From: Geliang Tang <tanggeliang@xxxxxxxxxx>
Run bpf_tcp_ca selftests (./test_progs -t bpf_tcp_ca) on a Loongarch
platform, some "Segmentation fault" errors occur:
'''
test_dctcp:PASS:bpf_dctcp__open_and_load 0 nsec
test_dctcp:FAIL:bpf_map__attach_struct_ops unexpected error: -524
#29/1 bpf_tcp_ca/dctcp:FAIL
test_cubic:PASS:bpf_cubic__open_and_load 0 nsec
test_cubic:FAIL:bpf_map__attach_struct_ops unexpected error: -524
#29/2 bpf_tcp_ca/cubic:FAIL
test_dctcp_fallback:PASS:dctcp_skel 0 nsec
test_dctcp_fallback:PASS:bpf_dctcp__load 0 nsec
test_dctcp_fallback:FAIL:dctcp link unexpected error: -524
#29/4 bpf_tcp_ca/dctcp_fallback:FAIL
test_write_sk_pacing:PASS:open_and_load 0 nsec
test_write_sk_pacing:FAIL:attach_struct_ops unexpected error: -524
#29/6 bpf_tcp_ca/write_sk_pacing:FAIL
test_update_ca:PASS:open 0 nsec
test_update_ca:FAIL:attach_struct_ops unexpected error: -524
settcpca:FAIL:setsockopt unexpected setsockopt: \
actual -1 == expected -1
(network_helpers.c:99: errno: No such file or directory) \
Failed to call post_socket_cb
start_test:FAIL:start_server_str unexpected start_server_str: \
actual -1 == expected -1
test_update_ca:FAIL:ca1_ca1_cnt unexpected ca1_ca1_cnt: \
actual 0 <= expected 0
#29/9 bpf_tcp_ca/update_ca:FAIL
#29 bpf_tcp_ca:FAIL
Caught signal #11!
Stack trace:
./test_progs(crash_handler+0x28)[0x5555567ed91c]
linux-vdso.so.1(__vdso_rt_sigreturn+0x0)[0x7ffffee408b0]
./test_progs(bpf_link__update_map+0x80)[0x555556824a78]
./test_progs(+0x94d68)[0x5555564c4d68]
./test_progs(test_bpf_tcp_ca+0xe8)[0x5555564c6a88]
./test_progs(+0x3bde54)[0x5555567ede54]
./test_progs(main+0x61c)[0x5555567efd54]
/usr/lib64/libc.so.6(+0x22208)[0x7ffff2aaa208]
/usr/lib64/libc.so.6(__libc_start_main+0xac)[0x7ffff2aaa30c]
./test_progs(_start+0x48)[0x55555646bca8]
Segmentation fault
'''
This is because BPF trampoline is not implemented on Loongarch yet,
"link" returned by bpf_map__attach_struct_ops() is NULL. test_progs
crashs when this NULL link passes to bpf_link__update_map(). This
patch adds NULL checks for all links in bpf_tcp_ca to fix these errors.
If "link" is NULL, goto the newly added label "out" to destroy the skel.
v2:
- use "goto out" instead of "return" as Eduard suggested.
Signed-off-by: Geliang Tang <tanggeliang@xxxxxxxxxx>
---
.../selftests/bpf/prog_tests/bpf_tcp_ca.c | 21 +++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c
index d842ff64bc2a..efc1bf2ff7de 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c
@@ -411,7 +411,8 @@ static void test_update_ca(void)
return;
link = bpf_map__attach_struct_ops(skel->maps.ca_update_1);
- ASSERT_OK_PTR(link, "attach_struct_ops");
+ if (!ASSERT_OK_PTR(link, "attach_struct_ops"))
+ goto out;
do_test(&opts);
saved_ca1_cnt = skel->bss->ca1_cnt;
@@ -425,6 +426,7 @@ static void test_update_ca(void)
ASSERT_GT(skel->bss->ca2_cnt, 0, "ca2_ca2_cnt");
bpf_link__destroy(link);
+out:
tcp_ca_update__destroy(skel);
}
@@ -447,7 +449,8 @@ static void test_update_wrong(void)
return;
link = bpf_map__attach_struct_ops(skel->maps.ca_update_1);
- ASSERT_OK_PTR(link, "attach_struct_ops");
+ if (!ASSERT_OK_PTR(link, "attach_struct_ops"))
+ goto out;
do_test(&opts);
saved_ca1_cnt = skel->bss->ca1_cnt;
@@ -460,11 +463,13 @@ static void test_update_wrong(void)
ASSERT_GT(skel->bss->ca1_cnt, saved_ca1_cnt, "ca2_ca1_cnt");
bpf_link__destroy(link);
+out:
tcp_ca_update__destroy(skel);
}
static void test_mixed_links(void)
{
+ struct bpf_link *link = NULL, *link_nl = NULL;
struct cb_opts cb_opts = {
.cc = "tcp_ca_update",
};
@@ -473,7 +478,6 @@ static void test_mixed_links(void)
.cb_opts = &cb_opts,
};
struct tcp_ca_update *skel;
- struct bpf_link *link, *link_nl;
int err;
skel = tcp_ca_update__open_and_load();
@@ -481,10 +485,12 @@ static void test_mixed_links(void)
return;
link_nl = bpf_map__attach_struct_ops(skel->maps.ca_no_link);
- ASSERT_OK_PTR(link_nl, "attach_struct_ops_nl");
+ if (!ASSERT_OK_PTR(link_nl, "attach_struct_ops_nl"))
+ goto out;
link = bpf_map__attach_struct_ops(skel->maps.ca_update_1);
- ASSERT_OK_PTR(link, "attach_struct_ops");
+ if (!ASSERT_OK_PTR(link, "attach_struct_ops"))
+ goto out;
do_test(&opts);
ASSERT_GT(skel->bss->ca1_cnt, 0, "ca1_ca1_cnt");
@@ -492,6 +498,7 @@ static void test_mixed_links(void)
err = bpf_link__update_map(link, skel->maps.ca_no_link);
ASSERT_ERR(err, "update_map");
+out:
bpf_link__destroy(link);
bpf_link__destroy(link_nl);
tcp_ca_update__destroy(skel);
@@ -536,7 +543,8 @@ static void test_link_replace(void)
bpf_link__destroy(link);
link = bpf_map__attach_struct_ops(skel->maps.ca_update_2);
- ASSERT_OK_PTR(link, "attach_struct_ops_2nd");
+ if (!ASSERT_OK_PTR(link, "attach_struct_ops_2nd"))
+ goto out;
/* BPF_F_REPLACE with a wrong old map Fd. It should fail!
*
@@ -559,6 +567,7 @@ static void test_link_replace(void)
bpf_link__destroy(link);
+out:
tcp_ca_update__destroy(skel);
}
--
2.43.0
