Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct bpf_stack_map.
Cc: Song Liu <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: Martin KaFai Lau <[email protected]>
Cc: Yonghong Song <[email protected]>
Cc: John Fastabend <[email protected]>
Cc: KP Singh <[email protected]>
Cc: Stanislav Fomichev <[email protected]>
Cc: Hao Luo <[email protected]>
Cc: "Gustavo A. R. Silva" <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook <[email protected]>
---
kernel/bpf/stackmap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 458bb80b14d5..d6b277482085 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -28,7 +28,7 @@ struct bpf_stack_map {
void *elems;
struct pcpu_freelist freelist;
u32 n_buckets;
- struct stack_map_bucket *buckets[];
+ struct stack_map_bucket *buckets[] __counted_by(n_buckets);
};
static inline bool stack_map_use_build_id(struct bpf_map *map)
--
2.34.1
On 10/06, Kees Cook wrote:
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
> array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
>
> As found with Coccinelle[1], add __counted_by for struct bpf_stack_map.
>
> Cc: Song Liu <[email protected]>
> Cc: Jiri Olsa <[email protected]>
> Cc: Alexei Starovoitov <[email protected]>
> Cc: Daniel Borkmann <[email protected]>
> Cc: Andrii Nakryiko <[email protected]>
> Cc: Martin KaFai Lau <[email protected]>
> Cc: Yonghong Song <[email protected]>
> Cc: John Fastabend <[email protected]>
> Cc: KP Singh <[email protected]>
> Cc: Stanislav Fomichev <[email protected]>
> Cc: Hao Luo <[email protected]>
> Cc: "Gustavo A. R. Silva" <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <[email protected]>
TIL about __counted_by :-)
Acked-by: Stanislav Fomichev <[email protected]>
> ---
> kernel/bpf/stackmap.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
> index 458bb80b14d5..d6b277482085 100644
> --- a/kernel/bpf/stackmap.c
> +++ b/kernel/bpf/stackmap.c
> @@ -28,7 +28,7 @@ struct bpf_stack_map {
> void *elems;
> struct pcpu_freelist freelist;
> u32 n_buckets;
> - struct stack_map_bucket *buckets[];
> + struct stack_map_bucket *buckets[] __counted_by(n_buckets);
> };
>
> static inline bool stack_map_use_build_id(struct bpf_map *map)
> --
> 2.34.1
>
Hello:
This patch was applied to bpf/bpf-next.git (master)
by Daniel Borkmann <[email protected]>:
On Fri, 6 Oct 2023 13:17:00 -0700 you wrote:
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
> array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
>
> As found with Coccinelle[1], add __counted_by for struct bpf_stack_map.
>
> [...]
Here is the summary with links:
- bpf: Annotate struct bpf_stack_map with __counted_by
https://git.kernel.org/bpf/bpf-next/c/84cb9cbd911a
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
On 10/6/23 22:17, Kees Cook wrote:
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
> array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
>
> As found with Coccinelle[1], add __counted_by for struct bpf_stack_map.
>
> Cc: Song Liu <[email protected]>
> Cc: Jiri Olsa <[email protected]>
> Cc: Alexei Starovoitov <[email protected]>
> Cc: Daniel Borkmann <[email protected]>
> Cc: Andrii Nakryiko <[email protected]>
> Cc: Martin KaFai Lau <[email protected]>
> Cc: Yonghong Song <[email protected]>
> Cc: John Fastabend <[email protected]>
> Cc: KP Singh <[email protected]>
> Cc: Stanislav Fomichev <[email protected]>
> Cc: Hao Luo <[email protected]>
> Cc: "Gustavo A. R. Silva" <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Gustavo A. R. Silva <[email protected]>
Thanks!
--
Gustavo
> ---
> kernel/bpf/stackmap.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
> index 458bb80b14d5..d6b277482085 100644
> --- a/kernel/bpf/stackmap.c
> +++ b/kernel/bpf/stackmap.c
> @@ -28,7 +28,7 @@ struct bpf_stack_map {
> void *elems;
> struct pcpu_freelist freelist;
> u32 n_buckets;
> - struct stack_map_bucket *buckets[];
> + struct stack_map_bucket *buckets[] __counted_by(n_buckets);
> };
>
> static inline bool stack_map_use_build_id(struct bpf_map *map)