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From: adobriyan@gmail.com (Alexey Dobriyan)
To: linux-security-module@vger.kernel.org
Subject: [PATCH] proc: prevent a task from writing on its own /proc/*/mem
Date: Sat, 26 May 2018 18:48:19 +0300	[thread overview]
Message-ID: <20180526154819.GA14016@avx2> (raw)
In-Reply-To: <1527346246-1334-1-git-send-email-s.mesoraca16@gmail.com>

On Sat, May 26, 2018 at 04:50:46PM +0200, Salvatore Mesoraca wrote:
> Prevent a task from opening, in "write" mode, any /proc/*/mem
> file that operates on the task's mm.
> /proc/*/mem is mainly a debugging means and, as such, it shouldn't
> be used by the inspected process itself.
> Current implementation always allow a task to access its own
> /proc/*/mem file.
> A process can use it to overwrite read-only memory, making
> pointless the use of security_file_mprotect() or other ways to
> enforce RO memory.

You can do it in security_ptrace_access_check() or security_file_open()
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  reply	other threads:[~2018-05-26 15:48 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-26 14:50 [PATCH] proc: prevent a task from writing on its own /proc/*/mem Salvatore Mesoraca
2018-05-26 15:48 ` Alexey Dobriyan [this message]
2018-05-26 17:30   ` Salvatore Mesoraca
2018-05-26 17:53     ` Casey Schaufler
2018-05-26 17:58     ` Alexey Dobriyan
2018-05-27  0:31 ` Kees Cook
2018-05-27  1:33   ` Linus Torvalds
2018-05-27 14:41     ` Kees Cook
2018-05-28  9:32     ` Salvatore Mesoraca
2018-06-04 16:57       ` Steve Kemp
2018-06-04 18:03         ` Casey Schaufler
2018-06-10  7:40         ` Salvatore Mesoraca
2018-05-28  9:06 ` Jann Horn
2018-05-28  9:33   ` Salvatore Mesoraca

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