netdev - Re: [PATCH bpf-next v4 01/11] bpf: Save PTR_TO_BTF_ID register state when spilling to stack

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]

Date:   Wed, 08 Jan 2020 22:06:44 -0300
From:   Arnaldo Carvalho de Melo <arnaldo.melo@...il.com>
To:     Martin KaFai Lau <kafai@...com>, bpf@...r.kernel.org
CC:     Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        David Miller <davem@...emloft.net>, kernel-team@...com,
        netdev@...r.kernel.org
Subject: Re: [PATCH bpf-next v4 01/11] bpf: Save PTR_TO_BTF_ID register state when spilling to stack

On January 8, 2020 9:44:24 PM GMT-03:00, Martin KaFai Lau <kafai@...com> wrote:
>This patch makes the verifier save the PTR_TO_BTF_ID register state
>when
>spilling to the stack.

You say what it does, but not why that is needed :-/

- Arnaldo
>
>Acked-by: Yonghong Song <yhs@...com>
>Signed-off-by: Martin KaFai Lau <kafai@...com>
>---
> kernel/bpf/verifier.c | 1 +
> 1 file changed, 1 insertion(+)
>
>diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
>index 6f63ae7a370c..d433d70022fd 100644
>--- a/kernel/bpf/verifier.c
>+++ b/kernel/bpf/verifier.c
>@@ -1916,6 +1916,7 @@ static bool is_spillable_regtype(enum
>bpf_reg_type type)
> 	case PTR_TO_TCP_SOCK:
> 	case PTR_TO_TCP_SOCK_OR_NULL:
> 	case PTR_TO_XDP_SOCK:
>+	case PTR_TO_BTF_ID:
> 		return true;
> 	default:
> 		return false;