linux-kernel - Re: [PATCH] mremap.2: Add note about mremap with locked areas

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 31 Aug 2015 11:14:03 +0200
From:	Michal Hocko <mhocko@...nel.org>
To:	Eric B Munson <emunson@...mai.com>
Cc:	mtk.manpages@...il.com, David Rientjes <rientjes@...gle.com>,
	linux-man@...r.kernel.org, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] mremap.2: Add note about mremap with locked areas

On Fri 28-08-15 14:42:52, Eric B Munson wrote:
> When mremap() is used to move or expand a mapping that is locked with
> mlock() or equivalent it will attempt to populate the new area.
> However, like mmap(MAP_LOCKED), mremap() will not fail if the area
> cannot be populated.  Also like mmap(MAP_LOCKED) this might come as a
> surprise to users and should be noted.
> 
> Signed-off-by: Eric B Munson <emunson@...mai.com>
> Cc: Michal Hocko <mhocko@...e.cz>

Acked-by: Michal Hocko <mhocko@...e.com>

Thank you for following on this.

> Cc: David Rientjes <rientjes@...gle.com>
> Cc: linux-man@...r.kernel.org
> Cc: linux-mm@...ck.org
> Cc: linux-kernel@...r.kernel.org
> ---
>  man2/mremap.2 | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/man2/mremap.2 b/man2/mremap.2
> index 071adb5..cf884e6 100644
> --- a/man2/mremap.2
> +++ b/man2/mremap.2
> @@ -196,6 +196,17 @@ and the prototype for
>  did not allow for the
>  .I new_address
>  argument.
> +
> +If
> +.BR mremap ()
> +is used to move or expand an area locked with
> +.BR mlock (2)
> +or equivalent, the
> +.BR mremap ()
> +call will make a best effort to populate the new area but will not fail
> +with
> +.B ENOMEM
> +if the area cannot be populated.
>  .SH SEE ALSO
>  .BR brk (2),
>  .BR getpagesize (2),
> -- 
> 1.9.1

-- 
Michal Hocko
SUSE Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/