From: Alexei Starovoitov <ast@kernel.org>
To: <davem@davemloft.net>
Cc: <daniel@iogearbox.net>, <x86@kernel.org>,
<netdev@vger.kernel.org>, <bpf@vger.kernel.org>,
<kernel-team@fb.com>
Subject: [PATCH v2 bpf-next 07/12] bpf: attach raw_tp program with BTF via type name
Date: Wed, 9 Oct 2019 21:14:58 -0700 [thread overview]
Message-ID: <20191010041503.2526303-8-ast@kernel.org> (raw)
In-Reply-To: <20191010041503.2526303-1-ast@kernel.org>
BTF type id specified at program load time has all
necessary information to attach that program to raw tracepoint.
Use kernel type name to find raw tracepoint.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
kernel/bpf/syscall.c | 67 +++++++++++++++++++++++++++++---------------
1 file changed, 44 insertions(+), 23 deletions(-)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index b56c482c9760..03f36e73d84a 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1816,17 +1816,49 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
struct bpf_raw_tracepoint *raw_tp;
struct bpf_raw_event_map *btp;
struct bpf_prog *prog;
- char tp_name[128];
+ const char *tp_name;
+ char buf[128];
int tp_fd, err;
- if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
- sizeof(tp_name) - 1) < 0)
- return -EFAULT;
- tp_name[sizeof(tp_name) - 1] = 0;
+ prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
+ if (IS_ERR(prog))
+ return PTR_ERR(prog);
+
+ if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
+ prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
+ err = -EINVAL;
+ goto out_put_prog;
+ }
+
+ if (prog->type == BPF_PROG_TYPE_RAW_TRACEPOINT &&
+ prog->aux->attach_btf_id) {
+ if (attr->raw_tracepoint.name) {
+ /* raw_tp name should not be specified in raw_tp
+ * programs that were verified via in-kernel BTF info
+ */
+ err = -EINVAL;
+ goto out_put_prog;
+ }
+ /* raw_tp name is taken from type name instead */
+ tp_name = kernel_type_name(prog->aux->attach_btf_id);
+ /* skip the prefix */
+ tp_name += sizeof("btf_trace_") - 1;
+ } else {
+ if (strncpy_from_user(buf,
+ u64_to_user_ptr(attr->raw_tracepoint.name),
+ sizeof(buf) - 1) < 0) {
+ err = -EFAULT;
+ goto out_put_prog;
+ }
+ buf[sizeof(buf) - 1] = 0;
+ tp_name = buf;
+ }
btp = bpf_get_raw_tracepoint(tp_name);
- if (!btp)
- return -ENOENT;
+ if (!btp) {
+ err = -ENOENT;
+ goto out_put_prog;
+ }
raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
if (!raw_tp) {
@@ -1834,38 +1866,27 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
goto out_put_btp;
}
raw_tp->btp = btp;
-
- prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
- if (IS_ERR(prog)) {
- err = PTR_ERR(prog);
- goto out_free_tp;
- }
- if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
- prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
- err = -EINVAL;
- goto out_put_prog;
- }
+ raw_tp->prog = prog;
err = bpf_probe_register(raw_tp->btp, prog);
if (err)
- goto out_put_prog;
+ goto out_free_tp;
- raw_tp->prog = prog;
tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
O_CLOEXEC);
if (tp_fd < 0) {
bpf_probe_unregister(raw_tp->btp, prog);
err = tp_fd;
- goto out_put_prog;
+ goto out_free_tp;
}
return tp_fd;
-out_put_prog:
- bpf_prog_put(prog);
out_free_tp:
kfree(raw_tp);
out_put_btp:
bpf_put_raw_tracepoint(btp);
+out_put_prog:
+ bpf_prog_put(prog);
return err;
}
--
2.23.0
next prev parent reply other threads:[~2019-10-10 4:15 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-10 4:14 [PATCH v2 bpf-next 00/12] bpf: revolutionize bpf tracing Alexei Starovoitov
2019-10-10 4:14 ` [PATCH v2 bpf-next 01/12] bpf: add typecast to raw_tracepoints to help BTF generation Alexei Starovoitov
2019-10-10 4:14 ` [PATCH v2 bpf-next 02/12] bpf: add typecast to bpf helpers " Alexei Starovoitov
2019-10-10 4:14 ` [PATCH v2 bpf-next 03/12] bpf: process in-kernel BTF Alexei Starovoitov
2019-10-11 17:56 ` Andrii Nakryiko
2019-10-10 4:14 ` [PATCH v2 bpf-next 04/12] bpf: add attach_btf_id attribute to program load Alexei Starovoitov
2019-10-11 17:58 ` Andrii Nakryiko
2019-10-10 4:14 ` [PATCH v2 bpf-next 05/12] libbpf: auto-detect btf_id of raw_tracepoint Alexei Starovoitov
2019-10-11 18:02 ` Andrii Nakryiko
2019-10-11 18:07 ` Andrii Nakryiko
2019-10-12 0:40 ` Alexei Starovoitov
2019-10-12 1:29 ` Alexei Starovoitov
2019-10-12 4:38 ` Andrii Nakryiko
2019-10-12 4:53 ` Alexei Starovoitov
2019-10-12 4:39 ` Andrii Nakryiko
2019-10-10 4:14 ` [PATCH v2 bpf-next 06/12] bpf: implement accurate raw_tp context access via BTF Alexei Starovoitov
2019-10-11 18:31 ` Andrii Nakryiko
2019-10-11 23:13 ` Andrii Nakryiko
2019-10-10 4:14 ` Alexei Starovoitov [this message]
2019-10-11 18:44 ` [PATCH v2 bpf-next 07/12] bpf: attach raw_tp program with BTF via type name Andrii Nakryiko
2019-10-10 4:14 ` [PATCH v2 bpf-next 08/12] bpf: add support for BTF pointers to interpreter Alexei Starovoitov
2019-10-10 4:15 ` [PATCH v2 bpf-next 09/12] bpf: add support for BTF pointers to x86 JIT Alexei Starovoitov
2019-10-11 18:48 ` Andrii Nakryiko
2019-10-10 4:15 ` [PATCH v2 bpf-next 10/12] bpf: check types of arguments passed into helpers Alexei Starovoitov
2019-10-11 19:02 ` Andrii Nakryiko
2019-10-12 1:39 ` Alexei Starovoitov
2019-10-12 4:25 ` Andrii Nakryiko
2019-10-10 4:15 ` [PATCH v2 bpf-next 11/12] bpf: disallow bpf_probe_read[_str] helpers Alexei Starovoitov
2019-10-11 19:03 ` Andrii Nakryiko
2019-10-10 4:15 ` [PATCH v2 bpf-next 12/12] selftests/bpf: add kfree_skb raw_tp test Alexei Starovoitov
2019-10-10 11:07 ` Ido Schimmel
2019-10-10 19:07 ` Alexei Starovoitov
2019-10-11 19:05 ` Andrii Nakryiko
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