Re: [RFC PATCH v4 09/29] bpf tools: Collect version and license from ELF sections
On Thu, May 28, 2015 at 11:34:37AM +0800, Wangnan (F) wrote:
> >...
> >>+static int
> >>+bpf_object__init_kversion(struct bpf_object *obj,
> >>+ void *data, size_t size)
> >>+{
> >>+ u32 kver;
> >>+ if (size < sizeof(kver)) {
> >shouldn't it be '!=' ?
>
> Is it possible that LLVM pads 'version' section so the size of it becomes
> longer than sizeof(u32)?
llvm will not be padding a section unless user asks for it.
Try objdump on *_kern.o
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC PATCH v4 09/29] bpf tools: Collect version and license from ELF sections
On 2015/5/28 9:48, Alexei Starovoitov wrote:
On Wed, May 27, 2015 at 05:19:44AM +, Wang Nan wrote:
Expand bpf_obj_elf_collect() to collect license and kernel version
information in eBPF object file. eBPF object file should have a section
named 'license', which contains a string. It should also have a section
named 'version', contains a u32 LINUX_VERSION_CODE.
bpf_obj_validate() is introduced to validate object file after loaded.
Currently it only check existance of 'version' section.
Signed-off-by: Wang Nan
---
...
+static int
+bpf_object__init_kversion(struct bpf_object *obj,
+ void *data, size_t size)
+{
+ u32 kver;
+ if (size < sizeof(kver)) {
shouldn't it be '!=' ?
Is it possible that LLVM pads 'version' section so the size of it becomes
longer than sizeof(u32)?
Thank you.
+ pr_warning("invalid kver section in %s\n", obj->path);
+ return -EINVAL;
+ }
+ memcpy(, data, sizeof(kver));
+ obj->kern_version = kver;
+ pr_debug("kernel version of %s is %x\n", obj->path,
+obj->kern_version);
+ return 0;
+}
+
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC PATCH v4 09/29] bpf tools: Collect version and license from ELF sections
On Wed, May 27, 2015 at 05:19:44AM +, Wang Nan wrote:
> Expand bpf_obj_elf_collect() to collect license and kernel version
> information in eBPF object file. eBPF object file should have a section
> named 'license', which contains a string. It should also have a section
> named 'version', contains a u32 LINUX_VERSION_CODE.
>
> bpf_obj_validate() is introduced to validate object file after loaded.
> Currently it only check existance of 'version' section.
>
> Signed-off-by: Wang Nan
> ---
...
> +static int
> +bpf_object__init_kversion(struct bpf_object *obj,
> + void *data, size_t size)
> +{
> + u32 kver;
> + if (size < sizeof(kver)) {
shouldn't it be '!=' ?
> + pr_warning("invalid kver section in %s\n", obj->path);
> + return -EINVAL;
> + }
> + memcpy(, data, sizeof(kver));
> + obj->kern_version = kver;
> + pr_debug("kernel version of %s is %x\n", obj->path,
> + obj->kern_version);
> + return 0;
> +}
> +
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC PATCH v4 09/29] bpf tools: Collect version and license from ELF sections
On 2015/5/28 9:48, Alexei Starovoitov wrote:
On Wed, May 27, 2015 at 05:19:44AM +, Wang Nan wrote:
Expand bpf_obj_elf_collect() to collect license and kernel version
information in eBPF object file. eBPF object file should have a section
named 'license', which contains a string. It should also have a section
named 'version', contains a u32 LINUX_VERSION_CODE.
bpf_obj_validate() is introduced to validate object file after loaded.
Currently it only check existance of 'version' section.
Signed-off-by: Wang Nan wangn...@huawei.com
---
...
+static int
+bpf_object__init_kversion(struct bpf_object *obj,
+ void *data, size_t size)
+{
+ u32 kver;
+ if (size sizeof(kver)) {
shouldn't it be '!=' ?
Is it possible that LLVM pads 'version' section so the size of it becomes
longer than sizeof(u32)?
Thank you.
+ pr_warning(invalid kver section in %s\n, obj-path);
+ return -EINVAL;
+ }
+ memcpy(kver, data, sizeof(kver));
+ obj-kern_version = kver;
+ pr_debug(kernel version of %s is %x\n, obj-path,
+obj-kern_version);
+ return 0;
+}
+
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC PATCH v4 09/29] bpf tools: Collect version and license from ELF sections
On Wed, May 27, 2015 at 05:19:44AM +, Wang Nan wrote:
Expand bpf_obj_elf_collect() to collect license and kernel version
information in eBPF object file. eBPF object file should have a section
named 'license', which contains a string. It should also have a section
named 'version', contains a u32 LINUX_VERSION_CODE.
bpf_obj_validate() is introduced to validate object file after loaded.
Currently it only check existance of 'version' section.
Signed-off-by: Wang Nan wangn...@huawei.com
---
...
+static int
+bpf_object__init_kversion(struct bpf_object *obj,
+ void *data, size_t size)
+{
+ u32 kver;
+ if (size sizeof(kver)) {
shouldn't it be '!=' ?
+ pr_warning(invalid kver section in %s\n, obj-path);
+ return -EINVAL;
+ }
+ memcpy(kver, data, sizeof(kver));
+ obj-kern_version = kver;
+ pr_debug(kernel version of %s is %x\n, obj-path,
+ obj-kern_version);
+ return 0;
+}
+
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC PATCH v4 09/29] bpf tools: Collect version and license from ELF sections
On Thu, May 28, 2015 at 11:34:37AM +0800, Wangnan (F) wrote:
...
+static int
+bpf_object__init_kversion(struct bpf_object *obj,
+ void *data, size_t size)
+{
+ u32 kver;
+ if (size sizeof(kver)) {
shouldn't it be '!=' ?
Is it possible that LLVM pads 'version' section so the size of it becomes
longer than sizeof(u32)?
llvm will not be padding a section unless user asks for it.
Try objdump on *_kern.o
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[RFC PATCH v4 09/29] bpf tools: Collect version and license from ELF sections
Expand bpf_obj_elf_collect() to collect license and kernel version
information in eBPF object file. eBPF object file should have a section
named 'license', which contains a string. It should also have a section
named 'version', contains a u32 LINUX_VERSION_CODE.
bpf_obj_validate() is introduced to validate object file after loaded.
Currently it only check existance of 'version' section.
Signed-off-by: Wang Nan
---
tools/lib/bpf/libbpf.c | 52 ++
1 file changed, 52 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 16e47a3..15525ad 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -14,6 +14,7 @@
#include
#include
#include
+#include
#include
#include
#include
@@ -81,6 +82,8 @@ void libbpf_set_print(int (*warn)(const char *format, ...),
#endif
struct bpf_object {
+ char license[64];
+ u32 kern_version;
/*
* Information when doing elf related work. Only valid if fd
* is valid.
@@ -197,6 +200,32 @@ mismatch:
return -EINVAL;
}
+static int
+bpf_object__init_license(struct bpf_object *obj,
+void *data, size_t size)
+{
+ memcpy(obj->license, data,
+ min(size, sizeof(obj->license) - 1));
+ pr_debug("license of %s is %s\n", obj->path, obj->license);
+ return 0;
+}
+
+static int
+bpf_object__init_kversion(struct bpf_object *obj,
+ void *data, size_t size)
+{
+ u32 kver;
+ if (size < sizeof(kver)) {
+ pr_warning("invalid kver section in %s\n", obj->path);
+ return -EINVAL;
+ }
+ memcpy(, data, sizeof(kver));
+ obj->kern_version = kver;
+ pr_debug("kernel version of %s is %x\n", obj->path,
+obj->kern_version);
+ return 0;
+}
+
static int bpf_object__elf_collect(struct bpf_object *obj)
{
Elf *elf = obj->efile.elf;
@@ -243,11 +272,32 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
name, (unsigned long)data->d_size,
(int)sh.sh_link, (unsigned long)sh.sh_flags,
(int)sh.sh_type);
+
+ if (strcmp(name, "license") == 0)
+ err = bpf_object__init_license(obj,
+ data->d_buf,
+ data->d_size);
+ else if (strcmp(name, "version") == 0)
+ err = bpf_object__init_kversion(obj,
+ data->d_buf,
+ data->d_size);
+ if (err)
+ goto out;
}
out:
return err;
}
+static int bpf_object__validate(struct bpf_object *obj)
+{
+ if (obj->kern_version == 0) {
+ pr_warning("%s doesn't provide kernel version\n",
+ obj->path);
+ return -EINVAL;
+ }
+ return 0;
+}
+
struct bpf_object *bpf_object__open(const char *path)
{
struct bpf_object *obj;
@@ -273,6 +323,8 @@ struct bpf_object *bpf_object__open(const char *path)
goto out;
if (bpf_object__elf_collect(obj))
goto out;
+ if (bpf_object__validate(obj))
+ goto out;
bpf_object__elf_finish(obj);
return obj;
--
1.8.3.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[RFC PATCH v4 09/29] bpf tools: Collect version and license from ELF sections
Expand bpf_obj_elf_collect() to collect license and kernel version
information in eBPF object file. eBPF object file should have a section
named 'license', which contains a string. It should also have a section
named 'version', contains a u32 LINUX_VERSION_CODE.
bpf_obj_validate() is introduced to validate object file after loaded.
Currently it only check existance of 'version' section.
Signed-off-by: Wang Nan wangn...@huawei.com
---
tools/lib/bpf/libbpf.c | 52 ++
1 file changed, 52 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 16e47a3..15525ad 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -14,6 +14,7 @@
#include fcntl.h
#include errno.h
#include asm/unistd.h
+#include linux/kernel.h
#include linux/bpf.h
#include libelf.h
#include gelf.h
@@ -81,6 +82,8 @@ void libbpf_set_print(int (*warn)(const char *format, ...),
#endif
struct bpf_object {
+ char license[64];
+ u32 kern_version;
/*
* Information when doing elf related work. Only valid if fd
* is valid.
@@ -197,6 +200,32 @@ mismatch:
return -EINVAL;
}
+static int
+bpf_object__init_license(struct bpf_object *obj,
+void *data, size_t size)
+{
+ memcpy(obj-license, data,
+ min(size, sizeof(obj-license) - 1));
+ pr_debug(license of %s is %s\n, obj-path, obj-license);
+ return 0;
+}
+
+static int
+bpf_object__init_kversion(struct bpf_object *obj,
+ void *data, size_t size)
+{
+ u32 kver;
+ if (size sizeof(kver)) {
+ pr_warning(invalid kver section in %s\n, obj-path);
+ return -EINVAL;
+ }
+ memcpy(kver, data, sizeof(kver));
+ obj-kern_version = kver;
+ pr_debug(kernel version of %s is %x\n, obj-path,
+obj-kern_version);
+ return 0;
+}
+
static int bpf_object__elf_collect(struct bpf_object *obj)
{
Elf *elf = obj-efile.elf;
@@ -243,11 +272,32 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
name, (unsigned long)data-d_size,
(int)sh.sh_link, (unsigned long)sh.sh_flags,
(int)sh.sh_type);
+
+ if (strcmp(name, license) == 0)
+ err = bpf_object__init_license(obj,
+ data-d_buf,
+ data-d_size);
+ else if (strcmp(name, version) == 0)
+ err = bpf_object__init_kversion(obj,
+ data-d_buf,
+ data-d_size);
+ if (err)
+ goto out;
}
out:
return err;
}
+static int bpf_object__validate(struct bpf_object *obj)
+{
+ if (obj-kern_version == 0) {
+ pr_warning(%s doesn't provide kernel version\n,
+ obj-path);
+ return -EINVAL;
+ }
+ return 0;
+}
+
struct bpf_object *bpf_object__open(const char *path)
{
struct bpf_object *obj;
@@ -273,6 +323,8 @@ struct bpf_object *bpf_object__open(const char *path)
goto out;
if (bpf_object__elf_collect(obj))
goto out;
+ if (bpf_object__validate(obj))
+ goto out;
bpf_object__elf_finish(obj);
return obj;
--
1.8.3.4
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
