From 06ac0186bd242d44f5703ce64ee0077b317c86bb Mon Sep 17 00:00:00 2001 From: Andrey Ignatov Date: Wed, 18 Dec 2019 23:44:38 -0800 Subject: [PATCH] selftests/bpf: Test BPF_F_REPLACE in cgroup_attach_multi Test replacing a cgroup-bpf program attached with BPF_F_ALLOW_MULTI and possible failure modes: invalid combination of flags, invalid replace_bpf_fd, replacing a non-attachd to specified cgroup program. Example of program replacing: # gdb -q --args ./test_progs --name=cgroup_attach_multi ... Breakpoint 1, test_cgroup_attach_multi () at cgroup_attach_multi.c:227 (gdb) [1]+ Stopped gdb -q --args ./test_progs --name=cgroup_attach_multi # bpftool c s /mnt/cgroup2/cgroup-test-work-dir/cg1 ID AttachType AttachFlags Name 2133 egress multi 2134 egress multi # fg gdb -q --args ./test_progs --name=cgroup_attach_multi (gdb) c Continuing. Breakpoint 2, test_cgroup_attach_multi () at cgroup_attach_multi.c:233 (gdb) [1]+ Stopped gdb -q --args ./test_progs --name=cgroup_attach_multi # bpftool c s /mnt/cgroup2/cgroup-test-work-dir/cg1 ID AttachType AttachFlags Name 2139 egress multi 2134 egress multi Signed-off-by: Andrey Ignatov Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/7b9b83e8d5fb82e15b034341bd40b6fb2431eeba.1576741281.git.rdna@fb.com --- .../bpf/prog_tests/cgroup_attach_multi.c | 53 +++++++++++++++++-- 1 file changed, 50 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_attach_multi.c b/tools/testing/selftests/bpf/prog_tests/cgroup_attach_multi.c index 4eaab7435044..2ff21dbce179 100644 --- a/tools/testing/selftests/bpf/prog_tests/cgroup_attach_multi.c +++ b/tools/testing/selftests/bpf/prog_tests/cgroup_attach_multi.c @@ -78,7 +78,8 @@ void test_cgroup_attach_multi(void) { __u32 prog_ids[4], prog_cnt = 0, attach_flags, saved_prog_id; int cg1 = 0, cg2 = 0, cg3 = 0, cg4 = 0, cg5 = 0, key = 0; - int allow_prog[6] = {-1}; + DECLARE_LIBBPF_OPTS(bpf_prog_attach_opts, attach_opts); + int allow_prog[7] = {-1}; unsigned long long value; __u32 duration = 0; int i = 0; @@ -189,6 +190,52 @@ void test_cgroup_attach_multi(void) CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value)); CHECK_FAIL(value != 1 + 2 + 8 + 16); + /* test replace */ + + attach_opts.flags = BPF_F_ALLOW_OVERRIDE | BPF_F_REPLACE; + attach_opts.replace_prog_fd = allow_prog[0]; + if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1, + BPF_CGROUP_INET_EGRESS, &attach_opts), + "fail_prog_replace_override", "unexpected success\n")) + goto err; + CHECK_FAIL(errno != EINVAL); + + attach_opts.flags = BPF_F_REPLACE; + if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1, + BPF_CGROUP_INET_EGRESS, &attach_opts), + "fail_prog_replace_no_multi", "unexpected success\n")) + goto err; + CHECK_FAIL(errno != EINVAL); + + attach_opts.flags = BPF_F_ALLOW_MULTI | BPF_F_REPLACE; + attach_opts.replace_prog_fd = -1; + if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1, + BPF_CGROUP_INET_EGRESS, &attach_opts), + "fail_prog_replace_bad_fd", "unexpected success\n")) + goto err; + CHECK_FAIL(errno != EBADF); + + /* replacing a program that is not attached to cgroup should fail */ + attach_opts.replace_prog_fd = allow_prog[3]; + if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1, + BPF_CGROUP_INET_EGRESS, &attach_opts), + "fail_prog_replace_no_ent", "unexpected success\n")) + goto err; + CHECK_FAIL(errno != ENOENT); + + /* replace 1st from the top program */ + attach_opts.replace_prog_fd = allow_prog[0]; + if (CHECK(bpf_prog_attach_xattr(allow_prog[6], cg1, + BPF_CGROUP_INET_EGRESS, &attach_opts), + "prog_replace", "errno=%d\n", errno)) + goto err; + + value = 0; + CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0)); + CHECK_FAIL(system(PING_CMD)); + CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value)); + CHECK_FAIL(value != 64 + 2 + 8 + 16); + /* detach 3rd from bottom program and ping again */ if (CHECK(!bpf_prog_detach2(0, cg3, BPF_CGROUP_INET_EGRESS), "fail_prog_detach_from_cg3", "unexpected success\n")) @@ -202,7 +249,7 @@ void test_cgroup_attach_multi(void) CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0)); CHECK_FAIL(system(PING_CMD)); CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value)); - CHECK_FAIL(value != 1 + 2 + 16); + CHECK_FAIL(value != 64 + 2 + 16); /* detach 2nd from bottom program and ping again */ if (CHECK(bpf_prog_detach2(-1, cg4, BPF_CGROUP_INET_EGRESS), @@ -213,7 +260,7 @@ void test_cgroup_attach_multi(void) CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0)); CHECK_FAIL(system(PING_CMD)); CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value)); - CHECK_FAIL(value != 1 + 2 + 4); + CHECK_FAIL(value != 64 + 2 + 4); prog_cnt = 4; CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS,