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Date:   Fri, 1 May 2020 14:02:16 +1000 (AEST)
From:   James Morris <jmorris@namei.org>
To:     =?ISO-8859-15?Q?Micka=EBl_Sala=FCn?= <mic@digikod.net>
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Subject: Re: [PATCH v3 2/5] fs: Add a MAY_EXECMOUNT flag to infer the noexec
 mount property
In-Reply-To: <20200428175129.634352-3-mic@digikod.net>
Message-ID: <alpine.LRH.2.21.2005011357290.29679@namei.org>
References: <20200428175129.634352-1-mic@digikod.net> <20200428175129.634352-3-mic@digikod.net>
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On Tue, 28 Apr 2020, Micka?l Sala?n wrote:

> An LSM doesn't get path information related to an access request to open
> an inode.  This new (internal) MAY_EXECMOUNT flag enables an LSM to
> check if the underlying mount point of an inode is marked as executable.
> This is useful to implement a security policy taking advantage of the
> noexec mount option.
> 
> This flag is set according to path_noexec(), which checks if a mount
> point is mounted with MNT_NOEXEC or if the underlying superblock is
> SB_I_NOEXEC.
> 
> Signed-off-by: Micka?l Sala?n <mic@digikod.net>
> Reviewed-by: Philippe Tr?buchet <philippe.trebuchet@ssi.gouv.fr>
> Reviewed-by: Thibaut Sautereau <thibaut.sautereau@ssi.gouv.fr>
> Cc: Aleksa Sarai <cyphar@cyphar.com>
> Cc: Al Viro <viro@zeniv.linux.org.uk>
> Cc: Kees Cook <keescook@chromium.org>

Are there any existing LSMs which plan to use this aspect?

-- 
James Morris
<jmorris@namei.org>
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