ladybird/Tests/Kernel/TestMemoryDeviceMmap.cpp
Liav A cf0dbc9069 Tests: Add a unit test to ensure the /dev/mem device works correctly
To ensure everything works as expected, a unit test was added with
multiple scenarios.
This binary has to have the SetUID flag, and we also bind-mount the
/usr/Tests directory to allow running of SetUID binaries.
2021-10-22 13:13:00 +02:00

52 lines
1.3 KiB
C++

/*
* Copyright (c) 2021, Liav A. <liavalb@hotmail.co.il>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Types.h>
#include <LibTest/TestCase.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <unistd.h>
static ALWAYS_INLINE bool mem_chunk(int fd, u64 base, u64 length)
{
u64 mmoffset = base % sysconf(_SC_PAGESIZE);
void* mmp = mmap(NULL, mmoffset + length, PROT_READ, MAP_SHARED, fd, base - mmoffset);
return mmp != MAP_FAILED;
}
TEST_CASE(test_memory_access_device_mmap)
{
int rc = geteuid();
EXPECT_EQ(rc, 0);
int fd = open("/dev/mem", O_RDONLY);
EXPECT_EQ(fd < 0, false);
// FIXME: This is expected to work on QEMU machines (both 440FX and Q35),
// however, it will be much nicer to have some sort of a node in the ProcFS
// to expose physical memory ranges (e820 memory map).
auto result = mem_chunk(fd, 0xe0000, 0x100000 - 0xe0000);
EXPECT_EQ(result, true);
result = mem_chunk(fd, 0x100000, 0x200000 - 0x100000);
EXPECT_EQ(result, false);
result = mem_chunk(fd, 0xf0000, 70000);
EXPECT_EQ(result, false);
result = mem_chunk(fd, 0xfffc0000, 16384);
EXPECT_EQ(result, true);
result = mem_chunk(fd, 0xfffc0000, 0x100000);
EXPECT_EQ(result, false);
}