linux/tools/testing/selftests/bpf/flow_dissector_load.c
Yonghong Song b31d30d9be tools/bpf: add unlimited rlimit for flow_dissector_load
On our test machine, bpf selftest test_flow_dissector.sh failed
with the following error:
  # ./test_flow_dissector.sh
  bpffs not mounted. Mounting...
  libbpf: failed to create map (name: 'jmp_table'): Operation not permitted
  libbpf: failed to load object 'bpf_flow.o'
  ./flow_dissector_load: bpf_prog_load bpf_flow.o
  selftests: test_flow_dissector [FAILED]

Let us increase the rlimit to remove the above map
creation failure.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-30 23:31:21 +01:00

143 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <error.h>
#include <errno.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <bpf/bpf.h>
#include <bpf/libbpf.h>
#include "bpf_rlimit.h"
const char *cfg_pin_path = "/sys/fs/bpf/flow_dissector";
const char *cfg_map_name = "jmp_table";
bool cfg_attach = true;
char *cfg_section_name;
char *cfg_path_name;
static void load_and_attach_program(void)
{
struct bpf_program *prog, *main_prog;
struct bpf_map *prog_array;
int i, fd, prog_fd, ret;
struct bpf_object *obj;
int prog_array_fd;
ret = bpf_prog_load(cfg_path_name, BPF_PROG_TYPE_FLOW_DISSECTOR, &obj,
&prog_fd);
if (ret)
error(1, 0, "bpf_prog_load %s", cfg_path_name);
main_prog = bpf_object__find_program_by_title(obj, cfg_section_name);
if (!main_prog)
error(1, 0, "bpf_object__find_program_by_title %s",
cfg_section_name);
prog_fd = bpf_program__fd(main_prog);
if (prog_fd < 0)
error(1, 0, "bpf_program__fd");
prog_array = bpf_object__find_map_by_name(obj, cfg_map_name);
if (!prog_array)
error(1, 0, "bpf_object__find_map_by_name %s", cfg_map_name);
prog_array_fd = bpf_map__fd(prog_array);
if (prog_array_fd < 0)
error(1, 0, "bpf_map__fd %s", cfg_map_name);
i = 0;
bpf_object__for_each_program(prog, obj) {
fd = bpf_program__fd(prog);
if (fd < 0)
error(1, 0, "bpf_program__fd");
if (fd != prog_fd) {
printf("%d: %s\n", i, bpf_program__title(prog, false));
bpf_map_update_elem(prog_array_fd, &i, &fd, BPF_ANY);
++i;
}
}
ret = bpf_prog_attach(prog_fd, 0 /* Ignore */, BPF_FLOW_DISSECTOR, 0);
if (ret)
error(1, 0, "bpf_prog_attach %s", cfg_path_name);
ret = bpf_object__pin(obj, cfg_pin_path);
if (ret)
error(1, 0, "bpf_object__pin %s", cfg_pin_path);
}
static void detach_program(void)
{
char command[64];
int ret;
ret = bpf_prog_detach(0, BPF_FLOW_DISSECTOR);
if (ret)
error(1, 0, "bpf_prog_detach");
/* To unpin, it is necessary and sufficient to just remove this dir */
sprintf(command, "rm -r %s", cfg_pin_path);
ret = system(command);
if (ret)
error(1, errno, command);
}
static void parse_opts(int argc, char **argv)
{
bool attach = false;
bool detach = false;
int c;
while ((c = getopt(argc, argv, "adp:s:")) != -1) {
switch (c) {
case 'a':
if (detach)
error(1, 0, "attach/detach are exclusive");
attach = true;
break;
case 'd':
if (attach)
error(1, 0, "attach/detach are exclusive");
detach = true;
break;
case 'p':
if (cfg_path_name)
error(1, 0, "only one prog name can be given");
cfg_path_name = optarg;
break;
case 's':
if (cfg_section_name)
error(1, 0, "only one section can be given");
cfg_section_name = optarg;
break;
}
}
if (detach)
cfg_attach = false;
if (cfg_attach && !cfg_path_name)
error(1, 0, "must provide a path to the BPF program");
if (cfg_attach && !cfg_section_name)
error(1, 0, "must provide a section name");
}
int main(int argc, char **argv)
{
parse_opts(argc, argv);
if (cfg_attach)
load_and_attach_program();
else
detach_program();
return 0;
}