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selftests/seccomp: Be more precise with syscall arguments.

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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 <rsesek@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
This commit is contained in:
Robert Sesek 2015-11-02 15:28:49 -05:00 committed by Shuah Khan
parent 256d0afb11
commit fd88d16c58
1 changed files with 35 additions and 11 deletions
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46
tools/testing/selftests/seccomp/seccomp_bpf.c
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@ -29,6 +29,9 @@
#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>
@ -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. */