Re: [PATCH] ptrace.2: Add details about usage of PTRACE_GET_SYSCALL_INFO

["Dmitry V . Levin" <ldv@strace.io>]

On Sat, Feb 25, 2023 at 04:42:12AM +0200, Fotios Valasiadis wrote:
> Fixed incomplete doc. PTRACE_GET_SYSCALL_INFO wouldn't inform the user that they need to enable PTRACE_O_TRACESYSGOOD to get detailed information from said operation.

I'm not sure about the word "fix" in this context as we are not
correcting some wrong information but simply extending the documentation.

How about the following wording:

Document the role of PTRACE_O_TRACESYSGOOD option in connection with
PTRACE_GET_SYSCALL_INFO.

> Signed-off-by: Fotios Valasiadis <fvalasiad@gmail.com>
> Cowritten-by: Dmitry V. Levin <ldv@strace.io>

Feel free to add
Complements: fc91449cb "ptrace.2: Document PTRACE_GET_SYSCALL_INFO"

> ---
>  man2/ptrace.2 | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/man2/ptrace.2 b/man2/ptrace.2
> index 55d9fd36d..ad0543b0b 100644
> --- a/man2/ptrace.2
> +++ b/man2/ptrace.2
> @@ -1111,6 +1111,15 @@ stop.
>  .B PTRACE_SYSCALL_INFO_NONE
>  No component of the union contains relevant information.
>  .RE
> +.IP
> +Note that in case of
> +syscall entry or exit stops, the data returned by
> +.B PTRACE_GET_SYSCALL_INFO
> +is limited to type
> +.B PTRACE_SYSCALL_INFO_NONE
> +unless
> +.B PTRACE_O_TRACESYSGOOD
> +option is set before the corresponding ptrace stop has occurred.
>  .\"
>  .SS Death under ptrace
>  When a (possibly multithreaded) process receives a killing signal
> -- 
> 2.39.2

-- 
ldv