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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2025 Meta Platforms, Inc. and affiliates. */
#include <test_progs.h>
#include <network_helpers.h>
#include "file_reader.skel.h"
#include "file_reader_fail.skel.h"
#include <dlfcn.h>
#include <sys/mman.h>
const char *user_ptr = "hello world";
char file_contents[256000];
void *get_executable_base_addr(void)
{
Dl_info info;
if (!dladdr((void *)&get_executable_base_addr, &info)) {
fprintf(stderr, "dladdr failed\n");
return NULL;
}
return info.dli_fbase;
}
static int initialize_file_contents(void)
{
int fd, page_sz = sysconf(_SC_PAGESIZE);
ssize_t n = 0, cur, off;
void *addr;
fd = open("/proc/self/exe", O_RDONLY);
if (!ASSERT_OK_FD(fd, "Open /proc/self/exe\n"))
return 1;
do {
cur = read(fd, file_contents + n, sizeof(file_contents) - n);
if (!ASSERT_GT(cur, 0, "read success"))
break;
n += cur;
} while (n < sizeof(file_contents));
close(fd);
if (!ASSERT_EQ(n, sizeof(file_contents), "Read /proc/self/exe\n"))
return 1;
addr = get_executable_base_addr();
if (!ASSERT_NEQ(addr, NULL, "get executable address"))
return 1;
/* page-align base file address */
addr = (void *)((unsigned long)addr & ~(page_sz - 1));
/*
* Page out range 0..512K, use 0..256K for positive tests and
* 256K..512K for negative tests expecting page faults
*/
for (off = 0; off < sizeof(file_contents) * 2; off += page_sz) {
if (!ASSERT_OK(madvise(addr + off, page_sz, MADV_PAGEOUT),
"madvise pageout"))
return errno;
}
return 0;
}
static void run_test(const char *prog_name)
{
struct file_reader *skel;
struct bpf_program *prog;
int err, fd;
err = initialize_file_contents();
if (!ASSERT_OK(err, "initialize file contents"))
return;
skel = file_reader__open();
if (!ASSERT_OK_PTR(skel, "file_reader__open"))
return;
bpf_object__for_each_program(prog, skel->obj) {
bpf_program__set_autoload(prog, strcmp(bpf_program__name(prog), prog_name) == 0);
}
memcpy(skel->bss->user_buf, file_contents, sizeof(file_contents));
skel->bss->pid = getpid();
err = file_reader__load(skel);
if (!ASSERT_OK(err, "file_reader__load"))
goto cleanup;
err = file_reader__attach(skel);
if (!ASSERT_OK(err, "file_reader__attach"))
goto cleanup;
fd = open("/proc/self/exe", O_RDONLY);
if (fd >= 0)
close(fd);
ASSERT_EQ(skel->bss->err, 0, "err");
ASSERT_EQ(skel->bss->run_success, 1, "run_success");
cleanup:
file_reader__destroy(skel);
}
void test_file_reader(void)
{
if (test__start_subtest("on_open_expect_fault"))
run_test("on_open_expect_fault");
if (test__start_subtest("on_open_validate_file_read"))
run_test("on_open_validate_file_read");
if (test__start_subtest("negative"))
RUN_TESTS(file_reader_fail);
}
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