[bpf-next,v2,01/10] bpf: btf: Make some of the API visible outside BTF
diff mbox series

Message ID 20200115171333.28811-2-kpsingh@chromium.org
State New
Headers show
Series
  • MAC and Audit policy using eBPF (KRSI)
Related show

Commit Message

KP Singh Jan. 15, 2020, 5:13 p.m. UTC
From: KP Singh <kpsingh@google.com>

- Add an extern for btf_vmlinux in btf.h
- Add btf_type_by_name_kind, the LSM code does the combination of
  btf_find_by_name_kind and btf_type_by_id quite often.

Signed-off-by: KP Singh <kpsingh@google.com>
---
 include/linux/btf.h |  8 ++++++++
 kernel/bpf/btf.c    | 17 +++++++++++++++++
 2 files changed, 25 insertions(+)

Comments

kbuild test robot Jan. 18, 2020, 12:44 p.m. UTC | #1
Hi KP,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on next-20200116]
[cannot apply to bpf-next/master bpf/master linus/master security/next-testing v5.5-rc6 v5.5-rc5 v5.5-rc4 v5.5-rc6]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/KP-Singh/MAC-and-Audit-policy-using-eBPF-KRSI/20200117-070342
base:    2747d5fdab78f43210256cd52fb2718e0b3cce74
config: nds32-defconfig (attached as .config)
compiler: nds32le-linux-gcc (GCC) 9.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=9.2.0 make.cross ARCH=nds32 

If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from kernel/bpf/core.c:27:
>> include/linux/btf.h:148:38: error: static declaration of 'btf_type_by_name_kind' follows non-static declaration
     148 | static inline const struct btf_type *btf_type_by_name_kind(
         |                                      ^~~~~~~~~~~~~~~~~~~~~
   include/linux/btf.h:70:24: note: previous declaration of 'btf_type_by_name_kind' was here
      70 | const struct btf_type *btf_type_by_name_kind(
         |                        ^~~~~~~~~~~~~~~~~~~~~

vim +/btf_type_by_name_kind +148 include/linux/btf.h

   136	
   137	#ifdef CONFIG_BPF_SYSCALL
   138	const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id);
   139	const char *btf_name_by_offset(const struct btf *btf, u32 offset);
   140	struct btf *btf_parse_vmlinux(void);
   141	struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog);
   142	#else
   143	static inline const struct btf_type *btf_type_by_id(const struct btf *btf,
   144							    u32 type_id)
   145	{
   146		return NULL;
   147	}
 > 148	static inline const struct btf_type *btf_type_by_name_kind(
   149		struct btf *btf, const char *name, u8 kind)
   150	{
   151		return ERR_PTR(-EOPNOTSUPP);
   152	}
   153	static inline const char *btf_name_by_offset(const struct btf *btf,
   154						     u32 offset)
   155	{
   156		return NULL;
   157	}
   158	#endif
   159	

---
0-DAY kernel test infrastructure                 Open Source Technology Center
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation
KP Singh Jan. 20, 2020, 11 a.m. UTC | #2
Thanks! I have fixed this in the v3 of the series. btf_find_by_name_kind
is independant of CONFIG_BPF_SYSCALL and btf_type_by_name_kind needs
to be as well.

The mistake was adding a static inline definition of the function
in the !CONFIG_BPF_SYSCALL section which is not needed in this case.

- KP

On 18-Jan 20:44, kbuild test robot wrote:
> Hi KP,
> 
> Thank you for the patch! Yet something to improve:
> 
> [auto build test ERROR on next-20200116]
> [cannot apply to bpf-next/master bpf/master linus/master security/next-testing v5.5-rc6 v5.5-rc5 v5.5-rc4 v5.5-rc6]
> [if your patch is applied to the wrong git tree, please drop us a note to help
> improve the system. BTW, we also suggest to use '--base' option to specify the
> base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
> 
> url:    https://github.com/0day-ci/linux/commits/KP-Singh/MAC-and-Audit-policy-using-eBPF-KRSI/20200117-070342
> base:    2747d5fdab78f43210256cd52fb2718e0b3cce74
> config: nds32-defconfig (attached as .config)
> compiler: nds32le-linux-gcc (GCC) 9.2.0
> reproduce:
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # save the attached .config to linux build tree
>         GCC_VERSION=9.2.0 make.cross ARCH=nds32 
> 
> If you fix the issue, kindly add following tag
> Reported-by: kbuild test robot <lkp@intel.com>
> 
> All errors (new ones prefixed by >>):
> 
>    In file included from kernel/bpf/core.c:27:
> >> include/linux/btf.h:148:38: error: static declaration of 'btf_type_by_name_kind' follows non-static declaration
>      148 | static inline const struct btf_type *btf_type_by_name_kind(
>          |                                      ^~~~~~~~~~~~~~~~~~~~~
>    include/linux/btf.h:70:24: note: previous declaration of 'btf_type_by_name_kind' was here
>       70 | const struct btf_type *btf_type_by_name_kind(
>          |                        ^~~~~~~~~~~~~~~~~~~~~
> 
> vim +/btf_type_by_name_kind +148 include/linux/btf.h
> 
>    136	
>    137	#ifdef CONFIG_BPF_SYSCALL
>    138	const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id);
>    139	const char *btf_name_by_offset(const struct btf *btf, u32 offset);
>    140	struct btf *btf_parse_vmlinux(void);
>    141	struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog);
>    142	#else
>    143	static inline const struct btf_type *btf_type_by_id(const struct btf *btf,
>    144							    u32 type_id)
>    145	{
>    146		return NULL;
>    147	}
>  > 148	static inline const struct btf_type *btf_type_by_name_kind(
>    149		struct btf *btf, const char *name, u8 kind)
>    150	{
>    151		return ERR_PTR(-EOPNOTSUPP);
>    152	}
>    153	static inline const char *btf_name_by_offset(const struct btf *btf,
>    154						     u32 offset)
>    155	{
>    156		return NULL;
>    157	}
>    158	#endif
>    159	
> 
> ---
> 0-DAY kernel test infrastructure                 Open Source Technology Center
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation

Patch
diff mbox series

diff --git a/include/linux/btf.h b/include/linux/btf.h
index 881e9b76ef49..dc650d294bc4 100644
--- a/include/linux/btf.h
+++ b/include/linux/btf.h
@@ -15,6 +15,7 @@  struct btf_type;
 union bpf_attr;
 
 extern const struct file_operations btf_fops;
+extern struct btf *btf_vmlinux;
 
 void btf_put(struct btf *btf);
 int btf_new_fd(const union bpf_attr *attr);
@@ -66,6 +67,8 @@  const struct btf_type *
 btf_resolve_size(const struct btf *btf, const struct btf_type *type,
 		 u32 *type_size, const struct btf_type **elem_type,
 		 u32 *total_nelems);
+const struct btf_type *btf_type_by_name_kind(
+	struct btf *btf, const char *name, u8 kind);
 
 #define for_each_member(i, struct_type, member)			\
 	for (i = 0, member = btf_type_member(struct_type);	\
@@ -142,6 +145,11 @@  static inline const struct btf_type *btf_type_by_id(const struct btf *btf,
 {
 	return NULL;
 }
+static inline const struct btf_type *btf_type_by_name_kind(
+	struct btf *btf, const char *name, u8 kind)
+{
+	return ERR_PTR(-EOPNOTSUPP);
+}
 static inline const char *btf_name_by_offset(const struct btf *btf,
 					     u32 offset)
 {
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 832b5d7fd892..b8968cec8718 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -436,6 +436,23 @@  const struct btf_type *btf_type_resolve_func_ptr(const struct btf *btf,
 	return NULL;
 }
 
+const struct btf_type *btf_type_by_name_kind(
+	struct btf *btf, const char *name, u8 kind)
+{
+	const struct btf_type *t;
+	s32 type_id;
+
+	type_id = btf_find_by_name_kind(btf, name, kind);
+	if (type_id < 0)
+		return ERR_PTR(-EINVAL);
+
+	t = btf_type_by_id(btf, type_id);
+	if (!t)
+		return ERR_PTR(-EINVAL);
+
+	return t;
+}
+
 /* Types that act only as a source, not sink or intermediate
  * type when resolving.
  */