From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH] fs: fix integer overflow in MS_NOUSER definition
Date: Sat, 21 Apr 2012 07:28:38 +0100
Message-ID: <20120421062838.GS6871@ZenIV.linux.org.uk>
References: <20120421054949.32549.2823.stgit@zurg>
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Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
To: Konstantin Khlebnikov <khlebnikov@openvz.org>
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On Sat, Apr 21, 2012 at 09:49:49AM +0400, Konstantin Khlebnikov wrote:
> MS_NOUSER defined as signed int (1<<31), sb->s_flags declared as unsigned long.
> So (sb->s_flags & MS_NOUSER) works as (sb->s_flags & 0xffffffff80000000).

... and it's not a problem since we can't use bits 32 and above anyway -
unsigned long is 32bit on a lot of platforms.  I have no objections to
making that 1U<<31, but it's not a bug, let alone an integer overflow.