From: Steven Rostedt <rostedt@goodmis.org>
To: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org
Subject: Re: [PATCH v8 3/6] tracefs: Check file permission even if user has CAP_DAC_OVERRIDE
Date: Wed, 11 Feb 2026 10:46:23 -0500 [thread overview]
Message-ID: <20260211104623.73fd4fc3@fedora> (raw)
In-Reply-To: <177071303130.2293046.2400906233143699263.stgit@mhiramat.tok.corp.google.com>
On Tue, 10 Feb 2026 17:43:51 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:
> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
>
> Strictly checking the file read/write permission even if the owner has
> CAP_DAC_OVERRIDE on tracefs as same as sysfs.
> Tracefs is a pseudo filesystem, just like sysfs, so any file that the
> system defines as unwritable should actually be unwritable by anyone.
This is getting too complex and still doesn't work. As I said in my
other email, simply check for the trace_array being readonly on opens()
and return -EACCES if it is and was opened for write or read-write.
With this still not working this late in the game, it will need to wait
until the next merge window. I'll take the first two patches of this
series now though.
-- Steve
next prev parent reply other threads:[~2026-02-11 15:46 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-10 8:43 [PATCH v8 0/6] tracing: Remove backup instance after read all Masami Hiramatsu (Google)
2026-02-10 8:43 ` [PATCH v8 1/6] tracing: Fix to set write permission to per-cpu buffer_size_kb Masami Hiramatsu (Google)
2026-02-10 8:43 ` [PATCH v8 2/6] tracing: Reset last_boot_info if ring buffer is reset Masami Hiramatsu (Google)
2026-02-10 8:43 ` [PATCH v8 3/6] tracefs: Check file permission even if user has CAP_DAC_OVERRIDE Masami Hiramatsu (Google)
2026-02-11 15:46 ` Steven Rostedt [this message]
2026-02-12 6:15 ` Masami Hiramatsu
2026-03-05 17:33 ` Steven Rostedt
2026-03-24 16:43 ` Steven Rostedt
2026-02-10 8:43 ` [PATCH v8 4/6] tracing: Make the backup instance non-reusable Masami Hiramatsu (Google)
2026-02-10 8:44 ` [PATCH v8 5/6] tracing: Remove the backup instance automatically after read Masami Hiramatsu (Google)
2026-02-10 8:44 ` [PATCH v8 6/6] tracing/Documentation: Add a section about backup instance Masami Hiramatsu (Google)
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