linux-kernel - Re: [PATCH RESEND v3 1/3] ptrace: pass type of a syscall-stop in ptrace

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]

Message-ID: <20181126145643.GD1660@redhat.com>
Date:   Mon, 26 Nov 2018 15:56:43 +0100
From:   Oleg Nesterov <oleg@...hat.com>
To:     Elvira Khabirova <lineprinter@...linux.org>
Cc:     rostedt@...dmis.org, mingo@...hat.com,
        linux-kernel@...r.kernel.org, ldv@...linux.org, esyr@...hat.com,
        luto@...nel.org, strace-devel@...ts.strace.io,
        linux-api@...r.kernel.org
Subject: Re: [PATCH RESEND v3 1/3] ptrace: pass type of a syscall-stop in
 ptrace_message

On 11/25, Elvira Khabirova wrote:
>
> + * These values are stored in task->ptrace_message by tracehook_report_syscall_*
> + * to describe current syscall-stop.
> + *
> + * Values for these constants are chosen so that they do not appear
> + * in task->ptrace_message by other means.
> + */
> +#define PTRACE_EVENTMSG_SYSCALL_ENTRY	0x80000000U
> +#define PTRACE_EVENTMSG_SYSCALL_EXIT	0x90000000U

Stupid question, why not

	#define PTRACE_EVENT_SYSCALL_ENTRY	8
	#define PTRACE_EVENT_SYSCALL_EXIT	9

right after other PTRACE_EVENT_* constants?

The next 3/3 tries to detect PTRACE_EVENT_SECCOMP case anyway, so I am not sure
I understand what "do not appear in task->ptrace_message by other means" actually
means...

Oleg.