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author | Yonghong Song <yhs@fb.com> | 2019-02-07 09:34:51 -0800 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2019-02-07 18:22:31 -0800 |
commit | a4021a3579c52d5a5131820aeb94f531a7b082a7 (patch) | |
tree | 72209318ae2d78a637c60917794a2b6414343259 /tools/testing | |
parent | 62b8cea62e8bad0511260faab8e8de04c76a69af (diff) | |
download | linux-a4021a3579c52d5a5131820aeb94f531a7b082a7.tar.bz2 |
tools/bpf: add log_level to bpf_load_program_attr
The kernel verifier has three levels of logs:
0: no logs
1: logs mostly useful
> 1: verbose
Current libbpf API functions bpf_load_program_xattr() and
bpf_load_program() cannot specify log_level.
The bcc, however, provides an interface for user to
specify log_level 2 for verbose output.
This patch added log_level into structure
bpf_load_program_attr, so users, including bcc, can use
bpf_load_program_xattr() to change log_level. The
supported log_level is 0, 1, and 2.
The bpf selftest test_sock.c is modified to enable log_level = 2.
If the "verbose" in test_sock.c is changed to true,
the test will output logs like below:
$ ./test_sock
func#0 @0
0: R1=ctx(id=0,off=0,imm=0) R10=fp0,call_-1
0: (bf) r6 = r1
1: R1=ctx(id=0,off=0,imm=0) R6_w=ctx(id=0,off=0,imm=0) R10=fp0,call_-1
1: (61) r7 = *(u32 *)(r6 +28)
invalid bpf_context access off=28 size=4
Test case: bind4 load with invalid access: src_ip6 .. [PASS]
...
Test case: bind6 allow all .. [PASS]
Summary: 16 PASSED, 0 FAILED
Some test_sock tests are negative tests and verbose verifier
log will be printed out as shown in the above.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/testing')
-rw-r--r-- | tools/testing/selftests/bpf/test_sock.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/tools/testing/selftests/bpf/test_sock.c b/tools/testing/selftests/bpf/test_sock.c index 561ffb6d6433..fb679ac3d4b0 100644 --- a/tools/testing/selftests/bpf/test_sock.c +++ b/tools/testing/selftests/bpf/test_sock.c @@ -20,6 +20,7 @@ #define MAX_INSNS 512 char bpf_log_buf[BPF_LOG_BUF_SIZE]; +static bool verbose = false; struct sock_test { const char *descr; @@ -325,6 +326,7 @@ static int load_sock_prog(const struct bpf_insn *prog, enum bpf_attach_type attach_type) { struct bpf_load_program_attr attr; + int ret; memset(&attr, 0, sizeof(struct bpf_load_program_attr)); attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK; @@ -332,8 +334,13 @@ static int load_sock_prog(const struct bpf_insn *prog, attr.insns = prog; attr.insns_cnt = probe_prog_length(attr.insns); attr.license = "GPL"; + attr.log_level = 2; - return bpf_load_program_xattr(&attr, bpf_log_buf, BPF_LOG_BUF_SIZE); + ret = bpf_load_program_xattr(&attr, bpf_log_buf, BPF_LOG_BUF_SIZE); + if (verbose && ret < 0) + fprintf(stderr, "%s\n", bpf_log_buf); + + return ret; } static int attach_sock_prog(int cgfd, int progfd, |