Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932083AbbKBSw0 (ORCPT ); Mon, 2 Nov 2015 13:52:26 -0500 Received: from mail-qg0-f48.google.com ([209.85.192.48]:35447 "EHLO mail-qg0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752190AbbKBSwX (ORCPT ); Mon, 2 Nov 2015 13:52:23 -0500 From: Robert Sesek To: keescook@chromium.org Cc: linux-kernel@vger.kernel.org, Robert Sesek Subject: [PATCH] selftests/seccomp: Be more precise with syscall arguments. Date: Mon, 2 Nov 2015 13:50:22 -0500 Message-Id: <1446490222-528-1-git-send-email-rsesek@google.com> X-Mailer: git-send-email 2.6.0.rc2.230.g3dd15c0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4170 Lines: 125 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 --- tools/testing/selftests/seccomp/seccomp_bpf.c | 46 ++++++++++++++++++++------- 1 file changed, 35 insertions(+), 11 deletions(-) diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c index e7bc5d3..e38cc54 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. */ -- 2.6.0.rc2.230.g3dd15c0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/