From: Kees Cook <keescook@chromium.org>
To: Bernd Edlinger <bernd.edlinger@hotmail.de>
Cc: Oleg Nesterov <oleg@redhat.com>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Alexey Dobriyan <adobriyan@gmail.com>,
Andy Lutomirski <luto@amacapital.net>,
Will Drewry <wad@chromium.org>,
Christian Brauner <brauner@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Michal Hocko <mhocko@suse.com>, Serge Hallyn <serge@hallyn.com>,
James Morris <jamorris@linux.microsoft.com>,
Randy Dunlap <rdunlap@infradead.org>,
Suren Baghdasaryan <surenb@google.com>,
Yafang Shao <laoar.shao@gmail.com>, Helge Deller <deller@gmx.de>,
"Eric W. Biederman" <ebiederm@xmission.com>,
Adrian Reber <areber@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>,
Jens Axboe <axboe@kernel.dk>, Alexei Starovoitov <ast@kernel.org>,
"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
linux-kselftest@vger.kernel.org, linux-mm@kvack.org,
tiozhang <tiozhang@didiglobal.com>,
Luis Chamberlain <mcgrof@kernel.org>,
"Paulo Alcantara (SUSE)" <pc@manguebit.com>,
Sergey Senozhatsky <senozhatsky@chromium.org>,
Frederic Weisbecker <frederic@kernel.org>,
YueHaibing <yuehaibing@huawei.com>,
Paul Moore <paul@paul-moore.com>,
Aleksa Sarai <cyphar@cyphar.com>,
Stefan Roesch <shr@devkernel.io>, Chao Yu <chao@kernel.org>,
xu xin <xu.xin16@zte.com.cn>, Jeff Layton <jlayton@kernel.org>,
Jan Kara <jack@suse.cz>, David Hildenbrand <david@redhat.com>,
Dave Chinner <dchinner@redhat.com>, Shuah Khan <shuah@kernel.org>,
Zheng Yejian <zhengyejian1@huawei.com>,
Elena Reshetova <elena.reshetova@intel.com>,
David Windsor <dwindsor@gmail.com>,
Mateusz Guzik <mjguzik@gmail.com>,
Ard Biesheuvel <ardb@kernel.org>,
"Joel Fernandes (Google)" <joel@joelfernandes.org>,
"Matthew Wilcox (Oracle)" <willy@infradead.org>,
Hans Liljestrand <ishkamiel@gmail.com>
Subject: Re: [PATCH v14] exec: Fix dead-lock in de_thread with ptrace_attach
Date: Tue, 23 Jan 2024 16:09:12 -0800 [thread overview]
Message-ID: <202401231555.59B7EDBB2@keescook> (raw)
In-Reply-To: <AS8P193MB1285110CC784C4BB30DAC0CAE4742@AS8P193MB1285.EURP193.PROD.OUTLOOK.COM>
On Tue, Jan 23, 2024 at 07:30:52PM +0100, Bernd Edlinger wrote:
> - Currently a non-privileged program can potentially send such a privileged
> tracer into a deadlock.
> - With the alternative patch below that non-privileged can no longer send the
> tracer into a deadlock, but it can still quickly escape out of the tracer's
> control.
> - But with my latest patch a sufficiently privileged tracer can neither be
> sent into a deadlock nor can the attached process escape. Mission completed.
Thanks for the details. And it would be pretty unfriendly to fail the execve()
too (or, rather, it makes the execve failure unpredictable). I'll keep
reading your patch...
--
Kees Cook
next prev parent reply other threads:[~2024-01-24 0:09 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-17 12:23 [PATCH v10] exec: Fix dead-lock in de_thread with ptrace_attach Bernd Edlinger
2021-07-11 17:43 ` [PATCH v11] " Bernd Edlinger
2023-10-30 5:20 ` [PATCH v12] " Bernd Edlinger
2023-10-30 9:00 ` kernel test robot
2023-11-06 6:41 ` [PATCH v13] " Bernd Edlinger
2024-01-15 19:22 ` [PATCH v14] " Bernd Edlinger
2024-01-15 19:37 ` Matthew Wilcox
2024-01-17 9:51 ` Bernd Edlinger
2024-01-16 15:22 ` Oleg Nesterov
2024-01-17 15:07 ` Bernd Edlinger
2024-01-17 16:38 ` Oleg Nesterov
2024-01-22 13:24 ` Bernd Edlinger
2024-01-22 13:44 ` Oleg Nesterov
2024-01-22 21:30 ` Kees Cook
2024-01-23 18:30 ` Bernd Edlinger
2024-01-24 0:09 ` Kees Cook [this message]
2024-01-22 18:31 ` [PATCH v15] " Bernd Edlinger
2025-08-18 6:04 ` Jain, Ayush
2025-08-18 20:53 ` [PATCH v16] " Bernd Edlinger
2025-08-19 4:36 ` Kees Cook
2025-08-19 18:53 ` Bernd Edlinger
2025-08-21 17:34 ` [PATCH v17] " Bernd Edlinger
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