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Date: Fri, 25 Jun 2004 02:20:57 +0200
From: Wichert Akkerman <wichert@wiggy.net>
To: linux-kernel@vger.kernel.org
Subject: sys_gettimeofday racy or not?
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This just happened to catch my eye and it's probably perfectly
valid, but if so please educate me on why it is. In kernel/time.c
sys_gettimeofday() there is this code:

        if (unlikely(tz != NULL)) {
                if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
                        return -EFAULT;
        }

what prevents sys_tz from being changed while this code runs?

Wichert.

-- 
Wichert Akkerman <wichert@wiggy.net>    It is simple to make things.
http://www.wiggy.net/                   It is hard to make things simple.