From fd88d16c58c2ad689a68d6790c789e7d5be3fc5b Mon Sep 17 00:00:00 2001 From: Robert Sesek Date: Mon, 2 Nov 2015 15:28:49 -0500 Subject: selftests/seccomp: Be more precise with syscall arguments. Certain syscall emulation layers strictly check that the number of arguments match what the syscall handler expects. The KILL_one_arg_one and KILL_one_arg_six tests passed more parameters than expected to various syscalls, causing failures in this emulation mode. Instead, test using syscalls that take the appropriate number of arguments. Signed-off-by: Robert Sesek Signed-off-by: Kees Cook Signed-off-by: Shuah Khan --- tools/testing/selftests/seccomp/seccomp_bpf.c | 46 ++++++++++++++++++++------- 1 file changed, 35 insertions(+), 11 deletions(-) (limited to 'tools/testing/selftests/seccomp') diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c index e7bc5d3533da..e38cc54942db 100644 --- a/tools/testing/selftests/seccomp/seccomp_bpf.c +++ b/tools/testing/selftests/seccomp/seccomp_bpf.c @@ -29,6 +29,9 @@ #include #include #include +#include +#include +#include #define _GNU_SOURCE #include @@ -429,14 +432,16 @@ TEST_SIGNAL(KILL_one, SIGSYS) 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_getpid, 1, 0), + 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, 0x0C0FFEE, 0, 1), + 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), }; @@ -446,7 +451,8 @@ TEST_SIGNAL(KILL_one_arg_one, SIGSYS) }; long ret; pid_t parent = getppid(); - pid_t pid = getpid(); + struct tms timebuf; + clock_t clock = times(&timebuf); ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); ASSERT_EQ(0, ret); @@ -455,17 +461,22 @@ TEST_SIGNAL(KILL_one_arg_one, SIGSYS) ASSERT_EQ(0, ret); EXPECT_EQ(parent, syscall(__NR_getppid)); - EXPECT_EQ(pid, syscall(__NR_getpid)); - /* getpid() should never return. */ - EXPECT_EQ(0, syscall(__NR_getpid, 0x0C0FFEE)); + 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, __NR_getpid, 1, 0), + 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)), @@ -479,7 +490,8 @@ TEST_SIGNAL(KILL_one_arg_six, SIGSYS) }; long ret; pid_t parent = getppid(); - pid_t pid = getpid(); + int fd; + void *map1, *map2; ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); ASSERT_EQ(0, ret); @@ -487,10 +499,22 @@ TEST_SIGNAL(KILL_one_arg_six, SIGSYS) 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)); - EXPECT_EQ(pid, syscall(__NR_getpid)); - /* getpid() should never return. */ - EXPECT_EQ(0, syscall(__NR_getpid, 1, 2, 3, 4, 5, 0x0C0FFEE)); + 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. */ -- cgit v1.2.3