linux-kernel - Re: [PATCH perf/core 09/22] uprobes/x86: Add uprobe syscall to speed up uprobe

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: <20250427155059.GD9350@redhat.com>
Date: Sun, 27 Apr 2025 17:51:00 +0200
From: Oleg Nesterov <oleg@...hat.com>
To: Jiri Olsa <jolsa@...nel.org>
Cc: Peter Zijlstra <peterz@...radead.org>,
	Andrii Nakryiko <andrii@...nel.org>, bpf@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-trace-kernel@...r.kernel.org,
	x86@...nel.org, Song Liu <songliubraving@...com>,
	Yonghong Song <yhs@...com>,
	John Fastabend <john.fastabend@...il.com>,
	Hao Luo <haoluo@...gle.com>, Steven Rostedt <rostedt@...dmis.org>,
	Masami Hiramatsu <mhiramat@...nel.org>,
	Alan Maguire <alan.maguire@...cle.com>,
	David Laight <David.Laight@...LAB.COM>,
	Thomas Weißschuh <thomas@...ch.de>,
	Ingo Molnar <mingo@...nel.org>
Subject: Re: [PATCH perf/core 09/22] uprobes/x86: Add uprobe syscall to speed
 up uprobe

On 04/21, Jiri Olsa wrote:
>
> We do not allow to execute uprobe syscall if the caller is not
> from uprobe trampoline mapping.

...

> +SYSCALL_DEFINE0(uprobe)
> +{
> +	struct pt_regs *regs = task_pt_regs(current);
> +	unsigned long ip, sp, ax_r11_cx_ip[4];
> +	int err;
> +
> +	/* Allow execution only from uprobe trampolines. */
> +	if (!in_uprobe_trampoline(regs->ip))
> +		goto sigill;

I honestly don't understand why do we need this check. Same for the similar
trampoline_check_ip() check in sys_uretprobe(). Nevermind, I won't argue.

Oleg.