linux-kernel - Re: [PATCH] uprobes: use vm_special

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: <yt9d7cbso7p8.fsf@linux.ibm.com>
Date: Tue, 03 Sep 2024 21:31:15 +0200
From: Sven Schnelle <svens@...ux.ibm.com>
To: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Oleg Nesterov <oleg@...hat.com>, Michael Ellerman <mpe@...erman.id.au>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Peter Zijlstra
 <peterz@...radead.org>, Ingo Molnar <mingo@...hat.com>,
        Arnaldo Carvalho
 de Melo <acme@...nel.org>,
        Namhyung Kim <namhyung@...nel.org>,
        Mark
 Rutland <mark.rutland@....com>,
        Alexander Shishkin
 <alexander.shishkin@...ux.intel.com>,
        Jiri Olsa <jolsa@...nel.org>, Ian
 Rogers <irogers@...gle.com>,
        Adrian Hunter <adrian.hunter@...el.com>,
        "Liang, Kan" <kan.liang@...ux.intel.com>, linux-kernel@...r.kernel.org,
        linux-trace-kernel@...r.kernel.org, linux-perf-users@...r.kernel.org
Subject: Re: [PATCH] uprobes: use vm_special_mapping close() functionality

Hi Linus,

Linus Torvalds <torvalds@...ux-foundation.org> writes:

> On Tue, 3 Sept 2024 at 02:09, Oleg Nesterov <oleg@...hat.com> wrote:
>>
>> but with or without this fix __create_xol_area() also needs
>>
>>         area->xol_mapping.mremap = NULL;
>
> I think the whole thing needs to be zeroed out.
>
> It was always horribly buggy. The close thing just made it more
> *obviously* buggy, because closing a vma is a lot more common than
> mremap'ing it.
>
> Either use kzalloc(), or do a proper initializer something like this:

I sent a patch which does this today:

https://lore.kernel.org/all/20240903102313.3402529-1-svens@linux.ibm.com/