linux-kernel - [RFC PATCH v8 09/49] bpf tools: Collect map definitions from 'maps' section

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1435149113-51142-10-git-send-email-wangnan0@huawei.com>
Date:	Wed, 24 Jun 2015 12:31:13 +0000
From:	Wang Nan <wangnan0@...wei.com>
To:	<acme@...nel.org>, <ast@...mgrid.com>, <brendan.d.gregg@...il.com>,
	<daniel@...earbox.net>, <namhyung@...nel.org>,
	<masami.hiramatsu.pt@...achi.com>, <paulus@...ba.org>,
	<a.p.zijlstra@...llo.nl>, <mingo@...hat.com>, <jolsa@...nel.org>,
	<dsahern@...il.com>
CC:	<linux-kernel@...r.kernel.org>, <lizefan@...wei.com>,
	<hekuang@...wei.com>, <xiakaixu@...wei.com>, <pi3orama@....com>
Subject: [RFC PATCH v8 09/49] bpf tools: Collect map definitions from 'maps' section

If maps are used by eBPF programs, corresponding object file(s) should
contain a section named 'map'. Which contains map definitions. This
patch copies the data of the whole section. Map data parsing should be
acted just before map loading.

Signed-off-by: Wang Nan <wangnan0@...wei.com>
Acked-by: Alexei Starovoitov <ast@...mgrid.com>
---
 tools/lib/bpf/libbpf.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 3bd183c..3315f00 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -81,6 +81,9 @@ void libbpf_set_print(libbpf_print_fn_t warn,
 struct bpf_object {
 	char license[64];
 	u32 kern_version;
+	void *maps_buf;
+	size_t maps_buf_sz;
+
 	/*
 	 * Information when doing elf related work. Only valid if fd
 	 * is valid.
@@ -249,6 +252,28 @@ bpf_object__init_kversion(struct bpf_object *obj,
 	return 0;
 }
 
+static int
+bpf_object__init_maps(struct bpf_object *obj, void *data,
+		      size_t size)
+{
+	if (size == 0) {
+		pr_debug("%s doesn't need map definition\n",
+			 obj->path);
+		return 0;
+	}
+
+	obj->maps_buf = malloc(size);
+	if (!obj->maps_buf) {
+		pr_warning("malloc maps failed: %s\n", obj->path);
+		return -ENOMEM;
+	}
+
+	obj->maps_buf_sz = size;
+	memcpy(obj->maps_buf, data, size);
+	pr_debug("maps in %s: %ld bytes\n", obj->path, (long)size);
+	return 0;
+}
+
 static int bpf_object__elf_collect(struct bpf_object *obj)
 {
 	Elf *elf = obj->efile.elf;
@@ -304,6 +329,9 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
 			err = bpf_object__init_kversion(obj,
 							data->d_buf,
 							data->d_size);
+		else if (strcmp(name, "maps") == 0)
+			err = bpf_object__init_maps(obj, data->d_buf,
+						    data->d_size);
 		if (err)
 			goto out;
 	}
@@ -381,5 +409,6 @@ void bpf_object__close(struct bpf_object *obj)
 
 	bpf_object__elf_finish(obj);
 
+	zfree(&obj->maps_buf);
 	free(obj);
 }
-- 
1.8.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/