From: Hou Tao <houtao1@xxxxxxxxxx> If an abnormally huge cnt is used for multi-kprobes attachment, the following warning will be reported: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 392 at mm/util.c:632 kvmalloc_node+0xd9/0xe0 Modules linked in: bpf_testmod(O) CPU: 1 PID: 392 Comm: test_progs Tainted: G ...... 6.7.0-rc3+ #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ...... RIP: 0010:kvmalloc_node+0xd9/0xe0 ? __warn+0x89/0x150 ? kvmalloc_node+0xd9/0xe0 bpf_kprobe_multi_link_attach+0x87/0x670 __sys_bpf+0x2a28/0x2bc0 __x64_sys_bpf+0x1a/0x30 do_syscall_64+0x36/0xb0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 RIP: 0033:0x7fbe067f0e0d ...... </TASK> ---[ end trace 0000000000000000 ]--- So add a test to ensure the warning is fixed. Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx> --- .../selftests/bpf/prog_tests/kprobe_multi_test.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c index 4041cfa670eb..a340b6047657 100644 --- a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c +++ b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c @@ -300,6 +300,20 @@ static void test_attach_api_fails(void) if (!ASSERT_EQ(libbpf_get_error(link), -EINVAL, "fail_5_error")) goto cleanup; + /* fail_6 - abnormal cnt */ + opts.addrs = (const unsigned long *) addrs; + opts.syms = NULL; + opts.cnt = INT_MAX; + opts.cookies = NULL; + + link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual, + NULL, &opts); + if (!ASSERT_ERR_PTR(link, "fail_6")) + goto cleanup; + + if (!ASSERT_EQ(libbpf_get_error(link), -ENOMEM, "fail_6_error")) + goto cleanup; + cleanup: bpf_link__destroy(link); kprobe_multi__destroy(skel); -- 2.29.2
