From: Christian Brauner <brauner@kernel.org>
To: John Ericson <John.Ericson@Obsidian.Systems>
Cc: Andy Lutomirski <luto@kernel.org>,
Al Viro <viro@zeniv.linux.org.uk>,
Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
David Howells <dhowells@redhat.com>,
Chuck Lever <cel@kernel.org>, Jeff Layton <jlayton@kernel.org>,
Shuah Khan <skhan@linuxfoundation.org>,
David Laight <david.laight.linux@gmail.com>,
"H. Peter Anvin" <hpa@zytor.com>, Li Chen <me@linux.beauty>,
Cong Wang <cwang@multikernel.io>, Arnd Bergmann <arnd@arndb.de>,
Thomas Gleixner <tglx@kernel.org>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
Jonathan Corbet <corbet@lwn.net>, Kees Cook <kees@kernel.org>,
Sergei Zimmerman <sergei@zimmerman.foo>,
Farid Zakaria <farid.m.zakaria@gmail.com>,
linux-arch <linux-arch@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-api <linux-api@vger.kernel.org>,
netfs <netfs@lists.linux.dev>,
linux-nfs <linux-nfs@vger.kernel.org>,
John Ericson <mail@JohnEricson.me>
Subject: Re: [RFC PATCH 2/3] fs: support tasks with a null root or cwd
Date: Mon, 29 Jun 2026 11:19:15 +0200 [thread overview]
Message-ID: <20260629-defizit-typisch-maulkorb-53953a5a8510@brauner> (raw)
In-Reply-To: <20260629065934.1425479-3-John.Ericson@Obsidian.Systems>
> A task's root directory (`fs->root`) and current working directory
> (`fs->pwd`) are normally established by `chroot(2)`/`pivot_root(2)` and
> `chdir(2)`/`fchdir(2)` (or inherited across `fork(2)`). Allow either to
> instead be the null path, as documented in `struct fs_struct`. The two
> are independent: a task may opt out of one, the other, or both.
No, absolutely we're not going to have tasks with struct path's in their
struct fs_struct that have NULL members in them. struct path is used
insanely widely in the kernel this is just an an open invitation for a
slew of security bugs. Not going to happen.
--
Christian Brauner <brauner@kernel.org>
next prev parent reply other threads:[~2026-06-29 9:19 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-06-29 6:58 [RFC PATCH 0/3] fs: support tasks with a null root or cwd John Ericson
2026-06-29 6:58 ` [RFC PATCH 1/3] fs: Add documentation to some `struct fs_struct` fields John Ericson
2026-06-29 6:58 ` [RFC PATCH 2/3] fs: support tasks with a null root or cwd John Ericson
2026-06-29 9:19 ` Christian Brauner [this message]
2026-06-29 6:58 ` [RFC PATCH 3/3] fs: add KUnit tests for " John Ericson
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