mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-25 13:14:07 +08:00
5b0764b2d3
Since bpf is not using rlimit memlock for the memory accounting and control, do not change the limit in sample applications. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20201201215900.3569844-35-guro@fb.com
99 lines
2.3 KiB
C
99 lines
2.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <linux/filter.h>
|
|
#include <linux/seccomp.h>
|
|
#include <sys/prctl.h>
|
|
#include <bpf/bpf.h>
|
|
#include <bpf/libbpf.h>
|
|
#include <sys/resource.h>
|
|
#include "trace_helpers.h"
|
|
|
|
#ifdef __mips__
|
|
#define MAX_ENTRIES 6000 /* MIPS n64 syscalls start at 5000 */
|
|
#else
|
|
#define MAX_ENTRIES 1024
|
|
#endif
|
|
|
|
/* install fake seccomp program to enable seccomp code path inside the kernel,
|
|
* so that our kprobe attached to seccomp_phase1() can be triggered
|
|
*/
|
|
static void install_accept_all_seccomp(void)
|
|
{
|
|
struct sock_filter filter[] = {
|
|
BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW),
|
|
};
|
|
struct sock_fprog prog = {
|
|
.len = (unsigned short)(sizeof(filter)/sizeof(filter[0])),
|
|
.filter = filter,
|
|
};
|
|
if (prctl(PR_SET_SECCOMP, 2, &prog))
|
|
perror("prctl");
|
|
}
|
|
|
|
int main(int ac, char **argv)
|
|
{
|
|
struct bpf_link *link = NULL;
|
|
struct bpf_program *prog;
|
|
struct bpf_object *obj;
|
|
int key, fd, progs_fd;
|
|
const char *section;
|
|
char filename[256];
|
|
FILE *f;
|
|
|
|
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
|
|
obj = bpf_object__open_file(filename, NULL);
|
|
if (libbpf_get_error(obj)) {
|
|
fprintf(stderr, "ERROR: opening BPF object file failed\n");
|
|
return 0;
|
|
}
|
|
|
|
prog = bpf_object__find_program_by_name(obj, "bpf_prog1");
|
|
if (!prog) {
|
|
printf("finding a prog in obj file failed\n");
|
|
goto cleanup;
|
|
}
|
|
|
|
/* load BPF program */
|
|
if (bpf_object__load(obj)) {
|
|
fprintf(stderr, "ERROR: loading BPF object file failed\n");
|
|
goto cleanup;
|
|
}
|
|
|
|
link = bpf_program__attach(prog);
|
|
if (libbpf_get_error(link)) {
|
|
fprintf(stderr, "ERROR: bpf_program__attach failed\n");
|
|
link = NULL;
|
|
goto cleanup;
|
|
}
|
|
|
|
progs_fd = bpf_object__find_map_fd_by_name(obj, "progs");
|
|
if (progs_fd < 0) {
|
|
fprintf(stderr, "ERROR: finding a map in obj file failed\n");
|
|
goto cleanup;
|
|
}
|
|
|
|
bpf_object__for_each_program(prog, obj) {
|
|
section = bpf_program__section_name(prog);
|
|
/* register only syscalls to PROG_ARRAY */
|
|
if (sscanf(section, "kprobe/%d", &key) != 1)
|
|
continue;
|
|
|
|
fd = bpf_program__fd(prog);
|
|
bpf_map_update_elem(progs_fd, &key, &fd, BPF_ANY);
|
|
}
|
|
|
|
install_accept_all_seccomp();
|
|
|
|
f = popen("dd if=/dev/zero of=/dev/null count=5", "r");
|
|
(void) f;
|
|
|
|
read_trace_pipe();
|
|
|
|
cleanup:
|
|
bpf_link__destroy(link);
|
|
bpf_object__close(obj);
|
|
return 0;
|
|
}
|