* [PATCH bpf-next] libbpf: poison kernel-only integer types
@ 2020-01-10 18:19 Andrii Nakryiko
2020-01-10 18:29 ` [Potential Spoof] " Martin Lau
2020-01-10 18:39 ` Alexei Starovoitov
0 siblings, 2 replies; 3+ messages in thread
From: Andrii Nakryiko @ 2020-01-10 18:19 UTC (permalink / raw)
To: bpf, netdev, ast, daniel, kafai
Cc: andrii.nakryiko, kernel-team, Andrii Nakryiko
It's been a recurring issue with types like u32 slipping into libbpf source
code accidentally. This is not detected during builds inside kernel source
tree, but becomes a compilation error in libbpf's Github repo. Libbpf is
supposed to use only __{s,u}{8,16,32,64} typedefs, so poison {s,u}{8,16,32,64}
explicitly in every .c file. Doing that in a bit more centralized way, e.g.,
inside libbpf_internal.h breaks selftests, which are both using kernel u32 and
libbpf_internal.h.
This patch also fixes a new u32 occurence in libbpf.c, added recently.
Fixes: 590a00888250 ("bpf: libbpf: Add STRUCT_OPS support")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
tools/lib/bpf/bpf.c | 3 +++
tools/lib/bpf/bpf_prog_linfo.c | 3 +++
tools/lib/bpf/btf.c | 3 +++
tools/lib/bpf/btf_dump.c | 3 +++
tools/lib/bpf/hashmap.c | 3 +++
tools/lib/bpf/libbpf.c | 5 ++++-
tools/lib/bpf/libbpf_errno.c | 3 +++
tools/lib/bpf/libbpf_probes.c | 3 +++
tools/lib/bpf/netlink.c | 3 +++
tools/lib/bpf/nlattr.c | 3 +++
tools/lib/bpf/str_error.c | 3 +++
tools/lib/bpf/xsk.c | 3 +++
12 files changed, 37 insertions(+), 1 deletion(-)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index b0ecbe9ef2d4..500afe478e94 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -32,6 +32,9 @@
#include "libbpf.h"
#include "libbpf_internal.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
/*
* When building perf, unistd.h is overridden. __NR_bpf is
* required to be defined explicitly.
diff --git a/tools/lib/bpf/bpf_prog_linfo.c b/tools/lib/bpf/bpf_prog_linfo.c
index 3ed1a27b5f7c..bafca49cb1e6 100644
--- a/tools/lib/bpf/bpf_prog_linfo.c
+++ b/tools/lib/bpf/bpf_prog_linfo.c
@@ -8,6 +8,9 @@
#include "libbpf.h"
#include "libbpf_internal.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
struct bpf_prog_linfo {
void *raw_linfo;
void *raw_jited_linfo;
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 5f04f56e1eb6..cfeb6a44480b 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -17,6 +17,9 @@
#include "libbpf_internal.h"
#include "hashmap.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
#define BTF_MAX_NR_TYPES 0x7fffffff
#define BTF_MAX_STR_OFFSET 0x7fffffff
diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c
index e95f7710f210..885acebd4396 100644
--- a/tools/lib/bpf/btf_dump.c
+++ b/tools/lib/bpf/btf_dump.c
@@ -18,6 +18,9 @@
#include "libbpf.h"
#include "libbpf_internal.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
static const char PREFIXES[] = "\t\t\t\t\t\t\t\t\t\t\t\t\t";
static const size_t PREFIX_CNT = sizeof(PREFIXES) - 1;
diff --git a/tools/lib/bpf/hashmap.c b/tools/lib/bpf/hashmap.c
index 6122272943e6..54c30c802070 100644
--- a/tools/lib/bpf/hashmap.c
+++ b/tools/lib/bpf/hashmap.c
@@ -12,6 +12,9 @@
#include <linux/err.h>
#include "hashmap.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
/* start with 4 buckets */
#define HASHMAP_MIN_CAP_BITS 2
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 3afd780b0f06..0c229f00a67e 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -55,6 +55,9 @@
#include "libbpf_internal.h"
#include "hashmap.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
#ifndef EM_BPF
#define EM_BPF 247
#endif
@@ -6475,7 +6478,7 @@ static int bpf_object__collect_struct_ops_map_reloc(struct bpf_object *obj,
Elf_Data *symbols;
unsigned int moff;
const char *name;
- u32 member_idx;
+ __u32 member_idx;
GElf_Sym sym;
GElf_Rel rel;
int i, nrels;
diff --git a/tools/lib/bpf/libbpf_errno.c b/tools/lib/bpf/libbpf_errno.c
index 4343e40588c6..0afb51f7a919 100644
--- a/tools/lib/bpf/libbpf_errno.c
+++ b/tools/lib/bpf/libbpf_errno.c
@@ -13,6 +13,9 @@
#include "libbpf.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
#define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START)
#define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c)
#define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START)
diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c
index 320697f8e4c7..8cc992bc532a 100644
--- a/tools/lib/bpf/libbpf_probes.c
+++ b/tools/lib/bpf/libbpf_probes.c
@@ -17,6 +17,9 @@
#include "libbpf.h"
#include "libbpf_internal.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
static bool grep(const char *buffer, const char *pattern)
{
return !!strstr(buffer, pattern);
diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c
index 5065c1aa1061..431bd25c6cdb 100644
--- a/tools/lib/bpf/netlink.c
+++ b/tools/lib/bpf/netlink.c
@@ -15,6 +15,9 @@
#include "libbpf_internal.h"
#include "nlattr.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
#ifndef SOL_NETLINK
#define SOL_NETLINK 270
#endif
diff --git a/tools/lib/bpf/nlattr.c b/tools/lib/bpf/nlattr.c
index 8db44bbfc66d..0ad41dfea8eb 100644
--- a/tools/lib/bpf/nlattr.c
+++ b/tools/lib/bpf/nlattr.c
@@ -13,6 +13,9 @@
#include <string.h>
#include <stdio.h>
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
static uint16_t nla_attr_minlen[LIBBPF_NLA_TYPE_MAX+1] = {
[LIBBPF_NLA_U8] = sizeof(uint8_t),
[LIBBPF_NLA_U16] = sizeof(uint16_t),
diff --git a/tools/lib/bpf/str_error.c b/tools/lib/bpf/str_error.c
index b8064eedc177..146da01979c7 100644
--- a/tools/lib/bpf/str_error.c
+++ b/tools/lib/bpf/str_error.c
@@ -4,6 +4,9 @@
#include <stdio.h>
#include "str_error.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
/*
* Wrapper to allow for building in non-GNU systems such as Alpine Linux's musl
* libc, while checking strerror_r() return to avoid having to check this in
diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c
index 8e0ffa800a71..9807903f121e 100644
--- a/tools/lib/bpf/xsk.c
+++ b/tools/lib/bpf/xsk.c
@@ -32,6 +32,9 @@
#include "libbpf_internal.h"
#include "xsk.h"
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
#ifndef SOL_XDP
#define SOL_XDP 283
#endif
--
2.17.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [Potential Spoof] [PATCH bpf-next] libbpf: poison kernel-only integer types
2020-01-10 18:19 [PATCH bpf-next] libbpf: poison kernel-only integer types Andrii Nakryiko
@ 2020-01-10 18:29 ` Martin Lau
2020-01-10 18:39 ` Alexei Starovoitov
1 sibling, 0 replies; 3+ messages in thread
From: Martin Lau @ 2020-01-10 18:29 UTC (permalink / raw)
To: Andrii Nakryiko
Cc: bpf, netdev, Alexei Starovoitov, daniel, andrii.nakryiko, Kernel Team
On Fri, Jan 10, 2020 at 10:19:16AM -0800, Andrii Nakryiko wrote:
> It's been a recurring issue with types like u32 slipping into libbpf source
> code accidentally. This is not detected during builds inside kernel source
> tree, but becomes a compilation error in libbpf's Github repo. Libbpf is
> supposed to use only __{s,u}{8,16,32,64} typedefs, so poison {s,u}{8,16,32,64}
> explicitly in every .c file. Doing that in a bit more centralized way, e.g.,
> inside libbpf_internal.h breaks selftests, which are both using kernel u32 and
> libbpf_internal.h.
>
> This patch also fixes a new u32 occurence in libbpf.c, added recently.
>
> Fixes: 590a00888250 ("bpf: libbpf: Add STRUCT_OPS support")
> Signed-off-by: Andrii Nakryiko <andriin@fb.com>
> ---
> tools/lib/bpf/bpf.c | 3 +++
> tools/lib/bpf/bpf_prog_linfo.c | 3 +++
> tools/lib/bpf/btf.c | 3 +++
> tools/lib/bpf/btf_dump.c | 3 +++
> tools/lib/bpf/hashmap.c | 3 +++
> tools/lib/bpf/libbpf.c | 5 ++++-
> tools/lib/bpf/libbpf_errno.c | 3 +++
> tools/lib/bpf/libbpf_probes.c | 3 +++
> tools/lib/bpf/netlink.c | 3 +++
> tools/lib/bpf/nlattr.c | 3 +++
> tools/lib/bpf/str_error.c | 3 +++
> tools/lib/bpf/xsk.c | 3 +++
> 12 files changed, 37 insertions(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
> index b0ecbe9ef2d4..500afe478e94 100644
> --- a/tools/lib/bpf/bpf.c
> +++ b/tools/lib/bpf/bpf.c
> @@ -32,6 +32,9 @@
> #include "libbpf.h"
> #include "libbpf_internal.h"
>
> +/* make sure libbpf doesn't use kernel-only integer typedefs */
> +#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
> +
> /*
> * When building perf, unistd.h is overridden. __NR_bpf is
> * required to be defined explicitly.
> diff --git a/tools/lib/bpf/bpf_prog_linfo.c b/tools/lib/bpf/bpf_prog_linfo.c
> index 3ed1a27b5f7c..bafca49cb1e6 100644
> --- a/tools/lib/bpf/bpf_prog_linfo.c
> +++ b/tools/lib/bpf/bpf_prog_linfo.c
> @@ -8,6 +8,9 @@
> #include "libbpf.h"
> #include "libbpf_internal.h"
>
> +/* make sure libbpf doesn't use kernel-only integer typedefs */
> +#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
> +
> struct bpf_prog_linfo {
> void *raw_linfo;
> void *raw_jited_linfo;
> diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
> index 5f04f56e1eb6..cfeb6a44480b 100644
> --- a/tools/lib/bpf/btf.c
> +++ b/tools/lib/bpf/btf.c
> @@ -17,6 +17,9 @@
> #include "libbpf_internal.h"
> #include "hashmap.h"
>
> +/* make sure libbpf doesn't use kernel-only integer typedefs */
> +#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
> +
> #define BTF_MAX_NR_TYPES 0x7fffffff
> #define BTF_MAX_STR_OFFSET 0x7fffffff
>
> diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c
> index e95f7710f210..885acebd4396 100644
> --- a/tools/lib/bpf/btf_dump.c
> +++ b/tools/lib/bpf/btf_dump.c
> @@ -18,6 +18,9 @@
> #include "libbpf.h"
> #include "libbpf_internal.h"
>
> +/* make sure libbpf doesn't use kernel-only integer typedefs */
> +#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
> +
> static const char PREFIXES[] = "\t\t\t\t\t\t\t\t\t\t\t\t\t";
> static const size_t PREFIX_CNT = sizeof(PREFIXES) - 1;
>
> diff --git a/tools/lib/bpf/hashmap.c b/tools/lib/bpf/hashmap.c
> index 6122272943e6..54c30c802070 100644
> --- a/tools/lib/bpf/hashmap.c
> +++ b/tools/lib/bpf/hashmap.c
> @@ -12,6 +12,9 @@
> #include <linux/err.h>
> #include "hashmap.h"
>
> +/* make sure libbpf doesn't use kernel-only integer typedefs */
> +#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
> +
> /* start with 4 buckets */
> #define HASHMAP_MIN_CAP_BITS 2
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 3afd780b0f06..0c229f00a67e 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -55,6 +55,9 @@
> #include "libbpf_internal.h"
> #include "hashmap.h"
>
> +/* make sure libbpf doesn't use kernel-only integer typedefs */
> +#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
> +
> #ifndef EM_BPF
> #define EM_BPF 247
> #endif
> @@ -6475,7 +6478,7 @@ static int bpf_object__collect_struct_ops_map_reloc(struct bpf_object *obj,
> Elf_Data *symbols;
> unsigned int moff;
> const char *name;
> - u32 member_idx;
> + __u32 member_idx;
Acked-by: Martin KaFai Lau <kafai@fb.com>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH bpf-next] libbpf: poison kernel-only integer types
2020-01-10 18:19 [PATCH bpf-next] libbpf: poison kernel-only integer types Andrii Nakryiko
2020-01-10 18:29 ` [Potential Spoof] " Martin Lau
@ 2020-01-10 18:39 ` Alexei Starovoitov
1 sibling, 0 replies; 3+ messages in thread
From: Alexei Starovoitov @ 2020-01-10 18:39 UTC (permalink / raw)
To: Andrii Nakryiko
Cc: bpf, Network Development, Alexei Starovoitov, Daniel Borkmann,
Martin KaFai Lau, Andrii Nakryiko, Kernel Team
On Fri, Jan 10, 2020 at 10:19 AM Andrii Nakryiko <andriin@fb.com> wrote:
>
> It's been a recurring issue with types like u32 slipping into libbpf source
> code accidentally. This is not detected during builds inside kernel source
> tree, but becomes a compilation error in libbpf's Github repo. Libbpf is
> supposed to use only __{s,u}{8,16,32,64} typedefs, so poison {s,u}{8,16,32,64}
> explicitly in every .c file. Doing that in a bit more centralized way, e.g.,
> inside libbpf_internal.h breaks selftests, which are both using kernel u32 and
> libbpf_internal.h.
>
> This patch also fixes a new u32 occurence in libbpf.c, added recently.
>
> Fixes: 590a00888250 ("bpf: libbpf: Add STRUCT_OPS support")
> Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Applied. Thanks
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2020-01-10 18:39 UTC | newest]
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2020-01-10 18:19 [PATCH bpf-next] libbpf: poison kernel-only integer types Andrii Nakryiko
2020-01-10 18:29 ` [Potential Spoof] " Martin Lau
2020-01-10 18:39 ` Alexei Starovoitov
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