netdev - Re: [PATCH bpf-next 0/7] Introduce bpf_line

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:   Sun, 9 Dec 2018 14:08:23 -0800
From:   Alexei Starovoitov <alexei.starovoitov@...il.com>
To:     Martin KaFai Lau <kafai@...com>
Cc:     netdev@...r.kernel.org, Alexei Starovoitov <ast@...com>,
        Daniel Borkmann <daniel@...earbox.net>, kernel-team@...com
Subject: Re: [PATCH bpf-next 0/7] Introduce bpf_line_info

On Fri, Dec 07, 2018 at 04:42:24PM -0800, Martin KaFai Lau wrote:
> This patch series introduces the bpf_line_info.  Please see individual patch
> for details.
> 
> It will be useful for introspection purpose, like:
> 
> [root@...h-fb-vm1 bpf]# ~/devshare/fb-kernel/linux/tools/bpf/bpftool/bpftool prog dump jited pinned /sys/fs/bpf/test_btf_haskv
> [...]
> int test_long_fname_2(struct dummy_tracepoint_args * arg):
> bpf_prog_44a040bf25481309_test_long_fname_2:
> ; static int test_long_fname_2(struct dummy_tracepoint_args *arg)
>    0:   push   %rbp
>    1:   mov    %rsp,%rbp
>    4:   sub    $0x30,%rsp
>    b:   sub    $0x28,%rbp
>    f:   mov    %rbx,0x0(%rbp)
>   13:   mov    %r13,0x8(%rbp)
>   17:   mov    %r14,0x10(%rbp)
>   1b:   mov    %r15,0x18(%rbp)
>   1f:   xor    %eax,%eax
>   21:   mov    %rax,0x20(%rbp)
>   25:   xor    %esi,%esi
> ; int key = 0;
>   27:   mov    %esi,-0x4(%rbp)
> ; if (!arg->sock)
>   2a:   mov    0x8(%rdi),%rdi
> ; if (!arg->sock)
>   2e:   cmp    $0x0,%rdi
>   32:   je     0x0000000000000070
>   34:   mov    %rbp,%rsi
> ; counts = bpf_map_lookup_elem(&btf_map, &key);
>   37:   add    $0xfffffffffffffffc,%rsi
>   3b:   movabs $0xffff8881139d7480,%rdi
>   45:   add    $0x110,%rdi
>   4c:   mov    0x0(%rsi),%eax
>   4f:   cmp    $0x4,%rax
>   53:   jae    0x000000000000005e
>   55:   shl    $0x3,%rax
>   59:   add    %rdi,%rax
>   5c:   jmp    0x0000000000000060
>   5e:   xor    %eax,%eax
> ; if (!counts)
>   60:   cmp    $0x0,%rax
>   64:   je     0x0000000000000070
> ; counts->v6++;
>   66:   mov    0x4(%rax),%edi
>   69:   add    $0x1,%rdi
>   6d:   mov    %edi,0x4(%rax)
>   70:   mov    0x0(%rbp),%rbx
>   74:   mov    0x8(%rbp),%r13
>   78:   mov    0x10(%rbp),%r14
>   7c:   mov    0x18(%rbp),%r15
>   80:   add    $0x28,%rbp
>   84:   leaveq
>   85:   retq
> [...]

Looks great! Applied to bpf-next.
Please follow up with a patch to make use of it in the verifier too.