |
| TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg); |
| kill(tracee, SIGKILL); |
| } |
| } |
| |
| } |
| |
| FIXTURE_DATA(TRACE_syscall) { |
| struct sock_fprog prog; |
| pid_t tracer, mytid, mypid, parent; |
| }; |
| |
| FIXTURE_SETUP(TRACE_syscall) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| |
| memset(&self->prog, 0, sizeof(self->prog)); |
| self->prog.filter = malloc(sizeof(filter)); |
| ASSERT_NE(NULL, self->prog.filter); |
| memcpy(self->prog.filter, filter, sizeof(filter)); |
| self->prog.len = (unsigned short)ARRAY_SIZE(filter); |
| |
| /* Prepare some testable syscall results. */ |
| self->mytid = syscall(__NR_gettid); |
| ASSERT_GT(self->mytid, 0); |
| ASSERT_NE(self->mytid, 1) { |
| TH_LOG("Running this test as init is not supported. :)"); |
| } |
| |
| self->mypid = getpid(); |
| ASSERT_GT(self->mypid, 0); |
| ASSERT_EQ(self->mytid, self->mypid); |
| |
| self->parent = getppid(); |
| ASSERT_GT(self->parent, 0); |
| ASSERT_NE(self->parent, self->mypid); |
| |
| /* Launch tracer. */ |
| self->tracer = setup_trace_fixture(_metadata, tracer_syscall, NULL); |
| } |
| |
| FIXTURE_TEARDOWN(TRACE_syscall) |
| { |
| teardown_trace_fixture(_metadata, self->tracer); |
| if (self->prog.filter) |
| free(self->prog.filter); |
| } |
| |
| TEST_F(TRACE_syscall, syscall_allowed) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| /* getppid works as expected (no changes). */ |
| EXPECT_EQ(self->parent, syscall(__NR_getppid)); |
| EXPECT_NE(self->mypid, syscall(__NR_getppid)); |
| } |
| |
| TEST_F(TRACE_syscall, syscall_redirected) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| /* getpid has been redirected to getppid as expected. */ |
| EXPECT_EQ(self->parent, syscall(__NR_getpid)); |
| EXPECT_NE(self->mypid, syscall(__NR_getpid)); |
| } |
| |
| TEST_F(TRACE_syscall, syscall_dropped) |
| { |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0); |
| ASSERT_EQ(0, ret); |
| |
| /* gettid has been skipped and an altered return value stored. */ |
| EXPECT_EQ(1, syscall(__NR_gettid)); |
| EXPECT_NE(self->mytid, syscall(__NR_gettid)); |
| } |
| |
| #ifndef __NR_seccomp |
| # if defined(__i386__) |
| # define __NR_seccomp 354 |
| # elif defined(__x86_64__) |
| # define __NR_seccomp 317 |
| # elif defined(__arm__) |
| # define __NR_seccomp 383 |
| # elif defined(__aarch64__) |
| # define __NR_seccomp 277 |
| # elif defined(__powerpc__) |
| # define __NR_seccomp 358 |
| # elif defined(__s390__) |
| # define __NR_seccomp 348 |
| # else |
| # warning "seccomp syscall number unknown for this architecture" |
| # define __NR_seccomp 0xffff |
| # endif |
| #endif |
| |
| #ifndef SECCOMP_SET_MODE_STRICT |
| #define SECCOMP_SET_MODE_STRICT 0 |
| #endif |
| |
| #ifndef SECCOMP_SET_MODE_FILTER |
| #define SECCOMP_SET_MODE_FILTER 1 |
| #endif |
| |
| #ifndef SECCOMP_FILTER_FLAG_TSYNC |
| #define SECCOMP_FILTER_FLAG_TSYNC 1 |
| #endif |
| |
| #ifndef seccomp |
| int seccomp(unsigned int op, unsigned int flags, void *args) |
| { |
| errno = 0; |
| return syscall(__NR_seccomp, op, flags, args); |
| } |
| #endif |
| |
| TEST(seccomp_syscall) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| |
| /* Reject insane operation. */ |
| ret = seccomp(-1, 0, &prog); |
| ASSERT_NE(ENOSYS, errno) { |
| TH_LOG("Kernel does not support seccomp syscall!"); |
| } |
| EXPECT_EQ(EINVAL, errno) { |
| TH_LOG("Did not reject crazy op value!"); |
| } |
| |
| /* Reject strict with flags or pointer. */ |
| ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL); |
| EXPECT_EQ(EINVAL, errno) { |
| TH_LOG("Did not reject mode strict with flags!"); |
| } |
| ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog); |
| EXPECT_EQ(EINVAL, errno) { |
| TH_LOG("Did not reject mode strict with uargs!"); |
| } |
| |
| /* Reject insane args for filter. */ |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog); |
| EXPECT_EQ(EINVAL, errno) { |
| TH_LOG("Did not reject crazy filter flags!"); |
| } |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL); |
| EXPECT_EQ(EFAULT, errno) { |
| TH_LOG("Did not reject NULL filter!"); |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog); |
| EXPECT_EQ(0, errno) { |
| TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s", |
| strerror(errno)); |
| } |
| } |
| |
| TEST(seccomp_syscall_mode_lock) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog); |
| ASSERT_NE(ENOSYS, errno) { |
| TH_LOG("Kernel does not support seccomp syscall!"); |
| } |
| EXPECT_EQ(0, ret) { |
| TH_LOG("Could not install filter!"); |
| } |
| |
| /* Make sure neither entry point will switch to strict. */ |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0); |
| EXPECT_EQ(EINVAL, errno) { |
| TH_LOG("Switched to mode strict!"); |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL); |
| EXPECT_EQ(EINVAL, errno) { |
| TH_LOG("Switched to mode strict!"); |
| } |
| } |
| |
| TEST(TSYNC_first) |
| { |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| long ret; |
| |
| ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC, |
| &prog); |
| ASSERT_NE(ENOSYS, errno) { |
| TH_LOG("Kernel does not support seccomp syscall!"); |
| } |
| EXPECT_EQ(0, ret) { |
| TH_LOG("Could not install initial filter with TSYNC!"); |
| } |
| } |
| |
| #define TSYNC_SIBLINGS 2 |
| struct tsync_sibling { |
| pthread_t tid; |
| pid_t system_tid; |
| sem_t *started; |
| pthread_cond_t *cond; |
| pthread_mutex_t *mutex; |
| int diverge; |
| int num_waits; |
| struct sock_fprog *prog; |
| struct __test_metadata *metadata; |
| }; |
| |
| FIXTURE_DATA(TSYNC) { |
| struct sock_fprog root_prog, apply_prog; |
| struct tsync_sibling sibling[TSYNC_SIBLINGS]; |
| sem_t started; |
| pthread_cond_t cond; |
| pthread_mutex_t mutex; |
| int sibling_count; |
| }; |
| |
| FIXTURE_SETUP(TSYNC) |
| { |
| struct sock_filter root_filter[] = { |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_filter apply_filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| |
| memset(&self->root_prog, 0, sizeof(self->root_prog)); |
| memset(&self->apply_prog, 0, sizeof(self->apply_prog)); |
| memset(&self->sibling, 0, sizeof(self->sibling)); |
| self->root_prog.filter = malloc(sizeof(root_filter)); |
| ASSERT_NE(NULL, self->root_prog.filter); |
| memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter)); |
| self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter); |
| |
| self->apply_prog.filter = malloc(sizeof(apply_filter)); |
| ASSERT_NE(NULL, self->apply_prog.filter); |
| memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter)); |
| self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter); |
| |
| self->sibling_count = 0; |
| pthread_mutex_init(&self->mutex, NULL); |
| pthread_cond_init(&self->cond, NULL); |
| sem_init(&self->started, 0, 0); |
| self->sibling[0].tid = 0; |
| self->sibling[0].cond = &self->cond; |
| self->sibling[0].started = &self->started; |
| self->sibling[0].mutex = &self->mutex; |
| self->sibling[0].diverge = 0; |
| self->sibling[0].num_waits = 1; |
| self->sibling[0].prog = &self->root_prog; |
| self->sibling[0].metadata = _metadata; |
| self->sibling[1].tid = 0; |
| self->sibling[1].cond = &self->cond; |
| self->sibling[1].started = &self->started; |
| self->sibling[1].mutex = &self->mutex; |
| self->sibling[1].diverge = 0; |
| self->sibling[1].prog = &self->root_prog; |
| self->sibling[1].num_waits = 1; |
| self->sibling[1].metadata = _metadata; |
| } |
| |
| FIXTURE_TEARDOWN(TSYNC) |
| { |
| int sib = 0; |
| |
| if (self->root_prog.filter) |
| free(self->root_prog.filter); |
| if (self->apply_prog.filter) |
| free(self->apply_prog.filter); |
| |
| for ( ; sib < self->sibling_count; ++sib) { |
| struct tsync_sibling *s = &self->sibling[sib]; |
| void *status; |
| |
| if (!s->tid) |
| continue; |
| if (pthread_kill(s->tid, 0)) { |
| pthread_cancel(s->tid); |
| pthread_join(s->tid, &status); |
| } |
| } |
| pthread_mutex_destroy(&self->mutex); |
| pthread_cond_destroy(&self->cond); |
| sem_destroy(&self->started); |
| } |
| |
| void *tsync_sibling(void *data) |
| { |
| long ret = 0; |
| struct tsync_sibling *me = data; |
| |
| me->system_tid = syscall(__NR_gettid); |
| |
| pthread_mutex_lock(me->mutex); |
| if (me->diverge) { |
| /* Just re-apply the root prog to fork the tree */ |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, |
| me->prog, 0, 0); |
| } |
| sem_post(me->started); |
| /* Return outside of started so parent notices failures. */ |
| if (ret) { |
| pthread_mutex_unlock(me->mutex); |
| return (void *)SIBLING_EXIT_FAILURE; |
| } |
| do { |
| pthread_cond_wait(me->cond, me->mutex); |
| me->num_waits = me->num_waits - 1; |
| } while (me->num_waits); |
| pthread_mutex_unlock(me->mutex); |
| |
| ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0); |
| if (!ret) |
| return (void *)SIBLING_EXIT_NEWPRIVS; |
| read(0, NULL, 0); |
| return (void *)SIBLING_EXIT_UNKILLED; |
| } |
| |
| void tsync_start_sibling(struct tsync_sibling *sibling) |
| { |
| pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling); |
| } |
| |
| TEST_F(TSYNC, siblings_fail_prctl) |
| { |
| long ret; |
| void *status; |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| |
| ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| |
| /* Check prctl failure detection by requesting sib 0 diverge. */ |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog); |
| ASSERT_NE(ENOSYS, errno) { |
| TH_LOG("Kernel does not support seccomp syscall!"); |
| } |
| ASSERT_EQ(0, ret) { |
| TH_LOG("setting filter failed"); |
| } |
| |
| self->sibling[0].diverge = 1; |
| tsync_start_sibling(&self->sibling[0]); |
| tsync_start_sibling(&self->sibling[1]); |
| |
| while (self->sibling_count < TSYNC_SIBLINGS) { |
| sem_wait(&self->started); |
| self->sibling_count++; |
| } |
| |
| /* Signal the threads to clean up*/ |
| pthread_mutex_lock(&self->mutex); |
| ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) { |
| TH_LOG("cond broadcast non-zero"); |
| } |
| pthread_mutex_unlock(&self->mutex); |
| |
| /* Ensure diverging sibling failed to call prctl. */ |
| pthread_join(self->sibling[0].tid, &status); |
| EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status); |
| pthread_join(self->sibling[1].tid, &status); |
| EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status); |
| } |
| |
| TEST_F(TSYNC, two_siblings_with_ancestor) |
| { |
| long ret; |
| void *status; |
| |
| ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog); |
| ASSERT_NE(ENOSYS, errno) { |
| TH_LOG("Kernel does not support seccomp syscall!"); |
| } |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!"); |
| } |
| tsync_start_sibling(&self->sibling[0]); |
| tsync_start_sibling(&self->sibling[1]); |
| |
| while (self->sibling_count < TSYNC_SIBLINGS) { |
| sem_wait(&self->started); |
| self->sibling_count++; |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC, |
| &self->apply_prog); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Could install filter on all threads!"); |
| } |
| /* Tell the siblings to test the policy */ |
| pthread_mutex_lock(&self->mutex); |
| ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) { |
| TH_LOG("cond broadcast non-zero"); |
| } |
| pthread_mutex_unlock(&self->mutex); |
| /* Ensure they are both killed and don't exit cleanly. */ |
| pthread_join(self->sibling[0].tid, &status); |
| EXPECT_EQ(0x0, (long)status); |
| pthread_join(self->sibling[1].tid, &status); |
| EXPECT_EQ(0x0, (long)status); |
| } |
| |
| TEST_F(TSYNC, two_sibling_want_nnp) |
| { |
| void *status; |
| |
| /* start siblings before any prctl() operations */ |
| tsync_start_sibling(&self->sibling[0]); |
| tsync_start_sibling(&self->sibling[1]); |
| while (self->sibling_count < TSYNC_SIBLINGS) { |
| sem_wait(&self->started); |
| self->sibling_count++; |
| } |
| |
| /* Tell the siblings to test no policy */ |
| pthread_mutex_lock(&self->mutex); |
| ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) { |
| TH_LOG("cond broadcast non-zero"); |
| } |
| pthread_mutex_unlock(&self->mutex); |
| |
| /* Ensure they are both upset about lacking nnp. */ |
| pthread_join(self->sibling[0].tid, &status); |
| EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status); |
| pthread_join(self->sibling[1].tid, &status); |
| EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status); |
| } |
| |
| TEST_F(TSYNC, two_siblings_with_no_filter) |
| { |
| long ret; |
| void *status; |
| |
| /* start siblings before any prctl() operations */ |
| tsync_start_sibling(&self->sibling[0]); |
| tsync_start_sibling(&self->sibling[1]); |
| while (self->sibling_count < TSYNC_SIBLINGS) { |
| sem_wait(&self->started); |
| self->sibling_count++; |
| } |
| |
| ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC, |
| &self->apply_prog); |
| ASSERT_NE(ENOSYS, errno) { |
| TH_LOG("Kernel does not support seccomp syscall!"); |
| } |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Could install filter on all threads!"); |
| } |
| |
| /* Tell the siblings to test the policy */ |
| pthread_mutex_lock(&self->mutex); |
| ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) { |
| TH_LOG("cond broadcast non-zero"); |
| } |
| pthread_mutex_unlock(&self->mutex); |
| |
| /* Ensure they are both killed and don't exit cleanly. */ |
| pthread_join(self->sibling[0].tid, &status); |
| EXPECT_EQ(0x0, (long)status); |
| pthread_join(self->sibling[1].tid, &status); |
| EXPECT_EQ(0x0, (long)status); |
| } |
| |
| TEST_F(TSYNC, two_siblings_with_one_divergence) |
| { |
| long ret; |
| void *status; |
| |
| ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog); |
| ASSERT_NE(ENOSYS, errno) { |
| TH_LOG("Kernel does not support seccomp syscall!"); |
| } |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!"); |
| } |
| self->sibling[0].diverge = 1; |
| tsync_start_sibling(&self->sibling[0]); |
| tsync_start_sibling(&self->sibling[1]); |
| |
| while (self->sibling_count < TSYNC_SIBLINGS) { |
| sem_wait(&self->started); |
| self->sibling_count++; |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC, |
| &self->apply_prog); |
| ASSERT_EQ(self->sibling[0].system_tid, ret) { |
| TH_LOG("Did not fail on diverged sibling."); |
| } |
| |
| /* Wake the threads */ |
| pthread_mutex_lock(&self->mutex); |
| ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) { |
| TH_LOG("cond broadcast non-zero"); |
| } |
| pthread_mutex_unlock(&self->mutex); |
| |
| /* Ensure they are both unkilled. */ |
| pthread_join(self->sibling[0].tid, &status); |
| EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status); |
| pthread_join(self->sibling[1].tid, &status); |
| EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status); |
| } |
| |
| TEST_F(TSYNC, two_siblings_not_under_filter) |
| { |
| long ret, sib; |
| void *status; |
| |
| ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| |
| /* |
| * Sibling 0 will have its own seccomp policy |
| * and Sibling 1 will not be under seccomp at |
| * all. Sibling 1 will enter seccomp and 0 |
| * will cause failure. |
| */ |
| self->sibling[0].diverge = 1; |
| tsync_start_sibling(&self->sibling[0]); |
| tsync_start_sibling(&self->sibling[1]); |
| |
| while (self->sibling_count < TSYNC_SIBLINGS) { |
| sem_wait(&self->started); |
| self->sibling_count++; |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog); |
| ASSERT_NE(ENOSYS, errno) { |
| TH_LOG("Kernel does not support seccomp syscall!"); |
| } |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!"); |
| } |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC, |
| &self->apply_prog); |
| ASSERT_EQ(ret, self->sibling[0].system_tid) { |
| TH_LOG("Did not fail on diverged sibling."); |
| } |
| sib = 1; |
| if (ret == self->sibling[0].system_tid) |
| sib = 0; |
| |
| pthread_mutex_lock(&self->mutex); |
| |
| /* Increment the other siblings num_waits so we can clean up |
| * the one we just saw. |
| */ |
| self->sibling[!sib].num_waits += 1; |
| |
| /* Signal the thread to clean up*/ |
| ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) { |
| TH_LOG("cond broadcast non-zero"); |
| } |
| pthread_mutex_unlock(&self->mutex); |
| pthread_join(self->sibling[sib].tid, &status); |
| EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status); |
| /* Poll for actual task death. pthread_join doesn't guarantee it. */ |
| while (!kill(self->sibling[sib].system_tid, 0)) |
| sleep(0.1); |
| /* Switch to the remaining sibling */ |
| sib = !sib; |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC, |
| &self->apply_prog); |
| ASSERT_EQ(0, ret) { |
| TH_LOG("Expected the remaining sibling to sync"); |
| }; |
| |
| pthread_mutex_lock(&self->mutex); |
| |
| /* If remaining sibling didn't have a chance to wake up during |
| * the first broadcast, manually reduce the num_waits now. |
| */ |
| if (self->sibling[sib].num_waits > 1) |
| self->sibling[sib].num_waits = 1; |
| ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) { |
| TH_LOG("cond broadcast non-zero"); |
| } |
| pthread_mutex_unlock(&self->mutex); |
| pthread_join(self->sibling[sib].tid, &status); |
| EXPECT_EQ(0, (long)status); |
| /* Poll for actual task death. pthread_join doesn't guarantee it. */ |
| while (!kill(self->sibling[sib].system_tid, 0)) |
| sleep(0.1); |
| |
| ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC, |
| &self->apply_prog); |
| ASSERT_EQ(0, ret); /* just us chickens */ |
| } |
| |
| /* Make sure restarted syscalls are seen directly as "restart_syscall". */ |
| TEST(syscall_restart) |
| { |
| long ret; |
| unsigned long msg; |
| pid_t child_pid; |
| int pipefd[2]; |
| int status; |
| siginfo_t info = { }; |
| struct sock_filter filter[] = { |
| BPF_STMT(BPF_LD|BPF_W|BPF_ABS, |
| offsetof(struct seccomp_data, nr)), |
| |
| #ifdef __NR_sigreturn |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 6, 0), |
| #endif |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 5, 0), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 4, 0), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 3, 0), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 4, 0), |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0), |
| |
| /* Allow __NR_write for easy logging. */ |
| BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL), |
| /* The nanosleep jump target. */ |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100), |
| /* The restart_syscall jump target. */ |
| BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200), |
| }; |
| struct sock_fprog prog = { |
| .len = (unsigned short)ARRAY_SIZE(filter), |
| .filter = filter, |
| }; |
| #if defined(__arm__) |
| struct utsname utsbuf; |
| #endif |
| |
| ASSERT_EQ(0, pipe(pipefd)); |
| |
| child_pid = fork(); |
| ASSERT_LE(0, child_pid); |
| if (child_pid == 0) { |
| /* Child uses EXPECT not ASSERT to deliver status correctly. */ |
| char buf = ' '; |
| struct timespec timeout = { }; |
| |
| /* Attach parent as tracer and stop. */ |
| EXPECT_EQ(0, ptrace(PTRACE_TRACEME)); |
| EXPECT_EQ(0, raise(SIGSTOP)); |
| |
| EXPECT_EQ(0, close(pipefd[1])); |
| |
| EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) { |
| TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!"); |
| } |
| |
| ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0); |
| EXPECT_EQ(0, ret) { |
| TH_LOG("Failed to install filter!"); |
| } |
| |
| EXPECT_EQ(1, read(pipefd[0], &buf, 1)) { |
| TH_LOG("Failed to read() sync from parent"); |
| } |
| EXPECT_EQ('.', buf) { |
| TH_LOG("Failed to get sync data from read()"); |
| } |
| |
| /* Start nanosleep to be interrupted. */ |
| timeout.tv_sec = 1; |
| errno = 0; |
| EXPECT_EQ(0, nanosleep(&timeout, NULL)) { |
| TH_LOG("Call to nanosleep() failed (errno %d)", errno); |
| } |
| |
| /* Read final sync from parent. */ |
| EXPECT_EQ(1, read(pipefd[0], &buf, 1)) { |
| TH_LOG("Failed final read() from parent"); |
| } |
| EXPECT_EQ('!', buf) { |
| TH_LOG("Failed to get final data from read()"); |
| } |
| |
| /* Directly report the status of our test harness results. */ |
| syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS |
| : EXIT_FAILURE); |
| } |
| EXPECT_EQ(0, close(pipefd[0])); |
| |
| /* Attach to child, setup options, and release. */ |
| ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0)); |
| ASSERT_EQ(true, WIFSTOPPED(status)); |
| ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL, |
| PTRACE_O_TRACESECCOMP)); |
| ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0)); |
| ASSERT_EQ(1, write(pipefd[1], ".", 1)); |
| |
| /* Wait for nanosleep() to start. */ |
| ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0)); |
| ASSERT_EQ(true, WIFSTOPPED(status)); |
| ASSERT_EQ(SIGTRAP, WSTOPSIG(status)); |
| ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16)); |
| ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg)); |
| ASSERT_EQ(0x100, msg); |
| EXPECT_EQ(__NR_nanosleep, get_syscall(_metadata, child_pid)); |
| |
| /* Might as well check siginfo for sanity while we're here. */ |
| ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info)); |
| ASSERT_EQ(SIGTRAP, info.si_signo); |
| ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code); |
| EXPECT_EQ(0, info.si_errno); |
| EXPECT_EQ(getuid(), info.si_uid); |
| /* Verify signal delivery came from child (seccomp-triggered). */ |
| EXPECT_EQ(child_pid, info.si_pid); |
| |
| /* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */ |
| ASSERT_EQ(0, kill(child_pid, SIGSTOP)); |
| ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0)); |
| ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0)); |
| ASSERT_EQ(true, WIFSTOPPED(status)); |
| ASSERT_EQ(SIGSTOP, WSTOPSIG(status)); |
| /* Verify signal delivery came from parent now. */ |
| ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info)); |
| EXPECT_EQ(getpid(), info.si_pid); |
| |
| /* Restart nanosleep with SIGCONT, which triggers restart_syscall. */ |
| ASSERT_EQ(0, kill(child_pid, SIGCONT)); |
| ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0)); |
| ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0)); |
| ASSERT_EQ(true, WIFSTOPPED(status)); |
| ASSERT_EQ(SIGCONT, WSTOPSIG(status)); |
| ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0)); |
| |
| /* Wait for restart_syscall() to start. */ |
| ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0)); |
| ASSERT_EQ(true, WIFSTOPPED(status)); |
| ASSERT_EQ(SIGTRAP, WSTOPSIG(status)); |
| ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16)); |
| ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg)); |
| |
| ASSERT_EQ(0x200, msg); |
| ret = get_syscall(_metadata, child_pid); |
| #if defined(__arm__) |
| /* |
| * FIXME: |
| * - native ARM registers do NOT expose true syscall. |
| * - compat ARM registers on ARM64 DO expose true syscall. |
| */ |
| ASSERT_EQ(0, uname(&utsbuf)); |
| if (strncmp(utsbuf.machine, "arm", 3) == 0) { |
| EXPECT_EQ(__NR_nanosleep, ret); |
| } else |
| #endif |
| { |
| EXPECT_EQ(__NR_restart_syscall, ret); |
| } |
| |
| /* Write again to end test. */ |
| ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0)); |
| ASSERT_EQ(1, write(pipefd[1], "!", 1)); |
| EXPECT_EQ(0, close(pipefd[1])); |
| |
| ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0)); |
| if (WIFSIGNALED(status) || WEXITSTATUS(status)) |
| _metadata->passed = 0; |
| } |
| |
| /* |
| * TODO: |
| * - add microbenchmarks |
| * - expand NNP testing |
| * - better arch-specific TRACE and TRAP handlers. |
| * - endianness checking when appropriate |
| * - 64-bit arg prodding |
| * - arch value testing (x86 modes especially) |
| * - ... |
| */ |
| |
| TEST_HARNESS_MAIN |